U.S. patent application number 13/644982 was filed with the patent office on 2013-07-04 for composite bone graft, method of making and using the same.
This patent application is currently assigned to LifeNet Health. The applicant listed for this patent is LifeNet Health. Invention is credited to Billy G. Anderson, Lloyd Wolfinbarger.
Application Number | 20130173013 13/644982 |
Document ID | / |
Family ID | 26919486 |
Filed Date | 2013-07-04 |
United States Patent
Application |
20130173013 |
Kind Code |
A1 |
Anderson; Billy G. ; et
al. |
July 4, 2013 |
Composite Bone Graft, Method of Making and Using the Same
Abstract
The invention is directed to a composite bone graft for
implantation in a patient, and methods of making and using the
composite bone graft, along with methods for treating patients by
implanting the composite bone graft at a site in a patient.
Inventors: |
Anderson; Billy G.;
(Virginia Beach, VA) ; Wolfinbarger; Lloyd;
(Norfolk, VA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LifeNet Health; |
Virginia Beach |
VA |
US |
|
|
Assignee: |
LifeNet Health
Virginia Beach
VA
|
Family ID: |
26919486 |
Appl. No.: |
13/644982 |
Filed: |
October 4, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13475176 |
May 18, 2012 |
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13644982 |
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10953881 |
Sep 30, 2004 |
8182532 |
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13475176 |
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09698493 |
Oct 27, 2000 |
6902578 |
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10953881 |
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09368263 |
Aug 3, 1999 |
6200347 |
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09698493 |
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09286975 |
Apr 6, 1999 |
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09368263 |
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09225299 |
Jan 5, 1999 |
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09286975 |
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Current U.S.
Class: |
623/23.61 |
Current CPC
Class: |
A61F 2/447 20130101;
A61F 2002/30383 20130101; A61F 2220/0025 20130101; A61F 2230/0082
20130101; A61F 2002/30261 20130101; A61F 2002/30777 20130101; A61F
2230/0006 20130101; A61F 2002/30156 20130101; A61F 2/3094 20130101;
A61F 2002/30904 20130101; A61F 2002/2817 20130101; A61F 2002/30154
20130101; A61F 2002/30785 20130101; A61F 2230/0008 20130101; A61L
27/365 20130101; A61F 2002/30158 20130101; A61F 2/4455 20130101;
A61F 2002/3028 20130101; A61F 2002/30677 20130101; A61L 27/54
20130101; A61F 2002/30387 20130101; A61F 2002/30971 20130101; A61F
2002/30604 20130101; A61F 2002/30153 20130101; A61F 2002/30057
20130101; A61F 2310/00017 20130101; A61F 2002/30492 20130101; A61L
27/40 20130101; A61F 2230/0017 20130101; A61F 2002/30113 20130101;
A61F 2310/00329 20130101; A61F 2230/0023 20130101; A61F 2230/0013
20130101; A61L 27/36 20130101; A61F 2002/2835 20130101; A61F
2240/001 20130101; A61F 2230/0019 20130101; A61L 2430/02 20130101;
A61L 27/14 20130101; A61L 27/54 20130101; A61L 27/36 20130101; A61F
2310/00029 20130101; A61L 27/02 20130101; A61L 27/14 20130101; A61F
2002/30263 20130101; A61F 2002/30599 20130101; A61F 2230/0084
20130101; A61F 2250/0014 20130101; A61F 2002/30004 20130101; A61F
2210/0004 20130101; A61F 2002/30131 20130101; A61L 27/02 20130101;
A61L 27/446 20130101; A61F 2310/00179 20130101; A61F 2002/30125
20130101; A61L 27/48 20130101; A61F 2002/30329 20130101; A61F
2002/2839 20130101; A61F 2/28 20130101; A61F 2002/30224 20130101;
A61F 2002/30494 20130101; A61F 2230/0021 20130101; A61L 27/40
20130101; A61F 2230/0063 20130101; A61F 2002/30062 20130101; A61F
2230/0069 20130101; A61F 2250/0063 20130101; A61L 27/3608 20130101;
A61F 2002/30143 20130101; A61F 2230/0026 20130101; A61F 2/442
20130101; A61L 27/46 20130101; A61F 2310/00023 20130101 |
Class at
Publication: |
623/23.61 |
International
Class: |
A61F 2/28 20060101
A61F002/28 |
Claims
1-109. (canceled)
110. A composite bone graft comprising: a plurality of bone
portions layered to form a graft unit, and one or more non-adhesive
biocompatible mechanical connectors connecting said graft unit,
said mechanical connectors comprising one or more biocompatible
materials selected from the group consisting of cortical bone;
stainless steel; titanium; cobalt-chromium-molybdenum alloy; a
plastic of one or more members selected from the group consisting
of nylon, polycarbonate, polypropylene, polyacetal, polyethylene,
and polysulfone; and one or more bioabsorbable polymers.
111. A composite bone graft comprising: two or more distinct bone
portions, and one or more non-adhesive biocompatible mechanical
connectors, wherein said mechanical connectors connect said two or
more bone portions to form said composite bone graft, said
mechanical connectors comprising one or more biocompatible
materials selected from the group consisting of cortical bone;
stainless steel; titanium; cobalt-chromium-molybdenum alloy; a
plastic of one or more members selected from the group consisting
of nylon, polycarbonate, polypropylene, polyacetal, polyethylene,
and polysulfone; and one or more bioabsorbable polymers.
112. A composite bone graft comprising: one or more cortical bone
portions layered to form a first unit; one or more cortical bone
portions layered to form a second unit; one or more cancellous bone
portions layered to form a third unit; said third unit disposed
between said first unit and said second unit to form a graft unit;
and one or more non-adhesive biocompatible mechanical connectors
connecting said graft unit, said mechanical connectors comprising
one or more biocompatible materials selected from the group
consisting of cortical bone; stainless steel; titanium;
cobalt-chromium-molybdenum alloy; a plastic of one or more members
selected from the group consisting of nylon, polycarbonate,
polypropylene, polyacetal, polyethylene, and polysulfone; and one
or more bioabsorbable polymers.
Description
[0001] This application is a Continuation-in-Part application of
U.S. patent application Ser. No. 09/286,975, filed Apr. 6, 1999,
which is a Continuation-in-Part of U.S. patent application Ser. No.
09/225,299, filed Jan. 5, 1999, now pending.
FIELD OF THE INVENTION
[0002] The invention relates to bone grafts and more particularly,
to bone grafts useful for spinal fusion. The invention provides a
composite bone graft for implantation in a patient, and methods of
making and using the composite bone graft. The composite bone graft
contains two or more distinct bone portions where the bone portions
are connected. The bone portions are preferably self-locking,
interlocking, and/or connected by at least one mechanical
connector, including for example, a bone pin. One or more of the
bone portions may be demineralized, and may also be continuous or
discontinuous. The composite bone graft may include one or more
textured surfaces, preferably including a plurality of closely
spaced protrusions. The composite bone graft is useful for
repairing bone defects caused by congenital anomaly, disease, or
trauma, and is particularly useful for spinal fusions. The
composite bone graft can be appropriately sized for any application
and can be used to replace traditional non-bone prosthetic
implants. The composite bone graft promotes the growth of patient
bone at an implantation site by promoting osteoinductivity and
cellularization, provides added stability and mechanical strength,
and does not shift, extrude or rotate, after implantation.
BACKGROUND OF THE INVENTION
[0003] In the field of prosthetic implants, materials often used
include bone grafts and implants produced from non-bone materials,
including for example stainless steel, titanium and plastics. The
choice of whether to use a bone or a non-bone implant often depends
on the clinical indication, implant site, whether the implant is
load-bearing, and the size of the implant needed.
[0004] Prior to the present invention, the use of bone grafts
versus non-bone prosthetic implants to for example, support and
fuse together adjacent vertebrae, has been limited in part by the
physical size of a cortical bone graft. Interbody bone grafting
involves the problem of strength. Strong cortical bone (the outer
layer) is required as a strut in the interbody position to prevent
collapse of the disc space while healing occurs. For example,
cortical bone obtained from a cadaver source fashioned into struts,
is not wide enough for optimum load bearing. This natural
limitation often excludes the use of a bone graft product.
[0005] The success or failure of a bone graft further depends on
whether the bone graft remains at the implant site, is
cellularized, and whether it can withstand the mechanical load. In
spinal surgery, there are two primary indications for use of
allograft bone: (1) when there is insufficient available autograft
bone, and (2) in spinal fusion procedures when a structural element
in needed. Typically, bone grafts are affixed at an implant site by
fusion. Bone grafts for spinal applications often fail because they
are extruded from the implantation site due to shifting, rotation,
and slippage of the graft, are not cellularized, or fail
mechanically.
[0006] The invention enables the use of bone grafts for
applications normally suited for only non-bone prosthetic implants.
The invention solves the problem of graft failure by providing a
composite bone graft which can be appropriately sized for any
application out of for example, strong cortical bone; promotes the
ingrowth of patient bone at an implantation site by promoting
osteoinductivity and cellularization; provides added stability and
mechanical strength; and does not shift, extrude or rotate; after
implantation.
SUMMARY OF THE INVENTION
[0007] The present invention is directed to a composite bone graft
for repairing bone defects caused by congenital anomaly, disease,
or trauma, including for example, for restoring vertical support of
the posterior and/or anterior column. The present composite bone
grafts can be used as structural grafts placed posteriorly in the
spine as interbody grafts or as strut grafts spanning multiple
segments. Posterior composite bone grafts can be used to supplement
autologous bone for spinal fusions in patients who lack sufficient
host bone and to avoid significant donor site morbidity. The
present composite bone grafts can be used for applications normally
suited for only non-bone prosthetic implants because the composite
bone graft can be appropriately sized for any application and has
adequate mechanical strength.
[0008] The invention provides a composite bone graft including a
plurality of bone portions layered to form a graft unit, and one or
more biocompatible connectors for holding together the graft
unit.
[0009] The invention also provides a composite bone graft including
two or more distinct bone portions, and one or more biocompatible
connectors, where the biocompatible connectors hold together the
two or more bone portions to form the composite bone graft.
[0010] The present invention provides a composite bone graft
including two or more connected, distinct bone portions.
[0011] The present invention provides a composite bone graft
including three or more connected, distinct bone portions.
[0012] The present invention provides a composite bone graft
including three or more connected, distinct cortical bone
portions.
[0013] The present invention provides a composite bone graft
including one or more horizontally disposed channels provided
through the composite bone graft perpendicular to the interfaces of
the bone portions.
[0014] The present invention also provides a composite bone graft
including one or more vertically disposed channels provided through
the composite bone graft parallel to the interfaces of the bone
portions.
[0015] The present invention further provides a composite bone
graft including one or more horizontally disposed channels and
vertically disposed channels where the one or more channels
includes one or more therapeutically beneficial substances.
[0016] The invention further provides a composite bone graft
including two or more connected bone portions, where the bone
portions can include cortical bone and cancellous bone.
[0017] The invention also provides a composite bone graft,
including a first bone portion, a second bone portion, a third bone
portion, the first, second and third bone portions are disposed one
on the other (ie. layered) to form a graft unit; and one or more
biocompatible connectors for holding together the graft unit.
[0018] The invention provides a composite bone graft, including a
first cortical bone portion, a second cortical bone portion, a
cancellous bone portion disposed between the first cortical bone
portion and the second cortical bone portion to form a graft unit,
and one or more biocompatible connectors for holding together the
graft unit.
[0019] The invention further provides a composite bone graft,
including a first cortical bone portion, a second cortical bone
portion provided on the first cortical bone portion to form a graft
unit; and one or more biocompatible connectors for holding together
the graft unit.
[0020] The invention provides a composite bone graft, including a
plurality of layered cortical bone portions forming a graft unit,
and one or more biocompatible connectors for holding together the
graft unit.
[0021] The invention provides a composite bone graft, including a
plurality of layered bone portions forming a graft unit, and one or
more biocompatible connectors for holding together the graft
unit.
[0022] The invention also provides a composite bone graft,
including a first bone portion, a second bone portion provided on
the first bone portion to form a graft unit, and one or more
biocompatible connectors for holding together the graft unit.
[0023] The invention provides a composite bone graft including a
plurality of distinct bone portions, where one or more of the bone
portions are demineralized.
[0024] The invention provides a composite bone graft including a
plurality of distinct bone portions, where one or more of the bone
portions are continuous or discontinuous.
[0025] The invention further provides a composite bone graft
including a plurality of distinct bone portions where one or more
of the bone portions include a discontinuous bone portion, the
discontinuous bone portion including one or more therapeutically
beneficial substances including but not limited to, for example,
one or more of the following: osteoinductive substances,
osteoconductive substances, and pharmaceutically active agents.
Such therapeutically beneficial substances may optionally be
provided with a carrier. Suitable osteoinductive substances include
but are not limited to, for example, autograft bone; allograft
bone; Grafton.TM. produced by Osteotech; DynaGraft.TM.;
demineralized cortical bone; demineralized cancellous bone;
collagen including one or more growth factors including for example
Novus.TM. produced by Stryker Biotech; collagen including
demineralized bone including for example DynaGraft.TM.; cancellous
bone; cortical bone; OpteoForm.TM. produced by the University of
Florida; OsteoFill.TM. produced by the University of Florida; and
growth factors including for example, bone morphogenic protein, and
transforming growth factor-.beta.. Suitable osteoconductive
substances include but are not limited to, for example,
hydroxyapitate; collagen; any biocompatible matrix material
including for example, polymeric matrix materials, bioglass,
bioceramics, resorbable Biomaterials; bioabsorbable polymers; a
plastic matrix; stainless steel; titanium;
cobalt-chromium-molybdenum alloy matrix; and substances including
hydroxyapitate, including for example, Osteoset.TM. produced by
Wright Medical. Suitable pharmaceutically active agents include but
are not limited to, for example, growth factors including for
example bone growth factors including for example bone morphogenic
protein, and transforming growth factor-.beta., chemotherapeutic
agents, anti-inflammatory agents, and antibiotics.
[0026] The invention also provides a composite bone graft,
including a first cortical bone portion, a second cortical bone
portion, a cancellous bone portion disposed between the first
cortical bone portion and the second cortical bone portion to form
a graft unit, and one or more biocompatible connectors for holding
together the graft unit, where the cancellous bone portion is
demineralized and discontinuous.
[0027] The invention provides a composite bone graft, including a
first cortical bone portion, a second cortical bone portion, and a
third cortical bone portion disposed between the first cortical
bone portion and the second cortical bone portion to form a graft
unit, and one or more biocompatible connectors for holding together
the graft unit, where the third cortical bone portion is
demineralized and discontinuous.
[0028] The invention provides a composite bone graft, including a
first cortical bone portion, and a second cortical bone portion
disposed apart from each other, and forming a graft unit, and one
or more biocompatible mechanical connectors for holding together
the graft unit, where the first and second cortical bone portions
are disposed separate from each other by the biocompatible
mechanical connectors, thereby forming a substantially void central
area.
[0029] The invention further provides a composite bone graft
including a substantially void central area, where the
substantially void central area further includes one or more
therapeutically beneficial substances including but not limited to,
for example, one or more of the following: osteoinductive
substances, osteoconductive substances, and pharmaceutically active
agents. Such therapeutically beneficial substances may optionally
be provided with a carrier. Suitable osteoinductive substances
include but are not limited to, for example, autograft bone;
allograft bone; Grafton.TM. produced by Osteotech; DynaGraft.TM.;
demineralized cortical bone; demineralized cancellous bone;
collagen including one or more growth factors including for example
Novus.TM. produced by Stryker Biotech; collagen including
demineralized bone including for example DynaGraft.TM.; cancellous
bone; cortical bone; OpteoForm.TM. produced by the University of
Florida; OsteoFill.TM. produced by the University of Florida; and
growth factors including for example bone morphogenic protein, and
transforming growth factor-.beta.. Suitable osteoconductive
substances include but are not limited to, for example,
hydroxyapitate; collagen; any biocompatible matrix material
including for example, polymeric matrix materials, bioglass,
bioceramics, resorbable Biomaterials; bioabsorbable polymers; a
plastic matrix; stainless steel; titanium;
cobalt-chromium-molybdenum alloy matrix; and substances including
hydroxyapitate, including for example, Osteoset.TM. produced by
Wright Medical. Suitable pharmaceutically active agents include but
are not limited to, for example, growth factors including for
example bone growth factors including for example bone morphogenic
protein, and transforming growth factor-.beta.; chemotherapeutic
agents; anti-inflammatory agents; and antibiotics. The material may
be in any suitable form including for example, in the form of a
solid, sponge, paste, powder, and/or gel.
[0030] The invention further provides a composite bone graft where
the biocompatible connectors include one or more mechanical
biocompatible connectors.
[0031] The invention provides a composite bone graft where the
biocompatible connectors include a chemical biocompatible
connector.
[0032] The invention further provides a composite bone graft where
the mechanical biocompatible connectors include one or more
pins.
[0033] The invention further provides a composite bone graft where
the chemical biocompatible connectors include a biocompatible
adhesive.
[0034] The invention provides a composite bone graft where one or
more biocompatible connectors include one or more of the following:
a mechanical connector and a chemical connector.
[0035] The invention also provides a composite bone graft where the
mechanical biocompatible connectors include one or more of the
following biocompatible materials: cortical bone; stainless steel;
titanium; cobalt-chromium-molybdenum alloy; a bioceramic; a
bioglass; a plastic of one or more of the following: nylon,
polycarbonate, polypropylene, polyacetal, polyethylene, and
polysulfone; and one or more bioabsorbable polymers.
[0036] The invention also provides a composite bone graft where the
mechanical biocompatible connectors include cortical bone.
[0037] The invention provides a composite bone graft where the one
or more pins include one or more cortical bone pins.
[0038] The invention provides a composite bone graft where the
graft unit includes one or more through-holes configured to
accomadate the one or more pins.
[0039] The invention further provides a composite bone graft where
the through-holes are disposed perpendicular to interfaces of bone
portions forming the graft unit.
[0040] The invention further provides a composite bone graft where
the through-holes are disposed perpendicular to interfaces of for
example, the first bone portion, the second bone portion, and the
third bone portion, of the graft unit.
[0041] The invention provides a composite bone graft where the one
or more pins and the one or more through-holes are configured to
provide an interference fit for holding together the graft
unit.
[0042] The invention also provides a composite bone graft where the
one or more through-holes and the one or more pins are round and an
inner diameter of a through-hole is smaller than a diameter of a
pin, to provide an interference fit between the through-hole and
the pin.
[0043] The invention further provides a composite bone graft where
the one or more cortical bone pins include a plurality of vertical
groves provided on a surface thereof.
[0044] The invention further provides a composite bone graft where
the one or more cortical bone pins includes a roughened
surface.
[0045] The invention provides a composite bone graft where the one
or more cortical bone pins further includes a slot extending from
one end of the bone pin.
[0046] The invention provides a composite bone graft where the one
or more pins is threaded to provide a threaded engagement with the
one or more through-holes.
[0047] The invention further provides a composite bone graft where
the one or more pins is threaded and the one or more through-holes
is threaded, to provide a threaded engagement between the one or
more pins and the one or more through-holes.
[0048] The invention provides a composite bone graft where the one
or more pins and the one or more through-holes are configured to
provide a slidable connection, for example, to provide a composite
bone graft including a substantially void central area.
[0049] The invention also provides a composite bone graft where a
cross-section of the one or more pins includes a shape selected
from the group including the following: round, ovoid, square,
rectangular, triangular, pentagon, hexagon, and trapezoidal.
[0050] The invention further provides a composite bone graft
including a plurality of plate-like cortical bone portions, the
cortical bone portions layered to form a graft unit, the graft unit
held together with one or more cortical bone pins.
[0051] The invention further provides a composite bone graft where
the composite bone graft is a cortical cylinder.
[0052] The invention provides a composite bone graft including a
graft unit having one or more through-holes configured to
accomadate one or more pins, the graft unit including two or more
bone portions layered to form the graft unit, and one or more pins
for holding together the graft unit.
[0053] The invention further provides a composite bone graft,
including a graft unit having one or more through-holes configured
to accomadate one or more pins, the graft unit including a first
plate-like cortical bone, a second plate-like cortical bone, a
plate-like cancellous bone disposed between the first plate-like
cortical bone and the second plate-like cortical bone to form the
graft unit, and one or more cortical bone pins for holding together
the graft unit.
[0054] The invention also provides a composite bone graft,
including a graft unit having one or more through-holes configured
to accomadate one or more pins, the graft unit including a first
plate-like bone, a second plate-like bone provided on the first
plate-like bone to form the graft unit, and one or more bone pins
for holding together the graft unit.
[0055] The invention also provides a cervical composite bone graft,
including a flattened curved wedge graft unit having one or more
through-holes configured to accomadate one or more pins, the graft
unit including two or more plate-like cortical bone portions
layered to form the graft unit, and at least two bone pins for
holding together the graft unit, where the graft unit includes a
substantially centrally located through-hole. The diameter of the
through-hole may be readily selected by one of ordinary skill in
the art without undue experimentation depending upon the particular
application; for example, the diameter of the through-hole may be
from about 2.0 mm-4.0 mm; preferably 2.5 mm-3.0 mm; and more
preferably 3.0 mm.
[0056] The invention also provides a composite bone graft where the
one or more through-holes are disposed perpendicular to interfaces
of plate-like bones of the graft unit.
[0057] The invention provides a composite bone graft where the
composite bone graft is a parallelepiped; a parallel block; a
square block; a trapezoid wedge; a cylinder; a tapered cylinder; a
cervical wedge (flattened curved wedge); an ovoid wedge (anterior
lumbar wedge graft) and a polyhedron.
[0058] The invention further provides a composite bone graft where
the composite bone graft is a polyhedron including six planer
surfaces.
[0059] The invention provides a composite bone graft where the
composite bone graft further includes one or more textured
surfaces.
[0060] The invention also provides a composite bone graft where the
one or more textured surfaces includes a plurality of closely
spaced continuous protrusions.
[0061] The invention provides a composite bone graft where the
continuous protrusions include a cross-section having one or more
shapes selected from the following: irregular; triangular, square,
rectangular, and curved.
[0062] The invention further provides a composite bone graft where
the plurality of continuous protrusions are sized to be in a range
of greater than or equal to about 1.5 mm in length; 0.5 to about
10.0 mm in width and 0.1 to about 5.0 mm in depth.
[0063] The invention provides a composite bone graft where the
plurality of closely spaced continuous protrusions are spaced from
about 0.0 to about 3.0 mm apart.
[0064] The invention provides a composite bone graft where the
plurality of protrusions are spaced from about 0.1 to about 2.0 mm
apart.
[0065] The invention also provides a composite bone graft where the
plurality of protrusions are spaced about 0.5 mm apart.
[0066] The invention provides a method for restoring vertical
support of the posterior and/or anterior column by implanting a
composite bone graft including two or more distinct bone portions
held together by one or more connectors, at a site in a
patient.
[0067] The invention provides a composite bone graft containing two
or more connected bone portions, where the composite bone graft has
a plurality of closely spaced protrusions on one or more surfaces
thereof, where the protrusions are continuous protrusions, discrete
protrusions, or a combination thereof.
[0068] The invention provides a composite bone graft where the
plate-like cortical and/or cancellous bone portions are continuous
bone portions and/or discontinuous bone portions.
[0069] The invention provides a composite bone graft including one
or more discontinuous bone portions.
[0070] The invention provides a composite bone graft including one
or more discontinuous, demineralized cortical bone portions.
[0071] The invention provides a composite bone graft including one
or more discontinuous, demineralized cancellous bone portions.
[0072] The invention further provides a composite bone graft where
one or more continuous or discontinuous cancellous bone portions,
(continuous or discontinuous and/or demineralized) includes one or
more therapeutically beneficial substances including but not
limited to, for example, one or more of the following:
osteoinductive substances, osteoconductive substances, and
pharmaceutically active agents. Such therapeutically beneficial
substances may optionally be provided with a carrier. Suitable
osteoinductive substances include but are not limited to, for
example, autograft bone; allograft bone; Grafton.TM. produced by
Osteotech; DynaGraft.TM.; demineralized cortical bone;
demineralized cancellous bone; collagen including one or more
growth factors including for example Novus.TM. produced by Stryker
Biotech; collagen including demineralized bone including for
example DynaGraft.TM.; cancellous bone; cortical bone;
OpteoForm.TM. produced by the University of Florida; OsteoFill.TM.
produced by the University of Florida; and growth factors including
for example bone morphogenic protein, and transforming growth
factor-.beta.. Suitable osteoconductive substances include but are
not limited to, for example, hydroxyapitate; collagen; any
biocompatible matrix material including for example, polymeric
matrix materials, bioglass, bioceramics, resorbable Biomaterials;
bioabsorbable polymers; a plastic matrix; stainless steel;
titanium; cobalt-chromium-molybdenum alloy matrix; and substances
including hydroxyapitate, including for example, Osteoset.TM.
produced by Wright Medical. Suitable pharmaceutically active agents
include but are not limited to, for example, growth factors
including for example bone growth factors including for example
bone morphogenic protein, and transforming growth factor-.beta.;
chemotherapeutic agents; anti-inflammatory agents; and
antibiotics.
[0073] The invention provides a composite bone graft where one or
more continuous or discontinuous cancellous bone portions are
demineralized and include one or more therapeutically beneficial
substances.
[0074] The invention provides a composite bone graft where one or
more discontinuous cortical bone portions, include one or more
therapeutically beneficial substances.
[0075] The invention further provides a composite bone graft where
one or more discontinuous cortical bone portions are demineralized
and include one or more therapeutically beneficial substances.
[0076] The invention also provides a composite bone graft including
a two or more distinct bone portions held together by one or more
connectors, where the composite bone graft includes two
diametrically opposing chamfered edges, one provided along the
length of the graft at its top edge and the other provided along
the length of the graft at its bottom edge, such that the chamfered
edges are diametrically opposing.
[0077] The invention further provides a composite bone graft
including two or more distinct interlocking cortical bone
portions.
[0078] The invention provides a composite bone graft including two
or more distinct interlocking bone portions, where the interlocking
bone portions are self-locking.
[0079] The invention also provides a composite bone graft including
two or more distinct interlocking bone portions, where the
interlocking bone portions are locked with one or more locking
pins.
[0080] The invention further provides a composite bone graft where
bone portions are locked with one or more locking pins entirely or
partially traversing a dimension of the composite bone graft.
[0081] The invention provides an interlocking composite bone graft
where each complementary bone portion is provided with a discrete
or continuous interlocking pattern.
[0082] The invention also provides an interlocking composite bone
graft including two or more distinct adjacent bone portions where
adjacent bone portions are configured to interlock with each other,
and one or more bone pins partially or entirely traversing a
dimension of the graft, where the dimension of the graft is the
length, width, or height of the graft.
[0083] The invention provides an interlocking composite bone graft
including two or more distinct adjacent bone portions where
adjacent bone portions are configured to interlock with each
other.
[0084] The invention provides a composite bone graft including two
or more distinct adjacent interlocking bone portions where adjacent
bone portions include complementary peg-like protrusions and
corresponding depressions, such that the protrusions and
depressions provide an interlocking fit between the bone
portions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0085] FIG. 1 illustrates a perspective view of a trapezoid wedge
composite bone graft having a non-textured surface.
[0086] FIG. 2 illustrates a side view of a trapezoid wedge
composite bone graft having opposing textured surfaces provided
perpendicular to the interfaces of the bone portions. The textured
surfaces illustrate continuous linear protrusions defining a
saw-tooth-like pattern.
[0087] FIG. 3 illustrates a cross-section posterior view of the
trapezoid wedge composite bone graft of FIG. 2.
[0088] FIG. 4 illustrates a cross-section anterior view of the
trapezoid wedge composite bone graft of FIG. 2.
[0089] FIG. 5 illustrates a top view of the trapezoid wedge
composite bone graft of FIG. 2, and having a textured surface.
[0090] FIG. 6 is a perspective view of the trapezoid wedge
composite bone graft of FIG. 2, and having a textured surface.
[0091] FIG. 7 illustrates a perspective of a preferred slidably
connected composite bone graft having a first cortical bone
portion, a second cortical bone portion, cortical bone pins,
through-holes, and a centrally located void.
[0092] FIG. 8 illustrates a top view of the slidably connected
composite bone graft of FIG. 7, having a first cortical bone
portion, a second cortical bone portion, and a cancellous bone
portion disposed there between.
[0093] FIG. 9 illustrates a perspective view of a preferred
embodiment of the composite bone graft.
[0094] FIG. 10 illustrates a preferred cortical dowel composite
bone graft including a plurality of cortical bone portions
connected by a single cortical bone pin inserted into a
through-hole.
[0095] FIG. 11A illustrates the method of making a preferred
embodiment of the composite bone graft.
[0096] FIG. 11B illustrates a method for producing bone pins and
producing a pinned graft unit.
[0097] FIG. 12 illustrates another method for making a composite
bone graft.
[0098] FIG. 13A is a perspective view of a preferred trapezoid
block composite bone graft having opposing textured surfaces; FIG.
13B is a detail of the protrusions of the textured surface.
[0099] FIGS. 14A, 14B and 14C, illustrate a cervical wedge
(flattened curved wedge) composite bone graft for use in cervical
fusions where 14A is a perspective standing view, 14B is a side
view, and 14C is a perspective view where the graft is provided
with opposing textured surfaces.
[0100] FIG. 15 illustrates a method for making a cervical wedge
composite bone graft for use in cervical fusions.
[0101] FIG. 16 illustrates a perspective view of a mechanical pin
connector having a slot extending from its lower end.
[0102] FIG. 17 illustrates a side view of the mechanical pin
connector of FIG. 16, having a slot extending from its lower
end.
[0103] FIG. 18 illustrates a cross-section view of the mechanical
pin connector of FIG. 16, having a slot extending from its lower
end.
[0104] FIG. 19 illustrates a perspective view of a mechanical pin
connector having a plurality of horizontally disposed grooves.
[0105] FIG. 20 illustrates a perspective view of a mechanical pin
connector having helical threads.
[0106] FIG. 21 illustrates a perspective view of a mechanical pin
connector having a plurality of vertically disposed grooves.
[0107] FIG. 22 illustrates a perspective view of a mechanical
slotted pin connector.
[0108] FIG. 23 illustrates a perspective view of a mechanical pin
connector having a plurality of horizontally disposed ridges.
[0109] FIG. 24 illustrates a perspective view of a mechanical
triangular pin connector.
[0110] FIG. 25 illustrates a perspective view of a mechanical
square pin connector
[0111] FIG. 26 illustrates a perspective view of a mechanical
hexagon pin connector.
[0112] FIG. 27 illustrates a perspective view of a rectangular
block composite bone graft having a demineralized cortical bone
portion sandwiched between two cortical bone portions, where the
demineralized cortical bone portion is provided with perforations
and channels, and where the composite graft includes opposing
textured surfaces provided perpendicular to the interfaces of the
bone portions. The textured surfaces illustrate continuous linear
protrusions defining a saw-tooth-like pattern.
[0113] FIG. 28 illustrates a perspective view of a rectangular
block composite bone graft having a demineralized cancellous bone
portion sandwiched between two cortical bone portions, where the
composite graft includes opposing textured surfaces provided
perpendicular to the interfaces of the bone portions. The textured
surfaces illustrate continuous linear protrusions defining a
saw-tooth-like pattern.
[0114] FIG. 29 illustrates a preferred method of making the bone
graft of FIG. 27.
[0115] FIG. 30 illustrates a preferred method of making the bone
graft of FIG. 28.
[0116] FIG. 31A illustrates a top view of a composite bone graft
including a void disposed between two cortical bone portions where
the void includes one or more therapeutically beneficial
substances. FIG. 31B illustrates a perspective view of a composite
bone graft including a void disposed between two cortical bone
portions where the void includes one or more therapeutically
beneficial substances, and the composite graft includes opposing
textured surfaces.
[0117] FIGS. 32A, 32B, and 32C, illustrate a top view, a
cross-section, and a side view, respectively, of a preferred
parallel block composite bone graft.
[0118] FIGS. 33A, 33B, and 33C, illustrate a top view, a
cross-section, and a side view, respectively, of a preferred
trapezoid wedge composite bone graft.
[0119] FIG. 34 illustrates a perspective view of a preferred
trapezoid wedge composite bone graft having opposing textured
surfaces and having a horizontally disposed channel and vertically
disposed canals.
[0120] FIG. 35A illustrates a standing view of a preferred cervical
wedge composite bone graft for use in cervical fusions, having
horizontally disposed channels and having a centrally located
through-hole including an osteoconductive substance. FIG. 35B
illustrates a side view of the cervical wedge graft of FIG. 35A
including a vertically disposed channel.
[0121] FIGS. 36A, 36B, and 36C, illustrate a cross-section, a top
view, and a side view, respectively, of a preferred trapezoid wedge
composite bone graft.
[0122] FIG. 37 illustrates a standing view of a cervical wedge
(flattened curved wedge) composite bone graft for use in cervical
fusions.
[0123] FIG. 38 illustrates a standing view of a cervical wedge
(flattened curved wedge) composite bone graft for use in cervical
fusions.
[0124] FIG. 39 illustrates a perspective view of a preferred
embodiment of the composite bone graft including two interlocking
cortical bone portions.
[0125] FIG. 40A illustrates a side view of a preferred embodiment
of a cervical wedge composite bone graft including two interlocking
cortical bone portions, and FIG. 40B illustrates a perspective view
of the graft including two interlocking cortical bone portions.
[0126] FIG. 41 illustrates a perspective view of a preferred
trapezoid wedge bone graft including three interlocking cortical
bone portions.
[0127] FIGS. 42A, 42B, & 42C illustrate side views of preferred
composite bone grafts including two interlocking cortical bone
portions where the interlocking interface defines a sawtooth
pattern, a stepped pattern and a lock & key pattern,
respectively.
[0128] FIG. 43 illustrates a standing view of a cervical wedge
(flattened curved wedge) composite bone graft for use in cervical
fusions.
[0129] FIG. 44 illustrates a standing view of a cervical wedge
(flattened curved wedge) composite bone graft for use in cervical
fusions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
I. Definitions
[0130] The below definitions serve to provide a clear and
consistent understanding of the specification and claims, including
the scope to be given such terms.
[0131] Bioabsorbable Polymers.
[0132] By the term "bioabsorbable polymers" is intended for the
purposes of the present invention, bioresorbable, bioabsorbable,
biodegradable, and bioerodible materials that are well known to
those of ordinary skill in the art and are described in
Biomaterials Science--An Introduction to Materials in Medicine,
edited by Ratner, B. D. et al., Academic Press, (1996), and include
for example, the following materials: chitosan; isomorphic
ploy(hexamethylene co-trans-1,4-cyclohexane dimethylene oxalates);
poly(glycolic acid); copolymers of poly(glycolic acid) and
poly(lactic acid); polydioxanone; poly(latic acid); polymers having
a back-bone structure selected from the group consisting of:
polyanhydrides, polyphophazenes, polyphosphonates, polyamides, and
polyiminocarbonates; polyhydroxybutyrate; polyhydroxyvalerate;
copolymers of polyhydroxybutyrate and polyhydroxyvalerate;
polycaprolactone; polydioxanone; poly(.gamma.-ethyl glutamate);
poly (DTH iminocarbonate); poly(Bisphenol A iminocarbonate);
poly(DETOSU-1,6 HD-t-CDM ortho ester); poly(Sebacic
acid-hexadecandioic acid anhydride); poly(ortho esters); poly(amino
acids); and PLOA. Such polymers may optionally include one or more
pharmaceutically active agents for controlled release applications,
such agents including for example: osteoinductive factors including
for example bone morphogenic protein; growth factors including for
example transforming growth factor-.beta.; chemotherapeutic agents;
antiobiotics; and anti-inflammatory agents.
[0133] Biocompatible.
[0134] By the term "biocompatible" is intended for the purposes of
the present invention, any material which when implanted in a
patient does not provoke an adverse response in the patient. A
suitable biocompatible material when introduced into a patient is
not toxic or injurious to that patient, or does not cause
immunological rejection.
[0135] Biomechanical Strength.
[0136] By the term "biomechanical strength" is intended for the
purposes of the present invention, those properties exhibited by a
bone graft, including loading strength, compressive strength, and
tensile strength.
[0137] Bone.
[0138] By the term "bone" is intended for the purposes of the
present invention, bone recovered from any source including animal
and human, for example, human bone recovered for the production of
allografts, and animal bone recovered for the production of
xenografts, such allografts and xenografts suitable for
implantation into a human. Such bone includes: any bone or portion
thereof, including cut pieces of bone, including cortical and/or
cancellous bone, for example, recovered from a human including a
living human or a cadaver, or animal, and processed for
implantation into a living patient. Such bones including for
example: the humorous, hemi-pelvi, tibia, fibula, radius, ulna,
rib, vertebrae, mandibular, femur, and ilia, and any cut portion
thereof. Such bone may be demineralized or not demineralized. In a
preferred embodiment a cancellous or cortical bone section is
demineralized and disposed between two non-demineralized cortical
bone portions. Suitable bone may also include continuous or
discontinuous bone portions. For example, one or more bone portions
of a composite bone graft may be discontinuous, for example, a bone
portion may be perforated and demineralized, for example perforated
either before or after demineralization, for example, to allow for
uniform demineralization (perforations before demineralization) and
to promote ingrowth of patient bone. Cancellous and/or
demineralized cancellous and/or discontinuous cancellous and/or
demineralized discontinuous cancellous and or discontinuous
cortical and/or demineralized discontinuous cortical, bone, may
optionally include one or more therapeutically beneficial
substances provided with or without a carrier. transforming growth
factor-.beta.; The composite bone graft may include a substantially
void central area, where the substantially void central area
further includes one or more therapeutically beneficial substances
provided with or without a carrier. The material may be in any
suitable form including for example, in the form of a solid,
sponge, paste and/or gel.
[0139] Bone Marrow Elements.
[0140] By the term "bone marrow elements" is intended for the
purposes of the present invention, the highly cellular
hematopoietic connective tissue filling the medullary cavities and
spongy epiphysis of bones which may harbor bacterial and/or viral
particles and/or fungal particles, and includes for example, blood
and lipid.
[0141] Chamfer.
[0142] By the term "chamfer" is intended for the purposes of the
invention, an oblique face formed at a corner of a composite bone
graft, at an angle to the adjacent principal faces. Suitable angles
include angles in the range of from 38.degree. to 52.degree., more
preferably 40.degree. to 50.degree., even more preferably
42.degree. to 48.degree., and most preferably about 45.degree..
[0143] Cleaned Bone.
[0144] By the term "cleaned bone" is intended for the purposes of
the present invention, a bone or cut portion thereof, that has been
processed using means known in the art, to remove bone marrow
elements.
[0145] Closely Spaced.
[0146] By the term "closely spaced" is intended for the purposes of
the present invention, protrusions (discrete or continuous) which
are in close proximity to each other. Preferably the protrusions
are spaced no more than 3.0 mm apart (i.e. the distance between the
edges of two adjacent protrusions), more preferably no more than
2.0 mm apart, even more preferably no more than 1.5 mm apart, and
most preferably about 0.5 mm apart
[0147] Composite.
[0148] By the term "composite" is intended for the purposes of the
present invention, a bone graft which is made up of two or more
distinct bone portions.
[0149] Connector.
[0150] By the term "connector" is intended for the purposes of the
present invention, a means of connecting two or more distinct bone
portions, including for example a chemical and/or mechanical means.
By the term "mechanical connector" is intended for the purposes of
the present invention, a structural member including for example, a
pin. By the term "chemical connector" is intended for the purposes
of the present invention, a biocompatible composition including for
example, one or more biocompatible adhesives and one or more
surface modification agents and methods.
[0151] Continuous Bone Portion.
[0152] By the term "continuous bone portion" is intended for the
purposes of the present invention, a bone portion that is
substantially solid without any artificial void areas.
[0153] Continuous Protrusion.
[0154] By the term "continuous protrusion" is intended for the
purposes of the present invention, a protrusion whose length
continues substantially uninterrupted, including for example a
linear or curved protrusion whose length is at least three times
greater than its width, preferably at least five times greater, and
includes for example a continuous, protruding concentric ring, and
a continuous linear protrusion, for example, as illustrated in FIG.
2. Each continuous protrusion may or may not be distinct from
another continuous protrusion.
[0155] Demineralized Bone.
[0156] By the term "demineralized bone" is intended for the
purposes of this invention, one or more distinct bone portions
which have been demineralized by any method well known to those of
ordinary skill in the art. Cortical bone is preferably
demineralized in 0.5 to 0.6 N hydrochloric acid for a period of
time of from about 1 to about 8 hours, more preferably for a time
period of about two hours, at 25.degree. C. to 50.degree. C., more
preferably at 25.degree. C. to 37.degree. C. Cancellous bone is
preferably demineralized in 0.5 to 0.6N hydrochloric acid for a
period of time of from about 20 minutes to about 6.0 hours, more
preferably for a time period of from about 30 minutes to about 2.0
hours. Preferably, cortical and/or cancellous bone is demineralized
to contain less than 10 wt % residual calcium, more preferably
about less than 5 wt % residual calcium, even more preferably about
1 wt % to about 3 wt %, and most preferably about 2 wt % residual
calcium. Other methods for demineralizing bone are well known in
the art to which the present invention pertains, and can be readily
selected and employed by one of ordinary skill in the art, without
undue experimentation.
[0157] Discontinuous Bone Portion.
[0158] By the term "discontinuous bone portion" is intended for the
purposes of the present invention, a bone portion that contains
artificially created void areas including for example, a perforated
bone portion, where the perforations or channels may be of any
shape and may partially or completely transverse the bone portion.
Such perforations may be randomly disposed or disposed in a regular
pattern on and/or through the bone portion. Suitable perforations
include perforations traversing the width of the bone portion
provided perpendicular to the interfaces of the bone portions of
the composite graft, and channels traversing the height of the bone
portion provided parallel to the interfaces of the bone portions of
the composite graft. Such perforations allow for uniform
demineralization of a bone portion, and allow for ingrowth of
patient bone. A demineralized discontinuous bone portion may be
perforated prior to demineralization or after demineralization.
[0159] Discrete Protrusion.
[0160] By the term "discrete protrusion" is intended for the
purposes of the present invention, a protrusion which is
discontinuous, i.e. which has a distinct length and width, where
each discrete protrusion is separate and distinct from every other
discrete protrusion, and includes for example a protrusion whose
length is less than three times its width, preferably less than
twice its width and more preferably a protrusion whose length is
about equal to its width.
[0161] Interlocking.
[0162] By the term "interlocking" is intended for the purposes of
the present invention, any pattern provided on a bone portion which
allows that bone portion to engage or interlace with another bone
portion, such that the engaged bone portions act as a single bone
portion when stressed. Such bone portions may be provided with
engaging patterns including but not limited to the following: step
patterns, sawtooth patterns, and ridged patterns, patterns that
define mortise and tenon joints, and lock and key type patterns.
These patterns may be either discrete, for example one bone portion
may include one or more protrusions and a complementary bone
portion may be provided with one or more corresponding depressions,
or continuous, for example bone portions are provided with
complementary continuous grooves (See FIGS. 39, 40, and 41). The
discrete patterns, may include protrusions and corresponding
depressions of any shape and size sufficient to provide an
interlocking fit, and include round, square, rectangular,
triangular, oval, irregular, and any combination of geometric and
curved shaped protrusions and corresponding depressions. The
depth/height of the discrete or continuous patterns is from about
0.1 mm to about 3.5 mm, preferably from about 0.2 mm to about 2.0
mm, more preferably from about 0.3 mm to 1.5 mm, and most
preferably from about 0.5 mm to about 1.0 mm. One of ordinary skill
in the art to which the invention pertain can readily determine,
select and employ an appropriate depth/height of the
depression/protrusion based on the desired graft dimensions,
whether or not a pin will also be used, clinical application, etc.,
without undue experimentation. Adjacent bone portions provided with
interlocking patterns, may be self-locking such that no other
connecting means, for example one or more pins, is necessary to
form a unitary structure, ie. to hold the composite bone graft
together. Alternatively, interlocking bone portions may be "locked"
to form a unitary structure using other connection means, for
example, one or more pins partially or entirely traversing a
dimension of the composite bone graft, where the dimension is for
example the height, width, or length of the composite bone
graft.
[0163] Load-Bearing.
[0164] By the term "load-bearing" is intended for the purposes of
the present invention a non-demineralized bone product for
implantation in a patient at a site where the bone graft will be
expected to withstand some level of physical load(s).
[0165] Locking Pin.
[0166] By the term "locking-pin" is intended for the purposes of
the present invention; one or more pins entirely or partially
traversing a dimension of a composite bone graft which serve to
hold the bone graft together, for example, two or more interlocking
bone portions provided with complementary patterns for example, a
stepped pattern, may be locked using one or more pins, for example,
one bone pin partially traversing the length of the graft.
[0167] Mechanical Strength.
[0168] By the term "mechanical strength" is intended for the
purposes of the present invention, the ability of a bone allograft
to withstand mechanical loads at an implant site without
failing.
[0169] Materials Properties.
[0170] By the term "materials properties" is intended for the
purposes of the present invention, those properties present in
normal fresh bone and include loading strength, compressive
strength, tensile strength, and brittleness.
[0171] Normal Bone.
[0172] By the term "normal bone" is intended for the purposes of
the present invention, fresh hydrated autogenous and/or
fresh-frozen hydrated allograft bone tissue.
[0173] Osteoconductivity.
[0174] By the term "osteoconductivity" is intended for the purposes
of the present invention, the ability of a substance which by its
presence conducts osteoinductive activity. Suitable osteoconductive
materials include but are not limited to, for example, one or more
biocompatible matrix materials. Suitable osteoconductive substances
include but are not limited to, for example, hydroxyapitate;
collagen; any biocompatible matrix material including for example,
polymeric matrix materials, bioglass, bioceramics, resorbable
Biomaterials, bioabsorbable polymers, a plastic matrix, stainless
steel, titanium, and cobalt-chromium-molybdenum alloy matrix; and
substances including hydroxyapitate, including for example,
Osteoset.TM. produced by Wright Medical.
[0175] Osteoinductivity.
[0176] By the term "osteoinductivity" is intended for the purposes
of the present invention, the ability of a substance to promote
bone growth. Suitable osteoinductive substances include but are not
limited to, for example, autograft bone; allograft bone;
Grafton.TM. produced by Osteotech; DynaGraft.TM.; demineralized
cortical bone; demineralized cancellous bone; collagen including
one or more growth factors including for example Novus.TM. produced
by Stryker Biotech; collagen including demineralized bone including
for example DynaGraft.TM.; cancellous bone; cortical bone;
OpteoForm.TM. produced by the University of Florida; OsteoFill.TM.
produced by the University of Florida; growth factors including for
example, bone morphogenic protein and transforming growth
factor-.beta.. Preferably, when a demineralized bone product is
used the bone is demineralized to contain less than 6 wt % residual
calcium, more preferably demineralized to contain 1 wt % to about 3
wt % residual calcium, and most preferably demineralized to contain
about 2 wt % residual calcium.
[0177] Parallelepiped.
[0178] By the term "parallelepiped" is intended for the purposes of
the present invention, a six-faced polyhedron all of whose faces
are parallelograms lying in pairs of parallel planes.
[0179] Polyhedron.
[0180] By the term "polyhedron" is intended for the purposes of the
present invention, a solid formed by plane faces, preferably formed
by six faces.
[0181] Protrusion.
[0182] By the term "protrusion" is intended for the purposes of the
present invention, an irregularity in a surface of a bone allograft
having a height of from 0.1 to 5.00 mm, preferably 0.3 to 3.0 mm,
more preferably 0.5 to 1.5 mm, and most preferably 0.75 mm to 1.2
mm. The protrusions can be discrete, continuous, or a combination
thereof, and can be of any shape including for example: irregular;
pyrimidal; conical; cuboidal; rectangular; and cylindrical; or any
combination thereof. Further, a cross-section of a continuous or
discrete protrusion may be of any shape including for example:
irregular; rectangular; square; oval; round; triangular;
trapizoidal; and a regular or irregular curve; or any combination
thereof. The protrusions can be provided on the bone allograft
surface in a regular, symmetric pattern including for example a
linear pattern or in an irregular pattern.
[0183] Self-Locking, Interlocking Pattern.
[0184] By the term "self-locking, interlocking pattern" is intended
for the purposes of the present invention, any complementary
patterns provided on adjacent bone portions which enable the bone
portions: to interlock, act as a unitary structure, and the bone
portions are held together, without the use of any additional
connecting means.
[0185] Stability.
[0186] By the term "stability" is intended for the purposes of the
present invention the ability of the present composite bone graft
to remain at an implantation site without significantly shifting,
rotating, or being extruded.
[0187] Stress.
[0188] By the term "stress" is intended for the purposes of the
present invention, load per unit cross-sectional area.
[0189] Textured.
[0190] By the term "textured" is intended for the purposes of the
present invention, a composite bone graft having one or more
textured surfaces provided on the surface of the composite bone
graft where the surface of the composite bone graft can be any
surface or a portion of any surface including a natural surface
and/or a cut surface. The textured surface preferably includes a
plurality of protrusions provided on the surface or a portion
thereof, the protrusions of a shape including for example,
irregular; pyrimidal; conical; cuboidal; rectangular; trapizoidal;
curved; and cylindrical; or any combination thereof. The
protrusions can be discrete, continuous, or a combination
thereof.
[0191] Therapeutically Beneficial.
[0192] By the term "therapeutically beneficial" is intended any
material which by its action or presence, bring about a therapeutic
result in a patient. Such materials include but are not limited to,
for example, one or more of the following: osteoinductive
substances, osteoconductive substances, and pharmaceutically active
agents. Such therapeutically beneficial substances may optionally
be provided with a carrier. Suitable osteoinductive substances
include but are not limited to, for example, autograft bone;
allograft bone; Grafton.TM. produced by Osteotech; DynaGraft.TM.;
demineralized cortical bone; demineralized cancellous bone;
collagen including one or more growth factors including for example
Novus.TM. produced by Stryker Biotech; collagen including
demineralized bone including for example DynaGraft.TM.; cancellous
bone; cortical bone; OpteoForm.TM. produced by the University of
Florida; OsteoFill.TM. produced by the University of Florida;
growth factors including for example bone morphogenic protein, and
transforming growth factor-.beta.. Suitable osteoconductive
substances include but are not limited to, for example,
hydroxyapitate; collagen; any biocompatible matrix material
including for example, polymeric matrix materials, bioglass,
bioceramics, resorbable Biomaterials; bioabsorbable polymers; a
plastic matrix; stainless steel; titanium;
cobalt-chromium-molybdenum alloy matrix; and substances including
hydroxyapitate, including for example, Osteoset.TM. produced by
Wright Medical. Suitable pharmaceutically active agents include but
are not limited to, for example, growth factors including for
example bone growth factors including for example bone morphogenic
protein, and transforming growth factor-.beta., and transforming
growth factor-.beta.; chemotherapeutic agents; anti-inflammatory
agents; and antibiotics.
II. Procurement and Preliminary Processing of Bone Tissue
[0193] Suitable bone tissue includes bone obtained from any animal
or human source. Preferably, bone graft tissue can be obtained from
the patient himself (autologous bone) or from a cadaver (allograft
bone). When allograft bone tissue is used, it is processed under
strict aseptic conditions in certified clean room operating suites.
The bone tissue is preferably processed to remove all soft tissue,
including marrow and blood, to produce a cleaned bone graft.
Suitable processing methods are well known to those skilled in the
art and can be readily selected and employed by those of ordinary
skill in the art without undue experimentation. Suitable methods
include the methods disclosed in, for example, U.S. Pat. Nos.
5,556,379; 5,820,581; and 5,797,891.
[0194] After processing, the cleaned grafts are packaged under
sterile conditions and stored for latter processing into the
present composite bone allograft, or immediately processed into the
present composite bone allograft followed by appropriate packaging.
The use of fresh-frozen and/or freeze-dried, bone allografts are
preferred.
III. How to Make a Preferred Embodiment of the Composite Bone
Graft
[0195] FIG. 11A illustrates a preferred method 60 of making the
present composite bone graft. A composite bone graft having of any
size necessary for a particular application, can be made using the
preferred method discussed hereafter. A cortical bone shaft 61 is
obtained from a cadaver and is transected into cortical sections 62
having a length 63 of at least 18.0 mm, preferably at least 21.0
mm.
[0196] A cortical section 62 is then first cut to produce a
cortical plank 64, the remaining cortical section 62a is turned and
again cut to produce a second cortical plank, the remaining
cortical plank 62b is again turned and cut into third and fourth
cortical planks 64. The cortical planks 64 are cut to an
appropriate width 65 and thickness 66. The concave surface 64a of
the plank 64 can be smoothed if needed to produce a smoothed plank
67. Opposing edges 67a and 67b can be cut such that the cut
surfaces 67c and 67d are approximately parallel. The cut width 68
should be larger than the final composite bone graft width. More
specifically, cut width 68 is preferably greater than about 12.0
mm.
[0197] The convex surface 64b of plank 64 is then smoothed to
produce a smoothed plank 69. The smoothed plank 64 is further
smoothed by for example, milling, such that the opposing surfaces
64a and 64b, and 67c and 67d, are parallel, to produce a parallel
plank 70 having a thickness 71 of at least 1.0 mm, preferably from
about 1.5 mm to about 6.0 mm, and more preferably from about 2.0 mm
to about 5.5 mm.
[0198] FIG. 11B illustrates cortical pins 7 cut from a cortical
section 62, using for example a drill press 72 or other means known
in the art. The cortical pins 7, can also be made from a cortical
plank 64, for example by turning on a lathe. The pins 7 have a
diameter of from about 1.0 to about 6.0 mm, preferably from about
1.5 mm to about 4.5 mm, and more preferably from about 2.0 mm to
about 4.0 mm.
[0199] If the composite bone graft includes cancellous bone,
cancellous bone planks 73 are produced and sized by the method as
described above for producing cortical bone planks 69 and 70. The
composite bone unit 74 is then assembled as desired, for example a
cortical parallel plank 70, a cancellous plank 73, and another
cortical parallel plank 70. The composite bone unit 74 has a height
74a, a width 74b and a length 74c. The height 74a, width 74b and
length 74c, can be readily selected by one of ordinary skill in the
art, depending on factors including for example, the particular
application and site of implantation in a patient. The planks are
secured and holes 5 are drilled there through. The through-holes 5
are sized such that a tight or frictional fit is provided between a
pin 7 and a though-hole 5. The cortical pins 7 are then inserted
through the through-holes 5, and pressed to fit if needed, to
produce pinned composite graft 75. The cortical bone pins 7 have a
diameter 8 sufficient to provide an interference fit or frictional
fit between a pin 7 and a through-hole 5. More specifically the
diameter 8 of a cortical pin 7 is generally the same or slightly
larger than the diameter 6 of a through-hole 5 into which it is to
be inserted. The diameter of the pin 7 is preferably no more than
1.5 mm larger than the diameter of the through-hole 5.
[0200] The assembled pinned graft can thereafter be shaped as
desired, for example into a trapezoid shaped graft and
appropriately dimensioned to produce a composite bone graft. One or
more surfaces of the composite bone graft may be textured if
desired, for example, depending upon the particular
application.
[0201] FIG. 12 illustrates an additional method 33 of making a
preferred embodiment of the present composite bone graft. A
cross-section of a femur is obtained from a cadaver, and cleaned
using methods well known to those of ordinary skill in the art to
which the present invention pertains, to remove bone marrow
elements thereby producing the cleaned femural ring 34. The cleaned
femural ring is then sectioned into several sections of cortical
bone including a first cortical bone portion 35 and a second
cortical bone portion 36, each portion having a width 37 of from
about 2.0 to about 10.0 mm; preferably of from about 4.0 to about
8.0 mm; and more preferably of from about 5.0 to about 6.0 mm.
Portions 35 and 36 are then held together to form a graft unit 38
having a width of 39 which is at least 4.0 mm; preferably greater
than 9.0 mm; using for example, a clamp, and one or more
through-holes 5 having a diameter 6 of about 0.5 mm to about 10.0
mm, preferably 2.0 mm to about 5.0 mm, more preferably 2.0 mm to
about 4.0 mm, are then drilled there through.
[0202] Cortical pins 7 are produced from cortical bone by methods
well known to those of ordinary skill in the art to which the
present invention pertains. The pins 7 have a diameter of from 1.0
mm to about 6.0 mm, preferably from about 1.5 mm to about 4.5 mm,
and more preferably from about 2.0 mm to about 4.0 mm. The graft
unit 38, having through-holes 5 drilled there through is then
placed in a press and one or more cortical pins 7 are inserted into
the through-holes 5.
[0203] Thereafter, one or more surfaces 44 of the composite bone
graft 45 can be textured by for example, milling to create a
desired texture including the illustrated continuous linear
protrusions (sawtooth pattern). Preferably, the composite bone
graft includes opposing textured surfaces disposed perpendicular to
the interface(s) of the bone portions.
[0204] FIG. 15 illustrates a preferred method for making a cervical
wedge (flattened curved wedge) composite bone graft. Cortical
planks 70 are produced and pinned using cortical pins 7 as
previously described in FIGS. 11A and 11B to form a pinned cortical
graft unit 89. The pinned graft unit 89 has a height 90, a length
91 and a width 92. The pinned graft unit 89 is then cut and shaped
94 to a designated pattern 93 to form a flattened curved block 95.
A through-hole 83 is then provided centrally through the flattened
curved block 95 using for example a drill press 72. The top 96 and
bottom 97 faces of the block 95 are then provided with a slope at
an angle 98 for example by milling. The top 96 and/or bottom 97
faces may optionally be textured, for example by providing the
faces with a plurality of pyrimidal protrusions.
[0205] FIG. 29 illustrates a method of making a composite bone
graft 99 including a discontinuous, demineralized, cortical bone
portion 100 disposed between two cortical bone portions 70. The
cortical parallel planks 70 are produced as discussed above in
reference to FIG. 11. The discontinuous, demineralized, cortical
bone portion 100 is produced by first producing a cortical parallel
plank 70, as described above in reference to FIG. 11. The cortical
parallel plank 70 is then perforated, for example using a drill
press, to create perforations 101 traversing the width of the
plank, and to create channels 102 traversing the height of the
plank, to produce a discontinuous bone plank 103. The discontinuous
bone plank 103 is then demineralized by any method well known to
those of ordinary skill in the art, including for example,
demineralizing in 0.5-0.6N hydrochloric acid at from 25.degree. C.
to 50.degree. C., preferably at from 25.degree. C. to 37.degree.
C., for a period of time of from about 1 hour to about 8 hours,
preferably for about 2 hours, more preferably demineralization is
carried out until the discontinuous bone plank 103 contains less
than 6 wt % residual calcium, preferably about 1 wt % to about 3 wt
% residual calcium, and most preferably demineralized to contain
about 2 wt % residual calcium, to produce a demineralized
discontinuous plank 100. The demineralized discontinuous bone plank
100 and the cortical parallel planks 70 are then assembled, shaped,
and textured to produce the composite bone graft 99, according to
the methods described in reference to FIG. 11.
[0206] FIG. 30 illustrates a method of making a composite bone
graft 105 including a demineralized cancellous bone portion 106
disposed between two cortical bone portions 70. The cortical
parallel planks 70 are produced as discussed above in reference to
FIG. 11. The demineralized cancellous bone portion 106 is produced
by first producing a cancellous parallel plank 73, as described
above in reference to FIG. 11. The cancellous parallel plank 73 is
then demineralized by any method well known to those of ordinary
skill in the art, including for example, demineralizing in 0.5-0.6N
hydrochloric acid at from 25.degree. C. to 50.degree. C.,
preferably at from 25.degree. C. to 37.degree. C., for a period of
time of from about 20 minutes to about 6.0 hours, preferably for
about 30 minutes to about 2.0 hour to produce a demineralized
cancellous bone plank 106. More preferably, demineralization is
carried out until the bone plank 106 produced, contains less than 6
wt % residual calcium, preferably about 1 wt % to about 3 wt %
residual calcium, and most preferably demineralized to contain
about 2 wt % residual calcium. The demineralized cancellous bone
plank 106 and the cortical parallel planks 70 are then assembled,
shaped, and textured to produce the composite bone graft 105,
according to the methods described in reference to FIG. 11.
[0207] Composite bone grafts including two or more distinct
cortical bone portions each bone portion provided with a pattern
thereon to enable the bone portions to interlock or engage, are
made by first making cortical bone planks as described. After the
planks are made they are each provided with a pattern, for example
a discrete or continuous pattern. The patterned planks are then
fitted together. The patterned planks may be self-locking, ie.
provided with a "key" type pattern, to form a unitary structure, or
may be locked using one or more pins entirely or partially
traversing a dimension, ie. the graft's height, width, and/or
length. Thereafter, the locked graft is shaped to form the
composite bone graft. Suitable patterns include any complementary
patterns which when provided on two or more adjacent bone portions,
enable two or more bone portions to act as one, where the patterns
are self-locking or are locked with one or more additional
connection means, including for example one or more pins.
IV. Description of Preferred Embodiments of the Composite Bone
Graft
[0208] The present composite bone graft provides a bone graft which
can be appropriately sized for any application, has increased
stability of the graft at an implant site and promotes the ingrowth
of patient bone, while providing excellent mechanical strength.
[0209] FIG. 1 illustrates a perspective view of a preferred
composite bone graft 1 including a first cortical bone portion 2, a
second cortical bone portion 4, a cancellous bone portion 3
sandwiched between bone portions 2 and 4, a through-hole 5 having a
diameter 6, and a cortical bone pin 7 having a diameter 8. The
composite bone graft 1, has a length 9, a posterior height 13, an
anterior height 11, a composite width 12, and section widths 10a,
10b, and 10c.
[0210] FIG. 2 illustrates a side view of a composite bone graft 1
having opposing textured surfaces 14a and 14b provided
perpendicular to the interfaces of the bone portions. 14a and 14b
illustrate continuous linear protrusions defining a saw-tooth-like
pattern.
[0211] FIG. 3 illustrates a cross-section posterior view of
composite bone graft 1, illustrating section widths 10a, 10b, and
10c of bone portions 2, 3, and 4, respectively, and having an
anterior height 11 and composite width 12.
[0212] FIG. 4 illustrates a cross-section anterior view of
composite bone graft 1, illustrating an posterior height 13 and
composite width 12.
[0213] FIG. 5 illustrates a top view of composite bone graft 1
illustrating cortical bone portions 2 and 4, cancellous bone
portion 3 disposed there between, and textured surface 14b.
[0214] FIG. 6 is a perspective view of composite bone graft 1
illustrating cortical bone portions 2 and 4, cancellous bone
portion 3 disposed there between, textured surfaces 14a and 14b,
and cortical bone pins 7.
[0215] FIG. 7 illustrates a perspective of a preferred composite
bone graft 15 having a first cortical bone portion 16, a second
cortical bone portion 17, cortical bone pins 18, through-holes 19,
and void 107, where the diameter of the through-holes 19 and the
diameter of the cortical bone pins 18 are configured to allow a
slidable connection between the bone portions 16 and 17, and the
bone portions 16 and 17 and the cortical bone pins 18. The
composite bone graft 15 includes a top textured surface 14b and a
bottom textured surface 14a disposed perpendicular to an interface
between bone portions 16 and 17. Composite bone graft 15 may
optionally include one or more cancellous or cortical bone portions
disposed between and slidably connected to cortical bone portions
16 and 17, and to cortical bone pins 18.
[0216] FIG. 8 illustrates a top view of composite bone graft 15
having a first cortical bone portion 16, a second cortical bone
portion 17, and a cancellous bone portion 20 disposed there
between, with one portions 16, 17, and 20 being slidably connected
with cortical bone pins 19. This graft can be used in place of the
traditional iliac crest wedge.
[0217] FIG. 9 illustrates a perspective view of a preferred
composite bone graft 21 including a first cortical bone portion 22,
a second cortical bone portion 23, a third cortical bone portion
24, through-holes 5 and cortical bone pins 7.
[0218] FIG. 10 illustrates a preferred composite bone graft 25
including a plurality of cortical bone portions including a first
cortical bone portion 26, a second cortical bone portion 27, a
third cortical bone portion 28, a forth cortical bone portion 29, a
fifth cortical bone portion 30, and a single cortical bone pin 31
inserted in through-hole 32. This graft can be used in place of the
traditional cloward dowel.
[0219] FIG. 13A is a perspective view of a preferred trapezoid
block composite bone graft having opposing textured surfaces which
include a plurality of protrusions 80, and having a first cortical
bone portion 2, a second cortical bone portion 4, a cancellous bone
portion 3 sandwiched between bone portions 2 and 4, through-holes
5, and a cortical bone pins 7 having a diameter 8. The composite
bone graft, has a length 9, a posterior height 13, an anterior
height 11, a composite width 12, section widths 10a, 10b, and 10c,
a length 76 which is the length of the graft measured from the
anterior end to the center of the first pin 7, a length 77 which is
the length of the graft measured from the center point of a first
pin 7 to a center point of a second pin 7, and a length 78 which is
the length of the graft measured from a center point of a second
pin to the posterior end of the graft. The textured surface is
detailed in FIG. 13B. The protrusions 80 have a height of 81, and
are cut in a "saw-tooth" pattern at an angle of 79.
[0220] FIGS. 14A, 14B and 14C, illustrate a cervical wedge
composite bone graft (flattened curved wedge composite bone graft)
for use in cervical fusions where 14A is a perspective standing
view, 14B is a side view, and 14C is a perspective view where the
graft is provided with opposing textured surfaces. The flattened
curved wedge composite bone graft includes first and second
cortical bone portions 82 held together by two cortical bone pins 7
to form a pinned graft unit, and the pinned graft unit having a
hole 83 disposed there through located between pins 7. The cervical
fusion graft has a diameter 84, a width 85, an front composite
width 87, and a back composite width 86. The cervical fusion graft
as shown in FIG. 14C has textured opposing faces which include a
plurality of pyrimidal protrusions 88.
[0221] FIG. 16 illustrates a perspective view of a mechanical
connector 46 having a slot 47 extending from its lower end.
[0222] FIG. 17 illustrates a side view of mechanical connector 46
having a slot 47 extending from its lower end.
[0223] FIG. 18 illustrates a cross-section view of mechanical
connector 46 having a slot 47 extending from its lower end.
[0224] FIG. 19 illustrates a perspective view of a mechanical
connector 48 having a plurality of horizontally disposed grooves
49.
[0225] FIG. 20 illustrates a perspective view of a mechanical
connector 50 having helical threads 51.
[0226] FIG. 21 illustrates a perspective view of a mechanical
connector 52 having a plurality of vertically disposed grooves
53.
[0227] FIG. 22 illustrates a perspective view of a mechanical
slotted pin connector 54.
[0228] FIG. 23 illustrates a perspective view of a mechanical
connector 55 having a plurality of horizontally disposed ridges
56.
[0229] FIG. 24 illustrates a perspective view of a mechanical
triangular pin connector 57.
[0230] FIG. 25 illustrates a perspective view of a mechanical
square pin connector 58.
[0231] FIG. 26 illustrates a perspective view of a mechanical
hexagon pin connector 59.
[0232] FIG. 27 illustrates a perspective view of a rectangular
block composite bone graft 99, including a first cortical bone
portion 2, a second cortical bone portion 4, a discontinuous,
demineralized cortical bone portion 104 disposed between cortical
bone portions 2 and 4, where the discontinuous, demineralized
cortical bone portion 100 includes perforations traversing the
width of the bone portion 100 and are disposed perpendicular to the
interfaces of the bone portions 2, 100 and 4, and channels 102
traversing the height of bone portion 100 and are disposed parallel
to the interfaces of the bone portions 2, 100, and 4, through-holes
5, and cortical bone pins 7. The composite bone graft 99 includes
opposing textured surfaces 14a and 14b provided perpendicular to
the interfaces of the bone portions and defining a saw-tooth-like
pattern.
[0233] FIG. 28 illustrates a perspective view of a rectangular
block composite bone graft 105, including a first cortical bone
portion 2, a second cortical bone portion 4, a demineralized
cancellous bone portion 106 disposed between cortical bone portions
2 and 4, through-holes 5, and cortical bone pins 7. The composite
bone graft 105 includes opposing textured surfaces 14a and 14b
provided perpendicular to the interfaces of the bone portions and
defining a saw-tooth-like pattern.
[0234] FIG. 31A illustrates a top view of a rectangular block
composite bone graft 108, including a first cortical bone portion
2, a second cortical bone portion 4, a void 107 disposed between
cortical bone portions 2 and 4, and cortical bone pins 7. The void
107 includes one or more therapeutically beneficial substances
109.
[0235] FIG. 31B illustrates a perspective view of a rectangular
block composite bone graft 108, including a first cortical bone
portion 2, a second cortical bone portion 4, a void 107 disposed
between cortical bone portions 2 and 4, through-holes 5, and
cortical bone pins 7. The void 107 includes one or more
therapeutically beneficial substances 109. The composite bone graft
108 includes opposing textured surfaces 14a and 14b provided
perpendicular to the interfaces of the bone portions 2 and 4, with
the therapeutically beneficial substance 109, and defining a
saw-tooth-like pattern.
[0236] FIGS. 32A, 32B and 32C, illustrate a parallel block
composite bone graft where 32A is a cross-section view, 32B is a
top-view, and 32C is a is a side view of the width of the composite
graft, where the graft is provided with opposing textured surfaces.
The composite bone graft includes first and second cortical bone
units 110, a cancellous bone portion 3 sandwiched between bone
units 110, through-holes 5, and a cortical bone pins 7 (The
diameter of each bone pin may be the same or different depending on
the particular application, implant and size of the graft, the
diameter of a pin is preferably about 1.0 to about 5.0 mm, more
preferably from about 1.5 mm to about 4.0 mm, even more preferably
from about 2.0 to about 3.5 mm, and most preferably 2.5 to 3.0 mm).
The composite bone graft, has a length 9 (preferably from 5.0 to
about 50.0 mm, more preferably from about 10.0 to about 30.0 mm,
even more preferably from about 15.0 mm to about 25.0 mm, and most
preferably about 21.0 mm), a height 112 (preferably from about 3.0
mm to about 30.0 mm, more preferably from about 5.0 mm to about
25.0 mm, even more preferably from about 8.0 mm to about 15.0 mm),
a composite width 12 (preferably from about 4.0 mm to about 20.0
mm, more preferably from about 5.0 mm to about 15.0 mm), section
widths 10a, 10b, and 10e, which are preferably 4.0 mm, 3.0 mm, and
4.0 mm; 4.0 mm, 5.0 mm, and 4.0 mm; and 3.0 mm, 5.0 mm, and 3.0 mm;
respectively, where two bone portions 111 are layered to form the
bone unit 110, and where the width of each bone portion 111 is such
that when layered with another bone portion 111, the resultant
width 113 is as desired, for example, 4.0 mm. The bone graft has a
length 76 (for example when the length of the graft is 21.0 mm,
length 76 is preferably about 7.5 mm) which is the length of the
graft measured from the anterior end to the center of the first pin
7, a length 77 (for example when the length of the graft is 21.0
mm, length 77 is preferably about 8.0 mm) which is the length of
the graft measured from the center point of a first pin 7 to a
center point of a second pin 7, and a length 78 (for example when
the length of the graft is 21.0 mm, length 78 is preferably about
5.5 mm) which is the length of the graft measured from a center
point of a second pin to the posterior end of the graft. The
protrusions 80 have a height of 81 (preferably from about 0.5 mm to
about 2.5 mm, more preferably from about 1.0 mm to about 2.0 mm,
and most preferably from about 1.1 mm to about 1.6 mm), and are cut
in a "saw-tooth" pattern at an angle (preferably about
60.degree.).
[0237] FIGS. 33A, 33B, and 33C, illustrate a trapezoid wedge
composite where 33A is a cross-section view, 33B is a top-view, and
33C is a side view of the width of the composite graft. The
composite bone graft includes first and second cortical bone units
110, a cancellous bone portion 3 sandwiched between bone units 110,
through-holes 5, and a cortical bone pins 7 (The diameter of each
bone pin may be the same or different depending on the particular
application, implant and size of the graft, the diameter of a pin
is preferably about 1.0 to about 5.0 mm, more preferably from about
1.5 to about 4.0 mm, even more preferably from about 2.0 to about
3.5 mm, and most preferably 2.5 to 3.0 mm). The composite bone
graft, has a length 9 (preferably from 5.0 to about 50.0 mm, more
preferably from about 10.0 to about 30.0 mm, even more preferably
from about 15.0 mm to about 25.0 mm, and most preferably about 21.0
mm), an anterior height 11 (preferably from about 3.0 mm to about
30.0 mm, more preferably from about 5.0 mm to about 25.0 mm, even
more preferably from about 8.0 mm to about 15.0 mm), a posterior
height 13 (preferably from about 5.0 mm to about 50.0 mm, more
preferably from about 7.0 mm to about 25.0 mm, and even more
preferably from about 10.0 to about 15.0 mm), a composite width 12
(preferably from about 4.0 mm to about 20.0 mm, more preferably
from about 5.0 mm to about 15.0 mm, section widths 10a, 10b, and
10c, which are preferably 4.0 mm, 3.0 mm, and 4.0 mm; 4.0 mm, 5.0
mm, and 4.0 mm; and 3.0 mm, 5.0 mm, and 3.0 mm; respectively, where
two bone portions 111 are layered to form the bone unit 110, and
where the width of each bone portion 111 is such that when layered
with another bone portion 111, the resultant width 10a or 10c is as
desired, for example, 4.0 mm. The bone graft has a length 76 (for
example when the length of the graft is 21.0 mm, length 76 is
preferably about 7.5 mm) which is the length of the graft measured
from the anterior end to the center of the first pin 7, a length 77
(for example when the length of the graft is 21.0 mm, length 77 is
preferably about 8.0 mm) which is the length of the graft measured
from the center point of a first pin 7 to a center point of a
second pin 7, and a length 78 (for example when the length of the
graft is 21.0 mm, length 78 is preferably about 5.5 mm) which is
the length of the graft measured from a center point of a second
pin to the posterior end of the graft. The protrusions 80 have a
height of 81 (preferably from about 0.5 mm to about 2.5 mm, more
preferably from about 1.0 mm to about 2.0 mm, and most preferably
from about 1.1 mm to about 1.6 mm), and are cut in a "saw-tooth"
pattern at an angle (preferably about 60.degree.).
[0238] FIG. 34 illustrates a trapezoid wedge composite bone graft
113 including a first cortical bone portion 2, a second cortical
bone portion 4, opposing textured surfaces 14a and 14b, vertically
disposed channels 114 (preferably channels 114 have a diameter of
from 0.25 mm to about 5.0 mm, more preferably from about) 0.5 mm to
about 4.0 mm, and most preferably from about 1.0 mm to about 3.0
mm), and horizontally disposed channel 115 (preferably channels 115
have a diameter of from about 0.5 to about 6.0 mm, more preferably
from about 1.0 mm to about 5.0 mm, and most preferably from about
2.0 mm to about 4.0 mm). The composite bone graft also includes
cortical bone pins 7 (preferably bone pins 7 have a diameter of
from about 2.0 mm to about 3.5 mm, more preferably from about 2.5
mm to about 3.0 mm, where each pin may have the same or a different
diameter) and through-holes 5. The channels may optionally include
one or more therapeutically beneficial substances. The graft has a
length 9 (preferably from 5.0 to about 50.0 mm, more preferably
from about 10.0 to about 30.0 mm, even more preferably from about
15.0 mm to about 25.0 mm, and most preferably about 21.0 mm), an
front height 11 (preferably from about 3.0 mm to about 30.0 mm,
more preferably from about 5.0 mm to about 25.0 mm, even more
preferably from about 8.0 mm to about 15.0 mm), a back height 13
(preferably from about 5.0 mm to about 50.0 mm, more preferably
from about 7.0 mm to about 25.0 mm, and even more preferably from
about 10.0 to about 15.0 mm), a composite width 12 (preferably from
about 4.0 mm to about 20.0 mm, more preferably from about 5.0 mm to
about 15.0 mm and most preferably about 6.0 mm to about 8.0 mm),
and a section width 116 (preferably from about 1.0 mm to about 5.0
mm, more preferably from about 2.0 mm to about 4.0 mm, and most
preferably from about 3.0 mm to about 3.5 mm).
[0239] FIG. 35A illustrates a standing view of a cervical wedge
composite bone graft having a textured surface 117a. The cervical
wedge composite bone graft includes first and second cortical bone
portions 82 held together by two cortical bone pins 7 to form a
pinned graft unit, and the pinned graft unit having a through-hole
83 (preferably from about 2.0 mm to about 8.0 mm in diameter, more
preferably from about 3.0 mm to about 5.0 mm) disposed there
through located between pins 7. The cervical fusion graft has a
diameter 84, a width 85, a front composite width 87, and a back
composite width 86. The cervical wedge also includes horizontally
disposed channels 115 (preferably channels 115 have a diameter of
from about 0.5 to about 10.0 mm, more preferably from about 1.0 mm
to about 5.0 mm, and most preferably from about 2.0 mm to about 4.0
mm), and one or more therapeutically beneficial substances 109, for
example cancellous bone or demineralized cancellous bone, disposed
in through-hole 83 and/or channels 115. FIG. 35B illustrates a side
view of the cervical wedge composite bone graft of FIG. 35A and
includes opposing textured surfaces 117a and 117b, and a vertically
disposed channel 118. The top and bottom surfaces of the graft are
sloped at angle 119 and 120, respectively. Angle 119 is preferably
from about 0.degree. to about 10.degree., more preferably from
about 0.degree. to about 7.degree., and in this figure it is
0.degree.. Angle 120 is preferably from about 0.degree. to about
10.degree., more preferably from about 0.degree. to about
7.degree., and in this figure the angle is 7.degree., that is the
graft slopes at 7.degree..
[0240] FIGS. 36A, 36B, and 36C, illustrate a trapezoid wedge
composite bone graft including two cortical bone portions where 36A
is a cross-section view, 36B is a top-view, and 36C is a side view
of the width of the composite graft. The composite bone graft
includes first and second cortical bone portions 2 and 4,
through-holes 5, and a cortical bone pins 7 (The diameter of each
bone pin may be the same or different depending on the particular
application, implant and size of the graft, the diameter of a pin
is preferably about 1.0 to about 5.0 mm, more preferably from about
1.5 to about 4.0 mm, even more preferably from about 2.0 to about
3.5 mm, and most preferably 2.5 to 3.0 mm). The composite bone
graft, has a length 9 (preferably from 5.0 to about 50.0 mm, more
preferably from about 10.0 to about 30.0 mm, even more preferably
from about 15.0 mm to about 25.0 mm, and most preferably about 21.0
mm to 23 mm), an anterior (shorter) height 11 (preferably from
about 3.0 mm to about 30.0 mm, more preferably from about 5.0 mm to
about 25.0 mm, even more preferably from about 8.0 mm to about 15.0
mm), a posterior (longer) height 13 (preferably from about 5.0 mm
to about 50.0 mm, more preferably from about 7.0 mm to about 25.0
mm, and even more preferably from about 10.0 to about 15.0 mm), a
composite width 12 (preferably from about 4.0 mm to about 20.0 mm,
more preferably from about 5.0 mm to about 15.0 mm, section widths
124, which are preferably from about 2.0 mm to about 5.0 mm, more
preferably from about 2.5 mm to about 4.0 mm, and most preferably
about 3.5 mm.+-.0.5 mm. The bone graft has a length 122 (for
example when the length of the graft is 23.0 mm, length 122 is
preferably about 5.5 mm) which is the length of the graft measured
from the posterior (longer) end to the center of the first pin 7, a
length 123 (for example when the length of the graft is 23.0 mm,
length 123 is preferably about 13.5 mm) which is the length of the
graft measured from the posterior (longer) end to the center point
of the second pin 7. The graft is chamfered at diametrically
opposed edges including edge 140 at an angle 125 of preferably
about 45.degree. at a depth 126 of preferably about 0.5 mm. The
wedge graft has a slope 121 of preferably from about 3.0.degree. to
about 13.0.degree., more preferably from about 5.0.degree. to about
11.0.degree., and most preferably about 5.4.degree. or 10.8.degree.
depending on the anterior and posterior heights.
[0241] FIG. 37 illustrates a cross-section view of a cervical wedge
composite bone graft (flattened curved wedge composite bone graft)
for use in cervical fusions. The flattened curved wedge composite
bone graft includes two or more cortical bone portions held
together by two cortical bone pins 7 to form a pinned graft unit,
and the pinned graft unit having a hole 83 disposed there through
located between pins 7 and having a diameter 130 of from about 3.0
mm to about 7.0 mm, more preferably from about 4.0 mm to about 6.0
mm, and most preferably about 4.0 mm to 5.0 mm. The distance 127
between hole 83 and second width 129, and between pins 7 and arc
137, is preferably 1.0 mm to 3.5 mm, more preferably about 1.5 mm
to about 3.0 mm and even more preferably about 2.0 mm. The distance
128 between hole 83 and pins 7 is preferably from 1.5 mm to 3.5 mm,
more preferably from 2.0 mm to about 3.0 mm, and most preferably is
about 2.25 mm to 2.75 mm. The cervical fusion graft has a diameter
84 of from about 10.0 mm to about 20.0 mm, more preferably from
about 12.0 mm to about 16.0 mm, and most preferably about 12.0 mm
to 14.0 mm, a width 85 of from about 14.0 mm to about 24.0 mm, more
preferably from about 15.0 mm to about 20.0 mm, and most preferably
about 15.5 mm to 17.5 mm, and a second width 129 of from about 8.0
mm to about 16.0 mm, more preferably from about 10.0 mm to about
14.0 mm, and most preferably about 11.0 mm to 12.0 mm. Slope 136 is
preferably about 15.degree. to about 30.degree., more preferably
about 20.degree. to about 25.degree., and most preferably about
20.degree..
[0242] FIG. 38 illustrates a cross-section view of a cervical wedge
composite bone graft (flattened curved wedge composite bone graft)
for use in cervical fusions. The flattened curved wedge composite
bone graft includes two or more cortical bone portions held
together by two cortical bone pins 7 to form a pinned graft unit,
and the pinned graft unit having a hole 83 disposed there through
located between pins 7 and hole 83 having a height 131 of from
about 5.0 mm to about 15.0 mm, more preferably from about 6.0 mm to
about 12.0 mm, and most preferably about 8.0 mm to 10.0 mm, and
having a width 130 of from 3.0 mm to about 7.0 mm, more preferably
from about 4.0 mm to about 6.0 mm, and most preferably about 4.0 mm
to 5.0 mm. The distance 127 between hole 83 and second width 129,
and between pins 7 and arc 137, is preferably 1.0 mm to 3.5 mm,
more preferably about 1.5 mm to about 3.0 mm and even more
preferably about 2.0 mm. The distance 128 between hole 83 and pins
7 is preferably from 1.5 mm to 3.5 mm, more preferably from 1.0 mm
to about 3.0 mm, and most preferably is about 2.0 mm. The cervical
fusion graft has a diameter 84 of from about 10.0 mm to about 20.0
mm, more preferably from about 12.0 mm to about 16.0 mm, and most
preferably about 12.0 mm to 14.0 mm, a width 85 of from about 14.0
mm to about 24.0 mm, more preferably from about 15.0 mm to about
20.0 mm, and most preferably about 15.5 mm to 17.5 mm, and a second
width 129 of from about 8.0 mm to about 16.0 mm, more preferably
from about 10.0 mm to about 14.0 mm, and most preferably about 11.0
mm to 12.0 mm. Slope 136 is preferably about 15.degree. to about
30.degree., more preferably about 20.degree. to about 25.degree.,
and most preferably about 20.degree..
[0243] FIG. 39 illustrates a perspective view of a preferred
composite bone graft including cortical bone portions 132, and a
cortical bone pins 7. The cortical bone portions 132 are patterned
with grooves 133 running in direction 135 to provide an
interlocking fit between the bone portions 132.
[0244] FIGS. 40A and 40B illustrate a wedge composite bone graft
(flattened curved wedge composite bone graft) for use in cervical
fusions where 14A is a standing side view, and 14B is a perspective
view. The flattened curved wedge composite bone graft includes
first and second cortical bone portions 132 held together by two
cortical bone pins 7 to form a pinned graft unit, and the pinned
graft unit having a hole 83 disposed there through located between
pins 7. The cortical bone portions 132 are patterned with grooves
133 running in direction 135 to provide an interlocking fit between
the bone portions 132.
[0245] FIG. 41 illustrates a perspective view of a preferred
composite bone graft including cortical bone portions 132 and 134,
and a cortical bone pins 7. The cortical bone portions 132 and 134
are patterned with grooves 133 running in direction 135 to provide
an interlocking fit between the bone portions 132.
[0246] FIGS. 42A, 42B, and 42C illustrate side views of a preferred
composite bone graft including two patterned cortical bone portions
132 having a pattern 133, 138, and 139, respectively, where the
bone portions are interlocked with each other. FIG. 42C illustrates
a self-locking, interlocking pattern 139.
[0247] FIG. 43 illustrates a cross-section view of a cervical wedge
composite bone graft (flattened curved wedge composite bone graft)
for use in cervical fusions. The flattened curved wedge composite
bone graft includes two or more cortical bone portions held
together by two cortical bone pins 7 having a diameter of from 1.0
mm to about 4.0 mm, preferably from about 2.0 mm to about 3.0 mm
and more preferably about 2.5 mm, to form a pinned graft unit, and
the pinned graft unit having a hole 83 disposed there through
located between pins 7, and hole 83 having a width 130 of from 3.0
mm to about 7.0 mm, more preferably from about 4.0 mm to about 6.0
mm, and most preferably about 4.0 mm to 5.0 mm. The distance 127
between hole 83 and second width 129, and between pins 7 and arc
137, is preferably 1.0 mm to 3.5 mm, more preferably about 1.5 mm
to about 3.0 mm and even more preferably about 2.0 mm. The distance
128 between hole 83 and pins 7 is preferably from 1.5 mm to 3.5 mm,
more preferably from 1.0 mm to about 3.0 mm, and most preferably is
about 2.0 mm. The cervical fusion graft has a diameter 84 of from
about 10.0 mm to about 20.0 mm, more preferably from about 12.0 mm
to about 16.0 mm, and most preferably about 11.0 mm to 13.0 mm, a
width 85 of from about 10.0 mm to about 24.0 mm, more preferably
from about 12.0 mm to about 20.0 mm, and most preferably about 13.5
mm to 15.5 mm, and a second width 129 of from about 4.0 mm to about
12.0 mm, more preferably from about 6.6 mm to about 10.0 mm, and
most preferably about 7.0 mm to about 8.0 mm Slope 136 is
preferably about 25.degree..
[0248] FIG. 44 illustrates a cross-section view of a cervical wedge
composite bone graft (flattened curved wedge composite bone graft)
for use in cervical fusions. The flattened curved wedge composite
bone graft includes two or more cortical bone portions held
together by two cortical bone pins 7 having a diameter of from 1.0
mm to about 4.0 mm, preferably from about 2.0 mm to about 3.0 mm
and more preferably about 2.5 mm, to form a pinned graft unit, and
the pinned graft unit having a hole 83 disposed there through
located between pins 7, and hole 83 having a diameter 130 of from
3.0 mm to about 9.0 mm, more preferably from about 4.0 mm to about
8.0 mm, and most preferably about 6.0 mm to 7.0 mm, and a width 141
of from about 5.0 mm to about 13.0 mm, preferably from about 7.0 mm
to about 11.0 mm, more preferably from about 8.5 mm to about 9.5
mm, and most preferably about 9.0 mm. Hole 83 has a second width
140 of from about 2.0 mm to about 6.0 mm, preferably from about 3.0
mm to about 5.0 mm, and more preferably form about 3.5 mm to about
4.5 mm. The distance 127 between hole 83 and second width 129, and
between pins 7 and arc 137, is preferably 1.0 mm to 3.5 mm, more
preferably about 1.5 mm to about 3.0 mm and even more preferably
about 2.0 mm. The cervical fusion graft has a diameter 84 of from
about 10.0 mm to about 20.0 mm, more preferably from about 12.0 mm
to about 16.0 mm, and most preferably about 13.0 mm to 15.0 mm, a
width 85 of from about 10.0 mm to about 24.0 mm, more preferably
from about 12.0 mm to about 20.0 mm, and most preferably about 16.5
mm to 18.5 mm, and a second width 129 of from about 6.0 mm to about
14.0 mm, more preferably from about 8.0 mm to about 12.0 mm, and
most preferably about 9.0 mm to 11.0 mm. Slope 136 is preferably
about 25.degree..
[0249] The present composite bone graft can include two or more
bone portions, including any combination of cancellous and cortical
bone portions, or cancellous or cortical bone portions alone, where
the bone portions may optionally be demineralized, and may
optionally be discontinuous, where the bone portions are connected,
for example by interlocking the bone portions, and/or by one or
more mechanical and/or chemical connectors. Any cancellous bone
portion and/or discontinuous bone portion (cortical and/or
cancellous), and/or any demineralized bone portion (cortical and/or
cancellous) may optionally include one or more pharmaceutically
active agents or therapeutically beneficial substances provided
therein, for example provided in the matrix of cancellous bone, or
provided in any artificially created void areas. Both the cortical
and cancellous bone portions may be solid and continuous or may be
discontinuous (i.e. include one or more "holes" or "perforations"
of any shape disposed at regular or random intervals throughout the
bone portion. Bone portions may be provided with a pattern to
enable an interlocking fit between cortical bone portions.
[0250] Suitable mechanical connectors include pin-type structures
having any cross-section shape, such shapes including for example,
round, square, triangular, rectangular, hexagon, pentagon, oval,
and irregular. The pin-type structure can include surface
modification, for example the surface can be roughened, or provided
with a plurality of horizontally or vertically disposed grooves
(horizontal or vertically relative to the length of the pin);
horizontally or vertically disposed ridges; or helical threads. The
pin or surface-modified pin can also include one or more slots
extending partially or entirely through the diameter of the pin,
and extending partially or entirely through the length of the pin,
suitable slots include for example, a slot extending partially
through the diameter of the pin, for example about half-way through
the diameter of the pin, and through the entire length of the pin;
and a slot extending entirely through the diameter of the pin, and
extending through a partial length of the pin for example,
extending at least half-way through the length of the pin,
preferably extending no more than about seven-eighths the length of
the pin. Suitable mechanical connectors also include cotter pins. A
composite graft can be pinned with one or more biocompatible pins,
where the pins have substantially the same diameter or have a
diameter different from each other. Suitable diameters can be
readily selected and employed by one of ordinary skill in the art
to which the present invention pertains without undue
experimentation depending upon, for example, the particular
application and implantation site, and the size and shape of the
composite graft. The composite graft can be pinned with one or more
biocompatible pins, entirely or partially traversing a dimension of
the graft, for example, the height, length, and/or width of the
composite graft. One of ordinary skill in the art to which the
present invention pertains can readily select an appropriate pin,
number of pins, and determine the orientation of the pin or pins,
based on for example, the particular graft, whether the graft is
interlocking or not, the orientation of the graft in the body, and
the clinical indication, without undue experimentation.
[0251] Suitable chemical connectors include any biocompatible
adhesive. Such adhesives are well known to those of ordinary skill
in the art to which the present invention pertains, and can be
readily selected and employed by those of ordinary skill in the
art, without undue experimentation. Suitable chemical connectors
also include known methods of biochemical surface modification.
Such methods are well known to those of ordinary skill in the art
to which the present invention pertains, and can be readily
selected and employed by those of ordinary skill in the art,
without undue experimentation.
[0252] The chemical and/or mechanical connectors may be used alone
or in any combination and may include one or more therapeutically
beneficial substances including for example, one or more
osteoinductive substances, one or more osteoconductive substances
and one or more pharmaceutically active agents.
[0253] The through-hole(s) of the composite bone graft may also
include surface modification as described above for the present
mechanical connectors configured to accomadate a particular
mechanical connector. For example, if a threaded cortical bone pin
is used, the through-hole or holes can optionally be threaded. The
through-hole(s) can traverse any dimension of the graft, provided
that they are placed such that when graft unit is connected the
graft is held together. One of ordinary skill in the art to which
the present invention pertains can readily select an optimum
location for the through-holes based on criteria including the
following: the anterior and posterior height of the composite bone
graft, and the diameter of the mechanical and/or mechanical and
chemical connectors, and the height of the protrusions. For
example, when the anterior height is relatively small (i.e. 7.0 mm)
and the diameter of the pin is relatively large (i.e. 2.5-3.0 mm),
the through-holes can be spaced equidistant along the length of the
graft unit, or displaced toward the posterior end of the graft
unit.
[0254] The graft unit can be connected with one or more mechanical
connectors. Suitable connection include any connection which is
adequate to hold the bone portions of the graft unit together. Such
connections include, for example, an interference or friction
connection where the diameter of the pin is the same as or slightly
larger than (preferably no more than 1.5 mm larger than the
diameter of the through-hole) the diameter of the corresponding
through-hole; a slidable connection where the diameter of the pin
is the slightly less than the diameter of the through-hole, and a
compression fit, where the pin is configured to allow compression
upon insertion where the pin expands after insertion, achieved for
example, by providing the pin with a slot.
[0255] The mechanical connector of the invention, including
pin-like connectors can be composed of any biocompatible material
sufficient to hold together the present graft unit. Suitable
biocompatible materials include for example, cortical bone;
stainless steel; titanium; cobalt-chromium-molybdenum alloy; and a
plastic for example, of one or more of the following: nylon,
polycarbonate, polypropylene, polyacetal, polyethylene, and
polysulfone, where the plastic can optionally include fibers; and a
polymer including one or more bioabsorbable polymers including
resorbable calcium phosphates; bioceramics and/or glasses including
for example bioactive glasses and glass-ceramics; and calcium
phosphate ceramics. Such mechanical connectors including for
example, bioabsorbable polymers may optionally include one or more
active agents, including for example one or more pharmaceutically
active agents and/or one or more therapeutically beneficial agents,
provided on the surface or impregnated in the matrix of the
material.
[0256] The surface of the mechanical connector can be modified by
methods well known to those of ordinary skill in the art to which
the invention pertains, and include for example the following: (a)
modification to influence cell adhesion and growth, provided by:
(I) oxidized polystyrene surface, (ii) ammonia plasma-treated
surface, and (iii) plasma-deposited acetone or methanol film; (b)
modification to control protein adsorption; and (c) modification to
improve lubricity.
[0257] The composite bone graft preferably has a shape including
for example, a square, rectangular or curved block; a flattened
curved wedge (ie. a cervical wedge for use in cervical fusion); a
wedge; a trapezoid wedge; a polyhedron block, a parallelepiped; a
cylinder or dowel having a uniform diameter or a decreasing or
increasing diameter, for example a tapered cylinder or tapered
dowel; a dowel or tapered dowel having a cross-section of a shape
including for example, round, oval, square, rectangular,
triangular, pentagon, or hexagon.
[0258] The composite bone graft can include one or more partially
or completely textured surfaces. Preferably, a textured composite
bone graft includes opposing textured surfaces disposed
perpendicular to the interface(s) of the bone portions. The
textured surface of the composite bone graft includes a plurality
of protrusions. The protrusions can be formed over an entire
surface of the composite bone graft or over a portion of a surface,
for example over the entire cut surfaces, or over a portion of the
cut surfaces. The plurality of protrusions can be formed on the
surface in any number of ways well known to those of ordinary skill
in the art to which the present invention pertains, including for
example mechanical and/or chemical methods, including for example,
by forming a series of parallel linear or curved grooves. The bone
allograft protrusions can be formed by milling, for example by
milling a set of parallel linear groves to form a saw-tooth
configuration on the cut surface of the composite graft to form
continuous linear protrusions; by milling a first set of parallel
linear groves followed by turning the graft and forming a second
set of parallel grooves at an angle to the first series, for
example, at a 90.degree. angle to form a plurality of discrete
pyrimidal protrusions. Milling is preferably achieved, by for
example: running the graft over a milling tool which includes a
plurality of closely spaced blades which can be adjusted to achieve
a desired height and width; to form the discrete pyrimidal
protrusions, the graft can then be turned at, for example, a
90.degree. angle and again run over the milling tool to produce the
discrete protrusions illustrated. Milling can also be achieved
using for example a routing or dremel tool, a laser, and masking
and acid etching.
[0259] Other protrusions, for example concentric rings or other
curved or irregular, or regular protrusions can be provided by
attaching a drill bit having a blade corresponding to the
protrusion pattern desired where the blade is appropriately sized
to provide a desired protrusion width, length, and height, to a
drill and drilling the desired surface of the bone to achieve the
desired textured surface. One of ordinary skill in the art can
readily design and produce, or select, and employ an appropriate
milling tool to achieve a desired textured surface on a bone
allograft, without undue experimentation.
[0260] Preferably, the protrusions (discrete, continuous, or a
combination thereof) present on one or more surfaces of the present
allograft are closely spaced, preferably from about 0.0 to 3.0 mm
apart, preferably 0.1 to 2.0 mm apart, more preferably about 0.2 to
1.5 mm apart, and most preferably about 0.5 mm apart, (that is,
there is preferably a distance of from 0.0 to 3.0 mm between the
edges of two adjacent protrusions). The protrusions preferably have
a height of from 0.1 to 5.00 mm, preferably 0.3 to 3.0 mm, more
preferably 0.5 to 1.5 mm, and even more preferably 0.75 mm to 1.3
mm, and most preferably about 1.2 mm.
[0261] The composite bone graft may include one or more void areas.
Examples of such grafts include a composite graft having for
example a first and a second cortical bone portion where the bone
portions are for example slidably connected with for example one or
more bone pins, where the first and second bone portion are
disposed apart thereby creating a centrally located void. The void
may optionally include any pharmaceutically active agent and/or
therapeutically beneficial agent, including for example,
osteoinductive substances including for example, bone morphogenic
protein, hydroxyapitate, demineralized bone and bone products
including for example GRAFTON and DYNEGRAFT, and autograft bone;
such substances may be in any form including for example, in the
form of a paste, gel, or sponge.
IV. Use of the Composite Bone Grafts
[0262] The present composite bone grafts are useful in spinal
applications including restoration of column support and are
preferably used from the posterior approach. Composite grafts
suitable for posterior lumbar interbody fusions include for example
the following described in detail below: (a) composite bone grafts
having a trapezoid wedge shape and optionally having opposing
textured surfaces disposed perpendicular to the interfaces of the
bone portions, (b) composite bone grafts having a parallel block
shape and optionally having opposing textured surfaces disposed
perpendicular to the interfaces of the bone portions, (c) composite
bone grafts having a large square block shape and optionally having
opposing textured surfaces disposed perpendicular to the interfaces
of the bone portions, (d) composite bone graft blocks having a
flattened curved wedge shape and optionally having opposing
textured surfaces disposed perpendicular to the interfaces of the
bone portions for use in for example, cervical fusion, (which can
be used from an anterior or posterior approach) and (e) composite
bone grafts having an ovoid wedge shape for performing anterior
fusions (which can be used from an anterior or posterior
approach).
[0263] The term "about" used below and throughout this disclosure
in reference to specific dimensions means that the tolerance limits
for overall or outer dimensions of the composite bone graft is plus
or minus (+/-) 1.0 mm, and the tolerance limits for the width of
individual cortical bone portions is plus or minus (+/-) 0.5
mm.
[0264] The composite bone grafts having a trapezoid wedge shape,
the shape as shown in FIG. 1, and optionally having opposing
textured surfaces disposed perpendicular to the interfaces of the
bone portions, preferably include two or more bone portions where
the bone portions can be cortical or cancellous bone portions or a
combination thereof, each bone portion having a width of from about
1.5 mm to about 10.0 mm, preferably from about 2.0 mm to about 7.0
mm, more preferably from about 2.0 mm to about 5.0 mm, and most
preferably having a width of about 2.0 mm to about 4.0 mm, to give
a composite width of from about 8.0 mm to about 15.0 mm, preferably
from about 9.0 mm to about 13.00 mm, and more preferably about 11.0
mm.
[0265] The trapezoid wedge composite bone graft has a front
(anterior) height which is smaller than its back (posterior)
height, the anterior height being from about 5.0 mm to about 15.0
mm, preferably from about 6.0 mm to about 13.0 mm, more preferably
from about 7.0 mm to about 12.0 mm, and most preferably about 8.0
mm, 9.0 mm, 10.0 mm, 12.0 mm, or 14.0 mm; the posterior height
being from about 7.0 mm to about 20.0 mm, preferably from about 8.0
mm to about 17.0 mm, more preferably from about 9.0 mm to about
15.0 mm, and most preferably the posterior height is about 7.0 mm,
10.0 mm, 11.0 mm, 12.0 mm, or 14.0 mm; and the trapezoid wedge
composite bone graft has a length of from about 15.0 mm to about
35.0 mm, preferably from about 17.0 mm to about 30.0 mm, more
preferably from about 20.0 mm to about 27.0 mm, and most preferably
a length of about 21.0 mm, or 23.0 mm.
[0266] The bone portions may be interlocking and/or connected with
one or more mechanical and/or chemical biocompatible connectors.
The preferred connectors include mechanical connectors including
for example, one or more cortical bone pins having a round
cross-section and having a diameter of from about 1.0 mm to about
6.0 mm, preferably from about 2.0 mm to about 5.0 mm, more
preferably from about 2.0 mm to about 4.5 mm, and most preferably a
pin diameter of from about 2.0 mm to about 4.0 mm, where the
diameter of each pin in a single graft may be the same or
different. The diameter of the two corresponding through-holes is
preferably sufficient to provide an interference or frictional or
slidable connection between the bone portions and the pin,
preferably a interference or frictional connection. The foregoing
described trapezoid wedge composite optionally includes a
cancellous bone portion disposed between the two cortical bone
portions and having the same width or a greater width than the
cortical bone portions. The trapezoid wedge composite graft can
optionally include diametrically opposed chamfered edges.
[0267] Most preferable trapezoid wedge composite bone grafts
include the following configurations:
[0268] (a) a first cortical portion having a width of from about
3.0 mm to about 4.0 mm, preferably about 4.0 mm; a second cortical
bone portion having a width of from about 3.0 mm to about 4.0 mm,
preferably about 4.0 mm; a central cancellous bone portion having a
width of from about 3.0 mm to about 5.0 mm, preferably about 3.0 mm
disposed there between, forming a graft unit, the graft unit held
together by two round cortical bone pins having a diameter of from
about 2.0 mm to about 4.0 mm, the composite graft having an overall
length of about 21.0 mm, an anterior height of about 9.0 mm, and a
posterior height of about 11.0 mm; or an anterior height of about
8.0 mm and a posterior height of about 10.0 mm, or an anterior
height of about 10.0 mm and a posterior height of about 12.0 mm, or
an anterior height of about 12.0 mm and a posterior height of about
14.0 mm.
[0269] (b) a first cortical portion having a width of about 4.0 mm;
a second cortical bone portion having a width of about 4.0 mm; a
central cancellous bone portion having a width of about 3.0 mm
disposed there between forming a graft unit, the graft unit held
together by two round cortical bone pins having a diameter of about
3.0 mm, the composite graft having an overall length of about 21.0
mm, an anterior height of about 9.0 mm, and a posterior height of
about 11.0 mm, or an anterior height of about 8.0 mm and a
posterior height of about 10.0 mm, or an anterior height of about
10.0 mm and a posterior height of about 12.0 mm, or an anterior
height of about 12.0 mm and a posterior height of about 14.0 mm;
and where the length of the graft measured from the posterior end
to the center of the first pin is about 5.5 mm, the length of the
graft measured from the center point of a first pin to a center
point of a second pin is about 8.0 mm and, the length of the graft
measured from a center point of a second pin to the anterior end of
the graft is about 7.5 mm, and optionally having opposing textured
surfaces where the protrusions are in a saw-tooth pattern, and have
a height of about 1.2 mm and have an angle of about 60.degree.
between protrusions;
[0270] (c) a first cortical portion having a width of about 3.0 mm;
a second cortical bone portion having a width of about 3.0 mm; a
central cancellous bone portion having a width of about 3.0 mm
disposed there between forming a graft unit, the graft unit held
together by two round cortical bone pins having a diameter of about
4.0 mm, the composite graft having an overall length of about 21.0
mm, an anterior height of about 7.0 mm, and a posterior height of
about 9.0 mm, or an anterior height of about 8.0 mm and a posterior
height of about 10.0 mm, or an anterior height of about 10.0 mm and
a posterior height of about 12.0 mm, or an anterior height of about
12.0 mm and a posterior height of about 14.0 mm; and where the
length of the graft measured from the posterior end to the center
of the first pin is about 6.0 mm, the length of the graft measured
from the center point of a first pin to a center point of a second
pin is about 9.0 mm and, the length of the graft measured from a
center point of a second pin to the anterior end of the graft is
about 6.0 mm, and optionally having opposing textured surfaces
where the protrusions are in a saw-tooth pattern, and have a height
of about 1.2 mm and have an angle of about 60.degree. between
protrusions;
[0271] (d) a first cortical portion having a width of about 3.0 mm,
a second cortical bone portion having a width of about 3.0 mm, a
central cancellous bone portion having a width of about 5.0 mm
disposed there between, forming a graft unit, the graft unit held
together by two round cortical bone pins having a diameter of about
2.0 mm to about 4.0 mm, the composite graft having an overall
length of about 21.0 mm, an anterior height of about 9.0 mm, and a
posterior height of about 11.0 (e) a first cortical portion having
a width of about 3.0 mm, a second cortical bone portion having a
width of about 3.0 mm, a central cancellous bone portion having a
width of about 7.0 mm disposed there between, forming a graft unit,
the graft unit held together by two round cortical bone pins having
a diameter of about 2.0 mm to about 4.0 mm, the composite graft
having an overall length of about 21.0 mm, an anterior height of
about 11.0 mm, and a posterior height of about 13.0 mm;
[0272] (f) a first cortical portion having a width of about 3.0 mm,
a second cortical bone portion having a width of about 3.0 mm, a
central cancellous bone portion having a width of about 3.0 mm
disposed there between, forming a graft unit, the graft unit held
together by two round cortical bone pins having a diameter of about
2.0 to about 4.0 mm, the composite graft having an overall length
of about 21.0 mm, an anterior height of about 7.0 mm, and a
posterior height of about 9.0 mm;
[0273] (g) a first cortical portion having a width of about 4.0 mm,
a second cortical bone portion having a width of about 4.0 mm
forming a graft unit, the graft unit held together by two round
cortical bone pins having a diameter of about 3.0 mm, the composite
graft having an overall length of about 25.0 mm, an anterior height
of about 12.0 mm, and a posterior height of about 15.0 mm;
[0274] (h) a first, second, third and fourth cortical bone portion
each having a width of from about 2.0 mm to about 3.0 mm,
preferably about 2.0 mm, a first cancellous-bone portion having a
width of from about 2.0 mm to about 3.0 mm, preferably about 3.0
mm, where the first cortical bone portion is disposed on the second
cortical bone portion, the first cancellous bone portion is
disposed between the second and third cortical bone portions, and
the fourth cortical bone portion is disposed on the third cortical
bone portion, Miming a graft unit, the graft unit held together by
two round cortical bone pins having a diameter of about 2.0 mm to
about 4.0 mm, the composite graft having an overall length of about
21.0 mm, an anterior height of about 9.0 mm, a posterior height of
about 11.0 mm, and a composite width of about 11.0 mm;
[0275] (i) a combination of at least two cortical bone portions
optionally having a cancellous bone portion disposed therebetween,
and having: (1) a posterior height of 9.0 mm an anterior height of
7.0 mm, a length of 21.0 mm, and a composite width of 12.0 mm; (2)
a posterior height of 9.0 mm an anterior height of 7.0 mm, a length
of 25.0 mm, and a composite width of 12.0 mm; (3) a posterior
height of 11.0 mm, an anterior height of 9.0 mm, a length of 23.0
mm, and a composite width of 12.0 mm; (4) a posterior height of
11.0 mm, an anterior height of 9.0 mm, a length of 25.0 mm, and a
composite width of 12.0 mm; (5) a posterior height of 13.0 mm, an
anterior height of 11.0 mm, a length of 25.0 mm, and a composite
width of 12.0 mm; and (6) a posterior height of 15.0 mm, an
anterior height of 13.0 mm, a length of 25.0 mm, and a composite
width of 12.0 mm; and
[0276] (j) a combination of two or more cortical bone portions
optionally each having a patterned surface such that an
interlocking fit between the bone portions is provided, and having:
(1) a posterior height of 14.0 mm an anterior height of 10.0 mm, a
length of 21.0 mm, and a composite width of 7.0 mm, two cortical
bone pins each having a diameter of 3.0 mm, and a slope of
10.8.degree., and having diametrically opposed chamfered edges at
45.degree. and 0.5 mm in depth, a distance from the center of the
first pin to the center point of the second pin of 8.0 mm, and a
distance from the anterior end of the graft to the center point of
the first pin of 7.5 mm; (2) a posterior height of 12.0 mm an
anterior height of 10.0 mm, a length of 21.0 mm, and a composite
width of 7.0 mm, two cortical bone pins each having a diameter of
3.0 mm, and a slope of 5.45.degree., having diametrically opposed
chamfered edges at 45.degree. and 0.5 mm in depth, a distance from
the center of the first pin to the second of the second pin of 8.0
mm, and a distance from the anterior end of the graft to the center
point of the first pin of 7.5 mm; (3) a posterior height of 14.0 mm
an anterior height of 12.0 mm, a length of 21.0 mm, and a composite
width of 7.0 mm, two cortical bone pins each having a diameter of
3.0 mm, and a slope of 5.45.degree., having diametrically opposed
chamfered edges at 45.degree. and 0.5 mm in depth, a distance from
the center of the first pin to the second of the second pin of 8.0
mm, and a distance from the anterior end of the graft to the center
point of the first pin of 7.5 mm; (4) a posterior height of 11.0
mm, an anterior height of 9.0 mm, a length of 25.0 mm, and a
composite width of 12.0 mm; (5) a posterior height of 12.0 mm an
anterior height of 9.8 mm, a length of 23.0 mm, and a composite
width of 7.0 mm, two cortical bone pins each having a diameter of
3.0 mm, and a slope of 5.5.degree., having diametrically opposed
chamfered edges at 45.degree. and 0.5 mm in depth, a distance from
the center point of the second pin to the posterior end of the
graft of 13.5 mm, and a distance from the center point of the first
pin to the posterior end of the graft 5.5 mm; (6) a posterior
height of 14.0 mm an anterior height of 9.8 mm, a length of 23.0
mm, and a composite width of 7.0 mm, two cortical bone pins each
having a diameter of 3.0 mm, and a slope of 10.8.degree., having
diametrically opposed chamfered edges at 45.degree. and 0.5 mm in
depth, a distance from the center point of the second pin to the
posterior end of the graft of 13.5 mm, and a distance from the
center point of the first pin to the posterior end of the graft 5.5
mm; (7) a posterior height of 13.0 mm an anterior height of 9.0 mm,
a length of 23.0 mm, and a composite width of 7.0 mm, two cortical
bone pins each having a diameter of 3.0 mm, and a slope of
10.8.degree., having diametrically opposed chamfered edges at
45.degree. and 0.5 mm in depth, a distance from the center point of
the second pin to the posterior end of the graft of 13.5 mm, and a
distance from the center point of the first in to the posterior end
of the graft of 5.5 mm; (8) a posterior height of 13.0 mm an
anterior height of 11.0 mm, a length of 23.0 mm, and a composite
width of 7.0 mm, two cortical bone pins each having a diameter of
3.0 mm, and a slope of 5.4.degree., having diametrically opposed
chamfered edges at 45.degree. and 0.5 mm in depth, a distance from
the center point of the second pin to the posterior end of the
graft of 13.5 mm, and a distance from the center point of the first
pin to the posterior end of the graft 5.5 mm; (9) a posterior
height of 11.0 mm an anterior height of 9.0 mm, a length of 23.0
mm, and a composite width of 7.0 mm, two cortical bone pins each
having a diameter of 3.0 mm, and a slope of 5.4.degree., having
diametrically opposed chamfered edges at 45.degree. and 0.5 mm in
depth, a distance from the center point of the second pin to the
posterior end of the graft of 13.5 mm, and a distance from the
center point of the first pin to the posterior end of the graft of
5.5 mm; (10) a posterior height of 7.0 mm an anterior height of 5.0
mm, a length of 21.0 mm, two cortical bone pins, and optionally
having diametrically opposed chamfered edges; (11) a posterior
height of 7.0 mm an anterior height of 5.0 mm, a length of 23.0 mm,
two cortical bone pins and optionally having diametrically opposed
chamfered edges; and (12) a posterior height of 7.0 mm an anterior
height of 5.0 mm, a length of 25.0 mm, two cortical bone pins, and
optionally having diametrically opposed chamfered edges.
[0277] The composite bone grafts having a parallel block shape and
optionally having opposing textured surfaces disposed perpendicular
to the interfaces of the bone portions, and optionally having
diametrically opposed chamfered edges, preferably include: a
combination of two or more bone portions, preferably cortical bone
portions, optionally each having a patterned surface such that an
interlocking fit between adjacent bone portions is provided; and:
(a) at least two cortical bone portions each having a width of from
about 1.5 mm to about 10.0 mm, preferably from about 2.0 mm to
about 7.0 mm, more preferably from about 3.0 mm to about 5.0 mm,
and most preferably having a width of about 4.0 mm to give a
composite width of about 15.0 mm; the parallel block composite bone
graft has a height from about 5.0 mm to about 20.0 mm, preferably
from about 7.0 mm to about 19.0 mm, more preferably from about 8.0
mm to about 17.0 mm, and most preferably from about 9.0 mm to about
16.0 mm; and the parallel block composite bone graft has a length
of from about 15.0 mm to about 35.0 mm, preferably from about 17.0
mm to about 30.0 mm, more preferably from about 20.0 mm to about
27.0 mm, and most preferably a length of from about 21.0 mm to
about 25.0 mm. The preferred mechanical connectors include one or
more, preferably two cortical bone pins having a round
cross-section and having a diameter of from about 1.0 mm to about
6.0 mm, preferably from about 2.0 mm to about 5.0 mm, more
preferably from about 2.5 mm to about 4.5 mm, and most preferably a
pin diameter of from about 3.0 mm to about 4.0 mm, where the
diameter of each cortical bone pin may be the same of different.
The diameter of the two corresponding through-holes is preferably
sufficient to provide an interference or frictional or slidable
connection between the bone portions and the pin, preferably a
interference or frictional connection, and
[0278] (b) two or more cortical bone portions layered to form a
graft unit, and optionally one or more cancellous bone portions
disposed between said cortical bone portions, the graft unit being
connected by one or more mechanical connectors, preferably two
cortical bone pins having a diameter of from about 1.0 mm to about
6.0 mm, preferably from about 2.0 mm to about 5.0 mm, more
preferably from about 2.5 mm to about 4.5 mm, and most preferably a
pin diameter of from about 3.0 mm to about 4.0 mm, where the
diameter of each pin may be the same or different, and having a
composite width of from 4.5 mm to about 30.0 mm, preferably from
about 6.0 mm to about 21.0 mm, more preferably from about 9.0 mm to
about 15.0 mm, and most preferably having a width of about 4.0 mm
to give a composite width of about 12.0 mm to about 15.0 mm, a
posterior and anterior height of from about 5.0 m to about 20.0 mm,
preferably from about 9.0 mm to about 17.0 mm, and a length of from
about 20.0 mm to about 30.0 mm, specific preferred configurations
include the following: following configurations: (1) an anterior
and posterior height of about 9.0 mm, and a length of about 25.0
mm; (2) an anterior and posterior height of about 9.0 mm, and a
length of about 21.0 mm; (3) an anterior and posterior height of
about 11.0 mm, and a length of about 25.0 mm; (4) an anterior and
posterior height of about 11.0 mm, and a length of about 21.0 mm;
(5) an anterior and posterior height of about 13.0 mm, and a length
of about 25.0 mm; (6) an anterior and posterior height of about
11.0 mm, and a length of about 23.0 mm; (7) an anterior and
posterior height of about 13.0 mm, and a length of about 23.0 mm;
(8) an anterior and posterior height of about 15.0 mm, and a length
of about 25.0 mm; and (9) an anterior and posterior height of about
17.0 mm, and a length of about 25.0 mm. The foregoing described
parallel block composite bone graft optionally includes a
cancellous bone portion disposed between the two cortical bone
portions and having the same width or a greater width than the
cortical bone portions.
[0279] Most preferable parallel block composite bone grafts include
the following configurations: (a) two or more cortical bone
portions having a composite width of about 15.0 mm, held together
by two round cortical bone pins having a diameter of about 2.0 mm
to about 4.0 mm, where each pin has the same or a different
diameter, the composite graft having a height of about 16.0 mm and
a length of about 25.0 mm,
[0280] (b) a first cortical portion having a width of about 3.0 mm,
a second cortical bone portion having a width of about 3.0 mm, one
or more central cancellous bone portions having a composite width
of about 9.0 mm disposed there between, forming a graft unit, the
graft unit held together by two round cortical bone pins having a
diameter of about 2.0 mm to about 4.0 mm, where the diameter of
each pin is the same or different, the composite graft having a
height of about 16.0 mm and an overall length of about 25.0 mm, the
parallel block composite bone graft also includes opposing textured
surfaces disposed perpendicular to the interfaces of the bone
portions;
[0281] (c) a first cortical bone portion having a width of about
3.0 mm, a second cortical bone portion having a width of about 3.0
mm, a central cancellous bone portion having a width of about 3.0
mm disposed there between, forming a graft unit, the graft unit
held together by two round cortical bone pins having a diameter of
about 2.0 mm to about 4.0 mm, where the diameter of each bone pin
is the same or different, the composite graft having a height of
about 10.0 mm and a length of about 25.0 mm, the parallel block
composite bone graft also includes opposing textured surfaces
disposed perpendicular to the interfaces of the bone portions;
[0282] (d) a first cortical portion having a width of about 3.0 mm,
a second cortical bone portion having a width of about 3.0 mm, a
central cancellous bone portion having a width of about 3.0 mm
disposed there between, forming a graft unit, the graft unit held
together by two round cortical bone pins having a diameter of about
2.0 mm to about 4.0 mm, where the diameter is the same or
different, the composite graft having a height of about 9.0 mm and
a length of about 21.0 mm,
[0283] (e) a first cortical portion having a width of about 3.0 mm,
a second cortical bone portion having a width of about 3.0 mm, a
central cancellous bone portion having a width of about 5.0 mm
disposed there between, forming a graft unit, the graft unit held
together by two round cortical bone pins having a diameter of about
2.0 mm to about 4.0 mm, Where the diameter of each bone pin is the
same or different, the composite graft having a height of about
11.0 mm and a length of about 21.0 mm, and
[0284] (f) a first cortical portion having a width of about 3.0 mm,
a second cortical bone portion having a width of about 3.0 mm, a
central cancellous bone portion having a width of about 7.0 mm
disposed there between, forming a graft unit, the graft unit held
together by two round cortical bone pins having a diameter of about
2.0 mm to about 4.0 min, where the diameter of each bone pin is the
same or different, the composite graft having a height of about
13.0 mm and a length of about 21.0 mm.
[0285] Most preferable cortical block composite bone grafts include
the following configurations: (a) a plurality of cortical bone
portions each having a width of from about 3.0 mm to about 4.0 mm,
preferably about 3.0 mm and the plurality of cortical bone portions
having a composite width of from about 18.0 to about 22.0 mm,
preferably a composite width of about 20.0 mm, the cortical block
composite has a height of from about 18.0 to about 22.0 mm,
preferably of about 20.0 mm and a length of from about 18.0 to
about 22.0 mm, preferably of about 20.0 mm or 21.0 mm, with the
graft unit held together by two round cortical bone pins having a
diameter of about 2.0 mm to about 4.0 mm, where the diameter of
each pin is the same or different, and (b) the cortical block
composite bone graft of (a) where one or more of the central
cortical bone portions are replaced with one or more cancellous
bone portions having an overall width of from about 3.0 to about
15.0 mm, preferably about 14.0 mm.
[0286] Most preferable cervical wedge grafts (flattened curved
wedge composite bone grafts) for cervical fusion, include the
following configurations: a combination of two or more cortical
bone portions optionally each having a patterned surface such that
an interlocking fit between the bone portions is provided, and: (a)
a first cervical (flattened curved) cortical portion having a width
of from about 2.0 mm to about 8.0 mm; a second cervical cortical
bone portion having a width of from about 2.0 mm to about 8.0 mm;
where the first portion is disposed on the second portion forming a
graft unit, the graft unit is held together by at least two
cortical bone pins having a diameter of from about 2.0 mm to about
4.0 mm, preferably 2.0 mm to about 3.0 mm; where the diameter of
each pin is the same or different, the composite graft having a
width of about 10.0 to about 20.0 mm, preferably about 16.0 mm, a
diameter of about 10.0 mm to about 18.0 mm, preferably about 13.0
mm, and a centrally located hole, preferably from about 2.0 to
about 8.0 mm in diameter, more preferably from about 3.0 to about
5.0 mm in diameter, disposed through the pinned graft unit, between
at least two pins. Each of the top and bottom surfaces of the
cervical fusion graft, from a side view, may be sloped at an angle
of from about 0.degree. to about 15.degree., preferably at an angle
of from about 3.degree. to about 10.degree., and most preferably
one of the top or bottom surfaces sloped at an angle of about
7.degree. with the other surface not sloped, along the top and
bottom faces of the graft from the curved top end to the flattened
bottom end as shown in FIGS. 14 and 15, to form the wedge shape.
The anterior composite width at the flattened end is preferably
from about 6.0 to about 8.0 mm. The top and bottom opposing faces
of the cervical graft may optionally be textured, preferably with a
plurality of pyrimidal protrusions,
[0287] (b) a first cervical (flattened curved) cortical portion
having a width of from about 2.0 mm to about 8.0 mm; a second
cervical cortical bone portion having a width of from about 2.0 mm
to about 8.0 mm; where the first portion is disposed on the second
portion forming a graft unit, the graft unit is held together by at
least two cortical bone pins having a diameter of from about 2.0 mm
to about 4.0 mm, preferably 2.0 mm to about 3.0 mm; where the
diameter of each pin may be the same or different, the composite
graft having a width of about 15.0 to about 25.0 mm, preferably
about 19.0 mm, a diameter of about 12.0 mm to about 20.0 mm,
preferably about 15.0 mm, and a centrally located hole disposed
through the pinned graft unit, between at least two pins. The
cervical fusion graft, from a side view, is preferably sloped at an
angle of from about 3.degree. to about 15.degree., preferably at an
angle of about 7.degree. along the top and bottom faces, or an
angle of 0.degree. along the top surface and an angle of 7.degree.
along the bottom surface, of the graft from the curved end to the
flattened end as shown in FIGS. 14 and 15, to form the wedge shape.
The anterior composite width at the flattened end is preferably
from about 6.0 to about 8.0 mm. The top and bottom opposing faces
of the cervical graft may optionally be textured, preferably with a
plurality of pyrimidal protrusions,
[0288] (c) a first and a second cervical (flattened curved)
cortical bone portion, the first bone portion disposed on the
second bone portion to form a graft unit, the graft unit is held
together by at least two cortical bone pins having a diameter of
from about 2.0 mm to about 4.0 mm, and having the following
preferred configurations: a posterior composite width of from 5.0
mm to 15.0 mm, preferably from about 8.0 mm to 10.0 mm, an anterior
composite width of from about 5.0 mm to about 10.0 mm, preferably
from about 6.0 mm to about 8.0 mm, the composite graft having a
width of from about 12.0 to about 25.0 mm, preferably from about
16.0 mm to about 19.0 mm, a diameter of from about 10.0 mm to about
20.0 mm, preferably from about 13.0 mm to about 15.0 mm, and a
centrally located hole disposed through the pinned graft unit,
between at least two pins. The graft, from a side view, is
preferably sloped at an angle of from about 3.degree. to about
15.degree., preferably at an angle of about 7.degree., or an angle
of 0.degree. along the top surface and an angle of 7.degree. along
the bottom surface, along the top and bottom faces of the graft
from the curved end to the flattened end as shown in FIGS. 14 and
15, to form the wedge shape. The top and bottom opposing faces of
the cervical graft may optionally be textured, preferably with a
plurality of pyrimidal protrusions; and
[0289] (d) two or more bone portions preferably cortical bone
portions, layered to form a graft unit, where the bone portions are
connected by: being configured to interlock with each other where
the interlocking is self-locking or is locked with one or more pins
entirely or partially traversing a dimension of the graft, and/or
at least two cortical bone pins having a diameter of from about 2.0
mm to about 4.0 mm and having the following preferred
configurations: (I) a diameter of about 14.0 mm; a width of about
17.5 mm; a pin diameter of about 2.5 mm; a through-hole having a
diameter of about 6.5 mm, a first width of about 9.0 mm, and a
second width of about 4.0 mm; a distance from the arc to a pin and
from the through-hole to the second width of the graft, of about
2.0 mm; a second width of about 10.0 mm, and the graft having its
sides sloped at an angle of about 25.degree. (see FIG. 44); and
(ii) a diameter of about 12.0 mm; a width of about 14.5 mm; a pin
diameter of about 2.5 mm; a through-hole having a diameter of about
4.0 mm; a distance from the arc to a pin and from the through-hole
to the second width of the graft, and from the pin to the
through-hole, of about 2.0 mm; a second width of about 7.75 mm, and
the graft having its sides sloped at an angle of about 25.degree.
(see FIG. 43).
[0290] Most preferable anterior lumbar oval wedge composite bone
grafts include the following configurations: (a) two or more ovoid
cortical bone portions disposed on each other thereby forming a
graft unit having a composite posterior width of from about 5.0 mm
to about 20.0 mm, preferably from about 1.0 mm to about 15.0 mm, an
anterior composite width of from 5.0 mm to about 20.0 mm,
preferably from about 8.0 mm to about 14.0 mm, a height of from
about 15.0 mm to about 30.0 mm, preferably from about 21.0 mm to
about 28.0 mm, and a length of from about 23.0 mm to about 45.0 mm,
preferably from about 32.0 mm to about 42.0 mm; the graft unit is
held together by at least two cortical bone pins having a diameter
of from about 2.0 mm to about 4.0 mm, where the pins have the same
or a different diameter, to form a pinned graft unit; and
optionally one or more through-holes disposed through the pinned
graft unit. The graft, from a side view, is preferably sloped at an
angle of from about 3.degree. to about 15.degree., preferably at an
angle of about 7.degree., or an angle of 0.degree. along the top
surface and an angle of 7.degree. along the bottom surface, along
the top and bottom faces of the to form the wedge shape. The top
and bottom opposing faces of the cervical graft may optionally be
textured.
[0291] Any one or more of the cortical and/or cancellous bone
portions of the above-described composite bone grafts, may
optionally be demineralized and/or discontinuous, depending upon
the particular clinical application. For example, any one or more
bone portions of any composite graft may include for example, one
or more horizontally disposed channels, vertically disposed
channels or randomly disposed channels, partially or completely
traversing the height and/or width of the graft. One of ordinary
skill in the art to which the present invention pertains can
readily select, make and employ, a particular composite graft,
without undue experimentation.
V. Surgical Implantation and Indications
[0292] The present composite bone graft is useful for implantation
inpatients suffering from defects caused by congenital anomaly,
disease, or trauma, including for example, spine fractures;
deformity, e.g. kyphotic deformities, e.g. posttraumatic kyphosis;
postlaminectomy kyphosis, junctional kyphosis, and Scheuermann's
kyphosis; scoliosis, e.g. neuromuscular scoliosis, adult scoliosis,
paralytic scoliosis, congenital and syndromic scoliosis; and
cervical neck pain. Surgical methods for correcting degenerative
conditions, for example in the lumbar spine, include decompression
(excision of disc material, hypertrophied bone, or ligament along
with fusion, or fusion alone.
[0293] A posterior surgical approach is preferably used. The choice
of approach is dictated by the site of primary pathology and the
physical size of the composite bone graft. Pathology that involves
vertebral bodies is best approached anteriorly through the thorax,
abdomen or flank. Pathology involving posterior elements are best
approached posteriorly for example, through a vertical midline
approach or posterior lateral muscle spinning approach.
[0294] Those of ordinary skill in the art to which the present
invention pertain, including for example an orthopaedic surgeon and
a spinal surgeon, can readily select and employ a particular
composite bone graft, without undue experimentation. Factors to be
considered in such selection and employment include: the type and
size of graft bone, its anatomic site of fusion, and the age of the
patient. An ideal graft, for example for use in lumbar interbody
fusion, should be: osteoinductive, non-immunogenic, provide
immediate mechanical stability, and be appropriately sized and
shaped for the particular application/patient. Indications,
diagnostic criteria, graft selection and surgical technique, are
factors that can be readily selected, optimized and employed by
those of ordinary skill in the art without undue experimentation,
and are discussed in: Master Techniques in Orthopaedic Surgery, The
Spine, edited by Bradford, David S., Lippincott-Raven, ISBN
0-7817-0033-7, Philadelphia, Pa., (1997), hereby incorporated
herein by reference in its entirety. When implanting a cervical
fusion graft, an anterior cervical approach is used.
[0295] The following examples are illustrative only, and do not in
any way limit the scope of the invention.
EXAMPLES
I. Preparation of a Composite Graft
[0296] Donor bone was harvested according to industry accepted
standards from a cadaver donor. The composite bone grafts, sized as
recorded in Table 1, were prepared according to the method
described as follows. Using a bandsaw cortical planks and pin
segments were cut from a cortical shaft. One surface of each
cortical planks was smoothed on a planing table and the planks were
cut to the recorded thickness using a mill. Thereafter, using a
table saw, the cut planks were cut to the recorded width and
length. Cortical pins were then cut using a drill press, from the
pin segments. Using a drill sander, the cortical pins were tapered
sufficient to allow insertion into the reamed graft unit. Next,
using a bandsaw, cancellous wafers were cut from cancellous bone to
the recorded thickness. The wafers were then cut to the recorded
width and length using a table saw. The cortical planks and
cancellous wafer were then assembled into a graft unit in a jig and
were then reamed using a drill press. The anterior through-hole was
disposed through the width of the graft unit at the through-hole's
center point, 7.5 mm along the length of the graft unit, and
centered relative to the width of the graft unit. Using an arbor
press, the cortical pins were pushed into the reamed graft unit to
produce a pinned graft unit. Any excess pin was then cut off using
a bandsaw. Next, using a drill sander, the pinned graft unit was
then shaped to the final recorded width, and if the composite graft
was angled, the pinned graft was then milled to cut angles. The
composite graft was milled to provide grooves of the recorded
height, on the opposing surfaces as shown in the Figures. The
produced composite bone grafts were then cleaned and tested as
follows.
TABLE-US-00001 TABLE 1 Composite Specimen Composite Tooth (mm)
Height (mm) Length Pins (mm) Cancellous* Cortical* number Graft
Type width (mm) Height angle front back (mm) front back width (mm)
width (mm) 1 trapezoid wedge(TA) 9.0 1.2 60.0.degree. 8.0 10.0 21.0
2.5 3.0 3.0 3.0 2 trapezoid wedge(TB) 11.0 1.5 60.0.degree. 10.0
12.0 21.0 3.0 3.0 5.0 3.0 3 trapezoid wedge(TC) 13.0 1.5
60.0.degree. 12.0 14.0 21.0 3.0 3.0 5.0 4.0 4 trapezoid wedge(TD)
13.0 1.5 60.0.degree. 12.0 14.0 21.0 3.0 3.0 5.0 4.0** 5 parallel
block(PA) 7.0 1.2 60.0.degree. 9.0 9.0 21.0 2.5 2.5 3.0 2.0 6
parallel block(PB) 9.0 1.2 60.0.degree. 9.0 9.0 21.0 2.5 2.5 3.0
3.0 7 parallel block(PC) 9.0 1.2 60.0.degree. 11.0 11.0 21.0 3.0
3.0 3.0 3.0 8 parallel block(PD) 9.0 1.2 60.0.degree. 10.0 10.0
21.0 2.5 3.0 3.0 3.0 9 parallel block(PE) 11.0 1.5 60.0.degree.
13.0 13.0 21.0 3.0 3.0 5.0 3.0 10 parallel block(PF) 11.0 1.5
60.0.degree. 12.0 12.0 21.0 3.0 3.0 5.0 3.0 12 parallel block(PG)
13.0 1.5 60.0.degree. 14.0 14.0 21.0 3.0 3.0 5.0 4.0** 11 parallel
block(PH) 11.0 -- -- 9.0 9.0 21.0 3.0 3.0 5.0 3.0 12 parallel
block(PI) 11.0 -- -- 9.0 9.0 21.0 3.0 3.0 3.0 4.0** 13 parallel
block(PJ) 9.0 -- -- 7.0 7.0 21.0 2.5 2.5 3.0 3.0 *+0.500 mm or
-0.250 mm **two (2) cortical planks were used, each ~2.0 mm to give
a composite cortical width of 4.0 mm
II. Biomechanical Strength
[0297] The biomechanical strength of the composite bone grafts
recorded in Table 2 was determined using static compression
testing. All of the tested bone grafts were produced as set forth
in Example 1, and sized as recorded. All of the composite bone
grafts were constructed from two cortical layers sandwiching a
cancellous layer with all of the layers oriented parallel to the
sagittal plane, and secured together with two cortical bone pins.
Tests were performed under a compressive load using an Instron.TM.
4204 test machine. An axial displacement was applied in a ramp
fashion at 2.5 mm/min rate until catastrophic failure of the bone
graft occurred or until the maximum displacement of 3 mm was
reached. Data was collected at a rate of 2 Hz.
[0298] As can be seen from the data set forth in Table 2, all of
the composite grafts exhibited adequate to exceptional
biomechanical strength, as compared to the vertebral body itself
which fails at 10,000 N (2,200 lbs).
TABLE-US-00002 TABLE 2 Load at Displacement Load at Displacement
Stiffness (slope) Specimen Max. Load at Max. Load z-slp, yield at
z-slp, yield (AutYoung) Graft Type number (KN) (Mm) (Mm) (Mm)
(N/mm) PA PA-1 8.464 3.460 6.719 1.706 6708.0 (Donor 1) PA-2 8.923
2.450 8.625 1.957 6544.0 PA-3 8.569 3.020 7.323 1.851 6201.0 PA-4
7.238 3.070 6.727 1.998 4756.0 PA-5 8.395 2.160 8.078 1.873 7321.0
Mean (Donor 1): 8.318 2.832 7.495 1.877 6306 Std. Dev (Donor 1):
.637 .521 .842 .113 957 (Donor 2) PA-6 9.718 3.300 6.636 1.560
5637.0 PA-7 8.118 1.970 8.113 1.956 6379.0 PA-8 11.190 3.150 9.052
2.102 6246.0 PA-9 8.201 2.110 8.193 2.102 6643.0 PA-10 5.992 1.430
5.882 1.248 7973.0 PA-11 7.248 2.500 7.130 2.060 6578.0 PA-12 8.319
2.660 8.228 2.123 6500.0 PA-13 6.325 2.690 5.782 1.624 4518.0 PA-14
7.973 1.770 7.970 1.749 5867.0 PA-15 8.969 2.750 -- -- 5546.0 Mean
(Donor 2): 8.205 2.433 -- -- 6189.0 Std. Dev. (Donor 2): 1.535 .601
-- -- 900.0 (Donor 3) PA-16 7.259 1.540 7.256 1.541 8207.0 (Donor
4) PA-17 9.799 1.710 9.799 1.687 9930.0 PA-18 7.879 1.640 7.876
1.623 7963.0 PA-19 9.590 1.620 9.584 1.603 9794.0 PA-20 9.388 1.670
9.380 1.665 8773.0 PA-21 9.617 1.750 9.617 1.748 10260.0 Mean
(Doner 4): 9.255 1.678 9.251 1.655 9344.0 Std. Dev. (Donor 4) .783
.053 .783 .057 950 PC PC-1 9.165 4.000 7.216 1.811 10230.0 (Donor
5) PC-2 7.664 2.860 7.664 2.853 4291.0 PC-3 8.360 2.810 8.338 2.791
4226.0 PC-4 8.612 .970 8.607 .958 19260.0 Mean (Donor 5): 8.450
2.660 7.956 2.103 9503.0 Std. Dev. (Donor 5): .623 1.254 .633 .900
7090.0 (Donor 6) PC-5 10.45 2.040 10.36 1.540 9482.0 PC-6 10.17
2.140 10.17 2.144 7261.0 PC-7 11.74 2.090 11.73 2.060 10330.0 PC-8
11.77 2.290 11.76 2.290 9123.0 Mean (Donor 6): 11.03 2.140 11.01
2.009 9049.0 Std. Dev. (Donor 6): .84 .108 .86 .326 1295.0 PB PB-1
8.953 1.540 8.604 1.310 10160.0 (Donor 7) PB-2 10.910 1.850 10.910
1.852 10380.0 Mean (Donor 7): 9.931 1.695 9.758 1.581 10270.0 Std.
Dev. (Donor 7): 1.336 .219 1.632 .383 156.0 PE PE-1 11.42 1.810
11.21 1.601 13900.0 (Donor 8)
III. Comparative Biomechanical Strength
[0299] Composite bone grafts were produced as described in Example
A. 11.times.9.times.21 mm grafts: (PH) having two 3.0 mm cortical
layers sandwiching a 5.0 mm cancellous layer, and (PI) having two
4.0 mm cortical layers sandwiching a 3.0 mm cancellous layer; and
9.times.7.times.21 mm grafts (PJ) having two 3.0 mm cortical layers
sandwiching a 3.0 mm cancellous layer, were produced. After
production, the grafts were either fresh frozen or freeze-dried.
Table 3 summarizes the compression test results of fresh frozen
composite grafts after thawing in 9.0% saline solution for 90
minutes and the freeze-dried composite bone grafts after soaking
for 20 min., 60 min., and 7 days in 9.0% saline solution.
[0300] Test results showed that the 20 minute soaked freeze-dried
grafts had the highest strength (Table 3) and stiffness (Table 4)
among all the tested groups. Generally, strength and stiffness of
the fresh-frozen grafts were relatively lower than the freeze-dried
grafts.
[0301] The inventive composite bone graft, both fresh-frozen and
freeze-dried, when compared to commercially available bone graft
products (Os.TM. and Mid America) was significantly stronger. See
Brantigan et al, Compression Strength of Donor Bone for Posterior
Lumbar Interbody Fusion, Spine Vol. 18, No. 9, 1993.
TABLE-US-00003 TABLE 3 Specimen Number Graft Type 1 2 3 4 5 Mean
Std. Dev. Fresh Frozen-one-hour 9.114 9.160 6.942 6.945 9.852 8.403
1.364 (PH-1) Fresh Frozen-one-hour 9.176 8.744 -- -- -- 8.960 0.305
(PH-2) Freeze-dried-20.0 min. 13.970 14.460 -- -- -- 14.220 0.346
(PI-1) Freeze-dried-one-hour 13.99 13.97 -- -- -- 13.98 0.014
(PI-2) Freeze-dried-seven-days 10.300 8.255 -- -- -- 9.277 1.446
(PI-3) Fresh Frozen-one-hour 7.925 7.973 8.958 7.836 9.799 8.498
.985 (PJ-1) Fresh Frozen-one-hour 8.897 9.015 -- -- -- 8.956 .083
(PJ-2) Os .TM. .cndot. 1.098 .934 5.72 2.145 -- 2.474 2.229 Mid
America Tricortical .cndot. .cndot. 2.823 1.699 1.926 2.629 2.464
2.308 0.477 .cndot. Os .TM. bone is a commercial tricortical bone
graft product. .cndot. .cndot. Mid America tricortical is a
commercially available bone graft product produced by Mid
America.
TABLE-US-00004 TABLE 4 Specimen Number Graft Type 1 2 3 4 5 Mean
Std. Dev. Fresh Frozen-one-hour 7053.0 6176.0 5878.0 5434.0 7528.0
6413.8 1103.4 (PJ-1) (9 .times. 7, 3-3-3) Fresh Frozen-one-hour
7303.0 6112.0 -- -- -- 6707.5 842.2 (PJ-2) (9 .times. 7, 3-3-3)
Fresh Frozen-one-hour 10980.0 13900.0 -- -- -- 12440.0 2064.8
(PH-1) (11 .times. 9, 3-5-3) Fresh Frozen-one-hour 4938.0 11340.0
11060.0 12180.0 9125.0 9728.0 2902.3 (PH-2) (11 .times. 9, 3-5-3)
Freeze-dried-20.0 min. 27760.0 28420.0 -- -- -- 28090.0 466.7
(PI-1) (11 .times. 9, 4-3-4) Freeze-dried-one-hour 21940.0 22890.0
-- -- -- 22415.0 671.8 (PI-2) (11 .times. 9, 4-3-4)
Freeze-dried-seven-days 14590.0 18130.0 -- -- -- 16360.0 2503.2
(PI-3) (11 .times. 9, 4-3-4)
IV. Preparation of a Cervical Wedge Composite Graft
[0302] Donor bone was harvested according to industry accepted
standards from a cadaver donor. The composite bone grafts, sized as
recorded in Table 5, were prepared according to the method
described as follows. Using a bandsaw cortical planks and pin
segments were cut from a cortical shaft. One surface of each
cortical planks was smoothed on a planing table and the planks were
cut to the required thickness using a mill. Thereafter, using a
table saw, the cut planks were cut to the required width and
length. Cortical pins were then cut using a drill press, from the
pin segments. Using a drill sander, the cortical pins were tapered
sufficient to allow insertion into the reamed graft unit. Next, the
cortical planks were assembled into a graft unit in a jig and were
then reamed using a drill press. Using an arbor press, the cortical
pins were pushed into the reamed graft unit to produce a pinned
unit. At this point, the pinned unit was optionally sloped at it's
top and/or bottom surface, for example at its bottom surface, at
7.degree. using a radial saw. A circular shape was then cut through
the pinned and optionally sloped unit using a trephine or Cloward
cutter of appropriate size. Thereafter, using a radial saw or a
band saw, the sides and bottom of the graft were shaped, and a
centrally located hole was drilled through the pinned unit. Any
excess pin was then cut off using a bandsaw. Lastly, the pinned
graft unit was smoothed. If textured, the composite graft was
milled to provide grooves on the opposing surfaces as shown in FIG.
35.
TABLE-US-00005 TABLE 5 Composite Specimen Width(mm) Diameter Width
number Graft Type Front back (Mm) (Mm) 1. Cervical Wedge (CA) 6.0
10.0 13.0 16.0 2. Cervical Wedge (CB) 7.0 11.0 13.0 16.0 3.
Cervical Wedge (CC) 8.0 12.0 13.0 16.0 4. Cervical Wedge (CD) 6.0
10.0 15.0 19.0 5. Cervical Wedge (CE) 7.0 11.0 15.0 19.0 6.
Cervical Wedge (CF) 8.0 12.0 15.0 19.0 7. Cervical Wedge (CG) 6.0
6.0 13.0 16.0 8. Cervical Wedge (CH) 8.0 8.0 13.0 16.0 9. Cervical
Wedge (CI) 6.0 6.0 15.0 19.0 10. Cervical Wedge (CJ) 7.0 7.0 13.0
16.0 11. Cervical Wedge (CK) 7.0 7.0 15.0 19.0
[0303] It is to be understood, however, that the scope of the
present invention is not to be limited to the specific embodiments
described above. The invention may be practiced other than as
particularly described and still be within the scope of the
accompanying claims.
* * * * *