U.S. patent application number 11/053454 was filed with the patent office on 2005-11-03 for plasticized bone and soft tissue grafts and methods of making and using same.
Invention is credited to Anderson, Billy G., O'Leary, Robert K., Wolfinbarger, Lloyd JR..
Application Number | 20050246035 11/053454 |
Document ID | / |
Family ID | 22316720 |
Filed Date | 2005-11-03 |
United States Patent
Application |
20050246035 |
Kind Code |
A1 |
Wolfinbarger, Lloyd JR. ; et
al. |
November 3, 2005 |
Plasticized bone and soft tissue grafts and methods of making and
using same
Abstract
The present invention provides a plasticized dehydrated or
freeze-dried bone and/or soft tissue product that does not require
special conditions of storage, for example refrigeration or
freezing, exhibits materials properties that approximate those
properties present in normal hydrated tissue, is not brittle, does
not necessitate rehydration prior to clinical implantation and is
not a potential source for disease transmission. The invention
replaces water in the molecular structure of the bone or soft
tissue matrix with one or more plasticizers allowing for
dehydration of the tissue, yet not resulting in an increase in
brittleness of the plasticized product, and resulting in
compressive and/or tensile properties similar to those of normal
hydrated bone. Replacement of the chemical plasticizers by water
prior to implantation is not required and thus, the dehydrated bone
or soft tissue plasticized product can be placed directly into an
implant site without significant preparation in the operating
room.
Inventors: |
Wolfinbarger, Lloyd JR.;
(Norfolk, VA) ; O'Leary, Robert K.; (Deltaville,
VA) ; Anderson, Billy G.; (Virginia Beach,
VA) |
Correspondence
Address: |
W. Jackson Matney, Jr.
Jenkens & Gilchrist
1445 Ross Avenue, Suite 3200
Dallas
TX
75202
US
|
Family ID: |
22316720 |
Appl. No.: |
11/053454 |
Filed: |
February 9, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11053454 |
Feb 9, 2005 |
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09940545 |
Aug 29, 2001 |
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09940545 |
Aug 29, 2001 |
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09107459 |
Jun 30, 1998 |
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6293970 |
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Current U.S.
Class: |
623/23.61 ;
623/901 |
Current CPC
Class: |
A61F 2/4644 20130101;
A61F 2002/4649 20130101; A61L 27/502 20130101; A61L 27/362
20130101; A61F 2002/4646 20130101; A61L 27/3683 20130101; A61F
2002/2839 20130101; A61L 27/365 20130101; A61L 27/3608 20130101;
A61F 2002/30535 20130101; A61F 2002/2825 20130101; A61F 2002/2835
20130101; A61L 2430/02 20130101; A61F 2/02 20130101; A61F 2250/0058
20130101 |
Class at
Publication: |
623/023.61 ;
623/901 |
International
Class: |
A61F 002/28 |
Claims
1. A plasticized bone graft, comprising: a cleaned bone graft
comprising one or more plasticizers.
2. A plasticized bone graft suitable for transplantation into a
human, comprising: a bone graft having an internal matrix
essentially free from bone marrow elements; and one or more
plasticizers contained in said internal matrix.
3. A plasticized bone graft, comprising: a cleaned bone graft; and
one or more plasticizers, wherein said cleaned bone graft is
impregnated with said one or more plasticizers.
4. The bone graft of any one of claims 1, 2, or 3, wherein said
bone graft is suitable for direct transplant into a human without
rehydration.
5. The bone graft of any one of claims 1, 2, or 3, wherein said
bone graft is a non-demineralized bone graft.
6. The bone graft of any one of claims 1, 2, or 3, wherein said
bone graft is a load-bearing bone graft.
7. The bone graft of any one of claims 1, 2, or 3, wherein said
bone graft is a non load-bearing bone graft.
8. A method for producing a plasticized bone graft suitable for
transplantation into a human, comprising: impregnating a cleaned
bone graft with one or more plasticizers to produce a plasticized
bone graft.
9. The method of claim 8, said step of impregnating, comprising:
incubating said cleaned bone graft with a plasticizer composition
comprising one or more plasticizers and one or more biocompatible
solvents.
10. The method of claim 9, wherein said one or more biocompatible
solvents comprise one or more alcohols.
11. The method of claim 9, wherein incubating comprises soaking
said cleaned bone graft in said plasticizer composition.
12. The method of claim 11, wherein said soaking is carried out
under negative pressure.
13. The method of claim 8, wherein said cleaned bone graft is
essentially free from bone marrow elements.
14. The method of claim 10, wherein said one or more plasticizers
are present in said plasticizer composition in a weight ratio of
from 30 to 90 wt %, and said one or more alcohols are present in
said plasticizer composition in a weight ratio of from 10 to 70 wt
%.
15. The method of claim 14, wherein said plasticizer is glycerol
and said alcohol is isopropyl alcohol.
16. The method of claim 15, wherein said glycerol is present at 30
wt % and said isopropyl alcohol is present at 70 wt %.
17. A plasticized soft tissue graft suitable for transplantation
into a human, comprising: a cleaned soft tissue graft having an
internal matrix; and one or more plasticizers contained in said
internal matrix.
18. A plasticized soft tissue graft, comprising: a cleaned, soft
tissue graft; and one or more plasticizers, wherein said cleaned
soft tissue graft is impregnated with said one or more
plasticizers.
19. A plasticized soft tissue graft, comprising: a cleaned, soft
tissue graft comprising one or more plasticizers.
20. The soft tissue graft of any one of claims 17, 18, or 19,
wherein said soft tissue graft is suitable for direct transplant
into a human without rehydration.
21. The soft tissue graft of any one of claims 17, 18, or 19,
wherein said soft tissue graft is a load-bearing soft tissue
graft.
22. The soft tissue graft of any one of claims 17, 18, or 19,
wherein said soft tissue graft is a non load-bearing soft tissue
graft.
23. The soft tissue graft of any one of claims 17, 18, or 19,
wherein said soft tissue graft is selected from the group
consisting of: dura, pericardium, fascia lata, tendons and
ligaments.
24. A method for producing a plasticized soft tissue graft suitable
for transplantation into a human, comprising: impregnating a
cleaned, soft tissue graft with one or more plasticizers to produce
a plasticized soft tissue graft.
25. The method of claim 24, said step of impregnating, comprising:
incubating said cleaned, soft tissue graft with a plasticizer
composition comprising one or more plasticizers and one or more
biocompatible solvents.
26. The method of claim 25, wherein incubating comprises soaking
said cleaned, soft tissue graft in said plasticizer
composition.
27. The method of claim 25, wherein said soaking is carried out
under negative pressure.
28. The method of claim 26, wherein said one or more biocompatible
solvents comprise one or more alcohols.
29. The method of claim 28, wherein said one or more plasticizers
are present in said plasticizer composition in a weight ratio of
from 30 to 90 wt %, and said one or more alcohols are present in
said plasticizer composition in a weight ratio of from 10 to 70 wt
%.
30. The method of claim 28, wherein said plasticizer is glycerol
and said alcohol is isopropyl alcohol.
31. The method of claim 30, wherein said glycerol is present at 30
wt % and said isopropyl alcohol is present at 70 wt %.
32. A plasticized bone graft, comprising: a cleaned,
non-demineralized bone graft comprising one or more
plasticizers.
33. The plasticized bone graft of claim 32, wherein the
non-demineralized bone graft is non load-bearing.
34. A plasticized load-bearing, bone graft, comprising: a cleaned,
load-bearing bone graft comprising one or more plasticizers.
35. A plasticized load-bearing soft tissue graft, comprising: a
cleaned, load-bearing soft tissue graft comprising one or more
plasticizers.
36. A plasticized bone graft, comprising: a non load-bearing bone
graft comprising one or more plasticizers.
37. A plasticized bone graft, comprising: a non-load-bearing bone
graft; and one or more plasticizers, wherein said bone graft is
impregnated with said one or more plasticizers.
38. A method for producing a plasticized bone graft suitable for
transplantation into a human, comprising: impregnating a non
load-bearing bone graft with one or more plasticizers to produce a
plasticized bone graft.
39. A plasticized soft tissue graft suitable for transplantation
into a human, comprising: a soft tissue graft having an internal
matrix; and one or more plasticizers contained in said internal
matrix.
40. A plasticized soft tissue graft, comprising: a cleaned soft
tissue graft; and one or more plasticizers, wherein said cleaned
soft tissue graft is impregnated with said one or more
plasticizers.
41. A plasticized soft tissue graft, comprising: a soft tissue
graft comprising one or more plasticizers.
42. The plasticized soft tissue graft of any one of claims 39, 40,
or 41, wherein said soft tissue graft is a non load-bearing soft
tissue graft.
43. The plasticized soft tissue graft of any one of claims 39, 40,
or 41, wherein said soft tissue graft is a load-bearing soft tissue
graft.
Description
[0001] This is a continuation application of U.S. patent
application Ser. No. 09/940,545, filed on Aug. 29, 2001, now U.S.
Pat. No. ______, which is a divisional application of U.S. patent
application Ser. No. 09/107,459 filed on Jun. 30, 1998, now U.S.
Pat. No. 6,293,970.
FIELD OF THE INVENTION
[0002] The present invention provides a plasticized dehydrated bone
and/or soft tissue product that does not require special conditions
of storage, for example refrigeration or freezing, exhibits
materials properties that approximate those properties present in
normal hydrated tissue, is not brittle and does not necessitate
rehydration prior to clinical implantation. The invention replaces
water in the molecular structure of the bone or soft tissue matrix
with one or more plasticizers allowing for dehydration of the
tissue, yet not resulting in an increase in brittleness of the
plasticized product, and resulting in compressive and/or tensile
properties similar to those of normal hydrated bone. Replacement of
the chemical plasticizers by water prior to implantation is not
required and thus, the dehydrated bone or soft tissue plasticized
product can be placed directly into an implant site without
significant preparation in the operating room. The present
plasticized graft does not need rehydration, possesses adequate
materials properties, and is not a potential source for disease
transmission.
BACKGROUND OF THE INVENTION
[0003] Bone tissue is a homogeneous material comprised of osteoid
and minerals. The osteoid is a viscous gel-like material comprised
primarily of type I collagen (approximately 90%), proteoglycans,
and various sulfated and non-sulfated mucopolysaccharides. The
mineral component consists primarily of a crystalline form of
calcium phosphate, hydroxy apatite, with amounts of calcium
carbonate, tricalcium phosphate, and smaller amounts of other forms
of mineral salts. This bone tissue is laid down around cells called
osteocytes and these cells are found in small interconnected
channels (lacunae) which are interconnected through a series of
channels comprising the Haversian canal system. At the level of the
microscope, it is possible to observe that bone tissue is organized
into osteons of compact bone made of concentric, perivascular
layers of highly coaligned mineralized collagen fiber bundles. The
predominant orientation within a single layer varies with respect
to the vascular axis and various combinations of orientation in
successive lamellae result in variable overall collagen orientation
within each osteon. Differences in overall collagen orientation are
directly reflected in differing mechanical behavior of single
osteons. Transversely oriented collagen results in better
resistance to compressive loading along the axis, whereas
predominant longitudinal orientation results in better resistance
to tensile stress. The predominant orientation of collagen within a
cross-section of long bone is not random, but matches the expected
distribution of mechanical stress across the section, and its
rotational shift along the whole shaft. More transverse collagen is
deposited at sites of compressive loading, and more longitudinal
collagen is deposited at sites of tensile stress. These structural
oriented bone tissues in a load bearing bone are presumed to be
laid down by the osteocytes present in the bone and bone remodeling
mediates mechanical adaptation in compact bone.
[0004] A bone is typically comprised of bone tissue in the form of
cortical and trabecular bone. Cortical bone is frequently referred
to as compact bone and is the major load-bearing part of a bone.
Trabecular bone is present in what is typically referred to as
cancellous bone where it appears as a densely interconnected
structure of "spongy" bone. Spongy bone in a typical bone contains
the hemotopoietic cellular elements which is called bone marrow.
Trabecular bone can be described as forming a cross-bracing lattice
between cortical bone in a bone. It is important to emphasize a
need to differentiate between "a bone" and "bone" (as a tissue). A
bone is comprised of bone tissue present as cortical and cancellous
(spongy) bone.
[0005] The mineralized osteoid typical of bone tissue is hydrated
along the organic molecular structure and is an essential element
of the mineral structure. Hydrating molecules of water form complex
molecular associations with these organic and non-organic elements
of bone tissue and can be described as being tightly bound, loosely
bound, and free. Free water and loosely bound water can frequently
be removed from bone tissue with only minor changes in the overall
mechanical characteristics of the bone tissue. Tightly bound water
can be removed only under extreme conditions and results in
significant changes in the physical and mechanical properties of
bone tissue. In fresh bone, water serves a solvating function in
bone tissue allowing proper orientation and molecular spacing of
the collagen fibrils which maintain structural alignment of the
mineral phase in association with the organic phase.
[0006] Bone tissue in the form of bone grafts for implantation into
a patient, is typically preserved and provided in a dehydrated
state. Dehydration of bone tissue through drying, whether by air
drying or sublimation as in freeze-drying, results in alteration of
the molecular structure of the bone tissue and as a result of the
reorientation of the collagen fibrils and the crystalline mineral
phase, stress accumulates in the bone tissue. This stress can be
relieved by rehydration or by the occurrence of small or large
dislocations of structure. Small dislocations are designated micro
fractures and are not usually visible to the naked eye. Large
dislocations are designated fractures and are usually visible to
the naked eye.
[0007] In a long bone, for example a femur, tibia, fibula, or
humerus, the shaft separates the proximal and distal ends of the
long bone. The shaft serves to focus loads applied to the whole
bone into a smaller diameter than found at the proximal and distal
ends of the long bone and the shaft of a long bone is typically of
a cylindrical shape and is comprised of compact (cortical) bone.
Loads applied along the axis of the shaft require that the cortical
bone maintain a constant circumference, i.e. the tendency to
failure would distort the bone tissue perpendicular to the axis of
load application. Thus, the orientation of the collagen fibers
should be such that tensile stress is resisted along the axis of
loading and compressive stress is resisted perpendicular to
loading. Drying of shaft portions of long bones results in
reorientation of collagen fibers and the mineral phase such that
changes in the circumferential orientation create stress within the
bone matrix which can be relieved only by rehydration or occurrence
of a fracture which allows a reorientation approximating the
original orientation. In dehydrated cortical ring grafts cut from
shafts of long bones, this stress release can present as a fracture
along the long axis of the bone shaft leaving a circumference which
approximates the circumference of the cortical ring graft prior to
drying. By rehydrating bone grafts prior to implantation, the
potential for fracture formation which can compromise the function
of the bone product can be reduced, but not eliminated. Fractures
as discussed above can occur in dehydrated bone prior to
rehydration and result in a graft having compromised biomechanical
properties, which in turn can result in graft failure when
implanted in a patient.
[0008] Load-bearing soft tissue grafts such as ligaments, tendons,
and fascia lata are frequently provided in a freeze-dried state.
Such grafts must be rehydrated prior to clinical implantation. Such
soft tissue grafts typically contain collagen, elastin, and
assorted proteoglycans and mucopolysaccharides. The collagens and
elastins are the load-bearing component(s) of these soft tissue
grafts and the assorted proteoglycans and polysaccharides serve to
bind the fibrillar collagens into a matrix-like structure. The
structural organization of fascia lata is similar to dura mater in
being somewhat isotropic in load-bearing properties (Wolfinbarger,
L, Zhang, Y, Adam, BLT, Homsi, D, Gates, K, and Sutherland, V,
1994, "Biomechanical aspects on rehydrated freeze-dried human
allograft dura mater tissues, J. Applied Biomaterials, 5:265-270)
whereas tendons (for example the Achilles tendon) or ligaments (for
example the Anterior cruciate ligament) are typically anisotropic
in load-bearing properties. In these types of load-bearing soft
tissue grafts, the tensile properties of the tissues depend on the
flexibility of the collagenous structures to stretch under load and
return to their original dimensions upon removal of the load.
[0009] A wide variety of bone and soft tissue products are used in
veterinary, medical, orthopaedic, dental, and cosmetic surgery
applications. These bone and soft tissue products can be used in
load-bearing and non-load bearing applications and the bone and
soft tissue products can be supplied under a variety of forms. Bone
products are provided as fresh-frozen, freeze-dried, rehydrated
freeze-dried, air-dried, organic solvent preserved, or provided
preserved by other similar types of preservation methods. Each
method of preservation of bone products possesses selected
advantages and disadvantages and thus the method of preservation is
generally modified to select for specific needs of a given bone
graft. Soft tissue products are typically provided as fresh-frozen
or freeze-dried and each method of preservation of soft tissue
products possess selected advantages and disadvantages and thus the
method of preservation is generally modified to select for specific
needs of a given soft tissue product.
[0010] Bone and soft tissue products preserved and stored by
methods involving freeze-drying (removal of water by sublimation)
yield a bone or soft tissue product which is significantly more
brittle than normal bone and has a tendency to fracture into
numerous small pieces, which ultimately can result in graft
failure. Specifically, freeze-drying causes grafts to be brittle
and typically causes shrinkage where the shrinkage is often not
uniform, thereby causing graft failure; solvent preservation using
for example, acetone or alcohol, can cause irreversible
denaturation of proteins, and solubilization of solvent soluble
components, including for example, lipids. These alterations in
materials properties of the bone and soft tissue products
necessitates a rehydration step in preparation of the bone and soft
tissue product for implantation. However, rehydration does not
solve the problem, grafts can fracture prior to rehydration,
thereby making rehydration futile, and if there are micro fractures
prior to rehydration they remain after rehydration. These grafts
are more likely to fail regardless of whether they are rehydrated.
Even after rehydration the materials properties do not approximate
the materials properties of normal bone.
[0011] Bone and soft tissue products are generally separated into
load bearing and non-load bearing products. Examples of non-load
bearing bone products are ground demineralized bone which are used
for inducing new bone formation in a particular implant site.
Load-bearing bone products are rarely demineralized and are used at
implant sites where the bone graft will be expected to withstand
some level of physical load(s). It is therefore important that load
bearing bone products not fail during normal movement(s) of the
implant recipient and that the bone product not stimulate a
pronounced physiological response. The majority of bone products
are provided in either the fresh-frozen or freeze-dried format. The
fresh-frozen format is undesirable because it includes donor
derived bone marrow and is thus immunogenic and a source of disease
transmission. The freeze-dried format is less of a problem than
fresh-frozen grafts in the potential for disease transmission,
however a freeze-dried bone graft is significantly more brittle
than normal bone, more brittle than fresh frozen bone, and must be
rehydrated prior to clinical usage. In that clinicians typically do
not have time to adequately rehydrate bone graft products in the
operating room, it is advantageous to provide a dehydrated or
freeze-dried bone product which does not need rehydration,
possesses adequate materials properties, and is not a potential
source for disease transmission.
SUMMARY OF THE INVENTION
[0012] It is an objective of the present invention to provide
implantable, non-demineralized, load-bearing bone products which
are mechanically stabilized in a dehydrated state by use of
biocompatible plasticizers.
[0013] It is a further objective of the present invention to
provide implantable, load-bearing, soft tissue products which are
mechanically stabilized in a dehydrated state by use of
biocompatible plasticizers.
[0014] It is also an objective of the present invention to provide
implantable, load-bearing, bone products which do not require
rehydration.
[0015] It is yet a further objective of the present invention to
provide implantable, load-bearing, soft tissue products which do
not require rehydration.
[0016] It is an objective of the present invention to provide
methods of plasticizing load-bearing bone and soft tissue
products.
[0017] It is a further objective of the present invention to
provide plasticized bone and soft tissue products which are
resistant to proliferation of microorganisms.
[0018] It is yet a further objective of the present invention to
provide bone and soft tissue products which can be stored at room
temperature using conventional packaging.
[0019] It is a further objective of the present invention to
provide plasticized bone and soft tissue products where the
plasticizer can be readily removed prior to implantation.
[0020] It is a further objective of the present invention to use
plasticizers to plasticize bone and soft tissue products which are
not toxic to a recipient of the plasticized bone or soft tissue
graft.
[0021] It is yet a further objective of the present invention to
provide implantable load-bearing bone and soft tissue products
which are similar in physical, chemical, and biological properties
as compared to normal tissue (fresh bone or fresh soft tissues) yet
lack the inherent disadvantages (including for example, potential
disease transmission, increased immunogenicity, and a tissue (e.g.
bone marrow) which can yield toxic degradation products and/or
retard graft incorporation) of fresh-frozen, dehydrated, and
freeze-dried bone and/or soft tissue products.
[0022] It is a further objective of the present invention to
provide a plasticized bone graft suitable for transplantation into
a human, including a non-demineralized bone graft having an
internal matrix essentially free from bone marrow elements; and one
or more plasticizers contained in the internal matrix.
[0023] It is an object of the present invention to provide a
plasticized bone graft, including a cleaned, non-demineralized,
bone graft; and one or more plasticizers, where the cleaned
non-demineralized bone graft is impregnated with the one or more
plasticizers.
[0024] It is yet a further objective of the present invention to
provide a plasticized bone graft, including a cleaned,
non-demineralized, bone graft including one or more
plasticizers.
[0025] It is a further objective of the present invention to
provide a method for producing a plasticized bone graft suitable
for transplantation into a human, by impregnating a cleaned,
non-demineralized, bone graft with one or more plasticizers to
produce a plasticized bone graft.
[0026] Plasticity of soft tissues depends primarily on the waters
of hydration present in the matrix structure, where water movement
under a load is restricted by the viscous nature of the
proteoglycan/polysacchari- de component, and bound waters of
hydration in the collagen component affect the flexibility of the
tensile component of the tissue(s). The present invention deals
with the plasticization of these load bearing tissue constructs
where the water removed is replaced with one or more plasticizers
including for example, glycerol (glycerin USP) (liquid
substitution) such that the graft does not need to be rehydrated or
washed to remove the plasticizer prior to clinical
implantation.
[0027] The present invention provides a dehydrated or freeze-dried
plasticized bone or soft tissue product, preferably containing less
than 5% residual moisture, which product requires no or minimal
processing just prior to clinical implantation. The present
invention solves prior art problems of grafts having insufficient
materials properties, graft brittleness, and the necessity for
rehydration prior to clinical implantation, by providing a
plasticized dehydrated bone and/or soft tissue product that
exhibits materials properties that approximate those properties
present in normal hydrated tissue, is not brittle and does not
necessitate rehydration prior to implantation.
DETAILED DESCRIPTION
[0028] I. Definitions:
[0029] The below definitions serve to provide a clear and
consistent understanding of the specification and claims, including
the scope to be given such terms.
[0030] Alcohol. By the term "alcohol" is intended for the purposes
of the present invention, one of a series of organic chemical
compounds in which a hydrogen attached to carbon is replaced by a
hydroxyl. Suitable alcohols useful in the plasticizer composition
of the present invention preferably include C.sub.1-C.sub.10
alcohols, and more preferably ethanol and isopropyl alcohol.
[0031] Allowash.TM. Solution. By the term "Allowash.TM. Solution"
is intended those detergent compositions disclosed in co-pending
U.S. patent application Ser. No. 08/620,856 incorporated herein by
reference. Examples of suitable Allowash compositions include: a
cleaning composition containing essentially about 0.06 wt %
polyoxyethylene-4-lauryl ether, about 0.02 wt % poly (ethylene
glycol)-p-nonyl-phenyl-ether; about 0.02 wt %
octyphenol-ethyleneoxide and endotoxin free deionized/distilled
water.
[0032] Biocompatible. By the term "biocompatible" is intended for
the purposes of the present invention, any material which does not
provoke an adverse response in a patient. For example, a suitable
biocompatible material when introduced into a patient does not
itself provoke a significant immune response, and is not toxic to
the patient.
[0033] Biomechanical strength. By the term "biomechanical strength"
is intended for the purposes of the present invention, those
properties exhibited by a tissue graft including loading strength,
compressive strength, and tensile strength.
[0034] Bone graft. By the term "bone graft" is intended for the
purposes of the present invention, any bone or piece thereof
obtained from a donor for example a human or animal and/or cadaver
donor, including for example any essentially intact bone graft
including for example the femur, tibia, ilia, humorous, radius,
ulna, ribs, whole vertebrae, mandibula and/or any bone which can be
retrieved from a donor with minimal cutting of that bone for
example, one half of an ulna, a femur cut in half to yield a
proximal half and a distal half, femoral head, acetabula, distal
femur, femur shaft, hemi-pelvi, humerus shaft, proximal femur,
proximal femur with head, proximal humeri, proximal tibia, proximal
tibia/plateaus, talus, tibia shaft, humeral head, ribs, and/or at
least a substantial portion of a whole bone, i.e. at least
one-quarter of a whole bone; and/or any cut bone grafts including
for example an iliac crest wedge, a Cloward dowel, a cancellous
cube, a fibular strut, cancellous block, a crock dowel, femoral
condyles, femoral ring, femur segment, fibula segment, fibular
wedge, tibia wafer, ilium strip, Midas Rex dowel, tibia segment,
and radius/ulna wedge.
[0035] Bone marrow elements. By the term "bone marrow elements" is
intended for the purposes of the present invention, the highly
cellular hemotopoietic 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.
[0036] Cleaned bone graft. By the term "cleaned bone graft" is
intended for the purposes of the present invention, a bone graft
that has been processed using means know in the art, to remove bone
marrow elements.
[0037] Dehydrated bone or soft tissue. By the term "dehydrated bone
or soft tissue" is intended bone tissue or soft tissue which is
preserved by dehydration, such drying methods including for
example, freeze-drying, and/or sublimation and/or air drying and/or
liquid substitution.
[0038] Essentially free from. By the term "essentially free from"
is intended for the purposes of the present invention, a bone graft
where the material removed (i.e., bone marrow elements) from the
bone graft is not detectable using detection means known in the art
at the time of filing of this application.
[0039] Incubating. By the term "incubating" is intended for the
purposes of the present invention, processing a bone graft in for
example a plasticizer composition by soaking the graft in the
composition, shaking the graft with the composition, subjecting the
graft to flow of the composition where the flow is induced by
negative or positive pressure, subjecting the graft and/or the
composition to negative or positive pressure, or soaking the bone
graft in a plasticizer composition in a negative pressure
environment.
[0040] Impregnating. By the term "impregnating" is intended for the
purposes of the present invention, any processing conditions which
result in filling the internal matrix of a bone graft with a
plasticizer composition.
[0041] Internal matrix. By the term "internal matrix" is intended
for the purposes of the present invention, the spongy epiphysis of
bones, the intercellular substance of bone tissue including
collagen fibers and inorganic bone salts; or in soft tissue, the
intercellular substance of such soft tissue including for example
ligaments and tendons, including collagen and elastin fibers and
base matrix substances.
[0042] Load-bearing. By the term "load-bearing" is intended for the
purposes of the present invention a non-demineralized bone product
or soft tissue product for implantation in a patient at a site
where the bone graft or soft tissue graft will be expected to
withstand some level of physical load(s).
[0043] Materials properties. By the term "materials properties" is
intended for the purposes of the present invention, those
properties present in normal fresh bone which include for example,
loading strength, compressive strength, tensile strength, and
deformability.
[0044] Negative pressure. By the term "negative pressure" is
intended for the purposes of the present invention, a pressure
below atmospheric pressure, i.e. below 1 atm.
[0045] Normal bone or soft tissue. By the term "normal bone or soft
tissue" is intended for the purposes of the present invention,
fresh hydrated autogenous and/or fresh-frozen hydrated allograft
tissue including for example, bone, fascia, ligaments, and
tendons.
[0046] Permeation enhancer. By the term "permeation enhancer" is
intended for the purposes of the present invention, any agent
including for example, isopropyl alcohol, that facilitates
penetration of the one or more plasticizers or plasticizer
composition into the bone or soft tissue. In the case of isopropyl
alcohol, permeation is enhanced due to the reduced surface tension
of the alcoholic solution.
[0047] Plasticization. By the term "plasticization" is intended for
the purposes of the present invention, replacing free and loosely
bound waters of hydration in a tissue(s) with one or more
plasticizers without altering the orientation of the collagen
fibers and associated mineral phase.
[0048] Plasticizer. By the term "plasticizer" is intended for the
purposes of the present invention, any biocompatible compounds
which are soluble in water and can easily displace/replace water at
the molecular level and preferably have a low molecular weight such
that the plasticizer fits into the spaces available to water within
the hydrated molecular structure of the bone or soft tissue. Such
plasticizers are preferably not toxic to the cellular elements of
tissue into which the graft is to be placed, or alternatively, the
plasticizer is easily removed from the graft product prior to
implantation. Suitable plasticizers are preferably compatible with
and preferably readily associates with the molecular elements of
the bone tissue and/or soft tissue. Suitable plasticizers include
for example: glycerol (glycerin USP), adonitol, sorbitol, ribitol,
galactitol, D-galactose, 1,3-dihydroxypropanol, ethylene glycol,
triethylene glycol, propylene glycol, glucose, sucrose, mannitol,
xylitol, meso-erythritol, adipic acid, proline, hydroxyproline or
similar water-soluble small molecular weight solutes which can be
expected to replace water in the base matrix structure of bone
tissue and/or soft tissue and provide the hydrating functions of
water in that tissue. Suitable solvents include for example: water,
alcohols, including for example ethanol and isopropyl alcohol.
[0049] Plasticizer composition. By the term "plasticizer
composition" is intended for the purposes of the present invention,
any composition which includes one or more plasticizers and one or
more biocompatible solvents. Suitable solvents include for example:
water, and alcohols, including for example C.sub.1-C.sub.10
alcohols, and more preferably ethanol and isopropyl alcohol.
[0050] Positive pressure. By the term "positive pressure" is
intended for the purposes of the present invention, a pressure
above atmospheric pressure, i.e. above 1 atm.
[0051] Rehydration. By the term "rehydration" is intended for the
purposes of the present invention, hydrating a dehydrated
plasticized tissue graft or a dehydrated non-plasticized tissue
graft, with water, for example, prior to implantation into a
patient. In the case of a plasticized graft, the plasticizer may
optionally be not replaced by water or may optionally be partially
or fully replaced by water.
[0052] Soft tissue grafts. By the term "soft tissue grafts" is
intended for the purposes of the present invention, load-bearing
and non-load-bearing soft tissue products. Non load-bearing grafts
include cadaveric skin. Load-bearing soft tissue grafts include for
example: pericardium, dura mater, fascia lata, and a variety of
ligaments and tendons. Soft tissue grafts are composed of an
internal matrix which includes collagen, elastin and high molecular
weight solutes where during cleaning cellular elements and small
molecular weight solutes are removed.
[0053] II. Plasticizers
[0054] Plasticization of load-bearing bone or soft tissue grafts
represents a method of replacing free and loosely bound waters of
hydration in the tissue(s) with a plasticizer composition
containing one or more plasticizers, without altering the
orientation of the collagen fibers and associated mineral phase.
Suitable plasticizers include compounds which are soluble in water
and can easily displace/replace water at the molecular level.
Suitable plasticizers preferably have a low molecular weight such
that the plasticizer fits into the spaces available to water within
the hydrated molecular structure of the bone or soft tissue. Such
plasticizers are not toxic to the cellular elements of tissue into
which the graft is to be placed, or alternatively, the plasticizer
is easily removed from the graft product prior to implantation.
Finally, the plasticizer is preferably compatible with and
preferably readily associates with the molecular elements of the
bone or soft tissue.
[0055] Plasticizers suitable for use in the present invention
include for example, a variety of biocompatible aqueous solutions.
Examples of acceptable plasticizers include, but are not restricted
to, members of the polyol family (sugar alcohols) of compounds
including C.sub.2 to C.sub.7 polyols, monoglycerides (such as
monoolein and monolinolein), and various short- and medium-chain
free fatty acids (such short-chain free fatty acids preferably
having a carbon chain length of less than six C, and such
medium-chain free fatty acids preferably having a carbon chain
length of from C.sub.12 to C.sub.14) and their corresponding
monoacylglycerol esters (MGs) such as the saturated MGs, ranging in
carbon chain length from C.sub.5 to C.sub.16, and preferably
C.sub.5 to C.sub.14 MGs. Specific plasticizers include, but are not
limited to, glycerol (glycerin USP), adonitol, sorbitol, ribitol,
galactitol, D-galactose, 1,3-dihydroxypropanol, ethylene glycol,
triethylene glycol, propylene glycol, glucose, sucrose, mannitol,
xylitol, meso-erythritol, adipic acid, pro line, hydroxyproline or
similar water-soluble small molecular weight solutes which can be
expected to replace water in the base matrix structure of bone or
soft tissue, and provide the hydrating functions of water in that
tissue. Other plasticizers suitable for use in the present
invention can be readily selected and employed by one of ordinary
skill in the art to which the present invention pertains without
undue experimentation depending on the desired clinical outcome,
sensitivity of the implantation procedure, patient sensitivities,
and physician choice.
[0056] The present plasticizers are preferably employed at a
concentration in the range of from 0.1 to 2.0 M, 10% to 100% by
weight/volume, or 3% to 30% by weight of bone or soft tissue. The
use of Molar concentrations and weight/volume percentages to
express preferred concentration ranges are intended to deal with
the concentrations of these plasticizers in the solutions used to
treat the tissues. The use of the weight percent of plasticizer in
load-bearing bone or soft tissue is intended to deal with the
effective quantity of a given plasticizer in the load-bearing
tissue which is necessary to effectively replace the waters of
hydration present in the unprocessed tissues which are maximally
plasticized to a state approximating normal tissue. The plasticizer
can be introduced into the bone or soft tissue matrix at any number
of steps in the processing procedures and at a variety of
concentrations with and without the use of permeation
enhancers.
[0057] The result(s) of plasticization of load-bearing bone and
soft tissue products are bone or soft tissue products which are
similar to traditionally dehydrated bone and soft tissue products
in residual moisture but are not subject to fractures or micro
fractures like such dehydrated products, yet do not need to be
rehydrated prior to use. The mechanical and use properties of a
plasticized bone or soft tissue product are similar to those of
natural (fresh autogenous and/or fresh-frozen allograft) bone,
dura, pericardium, fascia, ligaments, and tendons.
[0058] III. Graft Cleaning and Processing
[0059] The present plasticizers may be introduced to the bone or
soft tissue products at several points in the processing
procedure(s). Bone processing and cleaning procedures suitable for
use with the present invention include known processes, as well as
the processes described in U.S. Pat. No. 5,556,379 and co-pending
U.S. patent application Ser. No. 08/871,601 "Process for Cleaning
Grafts Using Centrifugal Force and Bone Grafts Produced Thereby";
Ser. No. 08/620,858 "Composition for Cleaning Bones"; Ser. No.
08/646,520 "Recirculation Method for Cleaning Essentially Intact
Bone Grafts Using Pressure Mediated Flow of Solutions and Bone
Grafts Produced Thereby"; and Ser. No. 08/646,519 "Ultrasonic
Cleaning of Allograft Bone" which are hereby incorporated herein in
their entirety. The plasticizers may be incorporated into the
processing procedure(s) using steps where the plasticizer(s) is/are
present at essentially fill strength, i.e. 100% concentration, in
the presence and/or absence of permeation enhancers, and at
concentrations less than fill strength.
[0060] Bone tissue is cleaned and processed as described in U.S.
Pat. No. 5,556,379, and co-pending U.S. patent application Ser.
Nos. 08/871,601; 08/620,858; 08/646,520; and 08/646,519 by for
example, transection of an essentially intact bone or perforation
of an essentially intact bone with attachment of sterile plastic
tubing to the cut end of a transected bone or to an attachment port
inserted into the perforation of the perforated bone. The bone is
immersed in a cleaning solution, such solutions including known
cleaning agents as well as those described in the above-identified
patent and co-pending patent applications, with or without use of
sonication. The cleaning solution is induced to flow into, through,
and out of the bone through use of a peristaltic pump or negative
pressure applied to the cleaning solution. The induced flow of
cleaning solution draws the bone marrow from the interior of the
bone, and particularly from the cancellous bone marrow space, where
it can be safely deposited in a receiving container containing a
strong virucidal agent such as sodium hypochlorite (common bleach).
The cleaned bone can then be further cleaned by causing the
cleaning solution to be replaced with a solution of one or more
decontaminating agents, including for example 3% hydrogen peroxide,
with or without plasticizer. Hydrogen peroxide which in addition to
its mild disinfection activity generates oxygen bubbles that can
further assist in dislodging residual bone marrow materials causing
the residual bone marrow materials to flow from the bone and into
the receiving container.
[0061] In the above-described process, after processing with the
cleaning solution, after processing with a decontaminating agent,
in place of processing with a decontaminating agent, or after
dehydration, the cleaned graft is plasticized for example, by
processing the cleaned graft with a plasticizer composition
containing one or more plasticizers including for example glycerin
USP in a solvent.
[0062] IV. Plasticization
[0063] Bone and soft tissue grafts can be cleaned and processed
using conventional methods, including those described in. When
processing using these methods the graft is plasticized by adding
one or more plasticizers or a plasticizer composition to processing
steps after bone cleaning is essentially completed, and prior to
freeze-drying. Under freeze-drying, the water present in the bone
(or smaller cut bone grafts produced form the essentially intact
bone) is removed by sublimation, however, the glycerol will remain
and replace the free and bound water as the water is removed from
the bone tissue. The one or more plasticizer(s) is added to fully
hydrated bone tissue and the plasticizer(s) are induced to
penetrate into the bone tissue optionally using a permeation
enhancer. Thus, the bone or soft tissue is dehydrated yet the
materials properties of the bone tissue will be similar to the
materials properties of normal bone or soft tissue, i.e. partially
or fully hydrated bone or soft tissue. The produced plasticized
bone or soft graft contains minimal quantities of the
plasticizer(s) and can be removed from the package and directly
implanted into a patient without rehydration. If the presence of
these small quantities of glycerol is of concern, the bone or soft
tissue grafts may be quickly rinsed and/or washed in sterile saline
just prior to implantation.
[0064] Bone or soft tissue cleaned and processed by the methods as
described for bone cleaning and processing in U.S. Pat. No.
5,556,379, and/or co-pending U.S. patent application Ser. Nos.
08/871,601; 08/620,858; 08/646,520; and/or 08/646,519 and/or bone
or soft tissue cleaned and processed by conventional methods, may
be plasticized by processing with the plasticizer composition
containing one or more plasticizers, including for example glycerin
USP, in a solvent by for example drawing the plasticizer
composition into the bone. Suitable solvents include for example,
70% isopropyl alcohol. The 70% isopropyl alcohol/plasticizer
composition can be prepared by diluting absolute (100%) isopropyl
alcohol with the one or more plasticizers, including for example
glycerin USP such that the plasticizer accounts for 30% of the
total volume, and isopropyl alcohol accounts for 70% of the total
volume. Under this method, the original processing procedures as
described in U.S. Pat. No. 5,556,379 regarding the use of 70%
isopropyl alcohol, is retained essentially unchanged. The isopropyl
alcohol facilitates penetration of the glycerol into the tissue by
acting as a permeation enhancer and the glycerol more readily
penetrates the tissue due to the reduced surface tension of the
alcoholic solution. The induced flow of glycerol/isopropyl alcohol
into, through, and out of for example, the essentially intact bone,
further serves to remove residual cellular elements, for example
bone marrow materials, if any. It also allows penetration of the
glycerol/isopropyl alcohol solution into the most remote areas of
the tissue, and facilitates a uniform distribution of the glycerol
into the tissue. The isopropyl alcohol can be removed from the
tissue by washing with a washing solution including sterile water,
for example as described in U.S. Pat. No. 5,556,379 following the
alcohol processing step. Preferably, the washing solution includes
glycerin USP (30% volume:volume). The washing solution facilitates
removal of the isopropyl alcohol without removal of the glycerin
USP. The cleaned and plasticized tissue can then be frozen and
freeze-dried or dehydrated according to standard protocols.
[0065] Alternatively, bone or soft tissue grafts may be plasticized
after cleaning and freeze-drying. For example, tissue can be
processed and cleaned according to any method including known
methods, or as described in U.S. Pat. No. 5,556,379 described
above. After the sterile water wash the tissue (for example bone
tissue) is cleaned of virtually all cellular elements (for example,
bone marrow) present in the tissue and the cleaned tissue can be
further processed into for example, small cut bone grafts, and
dehydrated or freeze-dried (also called lyophilized) using standard
methods well known to those skilled in the art. Freeze-dried or
dehydrated tissue grafts preferably contain less than about 5%
residual moisture, satisfying the definition of freeze-dried bone
allografts as prescribed under Standards of the American
Association of Tissue Banks.
[0066] Clean freeze-dried or dehydrated bone or soft tissue grafts
are plasticized by processing the tissue graft with a plasticizer
composition, suitable compositions including for example 70%
isopropyl alcohol/30% glycerin USP or 100% glycerin USP. Due to the
presence of air in the cancellous and cortical bone spaces, the
plasticizer(s) may only penetrate into the bone tissue with which
it is in physical contact. Suitable methods for achieving physical
contact between the plasticizer and bone or soft tissue include
those methods known to one of ordinary skill in the art to which
the present invention pertains. The plasticizer composition can be
induced to flow into the cancellous and cortical bone spaces of
bone tissue, or soft tissue, thus achieving physical contact, by
various known methods that can be readily selected and employed by
one of ordinary skill in the art to which the present invention
pertains without undue experimentation, and include for example,
agitation of the a tissue with the plasticizer composition,
application of a vacuum (5 to 500 mTorr) above the plasticizer. The
vacuum induces the air trapped in the, for example cancellous and
cortical bone spaces/tissue to exit and be carried off. As the
trapped air is removed from the cancellous and cortical bone
spaces/tissue, the plasticizer quickly moves into the spaces
previously occupied by air greatly enhancing penetration of the
plasticizer into the bone or soft tissue. The plasticizer fills the
spaces previously occupied by the free and bound water restoring
the tissue to a materials property similar to that materials
property of the original fully or partially hydrated tissue (e.g.
normal bone).
[0067] The present one or more plasticizers may be introduced to
soft tissue products at several points in the processing
procedures, but are preferably introduced prior to the
freeze-drying or dehydrating step. By introducing plasticizers
prior to freeze-drying or dehydrating, the derived soft tissue
graft is in a freeze-dried/dehydrated state where the plasticizer
is used to stabilize the matrix and load bearing components of the
soft tissue graft such that the graft can be used without
rehydration/reconstitution.
[0068] V. Transplantation into a Patient
[0069] Prior to transplantation into a patient, excess glycerol may
optionally be removed from the plasticized bone or soft tissue
graft using for example, the method described in co-pending U.S.
patent application Ser. No. 08/871,601. Specifically, the
plasticized grafts are placed into centrifuge vessels/containers
and on top of inserts designed to keep the bone grafts off of the
bottom of the containers. The grafts are then centrifuged at 1,000
to 2,000 revolutions per minute (rpm) for 10-20 minutes. The excess
glycerol or similar plasticizer exits the grafts and collects in
the bottom of the centrifuge containers away from the grafts. The
plasticizer tightly associated with the molecular and chemical
structure of the tissue will not exit the graft and the tissue will
remain plasticized without retaining physically discernable
quantities of plasticizer. The plasticized graft(s) may then be
packaged directly or packaged in a packaging format which permits
application of a vacuum to the container. The current value of
using a packaging format which permits storage of grafts under
vacuum lies in the ability to predict possible loss of sterility
with loss of vacuum to the packaging.
[0070] Clinical usage of plasticized bone or soft tissue grafts
includes direct implantation of the grafts without further
processing following removal from the packaging, implantation
following a brief washing in sterile isotonic saline to remove any
remaining traces of plasticizer associated with the immediate
surfaces of the grafts, or by implantation following an extended
(approximately 1 hour) washing with sterile isotonic saline to
remove as much plasticizer as possible. Under any of the above
described further processing of grafts, the materials properties of
the plasticized grafts resemble those materials properties of fully
or partially hydrated natural tissue (i.e. normal bone or soft
tissue). The produced plasticized graft does not need to be
rehydrated prior to clinical implantation, yet retains the strength
and compressive/tensile properties of natural tissue. Plasticized
freeze-dried soft tissue grafts where the plasticizer is used to
stabilize the matrix and load bearing components of the soft tissue
graft, can also be directly implanted in a patient without
rehydration/reconstitution.
[0071] Suitable surgical methods for implanting bone and soft
tissue grafts into a patient are well known to those of ordinary
skill in the art to which the present invention pertains, and such
methods are equally applicable to implantation of the present
plasticized grafts. Those of ordinary skill in the art to which the
present invention pertains can readily determine, select and employ
suitable surgical methods without undue experimentation.
[0072] Further details of the process of the invention are
presented in the examples that follow:
EXAMPLE 1
[0073] Processing of a Frozen Distal Femur
[0074] A. Cleaning and Processing: A frozen distal femur is
selected and all of the soft tissue and periosteum is removed using
sharp dissection techniques and periosteal elevators. The graft is
then transected to the desired length using a Stryker.TM. saw or
band saw. Each bisected piece is not more than 30 cm in length and
is straight and contains no bone fragments. The surface cartilage
is then removed from the femoral condyle with either a scalpel
blade, periosteal elevator, or osteotome. The processing
instructions dictate leaving the cartilage "on" when appropriate.
Using a 3/8" drill bit, the cut end of the shaft is drilled
approximately 5 cm. The interior of the intramedullary canal is
then thoroughly washed with the lavage system.
[0075] An intercalary fitting is then inserted by screwing the
threaded, tapered end into the cut end of the graft. The vacuum
tubing is assembled by securing one end of the tubing to the nipple
end of the intercalary fitting. The other end of the tubing is
secured to the piston driven pump. Finally, another section of
vacuum tubing is secured to the other side of the piston pump.
Approximately 4000 cc of a 1:100 dilution of the "Allowash.TM.
Solution" is poured into the sterile flushing vessel. The
"Allowash.TM. Solution" is prepared by adding 4 cc of cleaning
reagent to 3996 cc of sterile water. The flushing vessel is labeled
as "Allowash.TM. Solution." The open end of the second piece of
vacuum tubing is placed into a graduated flask. The piston pump is
set to "reverse" and the flow rate controller is set to 50%. The
pump is turned on and at least 500 cc of the first solvent
(Allowash.TM. Solution) is drawn to waste. Thereafter, the open end
of the second piece of vacuum tubing is removed from the graduated
flask and placed into the sterile flushing vessel. The drive is
maintained in the "reverse" position at 50%. The Allowash Solution
recirculates for a minimum of 15 minutes.
[0076] The 1:100 dilution of the Allowash.TM. Solution is then
decanted and approximately 4 liters of 3% hydrogen peroxide is
added to the flushing vessel. The piston pump is set to reverse and
the flow rate controller is set to 50%. The pump is then turned on
and at least 500 cc of the 3% hydrogen peroxide solution is drawn
to waste. Thereafter, the open end of the second piece of vacuum
tubing is removed from the graduated flask and placed it into the
sterile flushing vessel. The drive is maintained in the reverse
position at 50%. The hydrogen peroxide is then allowed to
recirculate for a minimum of 15 minutes.
[0077] The hydrogen peroxide is then decanted and approximately
3980 cc of sterile water is added along with the entire contents of
reconstituted vials of Bacitracin and Polyrnyxin B to the flushing
vessel. The flushing vessel is clearly labeled "antibiotic." The
piston pump is then set to reverse and the flow rate controller is
set at 50%. The pump is turned on and at least 500 cc of antibiotic
solution is drawn to waste. The open end of the second piece of
vacuum tubing is removed from the graduated flask and placed into
the sterile flushing vessel. The drive is maintained in the reverse
position at 50%. The antibiotic solution is allowed to recirculate
for a minimum of 15 minutes.
[0078] B. Plasticization: The antibiotic solution is then decanted
and approximately 4 liters of 70% isopropyl alcohol/30% glycerin
USP is added to the flushing vessel. The flushing vessel is clearly
labeled as 70% IPA/30% glycerin USP. The piston pump is set to
reverse and the flow rate controller is set to 50%. The pump is
turned on and at least 500 cc of IPA/glycerin USP solution is drawn
to waste.
[0079] The open end of the second piece of vacuum tubing is removed
from the graduated flask and placed into the sterile flushing
vessel. The drive is maintained in the reverse position and the
flow controller is set to 50%. The IPA/glycerin USP is allowed to
recirculate for a minimum of 30 minutes. The IPA/glycerin USP
solution is decanted and 4 liters of 30% glycerin USP in sterile
water is added to the flushing vessel. The flushing vessel is
labeled as glycerin USP washing solution. The piston pump is set to
reverse and the flow rate controller is set to 50%. The pump is
turned on and at least 500 cc of washing solution is drawn to
waste.
[0080] The open end of the second piece of vacuum tubing is removed
from the graduated flask and placed into the sterile flushing
vessel. The drive is maintained in the reverse position and the
flow rate controller is set to 50%. The washing solution is allowed
to recirculate for a minimum of 15 minutes. Thereafter, the bone
graft is removed from the flushing vessel and processed for
freeze-drying as per standard operating procedure.
EXAMPLE 2
[0081] Processing of a Frozen Distal Femur
[0082] A. Cleaning and Processing: A frozen distal femur is
selected and all of the soft tissue and periosteum is removed using
sharp dissection techniques and periosteal elevators. The graft is
then transected to the desired length using a Stryker.TM. saw or
band saw. Each bisected piece is not more than 30 cm in length and
is straight and contains no bone fragments. The surface cartilage
is then removed from the femoral condyle with either a scalpel
blade, periosteal elevator, or osteotome. The processing
instructions dictate leaving the cartilage "on" when appropriate.
Using a 3/8" drill bit, the cut end of the shaft is drilled
approximately 5 cm. The interior of the intramedullary canal is
then thoroughly washed with the lavage system.
[0083] An intercalary fitting is then inserted by screwing the
threaded, tapered end into the cut end of the graft. The vacuum
tubing is assembled by securing one end of the tubing to the nipple
end of the intercalary fitting. The other end of the tubing is
secured to the piston driven pump. Finally, another section of
vacuum tubing is secured to the other side of the piston pump.
Approximately 4000 cc of a 1:100 dilution of the "Allowash.TM.
Solution" is poured into the sterile flushing vessel. The
"Allowash.TM. Solution" is prepared by adding 4 cc of cleaning
reagent The flushing vessel is labeled as "Allowash.TM. Solution."
The open end of the second piece of vacuum tubing is placed into a
graduated flask. The piston pump is set to "reverse" and the flow
rate controller is set to 50%. The pump is turned on and at least
500 cc of the first solvent (Allowash Solution) is drawn to waste.
Thereafter, the open end of the second piece of vacuum tubing is
removed from the graduated flask and placed into the sterile
flushing vessel. The drive is maintained in the "reverse" position
at 50%. The Allowash Solution recirculates for a minimum of 15
minutes.
[0084] B. Plasticization: The 1:100 dilution of the Allowash.TM.
Solution is decanted and approximately 4 liters of 3% hydrogen
peroxide/30% glycerin USP is added to the flushing vessel. The
piston pump is set to reverse and the flow rate controller is set
to 50%. The pump is turned on and at least 500 cc of the 3%
hydrogen peroxide/glycerin USP solution is drawn to waste. The open
end of the second piece of vacuum tubing is removed from the
graduated flask and placed into the sterile flushing vessel. The
drive is maintained in the reverse position. The hydrogen
peroxide/glycerin USP is allowed to recirculate for a minimum of 15
minutes.
[0085] The hydrogen peroxide/glycerin USP is then decanted and
approximately 3980 cc of sterile water is added along with the
entire contents of reconstituted vials of Bacitracin and Polymyxin
B prepared in a water solution of 30% glycerin USP, to the flushing
vessel. The flushing vessel is clearly labeled "antibiotic." The
piston pump is then set to reverse and the flow rate controller is
set at 50%. The pump is turned on and at least 500 cc of antibiotic
solution is drawn to waste. The open end of the second piece of
vacuum tubing is removed from the graduated flask and placed into
the sterile flushing vessel. The drive is maintained in the reverse
position at 50%. The antibiotic solution is allowed to recirculate
for a minimum of 15 minutes.
[0086] The antibiotic solution is then decanted and approximately 4
liters of 70% isopropyl alcohol/30% glycerin USP is added to the
flushing vessel. The flushing vessel is clearly labeled as 70%
IPA/30% glycerin USP. The piston pump is set to reverse and the
flow rate controller is set to 50%. The pump is turned on and at
least 500 cc of IPA/glycerin USP solution is drawn to waste.
[0087] The open end of the second piece of vacuum tubing is removed
from the graduated flask and placed into the sterile flushing
vessel. The drive is maintained in the reverse position and the
flow controller is set to 50%. The IPA/glycerin USP is allowed to
recirculate for a minimum of 30 minutes. The IPA/glycerin USP
solution is decanted and 4 liters of 30% glycerin USP in sterile
water is added to the flushing vessel. The flushing vessel is
labeled as glycerin USP washing solution. The piston pump is set to
reverse and the flow rate controller is set to 50%. The pump is
turned on and at least 500 cc of washing solution is drawn to
waste.
[0088] The open end of the second piece of vacuum tubing is removed
from the graduated flask and placed into the sterile flushing
vessel. The drive is maintained in the reverse position and the
flow rate controller is set to 50%. The washing solution is allowed
to recirculate for a minimum of 15 minutes. Thereafter, the bone
graft is removed from the flushing vessel and processed for
freeze-drying as per standard operating procedure.
EXAMPLE 3
[0089] Processing of a Frozen Distal Femur
[0090] A. Cleaning and Processing: A frozen distal femur is
selected and all of the soft tissue and periosteum is removed using
sharp dissection techniques and periosteal elevators. The graft is
then transected to the desired length using a Stryker.TM. saw or
band saw. Each bisected piece is not more than 30 cm in length and
is straight and contains no bone fragments. The surface cartilage
is then removed from the femoral condyle with either a scalpel
blade, periosteal elevator, or osteotome. The processing
instructions dictate leaving the cartilage "on" when appropriate.
Using a 3/8" drill bit, the cut end of the shaft is drilled
approximately 5 cm. The interior of the intramedullary canal is
then thoroughly washed with the lavage system.
[0091] An intercalary fitting is then inserted by screwing the
threaded, tapered end into the cut end of the graft. The vacuum
tubing is assembled by securing one end of the tubing to the nipple
end of the intercalary fitting. The other end of the tubing is
secured to the piston driven pump. Finally, another section of
vacuum tubing is secured to the other side of the piston pump.
Approximately 4000 cc of a 1:100 dilution of the "Allowash.TM.
Solution" is poured into the sterile flushing vessel. The
"Allowash.TM. Solution" is prepared by adding 4 cc of cleaning
reagent. The flushing vessel is labeled as "Allowash.TM. Solution."
The open end of the second piece of vacuum tubing is placed into a
graduated flask. The piston pump is set to "reverse" and the flow
rate controller is set to 50%. The pump is turned on and at least
500 cc of the first solvent (Allowash Solution) is drawn to waste.
Thereafter, the open end of the second piece of vacuum tubing is
removed from the graduated flask and placed into the sterile
flushing vessel. The drive is maintained in the "reverse" position
at 50%. The Allowash Solution recirculates for a minimum of 15
minutes.
[0092] The 1:100 dilution of the Allowash.TM. Solution is then
decanted and approximately 4 liters of 3% hydrogen peroxide is
added to the flushing vessel. The piston pump is set to reverse and
the flow rate controller is set to 50%. The pump is then turned on
and at least 500 cc of the 3% hydrogen peroxide solution is drawn
to waste. Thereafter, the open end of the second piece of vacuum
tubing is removed from the graduated flask and placed it into the
sterile flushing vessel. The drive is maintained in the reverse
position at 50%. The hydrogen peroxide is then allowed to
recirculate for a minimum of 15 minutes.
[0093] The hydrogen peroxide is then decanted and approximately
3980 cc of sterile water is added along with the entire contents of
reconstituted vials of Bacitracin and Polymyxin B to the flushing
vessel. The flushing vessel is clearly labeled "antibiotic." The
piston pump is then set to reverse and the flow rate controller is
set at 50%. The pump is turned on and at least 500 cc of antibiotic
solution is drawn to waste. The open end of the second piece of
vacuum tubing is removed from the graduated flask and placed into
the sterile flushing vessel. The drive is maintained in the reverse
position at 50%. The antibiotic solution is allowed to recirculate
for a minimum of 15 minutes.
[0094] The antibiotic solution is then decanted and approximately 4
liters of 70% isopropyl alcohol (IPA) is added to the flushing
vessel. The flushing vessel is labeled as 70% IPA. The piston pump
is set to reverse and the flow rate controller is set to 50%. The
pump is turned on and at least 500 cc of IPA solution is drawn to
waste. The open end of the second piece of vacuum tubing is removed
from the graduated flask and placed into the sterile flushing
vessel. The drive is maintained in the reverse position and the
flow controller is set to 50%. The IPA recirculates for a minimum
of 15 minutes. The IPA solution is then decanted and 4 liters of
sterile water is added to the flushing vessel. The flushing vessel
is labeled as "washing solution." The piston pump is set to reverse
and the flow rate controller is set to 50%. The pump is turned on
and at least 500 cc of washing solution is drawn to waste.
[0095] The open end of the second piece of vacuum tubing is removed
from the graduated flask and placed into the sterile flushing
vessel. The drive is maintained in the reverse position and the
flow rate controller is set to 50%. The washing solution
recirculates for a minimum of 15 minutes. The bone graft is removed
from the flushing vessel and processed for freeze-drying as per
standard operating procedure.
[0096] B. Plasticization: The freeze-dried bone graft(s) are then
placed into sterile glycerin USP such that they are totally
immersed in the viscous glycerol. Vacuum (10 to 500 mTorr,
preferably 100 to 200 mTorr) is applied to the container until
bubbles cease to exit the bone graft (about 5 to 60 minutes
depending on the size and configuration of the bone graft,
preferably about 20 to 30 minutes). The bone graft(s) are then
removed from the glycerin USP solution and placed into an
appropriate centrifuge container on top of a graft support.
[0097] The bone graft(s) are centrifuged at about 1000 to 2000 rpm
until the glycerol ceases to exit the bone graft and accumulate in
the bottom of the centrifuge container (usually 5 to 60 minutes
depending on the size and configuration of the bone graft,
preferably about 5 to 15 minutes). The bone graft(s) are then
removed from their respective centrifuge containers and packaged
for distribution.
EXAMPLE 4
[0098] Processing Cloward Dowels
[0099] A. Cleaning and Processing: Graft material is selected and
all of the soft tissue and periosteum is removed from the distal
femur, proximal and distal tibia, and cartilage is removed from the
site. The femur is transected 10-15 cm above the femoral condyles
and the distal femoral condyles are bisected. Transect the proximal
tibia 10-15 cm below the tibial plateau. The distal femur or
proximal tibia is placed in a Pan-A-Vise.TM.. This is accomplished
by removing a section of the diaphysis, allowing the vise jaws to
grip the tissue securely. The Cloward set (12, 14, 16, 18, or 20
mm) is then assembled: 1. Place the extractor assembly within the
cutter shaft, 2. Screw the cutter assembly onto the shaft with the
aid of the Cloward set wrench, 3. Screw the set-point onto the
extractor assembly, 4. Insert the shaft of the Cloward set into the
3/8" variable speed drill and tighten the chuck with the key. The
set-point is then placed and locked at the forward aspect of the
cutter.
[0100] The apparatus is then placed on the tissue to be fashioned.
Drilling is commenced at a moderate speed. After the set-point has
made a deep cut in the tissue, and the teeth have begun to cut into
the tissue, drilling is stopped, and the set-point apparatus is
unlocked. Drilling is continued using the marks created as a
guide.
[0101] The Cloward(s) are then removed from the tissue block. A
Stryker.TM. saw or band saw is then used to remove the cut grafts
after all have been cut. Any cartilage is then trimmed from the
cortical face of the Cloward(s) using a scalpel and a #10 blade.
The distal end of the graft is then trimmed perpendicular to the
body of the graft with a band saw making sure the fashioned graft
is at least 15 mm long. The Cloward(s) are cleansed using pulsatile
water apparatus. If the surface marrow is not easily removed, dry
spin the graft(s) at 2600 rpm for 3 minutes.
[0102] The Cloward(s) are then placed in a sterile container with
hydrogen peroxide (3%) at 37 to 44.degree. C. The container is
sealed and the container is placed into the centrifuge. The
centrifuge is then balanced. The grafts are then centrifuged at
2600 rpm for 15 minutes. The tissue is removed from the centrifuge
and the rafts are placed into an ultrasonic cleaner. Equal volumes
of Allowash.TM. Solution, hydrogen peroxide (3%), and antibiotics
are added to the ultrasonic cleaner and sonicate the tissue at
37-44.degree. C. for a minimum of 1 hour. Thereafter, the tissue is
removed from the ultrasonic cleaner.
[0103] The mixture is decanted and a sterile glass container is
filled with fresh 3% hydrogen peroxide. The grafts are then placed
in the container, the top is sealed and the container is taken to
the large ultrasonic cleaner. The grafts are then sonicated for 90
minutes. Thereafter, the grafts are incubated overnight at
37-44.degree. C. (minimum of 6 hours, preferably 12 to 18
hours).
[0104] B. Plasticization: After incubation, the hydrogen peroxide
is decanted and the basin is filled with 70% isopropyl alcohol/30%
glycerin USP and the grafts are incubated at room temperature for a
minimum of 30 minutes. Thereafter, the isopropyl alcohol/glycerin
USP solution is decanted and the container is filled with warm 30%
glycerin USP in water. The grafts are incubated for a minimum of 30
minutes. Methods of incubation include for example: soaking.
[0105] The glycerin solution is then decanted and the Cloward
dowels are removed from the container. The Cloward dowels are then
placed into a sterile container. The container is sealed and placed
into the centrifuge. The centrifuge is balanced and the grafts are
centrifuged for 3-5 minutes to dry, and the remaining solution is
removed.
[0106] The width and length of the Cloward(s) are measured, raft
identification numbers are assigned, and the information is
recorded on the "Tissue Processing Log Worksheet". One graft is
then placed into a glass, 120 cc bottle and the printed label is
affixed with the unique numeric designator. This step is repeated
until all deposits are bottled. The bottled grafts are either
frozen and packaged, or frozen and freeze-dried and packaged.
EXAMPLE 5
[0107] Processing Cloward Dowels
[0108] A. Cleaning and Processing: Graft material is selected and
all of the soft tissue and periosteum is removed from the distal
femur, proximal and distal tibia, and cartilage is removed from the
site. The femur is transected 10-15 cm above the femoral condyles
and the distal femoral condyles are bisected. Transect the proximal
tibia 10-15 cm below the tibial plateau. The distal femur or
proximal tibia is placed in a Pan-A-Vise.TM.. This is accomplished
by removing a section of the diaphysis, allowing the vise jaws to
grip the tissue securely. The Cloward set (12, 14, 16, 18, or 20
mm) is then assembled: 1. Place the extractor assembly within the
cutter shaft, 2. Screw the cutter assembly onto the shaft with the
aid of the Cloward set wrench, 3. Screw the set-point onto the
extractor assembly, 4. Insert the shaft of the Cloward set into the
3/8" variable speed drill and tighten the chuck with the key. The
set-point is then placed and locked at the forward aspect of the
cutter.
[0109] The apparatus is then placed on the tissue to be fashioned.
Drilling is commenced at a moderate speed. After the set-point has
made a deep cut in the tissue, and the teeth have begun to cut into
the tissue, drilling is stopped, and the set-point apparatus is
unlocked. Drilling is continued using the marks created as a
guide.
[0110] The Cloward(s) are then removed from the tissue block. A
Stryker.TM. saw or band saw is then used to remove the cut grafts
after all have been cut. Any cartilage is then trimmed from the
cortical face of the Cloward(s) using a scalpel and a #10 blade.
The distal end of the graft is then trimmed perpendicular to the
body of the graft with a band saw making sure the fashioned graft
is at least 15 mm long. The Cloward(s) are cleansed using pulsatile
water apparatus. If the surface marrow is not easily removed, dry
spin the graft(s) at 2600 rpm for 3 minutes.
[0111] B. Plasticization: The Cloward(s) are then placed in a
sterile container with hydrogen peroxide (3%) and glycerin USP
(30%) at 37 to 44.degree. C. The container is sealed and the
container is placed into the centrifuge. The centrifuge is then
balanced. The grafts are then centrifuged at 2600 rpm for 15
minutes. The tissue is removed from the centrifuge and the grafts
are placed into an ultrasonic cleaner. Equal volumes of
Allowash.TM. Solution, hydrogen peroxide (3%), 30% glycerin USP,
and antibiotics are added to the ultrasonic cleaner and the tissue
is sonicated at 37-44.degree. C. for a minimum of 1 hour.
Thereafter, the tissue is removed from the ultrasonic cleaner.
[0112] The mixture is decanted and a sterile glass container is
filled with fresh 3% hydrogen peroxide/30% glycerin USP. The grafts
are then placed in the container, the top is sealed and the
container is taken to the large ultrasonic cleaner. The grafts are
then sonicated for 90 minutes.
[0113] Thereafter, the grafts are incubated overnight at
37-44.degree. C. (minimum of 6 hours, preferably 12 to 18
hours).
[0114] After incubation, the hydrogen peroxide is decanted and the
basin is filled with 70% isopropyl alcohol/30% glycerin USP and the
grafts are incubated at room temperature for a minimum of 30
minutes. Thereafter, the isopropyl alcohol/glycerin USP solution is
decanted and the container is filled with warm 30% glycerin USP in
water. The grafts are incubated for a minimum of 30 minutes.
Methods of incubation include for example: soaking and mild
agitation.
[0115] The glycerin solution is then decanted and the Cloward
dowels are removed from the container. The Cloward dowels are then
placed into a sterile container. The container is sealed and placed
into the centrifuge. The centrifuge is balanced and the grafts are
centrifuged for 3-5 minutes to dry, and the remaining solution is
removed.
[0116] The width and length of the Cloward(s) are measured, graft
identification numbers are assigned, and the information is
recorded on the "Tissue Processing Log Worksheet". One graft is
then placed into a glass, 120 cc bottle and the printed label is
affixed with the unique numeric designator. This step is repeated
until all deposits are bottled. The bottled grafts are either
frozen and packaged, or frozen and freeze-dried and packaged.
EXAMPLE 6
[0117] Processing Cloward Dowels
[0118] A. Cleaning and Processing: Graft material is selected and
all of the soft tissue and periosteum is removed from the distal
femur, proximal and distal tibia, and cartilage is removed from the
site. The femur is transected 10-15 cm above the femoral condyles
and the distal femoral condyles are bisected. Transect the proximal
tibia 10-15 cm below the tibial plateau. The distal femur or
proximal tibia is placed in a Pan-A-Vise.TM.. This is accomplished
by removing a section of the diaphysis, allowing the vise jaws to
grip the tissue securely. The Cloward set (12, 14, 16, 18, or 20
mm) is then assembled: 1. Place the extractor assembly within the
cutter shaft, 2. Screw the cutter assembly onto the shaft with the
aid of the Cloward set wrench, 3. Screw the set-point onto the
extractor assembly, 4. Insert the shaft of the Cloward set into the
{fraction (3/8)}" variable speed drill and tighten the chuck with
the key. The set-point is then placed and locked at the forward
aspect of the cutter.
[0119] The apparatus is then placed on the tissue to be fashioned.
Drilling is commenced at a moderate speed. After the set-point has
made a deep cut in the tissue, and the teeth have begun to cut into
the tissue, drilling is stopped, and the set-point apparatus is
unlocked. Drilling is continued using the marks created as a
guide.
[0120] The Cloward(s) are then removed from the tissue block. A
Stryker.TM. saw or band saw is then used to remove the cut grafts
after all have been cut. Any cartilage is then trimmed from the
cortical face of the Cloward(s) using a scalpel and a #10 blade.
The distal end of the graft is then trimmed perpendicular to the
body of the graft with a band saw making sure the fashioned graft
is at least 15 mm long. The Cloward(s) are cleansed using pulsatile
water apparatus. If the surface marrow is not easily removed, dry
spin the graft(s) at 2600 rpm for 3 minutes.
[0121] The Cloward(s) are then placed in a sterile container with
hydrogen peroxide (3%) at 37 to 44.degree. C. The container is
sealed and the container is placed into the centrifuge. The
centrifuge is then balanced. The grafts are then centrifuged at
2600 rpm for 15 minutes. The tissue is removed from the centrifuge
and the grafts are placed into an ultrasonic cleaner. Equal volumes
of Allowash.TM. Solution, hydrogen peroxide (3%), and antibiotics
are added to the ultrasonic cleaner and sonicate the tissue at
37-44.degree. C. for a minimum of 1 hour. Thereafter, the tissue is
removed from the ultrasonic cleaner.
[0122] The mixture is decanted and a sterile glass container is
filled with fresh 3% hydrogen peroxide. The grafts are then placed
in the container, the top is sealed and the container is taken to
the large ultrasonic cleaner. The grafts are then sonicated for 90
minutes. Thereafter, the grafts are incubated overnight at
37-44.degree. C. (minimum of 6 hours, preferably 12 to 18
hours).
[0123] After incubation, the hydrogen peroxide is decanted and the
basin is filled with 70% isopropyl alcohol and the grafts are
incubated at room temperature for a minimum of 30 minutes.
Thereafter, the isopropyl alcohol is decanted and the container is
filled with warm sterile water. The grafts are incubated for a
minimum of 30 minutes. Methods of incubation include for example:
soaking and mild agitation.
[0124] The wash solution is then decanted and the Cloward dowels
are removed from the container. The Cloward dowels are then placed
into a sterile container. The container is sealed and placed into
the centrifuge. The centrifuge is balanced. The grafts are then
centrifuged for 3-5 minutes to dry and the remaining solution is
removed.
[0125] The width and length of the Cloward(s) are measured, graft
identification numbers are assigned, and the information is
recorded on the "Tissue Processing Log Worksheet". One graft is
then placed into a glass, 120 cc bottle and the printed label is
affixed with the unique numeric designator. This step is repeated
until all deposits are bottled. The bottled grafts are either
frozen and packaged, or frozen and freeze-dried and packaged.
[0126] B. Plasticization: Viscous glycerol is then added to each
bottle sufficient to cover the graft and vacuum (10 to 500 mTorr)
is applied to each bottle until the air ceases to exit the grafts
(usually 5-20 minutes depending on graft type). The grafts are then
removed from the bottles and placed into a centrifuge container.
The grafts are centrifuged for 15-30 minutes or until glycerol
ceases to exit the grafts and accumulate in the space below the
grafts. The bottled grafts are either packaged or placed under
vacuum and packaged.
EXAMPLE 7
[0127] Processing Cloward Dowels
[0128] A. Cleaning and Processing: Graft material is selected and
all of the soft tissue and periosteum is removed from the distal
femur, proximal and distal tibia, and cartilage is removed from the
site. The femur is transected 10-15 cm above the femoral condyles
and the distal femoral condyles are bisected. Transect the proximal
tibia 10-15 cm below the tibial plateau. The distal femur or
proximal tibia is placed in a Pan-A-Vise.TM.. This is accomplished
by removing a section of the diaphysis, allowing the vise jaws to
grip the tissue securely. The Cloward set (12, 14, 16, 18, or 20
mm) is then assembled: 1. Place the extractor assembly within the
cutter shaft, 2. Screw the cutter assembly onto the shaft with the
aid of the Cloward set wrench, 3. Screw the set-point onto the
extractor assembly, 4. Insert the shaft of the Cloward set into the
{fraction (3/8)}" variable speed drill and tighten the chuck with
the key. The set-point is then placed and locked at the forward
aspect of the cutter.
[0129] The apparatus is then placed on the tissue to be fashioned.
Drilling is commenced at a moderate speed. After the set-point has
made a deep cut in the tissue, and the teeth have begun to cut into
the tissue, drilling is stopped, and the set-point apparatus is
unlocked. Drilling is continued using the marks created as a
guide.
[0130] The Cloward(s) are then removed from the tissue block. A
Stryker.TM. saw or band saw is then used to remove the cut grafts
after all have been cut. Any cartilage is then trimmed from the
cortical face of the Cloward(s) using a scalpel and a #10 blade.
The distal end of the graft is then trimmed perpendicular to the
body of the graft with a band saw making sure the fashioned graft
is at least 15 mm long. The Cloward(s) are cleansed using pulsatile
water apparatus. If the surface marrow is not easily removed, dry
spin the graft(s) at 2600 rpm for 3 minutes.
[0131] B. Plasticization: The Cloward(s) are then placed in a
sterile container with hydrogen peroxide (3%)/glycerin USP 30% at
37 to 44.degree. C. The container is sealed and the container is
placed into the centrifuge. The centrifuge is then balanced. The
grafts are then centrifuged at 2600 rpm for 15 minutes. The tissue
is removed from the centrifuge and the grafts are placed into an
ultrasonic cleaner. Equal volumes of Allowash.TM. Solution,
hydrogen peroxide (3%), and antibiotics are added to the ultrasonic
cleaner and sonicate the tissue at 37-44.degree. C. for a minimum
of 1 hour. Thereafter, the tissue is removed from the ultrasonic
cleaner.
[0132] The mixture is decanted and a sterile glass container is
filled with fresh 3% hydrogen peroxide. The grafts are then placed
in the container, the top is sealed and the container is taken to
the large ultrasonic cleaner. The grafts are then sonicated for 90
minutes. Thereafter, the grafts are incubated overnight at
37-44.degree. C. (minimum of 6 hours, preferably 12 to 18
hours).
[0133] After incubation, the hydrogen peroxide is decanted and the
basin is filled with 70% isopropyl alcohol/30% glycerin USP and the
grafts are incubated at room temperature for a minimum of 30
minutes. Thereafter, the isopropyl alcohol/glycerin USP solution is
decanted and the container is filled with warm 30% glycerin USP in
sterile water. The grafts are incubated for a minimum of 30
minutes. Methods of incubation include for example: soaking and
mild agitation.
[0134] The solution is then decanted and the Cloward dowels are
removed from the container. The Cloward dowels are then placed into
a sterile container. The container is sealed and placed into the
centrifuge. The centrifuge is balanced. The grafts are then
centrifuged for 3-5 minutes to dry and the remaining solution is
removed.
[0135] The width and length of the Cloward(s) are measured, graft
identification numbers are assigned, and the information is
recorded on the "Tissue Processing Log Worksheet". One graft is
then placed into a glass, 120 cc bottle and the printed label is
affixed with the unique numeric designator. This step is repeated
until all deposits are bottled. The bottled grafts are either
frozen and packaged, or frozen and freeze-dried and packaged.
EXAMPLE 8
[0136] Processing of an Iliac Crest Wedge
[0137] A. Cleaning and Processing: The soft tissue, periosteum, and
cartilage is removed from an ilium. The ilium is placed in a
Pan-A-Vise.TM. by removing a section of the ilium, allowing the
vise jaws to grip the tissue securely. A Stryker saw is assembled
with parallel cutting blades (12, 14, 16, 18, or 20 mm). The
set-point at the forward aspect of the cutter is placed and locked.
The apparatus is placed on the tissue to be fashioned and cutting
is begun at a moderate speed.
[0138] After the set-point has made a deep cut in the tissue, and
the teeth have begun to cut into the tissue, cutting is stopped,
and the set-point apparatus is checked. Cutting is continued using
the marks created as a guide. A Stryker.TM. saw or band saw is then
used to remove the cut grafts after all have been cut.
[0139] Any cartilage is trimmed from the cortical face of the
grafts(s) using a scalpel and a #10 blade. The distal end of the
graft perpendicular to the body of the graft is trimmed with a band
saw making sure the fashioned graft is at least 15 mm long. The
Grafts is then cleansed using a pulsatile water apparatus. If the
surface marrow is not easily removed, the graft(s) is dry spun at
2600 rpm for 3 minutes.
[0140] B. Plasticization: The Iliac Crest Wedge(s) are then placed
in a sterile container with hydrogen peroxide (3%) and glycerin USP
(30%) at 37 to 44.degree. C. The container is sealed and placed
into the centrifuge. The centrifuge is balanced. The grafts are
then centrifuged at 2600 rpm for 15 minutes. The tissue is removed
from the centrifuge and the grafts are placed into the ultrasonic
cleaner. Equal volumes of Allowash.TM. Solution, hydrogen peroxide
(3%), glycerin USP (30%), and antibiotics are added to the
ultrasonic cleaner, and the grafts are sonicated at 37-44.degree.
C. for a minimum of 1 hour.
[0141] The tissue is then removed from the ultrasonic cleaner. The
mixture is decanted and a sterile glass container is filled with
fresh 3% hydrogen peroxide/30% glycerin USP. The grafts are placed
in the container, the top is sealed and the container is taken to a
large ultrasonic cleaner. The grafts are sonicated for 90 minutes.
Thereafter, the grafts are incubated overnight at 37-44.degree. C.
(minimum of 6 hours, preferably for 12 to 18 hours). Methods of
incubation include for example: soaking and mild agitation.
[0142] The hydrogen peroxide/glycerin USP is then decanted and the
basin is filled with 70% isopropyl alcohol/30% glycerin USP. The
grafts are then incubated at room temperature for a minimum of 30
minutes. The isopropyl alcohol/glycerin USP solution is then
decanted and the container is filled with warm 30% glycerin USP in
water. The grafts are incubated for a minimum of 30 minutes.
[0143] The glycerin USP solution is then decanted and the Iliac
Crest Wedges are removed from the container. The Iliac Crest Wedges
are then placed into a sterile container. The container is sealed
and placed into the centrifuge. The centrifuge is balanced and the
grafts are centrifuged for 3-5 minutes to dry and the remaining
solution is removed.
[0144] The width and length of the Wedges are measured, graft
identification numbers are assigned, and the information is
recorded on the "Tissue Processing Log Worksheet". One graft is
then placed into a glass, 120 cc bottle and the printed label is
affixed with the unique numeric designator. This step is repeated
until all deposits are bottled. The bottled grafts are either
frozen and packaged, or frozen and freeze-dried and packaged.
EXAMPLE 9
[0145] Processing of Fascia Lata
[0146] A. Cleaning and Processing: Any remaining muscle tissue is
removed from the fascia lata. The fascia is placed with the
subcutaneous layer uppermost, on a clean, drape towel. Using blunt
dissection techniques, all of the fat and extraneous soft tissue is
removed from the graft material. The graft is kept moist with
sterile water to prevent desiccation during processing.
[0147] Any torn fibers are removed from the edges of the graft
material, and a graft rectangular in shape is created. The graft(s)
are then placed in a basin containing a 1:100 dilution of
Allowash.TM. Solution or other surfactant(s) for at least 15
minutes. The basin is labeled as Allowash.TM. Solution. The time of
exposure is recorded on the Tissue Processing Log Worksheet.
[0148] B. Plasticization: The graft(s) are placed into an empty
basin labeled "Rinse". The graft(s) are rinsed three time with
copious amounts of sterile water to remove any residual detergents.
Any sterile water which accumulates in the Rinse basin is discarded
The number of rinses is recorded on the Tissue Processing Log
Worksheet. The fashioned graft(s) are then placed in the basin
containing U.S.P. grade 70% isopropyl alcohol containing 30%
glycerin USP for 2-5 minutes. The basin is labeled IPA/Glycerin.
The time of exposure to the alcohol/glycerin USP solution is
recorded in the Tissue Processing Log Worksheet.
[0149] The graft(s) are then placed into the basin containing the
antibiotic solution in 30% glycerin USP for at least 15 minutes.
The basin is labeled as Antibiotics/Glycerin USP. The exposure time
to the antibiotics/glycerin USP is recorded on the Tissue
Processing Log Worksheet. The graft(s) are then thoroughly soaked
by immersing each deposit into sterile 30% glycerin USP in
deionized/distilled water for a minimum of 5 minutes to remove
excess antibiotics. Enough sterile glycerin USP solution is needed
to cover the graft(s). The basin is labeled as Rinse. The time of
exposure to the glycerin USP rinse solution is recorded on the
Tissue Processing Log Worksheet.
[0150] The fashioned graft(s) are then placed on sterile fine mesh
gauze, and the gauze is trimmed to just beyond the edges of the
graft. The width and length of the graft(s) is measured to the
nearest tenth of a centimeter. The graft(s) are assigned
identification numbers and this information is recorded on the
Tissue Processing Log Worksheet. The graft and gauze is then rolled
into a tube and graft material is then placed into glass, 120 ml
bottles, and the printed label is affixed with the unique numeric
designator. This step is repeated until all deposits are bottled.
The graft material is now ready for wrapping and freeze-drying or
dehydrating.
EXAMPLE 10
[0151] Processing Pericardium
[0152] A. Cleaning and Processing: The pericardial tissue is rinsed
of any blood or pericardial fluid in sterile water in the basin
labeled Rinse. The pericardium is then placed on a clean drape
towel. Using blunt dissection techniques, all of the fat and
extraneous soft tissue is removed from the graft material. The
graft is kept moist with sterile water to prevent desiccation
during processing. Any torn fibers are removed from the edges of
the graft material, and a graft rectangular in shape is created.
The graft(s) are then placed in a basin containing a 1:100 dilution
of Allowash Solution or other surfactant(s) for at least 15
minutes. The basin is labeled as Allowash.TM. Solution. The time of
exposure is recorded on the Tissue Processing Log Worksheet.
[0153] The graft(s) are placed into an empty basin labeled "Rinse".
The graft(s) are rinsed three time with copious amounts of sterile
water to remove any residual detergents. Any sterile water which
accumulates in the Rinse basin is discarded. The number of rinses
is recorded on the Tissue Processing Log Worksheet. The fashioned
graft(s) are then placed in the basin containing U.S.P. grade 70%
isopropyl alcohol containing 30% glycerin USP for 2-5 minutes. The
basin is labeled IPA/Glycerin. The time of exposure to the
alcohol/glycerin USP solution is recorded in the Tissue Processing
Log Worksheet.
[0154] The graft(s) are then placed into the basin containing the
antibiotic solution in 30% glycerin USP for at least 15 minutes.
The basin is labeled as Antibiotics/Glycerin USP. The exposure time
to the antibiotics/glycerin USP is recorded on the Tissue
Processing Log Worksheet. The graft(s) are then thoroughly soaked
by immersing each deposit into sterile 30% glycerin USP in
deionized/distilled water for a minimum of 5 minutes, preferably
from 10 to 15 minutes, to remove excess antibiotics. Enough sterile
glycerin USP-solution is needed to cover the graft(s). The basin is
labeled as Rinse. The time of exposure to the glycerin USP rinse
solution is recorded on the Tissue Processing Log Worksheet.
[0155] The fashioned graft(s) are then placed on sterile fine mesh
gauze, and the gauze is trimmed to just beyond the edges of the
graft. The width and length of the graft(s) is measured to the
nearest tenth of a centimeter. The graft(s) are assigned
identification numbers and this information is recorded on the
Tissue Processing Log Worksheet. The graft and gauze is then rolled
into a tube and graft material is then placed into glass, 120 ml
bottles, and the printed label is affixed with the unique numeric
designator. This step is repeated until all deposits are bottled.
The graft material is now wrapped and placed in a freeze dryer or
dehydrated.
[0156] All of the publications and patent applications cited herein
are hereby incorporated by reference into the present disclosure.
It will be appreciated by those skilled in the art that various
modifications can be made without departing from the essential
nature thereof. It is intended to encompass all such modifications
within the scope of the appended claims.
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