U.S. patent application number 11/126543 was filed with the patent office on 2005-10-06 for suture anchor.
Invention is credited to Bonutti, Peter M..
Application Number | 20050222620 11/126543 |
Document ID | / |
Family ID | 24510219 |
Filed Date | 2005-10-06 |
United States Patent
Application |
20050222620 |
Kind Code |
A1 |
Bonutti, Peter M. |
October 6, 2005 |
Suture anchor
Abstract
An improved suture anchor is formed from body tissue. The body
tissue is shaped to a desired configuration for the anchor and
defines a passage through the anchor. A suture is inserted into the
passage in the body tissue of the anchor. The anchor is then
positioned in a patient's body with a suture extending into the
passage in the anchor. The anchor may be formed of osseous body
tissue, hard compact bone, dense connective body tissue, or other
body tissue. The body tissue may be dried so that it absorbs fluid
and expands upon being inserted into a patient's body
Inventors: |
Bonutti, Peter M.;
(Effingham, IL) |
Correspondence
Address: |
PAUL D. BIANCO: FLEIT, KAIN, GIBBONS,
GUTMAN, BONGINI, & BIANCO P.L.
601 BRICKELL KEY DRIVE, SUITE 404
MIAMI
FL
33131
US
|
Family ID: |
24510219 |
Appl. No.: |
11/126543 |
Filed: |
May 11, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11126543 |
May 11, 2005 |
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09925551 |
Aug 9, 2001 |
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6899722 |
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09925551 |
Aug 9, 2001 |
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09344982 |
Jun 25, 1999 |
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6309405 |
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09344982 |
Jun 25, 1999 |
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08929628 |
Sep 15, 1997 |
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5989282 |
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08929628 |
Sep 15, 1997 |
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08626393 |
Mar 29, 1996 |
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5713921 |
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Current U.S.
Class: |
606/232 |
Current CPC
Class: |
A61B 2017/0414 20130101;
A61B 2017/0417 20130101; A61B 2017/00526 20130101; A61B 17/1637
20130101; A61B 2017/00933 20130101; A61B 2017/0409 20130101; A61B
17/0401 20130101 |
Class at
Publication: |
606/232 |
International
Class: |
A61B 017/04 |
Claims
What is claimed is:
1. A method of anchoring a suture in a body of a patient,
comprising: forming an anchor of body tissue including molding the
body tissue about an elongated member and removing the elongated
member from the molded body tissue to form an axial passage there
through; inserting a suture into the axial passage in the anchor;
and positioning the anchor in the body of the patient.
2. A method as set forth in claim 1, wherein molding the body
tissue about an elongated member including positioning the body
tissue in a mold defining a mold chamber, the elongated member
extending through the mold chamber.
3. A method as set forth in claim 1, wherein the mold chamber
defines a cylinder.
4. A method as set forth in claim 2, wherein forming an anchor of
body tissue includes forming the anchor of osseous body tissue.
5. A method as set forth in claim 1, wherein forming an anchor of
body tissue includes forming the anchor of dried body tissue.
6. A method as set forth in claim 5, wherein positioning the anchor
in the body of the patient includes positioning the anchor at a
location in the body of the patient where the anchor is exposed to
body fluid to enable the dried body tissue of the anchor to absorb
body fluid.
7. A method as set forth in claim 6, wherein the anchor expands as
it absorbs the body fluid.
8. A method as set forth in claim 1, wherein forming an anchor of
body tissue includes forming the anchor of body tissue which
includes collagen.
9. A method as set forth in claim 1, wherein forming an anchor of
body tissue includes forming the anchor of interarticular
fibrocartilage.
10. A method as set forth in claim 1, wherein forming an anchor of
body tissue includes forming the anchor from an allograft or
xenograft.
11. A method as set forth in claim 1, wherein forming an anchor of
body tissue includes forming the anchor of connective body
tissue.
12. A method as set forth in claim 11, wherein the connective body
tissue includes cartilage, tendons, or ligaments.
13. A method as set forth in claim 1, wherein forming an anchor of
body tissue includes forming the anchor from body tissue removed
from a donor.
14. A method as set forth in claim 13, wherein the donor is the
patient.
15. A method as set forth in claim 1, wherein positioning the
anchor in the body of the patient includes moving the anchor into
the body of the patient, and thereafter pivoting the anchor
relative to the body of the patient.
16. A method as set forth in claim 15 wherein pivoting the anchor
includes tensioning the suture to apply force to the anchor.
17. A method as set forth in claim 1, wherein the anchor formed of
body tissue includes first and second end portions and an outer
side surface extending between the first and second end portions,
wherein the passage axially extends through the first and second
end portions
18. A method as set forth in claim 17, wherein positioning the
anchor in the body of the patient includes inserting the first end
portion into the body of the patient and applying a force against
the second end portion of the anchor.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of application Ser. No.
09/925,551 filed Aug. 9, 2001. The aforementioned application Ser.
No. 09/925,551 is itself a division of application Ser. No.
09/344,982, filed Jun. 25, 1999, now U.S. Pat. No. 6,309,405. The
aforementioned application Ser. No. 09/344,982 is itself a division
of application Ser. No. 08/929,628, filed Sep. 15, 1997, now U.S.
Pat. No. 5,989,282. The aforementioned application Ser. No.
08/929,628 is itself a division of application Ser. No. 08/626,393,
filed Mar. 29, 1996, now U.S. Pat. No. 5,713,921. The benefit of
the earlier filing dates of the aforementioned applications is
hereby claimed.
FIELD OF THE INVENTION
[0002] The present invention relates to a new and improved suture
anchor and more specifically to a suture anchor which is formed of
body tissue.
BACKGROUND OF THE INVENTION
[0003] Anchors are commonly utilized to retain sutures in a
patient's body. The anchors have previously been formed of metal,
such as stainless steel or titanium. In addition, anchors have been
formed of biodegradable materials. While being generally
satisfactory, these known anchors have the drawback that they are
material which is not body tissue and are inserted into a patient's
body. It has previously been suggested to construct anchors in the
manner disclosed in U.S. Pat. Nos. 5,405,359; 5,403,348; 5,203,787;
5,046,513; and 5,041,129.
SUMMARY OF THE INVENTION
[0004] The present invention relates to a new and improved suture
anchor which is formed of body tissue. The body tissue is shaped to
the desired configuration of the anchor. The body tissue defines a
passage through the anchor. A suture is inserted into the passage
in the anchor. The anchor and the suture are inserted into a
patient's body.
[0005] The anchor may be formed of many different types of body
tissue, including osseous body tissue, bone, or dense connective
tissue. The body tissue may be dried so that when the anchor is
exposed to fluid in a patient's body, the anchor absorbs the fluid
and expands. The body tissue may be from the patient's body, from
another human, or from a non-human animal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The foregoing and other features of the invention will
become more apparent upon a consideration of the following
description taken in connection with the accompanying drawings,
wherein:
[0007] FIG. 1 is a schematic illustration depicting the manner in
which a thin elongated member is inserted into body tissue;
[0008] FIG. 2 is a schematic illustration, generally similar to
FIG. 1, illustrating the manner in which a cutting tool is moved
axially along the thin elongated member into the body tissue;
[0009] FIG. 3 is an enlarged schematic illustration of body tissue
formed with the thin elongated member and cutting tool of FIGS. 1
and 2;
[0010] FIG. 4 is a schematic illustration depicting the manner in
which an anchor formed of the body tissue of FIG. 3 is inserted
into a patient's body with a suture extending into the anchor;
[0011] FIG. 5 is a schematic illustration depicting the manner in
which the anchor of FIG. 4, formed of body tissue, is pivoted in a
patient's body;
[0012] FIG. 6 is a schematic illustration depicting the manner in
which the patient's body tissue is secured with a suture which
extends into the anchor formed of body tissue;
[0013] FIG. 7 is a sectional view of an anchor formed of dense
connective body tissue;
[0014] FIG. 8 is a schematic illustration depicting the manner in
which dense connective body tissue is shaped in a press;
[0015] FIG. 9 is a schematic illustration depicting the manner in
which a cutting tool is used to cut an anchor from the body tissue
shaped with the press of FIG. 8; and
[0016] FIG. 10 is a schematic illustration depicting the manner in
which a mold is used to shape body tissue to form an anchor.
DETAILED DESCRIPTION OF THE INVENTION
[0017] General Description
[0018] Suture anchors have previously been utilized to retain
sutures in either hard or soft tissue in a human patient's body.
The suture anchors have previously been formed of metal,
biodegradable materials, and other materials which do not naturally
occur in a patient's body. The insertion of materials other than
body tissue into a patient's body may be objectionable.
[0019] In accordance with a feature of the present invention,
sutures are retained in a patient's body by anchors formed of body
tissue. In one specific embodiment of the invention, the anchor is
formed of bone or osseous (bonelike) tissue. In another embodiment
of the invention, the anchor is formed of dense connective body
tissue. The dense connective body tissue may contain collagen. The
dense connective body tissue may be cartilage, tendon or ligament.
The dense connective body tissue may be interarticular
fibrocartilage which previously formed a meniscus in a joint.
Although it is believed that it may be preferred to use bone,
osseous tissue, or dense connective tissue to form the anchor,
other body tissue may be utilized if desired.
[0020] It is contemplated that the body tissue which is used to
form the anchor may be dried. When an anchor formed of dried body
tissue is inserted into a patient's body at a location where it is
exposed to the fluids in the patient's body, the anchor absorbs the
body fluid and expands. As the anchor expands, it presses against
the surrounding tissue in the patient's body and becomes firmly
interlocked with the surrounding tissue of the patient's body.
[0021] It is contemplated that the body tissue forming the anchor
may be dried in many different known ways. Specifically, the body
tissue may be dried by placing it in a press and applying pressure
against the body tissue to force fluid from the body tissue.
Alternatively, the body tissue may be freeze dried or dried by
exposure to a relatively warm dry environment. The dried body
tissue which forms the anchor may be bone, osseous tissue, dense
connective tissue, or other body tissue. For example, the dried
body tissue forming the anchor could be formed of dried skin or
other soft tissue and be used to retain a suture in soft body
tissue.
[0022] It is contemplated that the body tissue used to form the
anchor may be the patient's own body tissue (autograft). It is
believed that this has the advantage of minimizing the remote
possibility of infecting a patient with the material of the anchor.
However, the body tissue forming the anchor may be obtained from
another human patient (allograft) or from a non-human animal, such
as a bovine animal (xenograft).
[0023] It is contemplated that an anchor formed of body tissue in
accordance with the present invention may have many different
configurations. Thus, the anchor may have a polygonal configuration
or a generally spherical configuration. However, it is believed
that it may be preferred to form the anchor with a cylindrical
configuration and with a passage to receive a portion of a
suture.
[0024] When an anchor is to be formed, a thin elongated member may
be inserted into body tissue. The thin elongated member is used to
guide a cutting tool as it moves into the body tissue. The cutting
tool forms a cylindrical outer side surface of the anchor. The thin
elongated member forms a passage which extends through the anchor.
Although this method of forming the anchor may be preferred, it is
contemplated that other methods of forming the anchor could be
utilized if desired. For example, the body tissue may be shaped
with a press or molded to a desired configuration.
[0025] Anchor Formed of Bone or Osseous Body Tissue
[0026] Body tissue 12 is illustrated schematically in FIG. 1. The
body tissue 12 may be disposed within a human patient's body or may
be separate from the patient's body. The body tissue 12 may be the
patient's own body tissue or may be body tissue from another human
patient. Alternatively, the body tissue 12 may be from a non-human
animal, such as a bovine animal. Although the body tissue 12 has
been illustrated in FIG. 1 as having a polygonal configuration, the
body tissue 12 may have any desired configuration. When the body
tissue 12 is disposed within a patient's body, it is contemplated
that the body tissue will have a configuration corresponding to the
configuration of a naturally occurring portion of the patient's
body.
[0027] The body tissue 12 may be natural or artificial bone or
osseous body tissue. In the embodiment of the invention illustrated
in FIG. 1, the body tissue 12 is hard compact human bone of the
type which encloses soft cancellous bone. The bone forming the body
tissue 12 may be a bone in the body of the human patient, for
example, a portion of a femur of a patient. However, in FIG. 1, the
body tissue 12 is illustrated as being spaced from the patient's
body.
[0028] When a suture anchor is to be formed from the body tissue
12, a thin elongated metal member 14 is inserted into the hard
compact human bone. The thin elongated member 14 may be a K-wire or
similar article. The thin elongated member 14 is inserted into the
hard bony body tissue 12 by rotating the thin elongated member
about its longitudinal central axis 16 and pressing a leading end
of the thin elongated member against the body tissue.
[0029] The leading end of the thin elongated member 14 may be
pointed or may have a flat circular configuration. If desired, the
leading end of the thin elongated member 14 may be provided with a
cutting edge, similar to a cutting edge used on a drill. Although
it is preferred to rotate the thin elongated member 14 as it is
inserted into the hard compact bone 12, with other body tissue, the
thin elongated member may be inserted without being rotated about
its central axis.
[0030] In the illustrated embodiment of the thin elongated member
14, the thin elongated member has a cylindrical outer side surface
with a diameter which corresponds to the desired diameter of a
passage to be formed in a suture anchor formed of the body tissue
12. In the procedure illustrated in FIG. 1, the thin elongated
member 14 is rotated about the axis 16 and pushed completely
through the piece of body tissue 12. However, if desired, the thin
elongated member 14 could be moved only part way through the body
tissue 12. For example, when the body tissue 12 is disposed within
a patient's body, it is contemplated that the thin elongated member
14 may not be inserted completely through the portion of the
patient's body formed by the body tissue.
[0031] Once the thin elongated member 14 has been inserted into the
body tissue 12, in the manner illustrated in FIG. 1, a rotating
metal cutting tool 20 is moved axially along the thin elongated
member 14 into the body tissue. The cutting tool 20 has a leading
or cutting portion 22 (FIG. 2) and a trailing or guiding portion
24. The cutting portion 22 of the cutting tool 20 has a tubular
cylindrical configuration. Thus, the leading or cutting portion 22
of the cutting tool 20 has a cylindrical outer side surface 28 and
a cylindrical inner side surface 30. The cutting portion 22 of the
cutting tool 20 has a leading end portion which may form a portion
of a cone or which may have cutting teeth to promote a cutting
action as the cutting tool is rotated and moved axially along the
thin elongated member 14.
[0032] The trailing or guiding portion 24 of the cutting tool 20
has a cylindrical outer side surface 34. The outer side surface 34
forms a continuation of the cylindrical outer side surface 28 of
the leading or cutting portion 22 of the cutting tool. In addition,
the trailing or guiding portion 24 of the cutting tool 20 has a
cylindrical inner side surface 36. The inner side surface 36
engages and is freely movable relative to the cylindrical outer
side surface of the thin elongated member 14.
[0033] The cylindrical inner side surface 36 of the guiding portion
24 of the cutting tool 20 engages the cylindrical outer side
surface of the thin elongated member 14. This enables the guiding
portion 24 to maintain the leading or cutting portion 22 of the
rotating cutting tool 20 in a coaxial relationship with the thin
elongated member 14. Although it is preferred to rotate the cutting
tool 20 as it is moved into the hard compact bone 12, with other
body tissue, the cutting tool may be inserted without being rotated
about its central axis 16.
[0034] After the thin elongated member 14 has been inserted into
the body tissue 12, in the manner illustrated in FIG. 1, the
cutting tool 20 is moved into telescopic engagement with the thin
elongated member. The cutting tool 20 is rotated about the central
axis 16 of the thin elongated member by an electric or pneumatic
motor or similar device. As the cutting tool 20 is rotated about
the longitudinal central axis 16 of the thin elongated member 14,
the cutting tool is moved axially along the thin elongated member
into engagement with the body tissue 12.
[0035] As the leading or cutting portion 22 of the rotating cutting
tool 20 moves into engagement with the body tissue 12, the cutting
portion cuts a very thin annular groove around the thin elongated
member 14 in a coaxial relationship with the thin elongated member.
As the cutting tool 20 moves axially into the body tissue 12, a
cylindrical core 40 of body tissue is cut from the block of bone.
The cylindrical core 40 of body tissue is disposed within the
tubular leading end portion 22 of the cutting tool 20. Once a core
40 of a desired axially extent has been cut in the body tissue 12,
the cutting tool 20 is moved upward (as viewed in FIG. 2) along the
thin elongated member and out of engagement with the body tissue
12. The core 40 is then removed from the remaining body tissue
12.
[0036] The core 40 (FIG. 3) has a tubular cylindrical
configuration. The cylindrical core 40 has a tubular wall 44 formed
of the body tissue 12. The tubular wall 44 has a cylindrical outer
side surface 46 which is coaxial with a cylindrical inner side
surface 48. The cylindrical outer side surface 46 has a diameter
corresponding to the desired outside diameter of a suture anchor.
The cylindrical outer side surface 46 of the tubular side wall 44
was formed by and has the same diameter as the inner side surface
30 of the cutting portion 22 of the cutting tool 20.
[0037] The cylindrical inner side surface 48 of the core 40 has a
diameter corresponding to the diameter of the cylindrical outer
side surface of the thin elongated member 14. The cylindrical inner
side surface 48 forms a passage 50 which extends axially through
the cylindrical core 40. The tubular side wall 44 of the
cylindrical core 40 is formed as one piece of the body tissue
12.
[0038] The core 40 has an axial extent which is greater than the
desired axial extent of a suture anchor. Therefore, the core 40 is
cut, along a line indicated at 54 in FIG. 3, to form a suture
anchor 58 with a desired axial extent. Although the core 40 may be
cut or ground to form an anchor 58 with any one of many different
axially tapering or flaring configurations, such as those disclosed
in U.S. Pat. No. 5,403,348, it is believed that it may be preferred
to form the anchor 58 with a cylindrical configuration.
[0039] Although it is contemplated that the tubular cylindrical
suture anchor 58 could be of many different sizes, it is believed
that the suture anchor may preferably have a length or axial extent
of between 2 and 4 millimeters. The cylindrical outer side surface
46 of the suture anchor 58 may have a diameter of between 1 and 2
millimeters. The cylindrical inner side surface 48 of the passage
50 in the suture anchor 58 may have a diameter of 1/2 to 1
millimeters. Of course, the suture anchor 58 could be formed with
different dimensions if desired.
[0040] Since the volume of body tissue which is required to form
the suture anchor 58 is relatively small, the bone which forms the
suture anchor 58 can be removed from a patient's own body with
minimal detrimental effect to the patient. Thus, the thin elongated
member 14 may be, inserted into a bone in a patient's body. The
cutting tool 20 would then be used to cut the bone in the patient's
body. Of course, if desired, the body tissue for the suture anchor
58 could be obtained from another source, such as another human or
from a non-human animal.
[0041] Once the suture anchor 58 has been formed from the body
tissue 12, a suture 62 (FIG. 4) is inserted into the passage 50 in
the suture anchor 58. The suture 62 includes a portion or leg 64
which extends away from an annular end surface 66 of the anchor 58.
In addition, the suture 62 has a second portion or leg 68 which
extends across an annular end surface 70 of the anchor 58. The leg
68 of the suture 62 extends along the cylindrical outer side
surface 46 of the anchor 58 to a location adjacent to and spaced
from the leg portion 64 of the suture 62. A relatively short
portion 74 of the suture 62 interconnects the leg portions 64 and
68 and is disposed in the passage 50 in the suture anchor 58.
[0042] An inserter assembly 80 is used to position the suture
anchor 58 and a portion of the suture 62 in a patient's body tissue
84. The inserter assembly 80 includes a cylindrical tubular outer
sleeve 86 having a central passage 88 in which the anchor 58 is
disposed. The inserter 80 also includes a tubular inner sleeve 92
which is telescopically received in the outer sleeve 86. The
tubular inner sleeve 92 has a bevelled leading end portion 94 which
engages the trailing end surface 66 of the anchor 58.
[0043] The leg or portion 64 of the suture 62 extends through a
cylindrical passage 96 in the inner sleeve 92. The leg or portion
68 of the suture 62 extends through the central passage 88 in the
outer sleeve 86 along a path which extends between the inner and
outer sleeves. However, if desired, one of the legs or portions 64
or 68 of the suture could be omitted. If this was done, the suture
62 could be tied off at one end of the anchor 58.
[0044] It is contemplated that the anchor 58 may be inserted into a
human patient's body at many different locations. The anchor 58 may
be inserted into either hard or soft tissue. In the situation
illustrated schematically in FIG. 4, the anchor 58 is being
inserted into bone tissue 84 in a patient's body. A recess 100 is
formed in the bone tissue 84 of the human patient's body by
drilling or other methods. The recess 100 extends through the hard
compact outer layer 102 of the patient's bone tissue 84 into the
relatively porous inner or cancellous tissue 104. The illustrated
anchor 58 is formed of the same bone as the hard outer layer
102.
[0045] To insert the anchor 58 in the patient's body tissue 84, the
inner sleeve 92 is moved axially downward (as viewed in FIG. 4) to
apply force against the trailing annular end surface 66 of the
anchor 58. Once the anchor 58 has been pushed into the recess 100
by axial movement of the inner sleeve 92 relative to the outer
sleeve 86, the leg 68 of the suture 62 is tensioned to apply force
against the leading annular end surface 70 of the anchor 58. At the
same time, the bevelled leading end 94 of the inner sleeve 92 is
pressed against the trailing end surface 66 of the anchor.
[0046] This results in the application of a counterclockwise (as
viewed in FIGS. 4 and 5) torque to the anchor 58. This torque
causes the anchor to pivot through the orientation shown in FIG. 5
toward the orientation shown in FIG. 6. Once the anchor has been
pivoted to the orientation shown in FIG. 6, by tensioning the
suture 62 and applying force against the anchor with the leading
end portion 94 of the inner sleeve 92, the anchor 58 engages the
hard compact outer layer 102 of the patient's bone tissue 84 to
hold the anchor in the recess 100.
[0047] The suture 68 can then be used to secure body tissue 110 in
place. The body tissue 110 may be soft tissue, or a ligament, or a
tendon, or other body tissue. If desired, the suture 62 may be used
to secure an implant or splint in place relative to the patient's
body tissue 84.
[0048] One specific known inserter assembly 80 and method of
inserting a suture anchor 58 into a patient's body tissue has been
illustrated in FIGS. 4-6. This specific inserter assembly and the
method of inserting the anchor 58 are the same as is disclosed in
U.S. Pat. No. 5,403,348 issued Apr. 4, 1995 and entitled "Suture
Anchor". However, it is contemplated that many different known
types of inserter assemblies could be utilized to install the
suture anchor with many different methods in a patient's body
tissue. For example, the inserter assembly and method disclosed in
U.S. Pat. No. 5,464,426 issued Nov. 7, 1995 and entitled "Method of
Closing Discontinuity in Tissue" could be utilized if desired. Of
course, other known apparatus and methods could also be utilized if
desired.
[0049] In the embodiment of the invention illustrated in FIGS. 1-6,
the anchor 58 is formed of hard compact outer bone. However, it is
contemplated that the anchor 58 could be formed of osseous body
tissue other than hard compact bone. The osseous body tissue could
be obtained from the patient or from other sources.
[0050] Anchor Formed of Dense Connective Body Tissue
[0051] In the embodiment of the invention illustrated in FIGS. 1-6,
the anchor 58 is formed of osseous tissue. In the embodiment of the
invention illustrated in FIGS. 7-9, an anchor is formed of dense
connective body tissue. Since the embodiment of the invention
illustrated in FIGS. 7-9 is generally similar to the embodiment of
the invention illustrated in FIGS. 1-6, similar numerals will be
utilized to identify similar components, the suffix letter "a"
being associated with the components of FIGS. 7-9 to avoid
confusion.
[0052] A suture anchor 58a formed of dense connective body tissue
is illustrated in FIG. 7. The suture anchor 58a has the same
configuration as the suture anchor 58 of FIGS. 3 and 4. The suture
anchor 58a cooperates with a suture in the same manner as in which
the suture anchor 58 cooperates with the suture 62 (FIGS. 4-6).
[0053] The suture anchor 58a (FIG. 7) has a cylindrical tubular
side wall 44a formed of dense connective body tissue. The tubular
side wall 44a has a cylindrical outer side surface 46a and a
cylindrical inner side surface 48a which extend between axially
opposite annular end surfaces 66a and 70a of the suture anchor 58a.
The cylindrical inner side surface 48a is disposed in a coaxial
relationship with the cylindrical outer side surface 46a and
defines a passage 50a which extends axially through the suture
anchor 58a.
[0054] Although the suture anchor 58a has a tubular cylindrical
configuration, it is contemplated that the suture anchor 58a could
have a different configuration if desired. For example, the suture
anchor 58a could have a polygonal configuration. If desired, the
suture anchor 58a could be formed with a spherical configuration.
The suture anchor 58a may have an axially tapering or flaring
configuration, similar to the configurations of anchors disclosed
in the aforementioned U.S. Pat. No. 5,403,348.
[0055] In accordance with a feature of this embodiment of the
invention, the suture anchor 58a is formed of dense connective body
tissue 120. The dense connective body tissue contains collagen. It
is contemplated that the dense connective body tissue 120 may be
formed from ligaments or tendon. It is also contemplated that the
dense connective body tissue 120 may be formed from cartilage, such
as interarticular fibrocartilage which forms a meniscus in a joint.
It should be understood that dense connective body tissue other
than the specific examples set forth above may be utilized if
desired.
[0056] The dense connective body tissue 120 forming the suture
anchor 58a may be removed from a patient's own body. Alternatively,
the dense connective body tissue may be obtained from a human other
than the patient into which the suture anchor 58a is to be
inserted. If desired, the dense connective body tissue 120 could be
obtained from a non-human animal, such as a bovine animal. However,
it is believed that it may be preferred to use a patient's own
dense connective body tissue to form the suture anchor 58a in order
to minimize any possibility of infection. If the dense connective
body tissue is obtained from a source other than a patient's own
body, it may be desired to sterilize the dense connective body
tissue using ethylene oxide gas or other sterilizing agents.
[0057] Although the dense connective body tissue 120 could be
shaped in many different ways, it is preferred to place the dense
connective body tissue in a press 122 (FIG. 8). The press 122 has
an upper platen 124 which presses the dense connective body tissue
120 against a lower platen 126 to form a flat sheet 130 of dense
connective body tissue. The flat sheet 130 has a thickness, as
measured perpendicular to parallel flat upper and lower major side
surfaces 134 and 136 (FIG. 9) of the flat sheet, which is equal to
the desired axial extent of the suture anchor 58a (FIG. 7). Thus,
the thickness of the flat sheet 130 is equal to the distance
between opposite annular end surfaces 66a and 70a (FIG. 7) of the
suture anchor 58a.
[0058] A cutting tool 20a (FIG. 9) is used to cut the sheet 130 to
form the suture anchor 58a. The cutting tool 130 includes a thin
elongated member 14a having a cylindrical outer side surface with a
diameter which corresponds to the diameter of the passage 50a in
the suture anchor 58a (FIG. 7). In the illustrated embodiment of
the cutting tool 20a, a leading end portion 142 of the thin
elongated member 14a has a sharp conical configuration. However, if
desired, the leading end portion 142 could have a flat circular
configuration. Alternatively, the leading end portion 142 of the
thin elongated member 14a could have a thin hollow tubular
configuration.
[0059] The cutting tool 20a has a leading or cutting portion 22a.
The leading or cutting portion 22a has a cylindrical outer side
surface 28a and a cylindrical inner side surface 30a. The cutting
portion 22a of the cutting tool 20a has a sharp leading end portion
144 which is formed as a portion of a right circular cone having a
central axis which is coincident with the central axis of the
cutting tool 20a and with the central axis of the thin elongated
member 14a. A trailing portion 24a of the cutting tool 20a is
gripped by a drive device (not shown).
[0060] When the suture anchor 58a is to be formed from the sheet
130 of dense connective body tissue 120, the drive device moves the
cutting tool 20a straight downward (as viewed in FIG. 9) without
rotating the cutting tool. As the cutting tool 20a moves downward,
the thin elongated member 14a is inserted into and pierces the
sheet 130 of dense connective body tissue 120. Immediately after
the leading end portion 142 of the thin elongated member 14a enters
the sheet 130 of dense connective body tissue 120, the leading end
portion 144 of the cutting portion 22a engages the sheet 130 of
dense connective body tissue. Continued downward (as viewed in FIG.
9) movement of the cutting tool 20a results in the cutting portion
22a of the cutting tool cutting the sheet 130 of dense connective
body tissue with a cookie cutter type action.
[0061] This results in a cylindrical opening being formed in the
sheet 130 and in a body of dense connective body tissue 120 being
disposed in the cutting tool 20a. The body of dense connective body
tissue is removed from the cutting tool 20a with a suitable ejector
(not shown). The body of dense connective body tissue 120 which is
ejected from the cutting tool 20a will have a configuration
corresponding to the configuration of the suture anchor 58a. It
should be noted that the cutting tool 20a is reciprocated with a
linear cutting and return stroke and is not rotated about its
central axis as is the cutting tool 20 of FIG. 2.
[0062] If desired, the cutting tool 20a and thin elongated member
14a could be rotated together about their common central axis as
they are moved into the body tissue 120. This would result in the
same type of cutting action as is obtained with the separate thin
elongated member 14 and cutting tool 20 of FIGS. 1 and 2. However,
the rotating thin elongated member 14a and cutting tool 20a would
cut the body tissue simultaneously rather than sequentially as in
FIGS. 1 and 2.
[0063] It should be understood that a separate thin elongated
member, corresponding to the thin elongated member 14 of FIGS. 1
and 2, and a rotatable cutting tool, corresponding to the cutting
tool 20 could be utilized to cut the dense connective body tissue.
If desired, the dense connective body tissue could have a
configuration other than the configuration of the sheet 130. Thus,
a relatively large block or piece of dense connective body tissue
could be provided. Alternatively, the dense connective body tissue
of the anchor 58a could be obtained directly from the patient's own
body with the cutting tool 20a.
[0064] For example, the thin elongated member 14 could be inserted
axially into the dense connective body tissue in the manner
illustrated in FIG. 1 for the body tissue 12. The thin elongated
member could be inserted into the dense connective body tissue
while the thin elongated member is being rotated and pressed
against the dense connective body tissue in the same manner as
described in conjunction with the body tissue 12 of FIG. 1. The
rotating cutting tool 20 will then cut a relatively long
cylindrical core of dense connective body tissue. Once the core of
dense connective body tissue has been removed from the cutting tool
20 and the thin elongated member 14, the cylindrical core of dense
connective body tissue would be cut to a length corresponding to
the desired length of the suture anchor 58a.
[0065] It is also contemplated that a suitable press could be
utilized to shape the dense connective body tissue into the
cylindrical configuration of the anchor 58a. Thus, a press having a
construction similar to the construction disclosed in U.S. Pat. No.
5,329,846 issued Jul. 19, 1994 and entitled "Tissue Press and
System" could be utilized to form the dense connective body tissue
to a cylindrical configuration. If desired, the body tissue could
be shaped around a thin elongated member which is subsequently
withdrawn to form the passage 50a. Alternatively, the thin
elongated member could be inserted into a cylindrical piece of
dense connective body tissue to form the passage 50a after the body
tissue has been removed from the press or while the body tissue is
still in the press.
[0066] Once the suture anchor 58a has been formed, a suture is
inserted into the passage 50a and the suture anchor is inserted
into the body of a patient. The suture anchor 58a may be inserted
to the body of a patient using an inserter assembly having the same
construction as the inserter assembly 80 of FIGS. 4 and 5. Once the
suture anchor 58a has been pushed into a patient's body, the suture
is tensioned and force is applied against the trailing end of the
suture anchor by the inner sleeve of the inserter to pivot the
suture anchor in the manner illustrated schematically in FIG. 5. Of
course, the suture anchor 58a may be inserted into either hard or
soft body tissue in a manner which is different than the manner
illustrated schematically in FIGS. 4 and 5 using an inserter
assembly having a different construction than the inserter assembly
80.
[0067] Molded Suture Anchor
[0068] In the embodiments of the invention illustrated in FIGS.
1-9, the suture anchors 58 and 58a were formed by cutting and/or
pressing body tissue. In the embodiment of the invention
illustrated in FIG. 10, the suture anchor is formed by molding body
tissue. Since the embodiment of the invention illustrated in FIG.
10 is generally similar to the embodiments of the invention
illustrated in FIGS. 1-9, similar numerals will be utilized to
designate similar components, the suffix letter "b" being
associated with the numerals of FIG. 10 to avoid confusion.
[0069] When a suture anchor 58b is to be formed, particles of body
tissue, such as natural or artificial osseous body tissue, is
positioned in a mold 150. The mold 150 includes upper and lower
mold sections 152 and 154 which cooperate to define a cylindrical
mold chamber 156. The cylindrical mold chamber 156 has a length
corresponding to the desired axial extent of the suture anchor 58b.
The mold chamber 156 has a diameter which corresponds to the
desired diameter of the cylindrical outer side surface of the
suture anchor 58b.
[0070] A cylindrical thin elongated member or core 160 extends
axially through the mold chamber 156. An end plate 164 closes one
end of the mold chamber 156 and supports one end of the core 160. A
second end plate (not shown) closes the opposite end of the mold
chamber 156 and supports the opposite end of the core 160.
[0071] Particles of bone and a suitable binder are conducted into
the mold chamber. It is believed that it may be preferred to use
fibrin as the binder. The natural or artificial bone particles are
uniformly coated with the fibrin and completely fill the mold
chamber 156. The fibrin is solidified around and interconnects the
particles of body tissue to form the suture anchor 58b. It is
contemplated that pressure may be applied against the mixture of
binder and particles of body tissue in the mold 150 to compact the
mixture.
[0072] Suture Anchor Formed of Dried Body Tissue
[0073] Regardless of which of the various body tissues and methods
are utilized to form a suture anchor, it is contemplated that the
body tissue may be dried. When a suture anchor formed of dried
natural or artificial body tissue is inserted into a patient's
body, the suture anchor is exposed to the fluid in the patient's
body. The dried tissue of the suture anchor will absorb the fluid
in the patient's body.
[0074] As the dried suture anchor absorbs the fluids in the
patient's body, the suture anchor expands. As the suture anchor
expands, it presses against the surrounding tissue of the patient's
body and interlocks the suture anchor and the patient's body.
[0075] The suture anchor of dried body tissue can be inserted into
an opening in a patient's body in the manner illustrated
schematically for the suture anchor 58 in FIGS. 4 and 5. The suture
anchor of dried body tissue is inserted into the recess 100 and is
pivoted in the same manner as previously explained in conjunction
with the embodiment of the invention illustrated in FIGS. 4 and 5.
Once a suture anchor has been pivoted relative to the patient's
body from the orientation shown in FIG. 4 through the orientation
shown in FIG. 5 to the orientation shown in FIG. 6, the suture
anchor absorbs body fluids and expands to more completely fill the
recess 100.
[0076] It is contemplated that the suture anchor may be formed of
many different types of dried body tissue. Thus, the suture anchor
may be formed of dried osseous or bony body tissue. Alternatively,
the suture anchor may be formed of dried dense connective body
tissue, such as cartilage or tendon tissue. Although hard compact
bone tissue may be dried, there will be relatively little expansion
of the hard compact bone tissue when it is inserted into the
patient's body.
[0077] When a suture anchor is formed of dried body tissue, the
expansion or swelling of the suture anchor can be used to retain
the suture anchor at a location where it would not be retained
without expanding or swelling. Thus, a suture anchor formed of
dried skin or other soft tissue may be inserted beneath the skin-of
the patient. The dried skin or other soft tissue forming the suture
anchor will immediately begin to absorb the patient's body fluid
(blood). As this occurs, the suture anchor will expand. Expansion
of the suture anchor beneath the skin of the patient will prevent
the suture anchor from being pulled back through the opening
through which it was inserted beneath the skin of the patient.
[0078] Anchors formed of dried soft body tissue may be used at many
different locations in a patient's body. For example, suture
anchors formed of dried soft body tissue may be used in association
with internal organs. The dried soft body tissue forming a suture
anchor may be obtained from any one of many different sources. For
example, body tissue may be obtained from inside a human other than
the patient or from inside a non-human animal. This body tissue
would be sterilized and dried before being formed into a suture
anchor.
[0079] It is contemplated that the body tissue from which a suture
anchor is to be formed may be dried in many different ways. Thus,
the body tissue may be freeze dried. When a suture anchor is to be
formed, a thin elongated member, corresponding to the thin
elongated member 14 of FIG. 1, is inserted into the freeze dried
body tissue. The cutting tool 20 is then rotated and moved axially
along the thin elongated member to cut the freeze dried body tissue
in the same manner illustrated schematically in FIG. 2.
[0080] Rather than freeze drying the body tissue, the body tissue
could be dried by applying pressure against the body tissue and
forcing fluid to flow from the body tissue. Thus, a press, similar
to a press disclosed in U.S. Pat. No. 5,329,846 issued Jul. 19,
1994 and entitled "Tissue Press and System" may be utilized to
apply pressure against body tissue and force fluid from the body
tissue. When the body tissue is dried in this manner, the body
tissue may be compressed to a cylindrical configuration with an
outside diameter which corresponds to the outside diameter of a
suture anchor.
[0081] A passage may be formed in the compressed and dried body
tissue either before or after it is removed from the press. When
the body tissue has been removed from the press, it can be further
dried by being exposed to a warm dry environment. Alternatively,
the body tissue may be dried without pressing, by exposing the body
tissue to a warm dry environment for a sufficient length of time to
result in evaporation of the fluid from the body tissue.
[0082] Conclusion
[0083] The present invention relates to a new and improved suture
anchor 58 which is formed of body tissue. The body tissue is shaped
to the desired configuration of the anchor 58. The body tissue
defines a passage 50 through the anchor 58. A suture 62 is inserted
into the passage 50 in the anchor 58. The anchor 58 and the suture
62 are inserted into a patient's body.
[0084] The anchor 58 may be formed of many different types of body
tissue, including osseous body tissue, bone or dense connective
tissue. The body tissue may be dried so that when the anchor 58 is
exposed to fluid in a patient's body, the anchor absorbs the fluid
and expands. The body tissue may be from the patient's own body,
from another human, or from a non-human animal.
* * * * *