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| United States Patent Application |
20030167072
|
| Kind Code
|
A1
|
|
Oberlander, Michael A.
|
September 4, 2003
|
Multi-anchor suture
Abstract
A multi-anchor suture is provided which comprises at least two anchors and
at least one suture attached to each anchor. The multiple anchors are
inserted into a patient's bone and the suture connecting the anchors
facilitates reattachment of soft tissue to the bone. Also provided is a
method of attaching soft tissue to bone using the inventive multi-anchor
suture.
| Inventors: |
Oberlander, Michael A.; (Alamo, CA)
|
| Correspondence Address:
|
David L. Schwartz
Wallenstein & Wagner, Ltd.
53rd Floor
311 South Wacker Drive
Chicago
IL
60606-6630
US
|
| Serial No.:
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385037 |
| Series Code:
|
10
|
| Filed:
|
March 10, 2003 |
| Current U.S. Class: |
606/232; 606/304; 606/329; 606/75; 606/916 |
| Class at Publication: |
606/232; 606/72; 606/73; 606/75 |
| International Class: |
A61B 017/04; A61B 017/58 |
Claims
We claim:
1. A device for attaching soft tissue to bone during arthroscopic surgery
comprising: two anchors that are capable of being at least partially
inserted into a bone, wherein each anchor has a region adapted to reduce
the possibility that the anchor will disengage from the bone; and a
knotless suture attached to each anchor.
2. The device of claim 1 wherein the region adapted to reduce the
possibility that the anchor will disengage from the bone comprises barbs.
3. The device of claim 2 wherein the suture is attached to at least one
barb.
4. The device of claim 2 wherein the barbs bend slightly during insertion
of the anchor into the bone.
5. The device of claim 1 wherein the region adapted to reduce the
possibility that the anchor will disengage from the bone comprises
threads.
6. The device of claim 1 wherein the anchors each have a length and the
suture has a length, and wherein the length of the suture is less than
the length of at least one anchor.
7. The device of claim 1 wherein the anchors are relatively firmly
embedded in the bone.
8. The device of claim 1 wherein the suture and both anchors are intregal.
9. The device of claim 1 wherein at least one anchor is non-cannulated.
10. The device of claim 1 wherein the anchors are cannulated.
11. The device of claim 1 wherein the anchors are held in place during
initial insertion into the bone by guide wires.
12. The device of claim 1 wherein the suture is attached to each anchor at
a single position on each anchor.
13. The device of claim 1 wherein the two anchors are substantially
identical.
14. A method for attaching soft tissue to bone during arthoscopic surgery
comprising: inserting at least two anchors partially into a bone; and
connecting the anchors with a knotless suture to maintain a soft tissue
adjacent to the bone.
15. The method of claim 14 comprising the further step of: applying force
to the anchors to insert the anchors into the bone at least approximately
5-6 millimeters.
16. The method of claim 14 comprising the further step of: applying force
to the anchors at least until the suture is taut.
17. The method of claim 14 wherein the anchors are space apart in the bone
approximately 5 millimeters.
18. The method of claim 14 wherein the anchors are cannulated.
19. The method of claim 14 wherein at least one anchor is inserted into
the soft tissue.
20. A device for re-attaching soft tissue to bone comprising: two anchors
for insertion into a tissue and a bone; and a suture which is
eccentrically attached to each anchor without the use of a knot.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Provisional Application
Serial No. 60/151,423, filed Aug. 25, 1999. This application is a
continuation of co-pending prior U.S. application Ser. No. 09/645,671,
filed Aug. 24, 2000.
FIELD OF INVENTION
[0002] The present invention generally relates to the field of medical
devices and procedures. More specifically, the invention relates to
devices and methods for the re-attachment of soft tissue to bone.
BACKGROUND OF THE INVENTION
[0003] Re-attachment of soft tissue to bone is often required in surgery.
During athletic endeavors, work, falls, or repetitive use and aging, a
ligament or tendon may be pathologically avulsed or torn from its normal
insertion site. Soft tissue to bone re-attachment is then needed to
return to normal or near normal function to the limb or joint. Such
re-attachment may be necessary anywhere within the body, including, by
way of example but not by way of limitation, in the wrist, ankle, knee,
or shoulder. Re-attachment is considered important for several reasons.
First, it helps ensure proper healing. When a ligament has been torn away
from its normal position of attachment to bone it may become bathed in
synovial fluid, which is a poor healing environment. Second, even if the
ligament does heal, it may heal in a stretched out or elongated position,
possibly leading to residual joint laxity or dysfunction. Surgical repair
may thereby become necessary to return proper structure and function to
the joint. The present invention relates to the fixation of soft tissue
to bone at its proper location and is suitable for use in many common
surgical procedures including, by way of example but not limitation,
rotator cuff repair, bankart repair, ligament avulsions from bone (knee,
ankle, shoulder, wrist) and many others known to those of skill in the
art. While the invention is suitable for use in open surgery, it is
particularly useful for arthroscopic surgery.
[0004] The present invention is more fully described below. Many
publications are cited herein and the entire disclosure of each such
cited reference is hereby incorporated by reference in its entirety, and
should be considered a part of this disclosure as if set forth in its
entirety at the point of reference.
[0005] Several approaches for attaching soft tissue to bone exist in the
art. Each suffers disadvantages.
[0006] One approach requires transossous suture tunnels. The use of such
tunnels is described more fully in Shoulder Reconstruction by Charles S.
Neer II (W. B. Saunders Co. 1990). Although appropriate for some cases,
the use of bone tunnels can be difficult and generally requires large
open incisions.
[0007] Another approach, which is especially useful in closed,
arthroscopic or endoscopic settings, involves the use of suture anchors
that allow quick fixation without the need for extensive exposure. A
common problem among many such anchor systems is that they require knot
tying of the attached sutures after the suture anchors are inserted into
the bone and the sutures placed through the soft tissue.
[0008] One example of a suture anchor assembly is set forth in U.S. Pat.
No. 5,441,502, which describes an anchor assembly having a pre-threaded
suture positioned at the posterior of the anchor. After the suture anchor
is properly deployed in the bone, the associated suture extends upwardly
through the soft tissue. The free ends of the sutures are then tied to
secure the soft tissue to the bone.
[0009] An important limitation of this prior art is the requirement for
knot tying. Knot tying itself is time consuming and technically
demanding, especially in an arthroscopic environment, where surgery is
done in small spaces through small incisions. In addition, knot slippage
or suture breakage during knot tying could lead to unsecured attachment
of the soft tissue to bone, potentially adversely affecting the healing
process.
[0010] Some non-suture anchor systems have been described, such as in U.S.
Pat. Nos. 5,840,078, 5,013,316, and 4,532,926. However, fixation with
these devices may not be as secure as that achieved with sutures. In
addition, non-suture anchors offer fewer points of fixation, typically
providing only one point of soft tissue to device fixation per device,
and one point of device to bone fixation per device.
[0011] Staple-like devices have been used surgically to eliminate the need
for suturing outside of the soft-tissue to bone context. U.S. Pat. Nos.
4,994,073 and 5,089,009 describe surgical skin fasteners that eliminate
the need for suturing when joining adjacent portions of soft tissue. The
fastener comprises a backspan and two prongs depending therefrom. The
skin fasteners are mostly useful for joining two edges of body tissue
together or for joining layers of tissue both laterally or laminarly as
required in skin grafting. Other surgical tacks made of bioabsorbable
material such as the bankart tack (Bionix) and the Suretek (Acufex) leave
hard polylactic or polyglycolic acid portions of the tack exposed. These
exposed hard polymers pose potential injury to the articular cartilage or
if broken off, may result in loose bodies, which may cause further joint
deterioration or mechanical symptoms.
[0012] Staple-like devices have also been used for attaching bone to bone.
U.S. Pat. No. 4,994,063 describes a bone staple with two feet and a
central web portion made of rigid material. Portions of bone on opposite
sides of a fracture are compressed toward each other by inserting the two
feet of the staple into each bone portion and crimping the central web
portion of the staple.
[0013] Staple-like devices having large rigid bodies have also been used
to attach artificial soft tissue to bone. U.S. Pat. No. 4,793,335
describes a bone implant composed of a deformable metal plate and a pair
of anchor pins attached to and extending from the metal plate. The staple
described therein is used to hold a tendon or ligament over a relatively
large area. These staples are not suitable for intra-articular usage
because they tend to loosen in time with cyclical loading of the tissues
and may become a loose object within the joint, causing further injury.
SUMMARY OF THE INVENTION
[0014] The invention relates to devices and methods for re-attaching soft
tissue to bone. The invention is based in part on the discovery of an
assembly comprising at least one suture joining multiple cannulated or
non-cannulated anchors. This invention also relates to cannulated
instruments to apply the suture-anchor assembly. Although the invention
includes within its scope assemblies comprising multiple sutures or
multiple anchors, in one embodiment a single suture is joined by two
cannulated anchors. In this embodiment, the two cannulated anchors joined
by suture can be easily and precisely inserted over guide wires at an
optimal point of fixation through one larger arthroscopic cannula,
thereby providing a knotless mechanism for attachment of soft tissue to
bone having two points of fixation for a single suture. The invention
thereby avoids the problems of the prior art associated with knot tying
while at the same time providing improved structural and performance
characteristics such as increased number of points of fixation per suture
and facilitated arthroscopic insertion and placement. The invention also
minimizes the risk of a portion of the device breaking off and becoming
loose within the joint.
[0015] As used herein, the word "re-attach," and all forms thereof such as
"re-attached," "re-attachment," and "re-attaching," is intended to
include not only its ordinary meaning but also the concept of "attach."
Therefore, the term will be understood to properly describe any situation
in which components are being attached, regardless of whether they had
been attached previously.
[0016] In accordance with one aspect of the present invention, a system
for attaching soft tissue to bone is provided. The system is composed of
one integrated assembly. The integrated assembly is composed of at least
two anchors, each having a region for insertion into the bone and a
region for suture connection and at least one knotless suture attached to
the suture connection region of each anchor. In one embodiment, at least
one or both of the anchors is cannulated.
[0017] In accordance with another aspect of the present invention, the
assembly includes the suture being attached eccentrically to the
insertion region of at least one of the anchors.
[0018] In accordance with another aspect of the present invention, the
system further includes a gun for firing the assembly.
[0019] In accordance with another aspect of the present invention, the
system further includes a grasper tool having at least one cannulated
barrel.
[0020] In accordance with still another aspect of the present invention,
the system includes an initial anchor impactor tool and a final impactor
tool, each of said
tools adapted to apply force to at least one of the
anchors for insertion into soft tissue and/or bone.
[0021] In accordance with still another aspect of the present invention,
the system for attaching soft tissue to bone includes an assembly that is
composed of at least two anchors, each having a region for insertion into
the bone and a region for suture connection. The region for suture
connection on at least one anchor includes a rotatable collar that can
rotate relative to that anchor so that the suture is prevented from
rotational movement with the anchor as the anchor is rotated, such as
during insertion into the bone or other areas.
[0022] In accordance with still another aspect of the present invention, a
method for attaching soft tissue to bone is provided. The method includes
inserting at least two guidewires through the soft tissue and into the
bone, inserting at least two anchors along the guidewires with the
anchors being connected by a suture and thereafter inserting the anchors
into the bone.
[0023] In accordance with another aspect of the present invention, a
method for attaching soft tissue to bone is provided that comprises
providing an assembly for attaching soft tissue to bone wherein the
assembly is composed of at least two anchors, each anchor having an
insertion region for insertion into the bone and a suture region for
suture connection and a suture attached to the suture connection region
of each anchor into the bone while the suture is attached to the suture
connection region of each anchor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a top view of the preferred embodiment of a dual-anchor
according to the present invention.
[0025] FIG. 2 is a side sectional view of the dual-anchor embodiment of
FIG. 1 taken along line 2-2 of FIG. 1.
[0026] FIG. 3 is a side elevation view, partly in section, of another
dual-anchor embodiment in accordance with the present invention.
[0027] FIG. 4 is a top view of the dual-anchor embodiment of FIG. 3.
[0028] FIG. 5 is a side elevation view of another dual-anchor embodiment
according to the invention.
[0029] FIG. 6 is a perspective view of the grasper tool according to the
present invention.
[0030] FIG. 7 is a sectional view of the grasper tool of FIG. 6 taken
along line 7-7 of FIG. 6.
[0031] FIG. 8 is a side view, partly in section, showing use of the
grasper tool according to the present invention.
[0032] FIG. 9 is a side view, partly in section, showing use of the drill
bit according to the present invention.
[0033] FIG. 10 is a side sectional view showing insertion of the
dual-anchor into the bone according to the present invention.
[0034] FIG. 11 is a side sectional view showing use of an initial anchor
impactor according to the present invention.
[0035] FIG. 12 is a perspective view of the initial anchor impactor and a
final impactor in accordance with the present invention.
[0036] FIG. 13 is a side sectional view showing use of the final impactor
in accordance with the present invention.
[0037] FIG. 14 is a side view, partly in section, of a reattachment of
soft tissue to bone utilizing the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0038] The present invention provides a knotless suture anchor assembly
for use in attaching soft tissue to bone having more points of fixation
per suture than the prior art. Although useful in an open setting, the
assembly of the invention is especially well suited for use in a closed,
or arthroscopic or endoscopic setting.
[0039] In accordance with the invention, the assembly comprises two or
more anchors. The anchors comprise at least two regions: a region for
insertion into the bone and a region for suture attachment. The invention
encompasses anchors in which the two regions overlap in their entirety,
in part, and not at all.
[0040] The anchors of the invention may be cannulated or non-cannulated.
For ease of positioning and inserting the anchors in the bone, cannulated
anchors are preferred. FIGS. 1 and 2 show the sectional and side views of
the preferred embodiment of the dual-anchor suture. Dual-anchor suture 10
has two anchors 20. A typical anchor is approximately 1 to 1.5
centimeters in length and 4-5 millimeters in width. Anchor 20 tapers
slightly near its bottom end but does not need to form a sharp point. In
the preferred embodiment, both anchors 20 are identical but it is
understood that they can be of different dimensions or materials. For
cannulated anchors, round opening 25 may run through the entire body of
anchor 20. These may be of star design to facilitate insertion in an
arthroscopic environment.
[0041] On each of the anchors 20, there is at least one barb 40 oriented
in a way that facilitates the insertion of the anchors into soft tissue
and bone but prevents the anchors from pulling out. Barbs 40 are
typically 2 millimeters in length. As illustrated, preferably the barbs
are situated at a 45-60 degree angle from the anchor body. Although only
two rows of three barbs are visible on FIG. 2 on each anchor, additional
rows of barbs are usually present. The preferred number of barbs in each
row depends on the size of each anchor. Generally, making the barbs
thicker or bigger or increasing the number of barbs on an anchor will
increase the probability that the anchor will be firmly imbedded in the
bone, therefore increasing the pull-out strength, but also increase the
size of the hole in the bone.
[0042] As it is shown in the drawings of FIGS. 1 and 2, the anchors 20 are
bridged with a suture 30. Suture 30 is typically slightly shorter than
the length of the anchors, approximately 1 centimeter. The suture can be
molded directly into the anchor during manufacture of the same or
otherwise fixed to the anchor prior to insertion into a patient's bone.
The suture may be fixed to each anchor approximately one-third or
one-half of the distance from the top of the anchor.
[0043] While the dual-anchor suture described above can be implanted
utilizing open surgery procedures, it is within the scope of this
invention to adapt the multi-anchor suture for arthroscopic use.
Arthroscopic surgery is less invasive and promotes faster healing and
recovery for the patient. Multiple anchor systems are cannulated for
arthroscopic use.
[0044] The anchors of the invention need not have a cannula that extends
through the center vertical axis of anchor 20. The anchors of the
invention may have a cannula that is off-center. As described in detail
below, the cannulation of the anchors permits insertion of an anchor
along a guide wire, thereby facilitating proper placement of the anchor
and helping to avoid inadvertent dropping of the anchor into the surgical
wound area.
[0045] The anchors of the invention are able to become well attached to
the bone to prevent inadvertent removal. To facilitate or strengthen this
attachment, the anchors may be conical in shape. The anchors of the
invention may also have other shapes, as shape, alone, is not the only
method within the scope of the invention for ensuring proper attachment
of the anchor to bone. Anchors having barbs or flanges or threads, and
any other protrusion or invaginations are also within the scope of the
invention. In addition, anchors having a surface coated with an adhesive
material or comprising an adhesive component are also within the scope of
the invention. Any anchor having an outside surface having a shape or
composition that is adapted to adhere to bone is within the scope of the
invention.
[0046] FIGS. 3 and 4 illustrate another example of the dual-anchor system.
Anchors 21 have regions for connection to suture 31 and regions for
tissue insertion. The exterior of anchors 21 have threads 35 for
insertion and fixation in the soft tissue and bone mass by screwing
anchors 21 into the bone mass and/or soft tissue. As the shape and
structure of the anchors of the invention can vary in unlimited ways,
different insertion instruments will be adapted to facilitate the
insertion of the different variations of the invention into soft tissue
and bone.
[0047] As is well within the skill in the art to determine, it may also be
preferable that an anchor of the invention, especially one having a
threaded exterior, also be equipped with a region 48 that is adapted for
receiving an applied torsional force. Such a region, or portion thereof,
may be so adapted to be slotted like the head of a standard screw, or to
be polygonal like an exterior surface of a standard nut, or to have a
polygonal or star shaped cavity therein, such as the cavity typically
found in the head of a screw that is adapted to receive an Allen wrench,
or to have any of the many other similar shapes well known in the
fastener art, or any other shape that is adapted to receive an applied
torsional force. Preferably, region 48 is star shaped. During twisting of
anchor 21, it is important that suture 30 not wrap around anchor 20 and
weaken, break off or lose some of the effective length of the suture. In
FIG. 3, collar 45 of left anchor 21 is illustrated in sectional view to
show how collar 45 rotates independent of anchor 21. Collar 45 rotates
about the anchor so that suture 31 does not wrap around the anchor during
insertion and twisting of the anchor into the bone. Preferably, collar 45
is made of the same material as anchor 21. Suture 31 is molded directly
into collar 45. Alternatively, instead of collar 45, suture 31 may form a
loop around anchor 21 that performs a similar function as collar 45 does.
[0048] FIG. 5 illustrates yet another example of the dual-anchor suture
10. Flexible anchors 22 are in an approximate V-shape and collapse upon
insertion into the bone. In this embodiment, the suture is fixed to the
end of the top barb of each anchor.
[0049] The anchors of the invention include anchors made of bioabsorbable
materials as well as anchors made of non-bioabsorbable materials.
Bioabsorbable materials within the scope of the invention include
polyglycolic acid, polylactic acid, and co-polymers of polylactic acid
and polyglycolic acid. Other bioabsorbable materials within the scope of
the invention are well known in the art and are described more fully in
"Orthopedic Applications for PLA-PGA Biodegradable Polymers," Arthroscopy
Vol. 14: 726-37 (1998), by KA Athanaion, et al. A preferred bioabsorbable
resinous material for constructing the anchors of the present invention
is disclosed in Kaplan et al., U.S. Pat. No. 4,523,591. Non-bioabsorbable
materials within the scope of the invention include stainless steel or
titanium. Other non-bioabsorbable materials are also within the scope of
the invention. If metallic suture anchors are used, to avoid joint
destruction, no metal should protrude from bone or appear in the
articular surface of any joint.
[0050] The anchors of the invention are connected at their connection
regions by one or more sutures. The preferred suture materials are either
non-absorbable or absorbable materials having long half life. Appropriate
suture materials include absorbable materials such as Vicryl and Panacryl
and non-absorbable materials such as Dexon, Ethibond, and Tevdeck. These
materials are available from commercial sources such as United States
Surgical Corp. of Norwalk, Conn. and Ethicon, a subdivision of Johnson &
Johnson of Rutherford, N.J.
[0051] The suture can be connected eccentrically to the anchors. The
eccentric position of the suture on the anchor will cause at least the
insertion region to rotate or turn when tension is applied to the
anchors. This rotating motion will lock the anchors into bone, fortifying
the affixation of soft tissue to bone.
[0052] An important advantage of the present invention is that no knot in
the suture is necessary. The need for suture knots is avoided because the
sutures of the invention are tethered by more than one anchor. The
problems of knot tying and potential knot slippage are thereby avoided.
In addition, once inserted inside the exact place, the multi-anchor
suture holds the tissue and bone in place and creates multiple points of
fixation--for example, anchors vertically holding soft tissue to bone and
the connecting suture member forming a horizontal mattress suture. Thus,
the invention provides more than one point of suture to device fixation
per device and more than one point of device to bone fixation per device.
[0053] In accordance with the invention, the assembly may comprise two or
more anchors and one or more sutures. Assemblies having more anchors than
sutures are within the scope of the invention, as are assemblies having
fewer anchors than sutures, as well as assemblies having the same number
of anchors and sutures. Anchors with connection regions having larger
geometries may be particularly well suited for use in assemblies having a
ratio of sutures to anchors that is greater than otherwise, especially if
greater than one.
[0054] Although the assembly according to the invention may include more
than two anchors and more than one suture, a fill understanding of the
operation and benefits of the invention may most easily be grasped from a
review of an example having only two anchors and one suture. Accordingly,
instruments for insertion of anchor assemblies will also be illustrated
as those for an assembly having two anchors and one suture. However, the
discussion of this exemplary assembly is intended only to provide an
illustrative example and is not intended to limit the scope of the
claimed invention in any way. Neither are the instruments for anchor
insertion limited to those adopted for the exemplary anchor assembly.
[0055] For purposes of the discussion of this example, the following
background information is useful: a bone surface is prepared for surgery.
An area of tendon or ligament avulsion is exposed and prepared for
attachment of soft tissue to bone. Preparation of the bone surface
creates a bleeding bed to ensure an adequate blood supply and scar tissue
formation for proper soft tissue and bone healing.
[0056] Arthroscopic insertion of the dual-anchor suture may be performed
inside of an arthroscopic cannula. Such arthroscopic cannulae are well
known in the art including, for example, in U.S. Pat. No. 5,840,078,
which describes a soft tissue positioning instrument. Such cannulae are
well known in the art and are readily available from Arthrex of Naples,
Fla., Acufex of Smith & Nephew, Inc. of Andover, Mass., and Surgical
Dynamics of Norwalk, Conn. The arthroscopic cannula allows insertion of
instruments and anchors without the risk of catching or being wrapped up
in soft tissue. The cannula also may provide an arthroscopic surgical
work area.
[0057] A double cannulated tubular guide, grasper, or trochar is then
inserted telescopically through the arthroscopic cannula. Appropriate
guides are well known in the art and are readily available from Arthrex,
Smith & Nephew, Inc., Linvatec Corp. of Largo, Fla., and Bionx Implants
Inc. of Blue Bell, Pa. The guide may have spikes at a distal end to hold
soft tissue to bone. This ensures adequate soft tissue capture and exact
location of the suture anchors.
[0058] FIG. 6 shows a perspective view of grasper 32 adapted for a
dual-anchor suture of the invention. A pair of cannulated barrels 36 are
joined on top of grasper body 37. The barrels 36 can also be fixed below
the grasper body 37. Grasper 32 has a jaw 34 at the distal end to grasp
soft tissue at a certain location.
[0059] FIG. 7 is a sectional view of the grasper adapted for the current
invention. The pair of barrels 36 are cannulated to allow guide wires 38
to go through. There need be sufficient clearance between barrels 36 and
jaw 34 to permit insertion of wires 38. The two barrels 36 are at a small
distance apart from each other. This distance can be approximately 6 mm,
depending on the diameter of each anchor and the length of the suture.
This distance will allow sufficient horizontal bone bridge between two
anchors.
[0060] Turning now to FIG. 8, grasper 32 is used to control the location
of soft tissue 70. A pair of guide wires 38, or K-wires, are then
inserted into soft tissue 70 and bone 60 through the tubular guides or
the double barrels connected with a grasper. Such guide wires are well
known in the art and are readily available from DePuy OrthoTech of Tracy,
Calif. The guide wires are drilled into bone to a pre-marked line on the
wires, typically about 1.5 to 2.0 centimeters from the end of the wires
(and thus, 1.5 to 2.0 centimeters into the bone). Alternatively, the
wires may be attached to the bone by means other than drilling, such as
by taping. This preliminarily secures the soft tissue to the bone and
will facilitate insertion of the anchors in the bone mass.
[0061] As illustrated in FIG. 9 cannulated drill 72 bit may then be
inserted over guide wires 38 and used to bore into the surface of the
bone 60 in the area where the guide wire is inserted thereby forming a
bore in the bone that is adapted to receive the anchors. Typically, the
bone is bored to a depth of approximately 8 millimeters. A drill bit may
be used over each guide wire 38. Appropriate drill bits and drill
mechanisms also are well known in the art and are readily available from
Arthrex, Bionx Implants, Inc., and Innovasive Devices, Inc. of
Marlborough, Mass. Alternatively, no bore may be needed. The drill bit
will also have a scribe marking to ensure a sufficient channel for
insertion of the anchor.
[0062] FIG. 10 illustrates the cannulated suture anchors being inserted
over the guide wires 38 and into the bores. Opening 25 on each end anchor
20 is slightly larger than the cross section of wires 38. It is
understood that although opening 25 and wire 38 preferably have a
circular cross section, any cross-sectional shapes will work, including
square and elliptical, as long as anchor 20 can fit over wire 38. Anchors
20 slide down wire 38 into position. Barbs 40 may bend slightly during
insertion of the anchor into the bone. A pair of cannulated tamps can
help seat the dual-anchor suture 10 and counter-sink the anchors.
Cannulated tamps are well known in the art and are readily available from
Bionx Implants Inc. and Acufex of Smith & Nephew, Inc.
[0063] Alternatively, an initial anchor impactor is adapted for the
current invention. FIG. 11 shows use of an initial anchor impactor 100
and FIG. 12 shows a side view of impactor 100. The initial impactor 100
has a tubular body 104 that is double cannulated for passing through a
pair of guide wires 90. The initial impactor 100 has an extended
protrusion platform 102 at its distal end. Although FIG. 12 shows
platform 102 on one side of the tubular body 104, this platform can be on
either or both sides of the tubular body 104. In addition, platform 102
can be of any size or shape as long as it allows a mallet to tap the
initial impactor 100 down to help insertion of the suture anchors. A
region of the initial impactor 100 is shaped to fit the top of the suture
anchors, allowing even pressure on the anchors in direction D. Initial
impactors are made of strong materials suitable for surgical use such as
316 L stainless steel or other similar metal alloy.
[0064] An initial anchor impactor as shown in FIGS. 10 and 11 can push the
suture anchors down into soft tissue and bone to the same level. However,
insertion using an initial anchor impactor may only put the anchors
partially through soft tissue and bone. A final impactor 120 may be
needed to complete insertion of the suture anchors and tensioning of the
suture material, thus optimizing soft tissue attachment to bone.
[0065] Referring now to FIGS. 12 and 13, a final impactor or tensioner 120
having a single cannula is used to tension the suture and fully impact
each anchor into the bone. The final impactor is cannulated so that it
can be inserted along a guide wire to reach the anchors. The final
impactor 120 has an elongated tubular body 122. A region of the final
impactor has a handle 125 that extends perpendicular to the longitudinal
axis of the tubular body 122. The handle 125 can be on any side or both
sides of the tubular body 122 and can be of any shape or size as long as
force can be applied to the handle to tap down an anchor into bone. The
final impactor 120 has a region 130 adapted to operatively engage the top
of an anchor so as to permit downward force in direction D to be
transmitted to the anchor. Region 130 is approximately the same size as
the top of anchor 20. Final impactor 120 is utilized separately on each
anchor. It is preferable that anchors 20 are inserted into the bone so
that the top of anchor 20 is approximately 5-6 millimeters into the bone.
At this point, suture 30 will be taut locking soft tissue 70 adjacent to
bone 60. Like an initial anchor impactor, a final impactor can be made of
316 L stainless steel or similar strength alloy.
[0066] Complete seating of the anchors in the bone can be done by
alternating the single final impactor over each guide wire and slightly
tapping each anchor into place. Complete seating of the anchor suture
forms vertical anchor fixations as well as a horizontal mattress suture.
With the impactor in place, the guide wire can then be removed with
pliers or a drill. The same technique can be repeated to remove the rest
of guide wires.
[0067] Other instruments can also be adapted for use with the multi-anchor
suture assembly of the invention. One such alternative is a gun
pre-loaded with the anchor suture assemblies. A gun can be used to
deliver non-cannulated anchor suture as well as cannulated suture
assemblies. Guns for delivery of non-cannulated anchors have been
described previously by Surgical Dynamics of Norwalk, Conn.
[0068] A gun may also be cannulated to fire cannulated multi-anchor suture
assemblies into soft tissue and bone. A gun having cannulated holes can
be pre-loaded with cannulated anchor assemblies. The gun can then be fit
over guide wires for exact placement of the anchor assemblies. The anchor
assemblies can then be fired with sufficient velocity to penetrate soft
tissue and bone. Using a gun to deliver a multi-anchor suture may
eliminate the need for pre-drilling holes and avoid the use of additional
instrumentation. Anchor insertion with guns may be significantly faster
where multiple insertions are necessary.
[0069] Depending on the surgical situation, a single or multiple anchor
suture assemblies may be needed to accomplish proper repairs of soft
tissue to bone connection. As is well within the skill in the art to
recognize and perform, and depending upon the type and severity of the
soft tissue to bone attachment that is required, more than one device of
the invention may be used in concert. For example, multiple dual-anchor
sutures may be required. FIG. 14 illustrates a cross-sectional view of
soft tissue-bone attachment using more than one dual-anchor suture. As
one integrated assembly, the suture anchor 10 is inserted through soft
tissue and bone. The multiple anchors of one suture assembly provide
multiple points of vertical fixation. In addition, the suture assembly
provides horizontal tension to strengthen soft tissue to bone attachment.
Each anchor may be separated by distances such as at least 5 mm to leave
some bony bridge between the anchors. For multiple suture assemblies, the
anchors may be staggered from the edge of the tuberosity toward the joint
by distances including 5 mm. Multiple insertions of the anchor suture
assemblies expand the area for soft tissue to bone repair.
[0070] It would be within the skill in the art based upon this disclosure
to use any combination of the multiple anchor sutures of the invention
during the same operation to allow ideal apposition of the entire avulsed
soft tissue structure to bone.
[0071] The present invention is not to be limited in scope by the specific
embodiments described herein. Modifications thereof will become apparent
to those in the art based on the teachings of the foregoing description
and drawings. Such modifications fall within the scope of the claimed
invention.
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