U.S. patent application number 11/498460 was filed with the patent office on 2006-11-30 for devices and methods for repairing soft tissue.
Invention is credited to Gregory H. Bain, Seth A. Foerster, Norman S. Gordon, Mark A. Ritchart, George White.
Application Number | 20060271105 11/498460 |
Document ID | / |
Family ID | 32297629 |
Filed Date | 2006-11-30 |
United States Patent
Application |
20060271105 |
Kind Code |
A1 |
Foerster; Seth A. ; et
al. |
November 30, 2006 |
Devices and methods for repairing soft tissue
Abstract
Devices and methods are disclosed for securing soft tissue to
bone, and particularly for axially anchoring suture which attaches
the soft tissue to adjacent bone structure.
Inventors: |
Foerster; Seth A.;
(Clemente, CA) ; Gordon; Norman S.; (Irvine,
CA) ; Ritchart; Mark A.; (Murrieta, CA) ;
Bain; Gregory H.; (Laguna Niguel, CA) ; White;
George; (Corona, CA) |
Correspondence
Address: |
ARTHROCARE CORPORATION
680 VAQUEROS AVENUE
SUNNYVALE
CA
94085-3523
US
|
Family ID: |
32297629 |
Appl. No.: |
11/498460 |
Filed: |
August 2, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10299171 |
Nov 19, 2002 |
7090690 |
|
|
11498460 |
Aug 2, 2006 |
|
|
|
Current U.S.
Class: |
606/232 |
Current CPC
Class: |
A61B 2017/0409 20130101;
A61B 2017/0412 20130101; A61B 2017/0424 20130101; A61B 2017/0437
20130101; A61B 2017/0414 20130101; A61B 2017/0427 20130101; A61B
2017/0453 20130101; A61B 2017/0454 20130101; A61B 2017/045
20130101; A61B 2017/0435 20130101; A61B 2017/042 20130101; A61B
17/0401 20130101; A61B 2017/0451 20130101 |
Class at
Publication: |
606/232 |
International
Class: |
A61B 17/04 20060101
A61B017/04 |
Claims
1. A suture anchoring device, comprising: an anchor housing having
an outer wall; a compressible plug member disposed within said
housing and extending proximally of said housing; a channel
extending through said plug member for accommodating a length of
suture; and a cap member for enclosing a proximal end of said
housing; wherein said plug member is compressed in order to anchor
the length of suture when said cap member is engaged with said
housing.
2. A suture anchoring device, comprising: an anchor body having an
interior threaded wall; a suture return member associated with said
body for returning a distally extending length of suture in a
proximal direction; a length of fiber having a first end secured to
a distal portion of said body, and a second end extending from an
end of said body, said fiber being wrapped about the interior
threaded wall of said body a plurality of times; whereby when said
length of fiber is pulled in a predetermined direction, the wrapped
fiber becomes tightly engaged about said suture to anchor said
suture.
3. The suture anchoring device as recited in claim 2, wherein said
first end of said fiber is secured to said suture return
member.
4. The suture anchoring device as recited in claim 3, and fuirther
comprising a pin disposed on a proximal end of said body about
which the second end of fiber is disposed. a first plate having a
suture receiving aperture disposed therein; a second plate having a
suture receiving aperture disposed therein, and a connection
between said first and second plates which is designed to break
when a predetermined force is applied thereto; wherein axial
displacement of one of said plates relative to the other of said
plates creates a tortuous path for a length of suture passing
therethrough.
5. A suture anchoring device, comprising: an outer tube having a
lumen extending axially therethrough; a length of suture extending
distally through said outer tube, about a suture return member, and
proximally back through said outer tube; and an inner expandable
member extending axially through said lumen, between portions of
said length of suture, said inner expandable member being
actuatable to a radially expanded state in order to compress and
clamp said length of suture in place.
6. The suture anchoring device as recited in claim 5, wherein said
inner expandable member comprises a split elastomeric tube.
7. The suture anchoring device as recited in claim 5, wherein said
inner expandable member comprises a spring coil.
8. The suture anchoring device as recited in claim 5, and further
comprising a tapered pin for actuating said inner expandable member
to said radially expanded state.
Description
CROSS-REFERENCE TO RELATED CASE
[0001] This application is a continuation application of co-pending
U.S. patent application Ser. No. 10/299,171 to Seth Foerester, et
al. filed Nov. 19, 2002, the subject matter being incorporated
herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to devices and methods for
repairing soft tissue, and more particularly to devices and methods
for arthroscopic repair of a torn rotator cuff.
[0003] It is an increasingly common problem for tendons and other
soft, connective tissues to tear or to detach from associated bone.
One such type of tear or detachment is a "rotator cuff" tear,
wherein the supraspinatus tendon separates from the humerus,
causing pain and loss of ability to elevate and externally rotate
the arm. Complete separation can occur if the shoulder is subjected
to gross trauma, but typically, the tear begins as a small lesion,
especially in older patients.
[0004] To repair a torn rotator cuff, the typical course today is
to do so surgically, through a large incision. This approach is
presently taken in almost 99% of rotator cuff repair cases. There
are two types of open surgical approaches for repair of the rotator
cuff, one known as the "classic open" and the other as the
"mini-open". The classic open approach requires a large incision
and complete detachment of the deltoid muscle from the acromion to
facilitate exposure. The cuff is debrided to ensure suture
attachment to viable tissue and to create a reasonable edge
approximation. In addition, the humeral head is abraded or notched
at the proposed soft tissue to bone reattachment point, as healing
is enhanced on a raw bone surface. A series of small diameter
holes, referred to as "transosseous tunnels", are "punched" through
the bone laterally from the abraded or notched surface to a point
on the outside surface of the greater tuberosity, commonly a
distance of 2 to 3 cm. Finally, the cuff is sutured and secured to
the bone by pulling the suture ends through the transosseous
tunnels and tying them together using the bone between two
successive tunnels as a bridge, after which the deltoid muscle must
be surgically reattached to the acromion. Because of this maneuver,
the deltoid requires postoperative protection, thus retarding
rehabilitation and possibly resulting in residual weakness.
Complete rehabilitation takes approximately 9 to 12 months.
[0005] The mini-open technique, which represents the current
growing trend and the majority of all surgical repair procedures,
differs from the classic approach by gaining access through a
smaller incision and splitting rather than detaching the deltoid.
Additionally, this procedure is typically performed in conjunction
with arthroscopic acromial decompression. Once the deltoid is
split, it is retracted to expose the rotator cuff tear. As before,
the cuff is debrided, the humeral head is abraded, and the
so-called "transosseous tunnels", are "punched" through the bone or
suture anchors are inserted. Following the suturing of the rotator
cuff to the humeral head, the split deltoid is surgically
repaired.
[0006] Although the above described surgical techniques are the
current standard of care for rotator cuff repair, they are
associated with a great deal of patient discomfort and a lengthy
recovery time, ranging from at least four months to one year or
more. It is the above described manipulation of the deltoid muscle
together with the large skin incision that causes the majority of
patient discomfort and an increased recovery time.
[0007] Less invasive arthroscopic techniques are beginning to be
developed in an effort to address the shortcomings of open surgical
repair. Working through small trocar portals that minimize
disruption of the deltoid muscle, a few surgeons have been able to
reattach the rotator cuff using various bone anchor and suture
configurations. The rotator cuff is sutured intracorporeally and an
anchor is driven into bone at a location appropriate for repair.
Rather than thread the suture through transosseous tunnels which
are difficult or impossible to create arthroscopically using
current techniques, the repair is completed by tying the cuff down
against bone using the anchor and suture. Early results of less
invasive techniques are encouraging, with a substantial reduction
in both patient recovery time and discomfort.
[0008] Unfortunately, the skill level required to facilitate an
entirely arthroscopic repair of the rotator cuff is inordinately
high. Intracorporeal suturing is clumsy and time consuming, and
only the simplest stitch patterns can be utilized. Extracorporeal
knot tying is somewhat less difficult, but the tightness of the
knots is difficult to judge, and the tension cannot later be
adjusted. Also, because of the use of bone anchors to provide a
suture fixation point in the bone, the knots that secure the soft
tissues to the anchor by necessity leave the knot bundle on top of
the soft tissues. In the case of rotator cuff repair, this means
that the knot bundle is left in the shoulder capsule where it can
be felt by the patient postoperatively when the patient exercises
the shoulder joint. So, knots tied arthroscopically are difficult
to achieve, impossible to adjust, and are located in less than
optimal areas of the shoulder. Suture tension is also impossible to
measure and adjust once the knot has been fixed. Consequently,
because of the technical difficulty of the procedure, presently
less than 1% of all rotator cuff procedures is of the arthroscopic
type, and is considered investigational in nature.
[0009] Another significant difficulty with current arthroscopic
rotator cuff repair techniques is shortcomings related to currently
available suture anchors. Suture eyelets in bone anchors available
today, which like the eye of a needle are threaded with the thread
or suture, are small in radius, and can cause the suture to fail at
the eyelet when the anchor is placed under high tensile loads.
[0010] There are various bone anchor designs available for use by
an orthopedic surgeon for attachment of soft tissues to bone. The
basic commonality between the designs is that they create an
attachment point in the bone for a suture that may then be passed
through the soft tissues and tied, thereby immobilizing the soft
tissue. This attachment point may be accomplished by different
means. Screws are known for creating such attachments, but existing
designs suffer from a number of disadvantages, including their
tendency to loosen over time, requiring a second procedure to later
remove them, and their requirement for a relatively flat attachment
geometry.
[0011] Another approach is to utilize the difference in density in
the cortical bone (the tough, dense outer layer of bone) and the
cancellous bone (the less dense, airy and somewhat vascular
interior of the bone). There is a clear demarcation between the
cortical bone and cancellous bone, where the cortical bone presents
a kind of hard shell over the less dense cancellous bone. The
aspect ratio of the anchor is such that it typically has a longer
axis and a shorter axis and usually is pre-threaded with a suture.
These designs use a hole in the cortical bone through which an
anchor is inserted. The hole is drilled such that the shorter axis
of the anchor will fit through the diameter of the hole, with the
longer axis of the anchor being parallel to the axis of the drilled
hole. After deployment in to the cancellous bone, the anchor is
rotated 90.sup.B so that the long axis is aligned perpendicularly
to the axis of the hole. The suture is pulled, and the anchor is
seated up against the inside surface of the cortical layer of bone.
Due to the mismatch in the dimensions of the long axis of the
anchor and the hole diameter, the anchor cannot be retracted
proximally from the hole, thus providing resistance to pull-out.
These anchors still suffer from the aforementioned problem of
eyelet design that stresses the sutures.
[0012] Still other prior art approaches have attempted to use a
"pop rivet" approach. This type of design requires a hole in the
cortical bone into which a split shaft is inserted. The split shaft
is hollow, and has a tapered plug leading into its inner lumen. The
tapered plug is extended out through the top of the shaft, and when
the plug is retracted into the inner lumen, the tapered portion
causes the split shaft to be flared outwardly, ostensibly locking
the device into the bone.
[0013] Other methods of securing soft tissue to bone are known in
the prior art, but are not presently considered to be feasible for
shoulder repair procedures, because of physicians' reluctance to
leave anything but a suture in the capsule area of the shoulder.
The reason for this is that staples, tacks, and the like could
possibly fall out and cause injury during movement. As a result
ofthis constraint, the attachment point often must be located at a
less than ideal position. Also, the tacks or staples require a
substantial hole in the soft tissue, and make it difficult for the
surgeon to precisely locate the soft tissue relative to the
bone.
[0014] As previously discussed, any of the anchor points for
sutures mentioned above require that a length of suture be passed
through an eyelet fashioned in the anchor and then looped through
the soft tissues and tied down to complete the securement. Much
skill is required, however, to both place the sutures in the soft
tissues, and to tie knots while working through a trocar under
endoscopic visualization.
[0015] What is needed, therefore, are new approaches for repairing
the rotator cuff or fixing other soft tissues to bone, wherein both
the bone and suture anchors reside completely below the cortical
bone surface, there is no requirement for the surgeon to tie a knot
to attach the suture to the bone anchor, and wherein suture tension
can be adjusted and possibly measured. The procedures associated
with the new approaches should be better for the patient than
existing procedures, should save time, be uncomplicated to use, and
be easily taught to practitioners having skill in the art.
SUMMARY OF THE INVENTION
[0016] Accordingly, the inventors have developed new and novel
approaches for securing soft tissue to bone, and particularly for
axially anchoring suture which attaches the soft tissue to adjacent
bone structure.
[0017] More particularly, in one aspect of the invention there is
disclosed a suture anchoring device, comprising an anchor housing
having an outer wall, a compressible plug member disposed within
the housing and extending proximally of the housing, and a channel
extending through the plug member for accommodating a length of
suture. A cap member is provided for enclosing a proximal end of
the housing. In operation, the compressible plug member is
compressed in order to anchor the length of suture when the cap
member is engaged with the housing.
[0018] In another aspect of the invention, there is disclosed a
suture anchoring device which comprises an anchor body having an
interior threaded wall, as well as a suture return member
associated with the body, such as a pin, for returning a distally
extending length of suture in a proximal direction. A length of
fiber is provided, having a first end secured to a distal portion
of the body, and a second end extending from an end of the body,
the fiber being wrapped about the interior threaded wall of the
body a plurality of times. In operation, when the length of fiber
is pulled in a predetermined direction, the wrapped fiber becomes
tightly engaged about the suture to anchor the suture.
[0019] In yet another aspect of the invention, there is provided a
suture anchoring device, which comprises an anchor body having an
outer wall, and a suture return member disposed at a distal end of
the anchor body, for receiving a length of suture extending
distally through the body, and returning a portion of the suture
length in a proximal direction. A passage extends along an interior
surface of the wall for accommodating the length of suture. The
passage tapers in width in a proximal direction, for the purpose of
permitting the suture to be moved axially when pulled in a first
direction, for approximating a portion of soft tissue to which the
suture was attached to adjacent bone, and anchoring the suture
axially in place when the suture is pulled in an opposing
direction.
[0020] In still another aspect of the invention, there is provided
a suture anchoring device, comprising an anchor body having an
outer wall, as well as a lumen for accommodating a length of suture
within the outer wall. A plurality of members are disposed within
the anchor body for contacting the length of suture and creating a
tortuous path therefor, in order to anchor the length of suture in
place. The device further comprises a member radially extending
from the body for anchoring the device in adjacent bone.
[0021] In another aspect of the invention, there is provided a
suture anchoring device, which comprises an axially extending
spring, as well as a suture return member or pin disposed distally
of said spring. A length of suture extends axially within the
spring and about the suture return member. An actuator is disposed
at a proximal end of the device for actuating the spring to a
compressed state wherein the suture becomes clamped within the
spring.
[0022] In yet another aspect of the invention, there is provided a
suture anchoring device, which comprises a suture return member and
a length of suture extending axially through the device about the
suture return member. A plurality of axially stacked, spaced
plates, comprising leaf springs, are disposed proximally of the
suture return member. The aforementioned length of suture extends
through apertures in each of the plates. A mandrel is provided for
moving the plurality of stacked plates between a first generally
planar orientation, wherein the suture is free to move axially
therethrough, and a second folded orientation, wherein the suture
is axially clamped within the apertures.
[0023] In still another aspect of the invention, there is provided
a suture anchoring device, which comprises a body, a core disposed
within the body, and a length of suture attached to a piece of soft
tissue and extending into the body. A portion of the length of
suture is wrapped about the core and attached to a distal end
thereof. The core is rotatable to adjustably tension the length of
suture, and may be rotationally locked in order to anchor the
length of suture in place.
[0024] In another aspect of the invention, there is provided a
suture anchoring device, which comprises an outer tube, as well as
a first plate having a suture receiving aperture disposed therein.
A second plate has a suture receiving aperture disposed therein. A
connection between the first and second plates is designed to break
when a predetermined force is applied thereto. The system is
designed so that axial displacement of one of the plates relative
to the other of the plates causes application of the predetermined
force, to separate the plates, and thus create a tortuous path for
a length of suture passing therethrough.
[0025] In still another aspect of the invention, there is provided
a suture anchoring device. This device comprises an outer tube
having a lumen extending axially therethrough, and a length of
suture extending distally through the outer tube, about a suture
return member, and proximally back through the outer tube. An inner
expandable member extends axially through the lumen, between
portions of the length of suture, the inner expandable member being
actuatable to a radially expanded state in order to compress and
clamp the length of suture in place. In one embodiment, the inner
expandable member comprises a split elastomeric tube, while in a
second embodiment, the inner expandable member comprises a spring
coil.
[0026] The invention, together with additional features and
advantages thereof, may best be understood by reference to the
following description taken in conjunction with the accompanying
illustrative drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG 1A is a partial sectional view through the left shoulder
of a human as seen from the front showing the use of a minimally
invasive soft tissue to bone attachment system, or suture anchor
system, of the present invention;
[0028] FIG. 1B is an enlarged sectional view taken within the
circle denoted 1B in FIG. 1A;
[0029] FIGS. 1C-1F are enlarged sectional views of several steps in
the use of the suture anchor system of FIG. 1A to reattach a
rotator cuff tendon;
[0030] FIG. 2 is a cross-sectional view of a suture anchor
comprising a compliant plug, in accordance with one embodiment of
the present invention, wherein the suturing material is not secured
in place;
[0031] FIG. 3 is a cross-sectional view similar to FIG. 2, wherein
the cap is secured to the housing of the suture anchor in order to
secure the suturing material in place;
[0032] FIG. 4 is a perspective view of a suture anchor comprising a
drum spinning apparatus, in accordance with another embodiment of
the present invention, wherein the suturing material is not yet
secured in place;
[0033] FIG. 5 is a perspective view similar to FIG. 4, wherein the
suturing material is secured in place;
[0034] FIG. 6 is a cross-sectional view illustrating a cam cleat
suture anchoring apparatus, in accordance with yet another
embodiment of the present invention;
[0035] FIG. 7 is a perspective view of a jam cleat suture anchoring
apparatus, in accordance with still another embodiment of the
present invention;
[0036] FIG. 8 is a cross-sectional view showing another suture lock
embodiment, comprising a multi-lock anchor, prior to
deployment;
[0037] FIG. 9 is a cross-sectional view of the multi-lock anchor
shown in FIG. 8, after it has been deployed to lock the suture;
[0038] FIG. 10 is a perspective view of a spring-locking suture
anchor embodiment, wherein it has not yet been deployed to anchor
the suture in place;
[0039] FIG. 11 is a perspective view of the spring-locking suture
anchor embodiment of FIG. 10, showing the anchor is a deployed
orientation;
[0040] FIG. 12 is a front perspective view of yet another suture
lock embodiment, comprising a plurality of leaf springs in an
undeployed state;
[0041] FIG. 13 is a view similar to FIG. 12, showing the springs in
a deployed state for locking the suture;
[0042] FIG. 14 is a front view of a modified leaf spring suture
locking system, shown in an undeployed state;
[0043] FIG. 15 is a front view similar to FIG. 14, wherein the leaf
springs have been deployed to lock the suture in place;
[0044] FIG. 16 is a perspective view of a vertical knotless bone
and suture anchor which functions to wrap suture around a shaft in
order to lock it in place;
[0045] FIG. 17 is a cross-sectional view of still another suture
anchoring device, shown in an undeployed position;
[0046] FIG. 18 is a cross-sectional view similar to FIG. 17,
illustrating the suture anchoring device after it has been deployed
to anchor the suture in place;
[0047] FIG. 19 is a cross-sectional view taken along lines 19-19 of
FIG. 17;
[0048] FIG. 20 is a cross-sectional view taken along lines 20-20 of
FIG. 18;
[0049] FIG. 21 is a cross-sectional view of still another
embodiment of a suture anchoring device constructed in accordance
with the principles of the present invention, showing the inventive
device prior to insertion of a length of suture;
[0050] FIG. 22 is a cross-sectional view similar to that of FIG.
21, wherein suture is disposed within a cylinder comprising a
portion of the inventive anchoring device;
[0051] FIG. 23 is a cross-sectional view similar to those of FIGS.
21 and 22, wherein a second split tube has been inserted into the
cylinder;
[0052] FIG. 24 is a cross-sectional view similar to that of FIG.
23, wherein the split tube has been expanded to lock the suture in
place;
[0053] FIG. 25 is a cross-sectional end view of another suture
anchoring embodiment, comprising a cylinder in which is disposed a
spring coil and suturing material;
[0054] FIG. 26 is a cross-sectional view similar to FIG. 25,
wherein the spring coil has been expanded to anchor the suturing
material in place; and
[0055] FIG. 27 is a cross-sectional view of still another suture
anchoring embodiment, comprising a binding tapered threaded
anchor.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0056] The present invention provides improved knotless suture
anchor devices and methods for anchoring a length of suture with
respect to a body cavity. In the exemplary embodiments described
herein, the inventive devices are used to anchor a length of suture
to a bone structure, specifically the humeral bone of the human
shoulder. The length of suture is desirably looped through soft
tissue, such as a rotator cuff tendon, to approximate and fix the
soft tissue with respect to the body cavity (e.g., bone structure).
It should be understood, however, that the suture anchor apparatus
described herein may be utilized to secure a length of suture to
body cavities other than in a bone structure, and may even be used
to anchor the suture outside of a body cavity, or merely to a
predetermined location within the body. In this regard, the various
inventive embodiments include an anchor body within which the
length of suture may be anchored without knots. If the anchor body
is to be implanted within the body cavity, structure on its
exterior or coupled therewith may also be provided for securing the
anchor body therein.
[0057] As mentioned, the present invention is particularly
well-suited for repairing rotator cuff injuries by re-attaching the
rotator cuff tendon to the outside of the humeral head. The
invention permits minimally invasive surgeries on such injuries and
greatly facilitates rapid and secure fixation of the rotator cuff
tendon to the humeral head. It should be understood that the same
principles described herein apply to the repair of other injuries
in which soft tissue is to be re-attached to a bone structure.
[0058] FIGS. 1A-1F are cross-sectional views through the left
shoulder of a human as viewed from the front and illustrate the use
of an exemplary soft tissue to bone attachment system, or suture
anchor system 20, for repairing a rotator cuff tendon injury. The
rotator cuff tendon 22 is shown in its natural position overlying
the bulbous humeral head 24 of the humerus bone 26. In rotator cuff
injuries, the tendon 22 partially or completely separates from its
attachment point to the humeral head 24, which point of attachment
is typically located along an angled shelf, the greater tuberosity
28. In minimally invasive surgeries to repair the rotator cuff
injury, the surgeon threads one or more sutures through the rotator
cuff tendon 22 and anchors them to the greater tuberosity 28. The
suture anchor system 20 of the present invention facilitates this
latter step of anchoring the sutures to the greater tuberosity
28.
[0059] With reference first to FIG 1A, a generally tubular trocar
30 provides a conduit through the soft tissue of the shoulder for
passage of the suture anchor system 20 of the present invention.
Per convention, the trocar has a proximal end outside of the
patient that the surgeon manipulates, and a distal probe or end
that enters the body and through which the surgery is performed.
Typically, the surgeon makes an incision or stab wound through the
outer dermal layers of sufficient size to permit passage of the
trocar 30 through the skin and the deltoid muscle, into proximity
with the humeral head 24. Various trocars and techniques for
creating the approach passageway are known and may be utilized with
the present invention. In addition, more than one incision and
conduit may be necessary to perform the several suturing and
anchoring steps.
[0060] After establishing one or more direct conduits to the
humeral head 24, the surgeon passes a length of suture through the
soft tissue of the rotator cuff tendon 22 so that a loop 32 of
suture material is embedded therein, as seen in FIG. 1B. The two
free ends 34a, 34b of the length of suture are withdrawn from the
patient and coupled to the suture anchor system 20. The specifics
of this coupling and subsequent manipulation of the two free ends
of the suture will be described more fully below, in conjunction
with each of the described embodiments. For the purpose of
explaining the exemplary method of use, it is sufficient to
understand that the two free ends 34a, 34b pass through or about
the suture anchor system 20. Therefore, the two free ends 34a, 34b
are shown at the top of FIG. 1B projecting from a proximal end of
the system 20.
[0061] The exemplary suture anchor system 20 as illustrated is
particularly suitable for anchoring a suture to a body cavity,
specifically the humeral head 24 as shown. When anchoring sutures
to such a bone structure, a conventional technique is to first form
a blind hole or cavity 40 through the cortical layer 42 and into
the soft cancellous matter 44, as seen in Figs. 1B and 1C. The
surgeon then positions a suture anchor 46 within the cavity 40 and
secures it therein to prevent removal from the cavity.
[0062] The suture anchor 46 performs two functions: anchoring
itself within the body cavity and anchoring the sutures therein. In
the embodiment as illustrated in Figs. 1C and 1D, the former
finction is accomplished using an expandable anchoring member 48
located at the proximal end of the suture anchor 46. The anchoring
member 48 functions like a toggle bolt used in ceiling fixtures,
and specifically expands to a larger dimension in the cavity 40
beyond the hard cortical bone 42. FIG. 1D shows the anchoring
member 48 after having been radially expanded from proximal
movement of the suture anchor 46 (compare to the axial location of
the suture anchor in FIG. 1C). In this manner, the suture anchor 46
is prevented from being removed from the cavity 40 once the
anchoring member 48 is deployed.
[0063] The present invention illustrates a particular anchoring
member 48, although any similar expedient will work. For example, a
different toggle-like anchoring member may be used such as shown
in-co-pending application Ser. No. 09/876, 488 filed on Mar. 2,
2001, expressly incorporated by reference herein. Alternatively, an
anchoring structure that expands into contact with the cancellous
matter 44 or a body resembling a screw may also be used. In short,
the present invention is not considered to be limited by the
particular anchoring structure that secures the suture locking
portion to the bone or other body cavity.
[0064] The second function of the suture anchor 46 is the anchoring
or fixation of the suture with respect to the suture anchor itself,
without the use of knots. Desirably, the particular manner of
anchoring the suture with respect to the suture anchor 46 permits
easy adjustment of the length of suture between the suture anchor
46 and the loop 32 formed in the soft tissue prior to anchoring the
suture. This adjustment allows the surgeon to establish the proper
tension in the length of suture for effective repair of the soft
tissue, and reattachment of the rotator cuff tendon 22 in the
illustrated embodiment. So, for example, FIG. 1D also illustrates
the two free ends 34a, 34b of the length of suture having been
pulled taught prior to securing within the suture anchor 46 (see
comparison with FIG.1C).
[0065] FIG. 1E shows the fully deployed suture anchor 46 after the
free ends 34a, 34b have been placed in tension and locked within
the suture anchor, in various manners to be described below in
connection with the descriptions of each of the several disclosed
embodiments.
[0066] Although not shown, the remaining steps in the procedure
involve withdrawing portions of the suture anchor from the surgical
site as seen in FIG. 1F and severing the free ends 34a', 34b '
close to the suture anchor 46. It should be noted that no portion
of the suture anchor 46 or sutures 34a', 34b ' projects above the
outer surface of the humeral head 24, and in addition no knots are
left to irritate the patient.
[0067] Although the present invention is described primarily in
conjunction with the repair of a torn rotator cuff, the apparatus
and method could also be used in arthroscopic repair at other
sites, such as the knee, elbow, or hip, for example, as well as in
conjunction with other surgical techniques, such as traditional
open or mini-open surgical procedures.
[0068] Now with reference to FIGS. 2 and 3, there is shown a first
embodiment of the present invention. In this embodiment, a suture
anchor 46a comprises a rigid outer housing 50, which may be
fabricated of any suitable rigid biocompatible material. It should
be noted that the usage of the reference numeral 46a is intended to
convey that the inventive embodiment is usable in the procedure
discussed in connection with FIGS. 1A-1F, in place of the suture
anchor 46 disclosed therein, which is illustrative only. Within the
housing 50 is a compliant plug 52, comprised of a suitable
elastomeric material. Channels 54 and 56 extend axially through the
plug 52 and a lower housing portion 58, for accommodating a length
of suture 34 extending therethrough, as shown. The suture anchor
46a further comprises a rigid cap 60, which is engageable with an
upper portion of the housing 50.
[0069] In operation, as shown in FIG. 2, the cap 60 is initially
separated from the housing 50, to permit the length of suture 34 to
be disposed through the channels 54, 56, as shown. When the cap 60
is disengaged from the housing 50, the suture length 34 is freely
movable through the housing 50, by applying a tensile force to one
end or the other of the suture length, in order to tension the
suture and approximate the soft tissue 22 (Figs. 1A-1F) to the bone
24, as desired. Once the attachment procedure described in
connection with FIGS. 1A-1F has been completed, and the soft tissue
22 is satisfactorily in place relative to the bone 24, the cap 60
is engaged with the housing 50 of the compliant plug suture anchor
46, by moving it in the direction of the arrows 62 until lower
engaging portions 64 of the cap 60 and upper engaging portions 66
may be snap-fitted together, as shown in FIG. 3, or otherwise
connected in ways well known in the art, such as a threaded fitting
or other suitable means. The purpose of this step is to anchor the
suture in place, as illustrated in FIG. 1E. Because there is excess
plug material within the housing 50, with a portion 68 extending
above the upper engaging portions 66 of the housing 50, as shown in
FIG. 2, the placement of the cap 60 on the housing 50 causes the
compliant plug material 52 to be significantly compressed within
the housing 50, such that the channels 54, 56 are also compressed,
thereby clamping or locking the suture in place, so that it is no
longer slidable through the channels 54 and 56.
[0070] Now with reference to FIGS. 4 and 5, there is shown an
alternative suture anchoring device 46b, which comprises a
cylindrical insert or body 68 having an interior wall 70, which may
be threaded, as shown. The insert 68 is adapted for disposition
within the blind hole or cavity 40 (FIG. 1D). A suture return
member or primary pin 72 is disposed across the inner diameter of
the insert 68, and may be suitably secured to the interior wall 70
in either a rotatable or fixed fashion, as desired. A secondary pin
74 protrudes from the interior wall 70 at a location above the
primary pin 72. One end 76 of a length of monofilament fiber 78 is
secured to the primary pin 72, and a second end thereof is disposed
about the secondary pin 74 and extends upwardly out of a proximal
end of the insert 68. The majority of the length of monofilament
fiber 78 forms a drum 80 which is threadedly engaged with the
interior wall 70, as illustrated in FIG. 4.
[0071] In operation, the suture length 34 is disposed in the insert
68, from a proximal direction, and wrapped around the primary pin
72, as shown in FIG. 4. The soft tissue 22 is approximated to the
bone 24, as described in connection with FIGS. 1A-1F, by tensioning
the suture 34 such that it moves axially about the primary pin 72.
When this process is completed, and it is desired to lock the
suture in place, the length of monofilament fiber 78 is pulled
proximally, in the direction of arrow 81, thereby causing the drum
80 of monofilament fiber to spin circumferentially. The result of
this process is that the monofilament fiber 78 becomes tightly
wrapped about the suture 34, with multiple loops, as shown in FIG.
5, thus locking the suture 34 in place lengthwise.
[0072] FIG. 7 illustrates still another suture anchor 46c which may
be identified as a "jam cleat" or "boat cleat"--type mechanism.
More particularly, the anchor 46c comprises a generally cylindrical
body portion 82, which preferably includes threads 84 on at least a
portion of its outer surface for engaging adjacent bone within the
blind hole or cavity 40 (FIG. 1B). A pin 86 is disposed across the
internal diameter of the body portion 82, in a manner similar to
the pin 72 in FIGS. 4 and 5, secured at each end to the inner
cylindrical wall 88 in either a fixed or rotatable manner. In use,
the suture 34 extends axially through the cylinder 84 and about the
pin 86, with a first end being attached to the soft tissue 22
(FIGS. 1A-1F) in the direction of arrow 90, and the second end
extending proximally out of the patient's body through an access
cannula (not shown). The portion of the suture length 34 which
extends between the pin 86 and the soft tissue extends through a
cleat portion 92, which comprises a"V" shaped passage 94 that
progressively narrows in a proximal direction, as well as a
plurality of ribs 96. This suture anchoring system operates in a
manner similar to that of a boat cleat, in that the suture 34 may
be pulled proximally through the cannula to tension the soft tissue
against the bone, as desired. The V-shaped passage 94 permits
movement of the suture in this direction, in order to provide the
practitioner performing the procedure with the ability to
selectively tension the soft tissue. However, because of the
progressively narrowing passage diameter in the opposing direction,
the suture cannot be moved in the direction of the arrow 90, thus
effectively locking the suture in place, as well as the soft tissue
22.
[0073] Now with reference to FIG. 6, there is shown yet another
modified embodiment of a suture anchor 46d, which comprises, once
again, a generally cylindrical anchor body 94, within which are
disposed a pair of cam cleats 96, 98. A pin 100 is disposed within
the cylindrical body 94 as well, in the same manner as is the case
for pin 86 in the embodiment of FIG. 7. The suture length 34
extends distally through the cylindrical body 94, is wrapped about
the pin 100, which functions as a suture return member, and is
returned proximally through the cannula (not shown). The first end
102 of the suture 34 is attached to the soft tissue to be repaired,
while the second end 104 is available for the practitioner to use
in tensioning the suture, by applying tension proximally thereon. A
body cap portion 106 is disposed above the main body portion 94.
The cam cleats 96, 98 are pivotally attached to the main body
portion or housing 94 by means of pivot pins 107a, 107b,
respectively. In operation, once the cylindrical body portion 94 is
in position within the bone cavity 40, below the cortical bone
layer, the device is pushed down to release the cleats 96, 98 so
that they pivot about the pivot pins 107a, 107b. This action
separates the cleats 96, 98 sufficiently to permit the suture to be
tightened to tension the soft tissue, by pulling proximally on the
second suture end 104. Tension on the suture 34 creates a force
which attempts to pull the anchor out of the bone cavity 40. This
force creates a moment on the cleats 96, 98, which increases the
radially outward pivoting thereof described above, thus extending
them substantially into the cancellous bone matter 44, as shown in
FIG. 6, so that the device 46d becomes anchored within the bone.
Subsequently, once the soft tissue has been properly positioned and
suitably tensioned, the body 94 is permitted to float upwardly in a
proximal direction, thereby pushing the interior toothed surfaces
108, 110 of each respective cleat 96, 98 together and locking the
suture 34 in place.
[0074] A somewhat similar embodiment to that of FIG. 6 is
illustrated in FIGS. 8 and 9. This embodiment 46e includes a
generally cylindrical body 112. Two suture free ends 34a, 34b
extend axially through a lumen 114 of the body 112. The body 112
comprises an outer cylinder 116 having bone lock apertures 118 and
120, and an inner member 122 comprising internal bone lock members
124, 126, together with designed points of weakness 128 and 130. In
FIG. 8, the device 46e is shown in an undeployed state.
[0075] FIG. 9 illustrates the device 46e in a deployed condition.
Deployment is initiated, in a preferred method, by actuating a
mandrel 132 in a distal direction, as shown by arrows 134, until
the mandrel 132 engages external lock edges 136, 138 on the outer
cylindrical body 116, thereby moving the outer cylinder 116 in a
distal direction as well. At the same time, the inner member 122 is
pulled in a proximal direction, as shown by arrows 140. The distal
movement of outer cylinder 116, in combination with the proximal
movement of inner member 122, causes contact of the internal bone
lock members 124, 126 with portions of the outer cylinder 116 which
define the proximal edges of apertures 118, 120, respectively,
thereby causing the bone lock members 124, 126 to be pushed
radially outwardly so that their ends are engaged with adjacent
cancellous bone 44', as shown in FIG. 9. Thus, the device 46e is
now locked (anchored) axially in the bone and prevented from
proximal movement.
[0076] Once the bone lock feature has been deployed, a
predetermined applied tensile force proximally on the inner member
122 will cause separation of a proximal portion 142 from the
remaining portion of the inner member 122 at the designed point of
weakness 128, as shown in FIG. 9. At this juncture, an inner member
locking portion 144, which has an increased width relative to the
width of remaining portions of the inner member 122, has moved
proximally along an axis of the device 46e sufficiently to be
co-incident with the aperture 120. Consequently, a portion of the
locking portion 144 is caused to slip radially outwardly into the
aperture 120, as shown, in order to axially lock the inner member
relative to the outer member. The forces involved in deploying the
bone lock members 124 and 126 also function to compress the distal
end of the outer wall of the inner member 122, causing the locking
portion 144, and a bulbous portion 146 on an opposing side of the
inner member 122, which is axially offset from the locking portion
144, to overlap one another, as shown in FIG. 9, thus creating a
tortuous path 148 for the suture 34. This tortuous path functions
as a suture lock, preventing the suture 34 from moving axially
within the device 46e.
[0077] Yet another suture anchoring device 46f, which may be called
a "spring-lock" anchor, is illustrated in FIGS. 10 and 11. In FIG.
10, the device 46e is shown in an undeployed state, and comprises a
driver 148 disposed within an anchor body 150. A suture return pin
152 is disposed within the body 150, in either a fixed or rotatable
fashion, as has been discussed in connection with previously
described embodiments, about which lengths of suture 34aand 34b are
disposed, as shown. The suture lengths 34aand 34b are threaded
through a spring 154, one end of which is secured to the anchor
body at an anchor point 156. The wire forming the spring 154 can be
of a number of different shapes, including round, square,
hexagonal, rectangular, and the like. A free end 157 of the spring
154 abuts a distal portion of the driver 148, as shown. In
operation, when it is desired to tension the suture 34, thus also
approximating the soft tissue 22 to the bone 24 (FIGS. 1A-1F), the
driver 148 is rotated in a clockwise direction, as shown by arrow
158. This action causes the free end 157 of the spring to move in a
clockwise direction as well, thus expanding the inside diameter of
the spring 154, thereby permitting axial movement of the suture
34a, 34b as desired.
[0078] Then, when it is desired to anchor the suture in place, the
driver 148 is retracted proximally, in the direction of arrow 160,
as shown in FIG. 11. This causes the spring to want to relax to its
normal state, thus moving in a counter-clockwise direction as shown
by arrow 162. As a result, the spring 154 wraps itself about the
suture lengths 34a, 34b to compress and lock them in place within
the spring.
[0079] Not illustrated, but contemplated within the scope of the
invention, is the inclusion of a compressible sleeve around which
the spring 154 may be wrapped, and through which the suture 34 may
be threaded. When the spring collapses, the sleeve also collapses
on the suture, thereby locking it in place.
[0080] Now, with reference to FIGS. 12 and 13, there is shown still
another suture anchor embodiment, wherein a plurality of stacked
leaf springs 164 are employed to lock a suture length 34 in place.
The leaf springs 164 may be made of any biocompatible material,
including stainless steel, absorbable or non-absorbable plastic
materials, and the like. In FIG. 12, the device 46f is shown in an
undeployed state, the leaf springs 164 being in a flat, stacked,
axially spaced configuration. Each spring 164 includes a pair of
apertures 166, 168, for accommodating the suture 34 therethrough.
The suture length 34 extends distally through the first set of
apertures 166, about a suture return pin 170, then proximally
through the second set of apertures 168. A mandrel 172 is pressed
distally against the proximal-most leaf spring 164 to maintain the
leaf springs 164 in the aforementioned flat configuration, which is
also the deformed state for the leaf springs. In this deformed
configuration, the suture 34 may be freely threaded through the
apertures 166, 168 of each leaf spring 164, and tensioned as
desired to approximate the soft tissue 22 to the bone 24.
[0081] When the tensioning step has been completed as desired, the
mandrel 172 is withdrawn proximally, thereby releasing the leaf
springs 164, so that they may return to their undeformed state, as
shown in FIG. 13. In this configuration, the suture 34 is trapped
and bound within the apertures 166 and 168, which have now assumed
an elliptical shape, and about the pin 170, thus functioning as a
suture anchor.
[0082] In FIGS. 14 and 15, there is shown another embodiment of a
suture anchor 46g, which is similar in many respects to the
embodiment of FIGS. 12 and 13. FIG. 14 illustrates the suture
anchor in an undeployed state, comprising a length of suture 34
which extends both distally and proximally through a stack of leaf
springs 164', in a manner similar to the embodiment of FIGS. 12 and
13, as well as about a suture return member 170'. A major
difference between this embodiment, and the embodiment of FIGS. 12
and 13, is that in this embodiment the leaf springs 164' are
undeformed in their flat state, as shown in FIG. 12. The materials
from which leaf springs 164' may be manufactured are similar to
those from which the leaf springs 164 in the embodiment of FIGS. 12
and 13 may be manufactured. The device 46g is inserted into the
bone cavity 40 (not shown in FIGS. 14 and 15) sufficiently distally
such that the mandrel 172' is disposed beneath the cortical bone
42. The proximal cap portion 174 of the mandrel 172' is rotated to
extend beyond the width of the cavity 40, and thus anchor the stack
of leaf springs 164' axially beneath the cortical bone layer. The
soft tissue 22 is then approximated to the adjacent bone 24 by
tensioning the suture 34 as desired, since it is freely movable
through the leaf spring stack in the undeployed state. Then, as
shown in FIG. 15, when the tensioning step is completed, the
mandrel 172' is moved distally, relative to the suture return
member 170', by pulling a wire running through the stack of leaf
springs 164' or other suitable method. A distal portion 176 of the
mandrel 172' comprises a wedge shape which impacts the leaf springs
164', causing them to deform into the folded configuration shown in
FIG. 15. This folding action causes a reduction in cross-section of
the apertures 166', 168' through which the suture length 34
extends, thereby locking the suture in place.
[0083] In FIG. 16, there is shown yet another embodiment of a
suture anchoring device 46h, which comprises a body 178, on which
is disposed a plurality of sleeves 180 which are adapted to extend
into adjacent cancellous bone (not shown), for anchoring the body
within the bone. A core 182 is disposed within the body 178. Three
fins 184 (two are shown) are disposed in an equally spaced fashion
about the circumference of the body 178, between the core 182 and
the inner surface of the body 178. Suture 34 is attached to soft
tissue 22, such as a rotator cuff tendon (see FIGS. 1A-1F), and
extends through the body 178, being wrapped about the core 182
along its length, as shown. One end of the suture 34 is attached to
a distal end of the core 182 at an anchor point 186.
[0084] In operation, a driver (not shown) having a hex head engages
a hexagonal aperture 188, and rotates the core 182, in order to
further wrap the suture 34 about the core, and to thus tension the
suture 34 and approximate the tendon 22 to adjacent bone (not
shown). When the suture 34 is tensioned as desired, the core is
rotationally locked in place, to thereby anchor the suture in
place. During the tensioning step, the fins 184 function to snag
the suture and to act as bearings for the core 182.
[0085] Another embodiment of a suture anchoring device 46i is shown
in FIGS. 17-20. The device comprises a first plate 190 and a second
plate 192, with the first plate 190 being disposed beneath the
second plate 192. In FIGS. 17 and 19, the device is shown in an
undeployed state. The plates 190 and 192 are disposed within a
hypotube 194. Welds 196 join the two plates. A length of suture 34
is threaded through the device 46i, as shown in FIG. 17, including
apertures 198, 200, and 202 in the plates 190 and 192,
respectively.
[0086] As shown in FIGS. 18 and 20, to deploy the device 46i and
anchor the suture 34, the upper plate 192 is retracted proximally,
as shown by arrow 204. In the presently preferred embodiment, when
a force in excess of 60 lb. is applied, the welds 196 fracture,
thereby separating the plates 190, 192, and creating a space 206
therebetween. The axial displacement of the upper plate 192
relative to the lower plate 190 creates a tortuous path through the
apertures 198, 200, and 202, as well as the space 206, through
which the suture 34 traverses, thereby anchoring the suture in
place.
[0087] Yet another suture anchoring device 46jis shown in FIGS.
21-24. In this embodiment, there is provided an outer tube 208
having a lumen 210, as shown in FIG. 21, in cross-section. The tube
208 is disposed in a blind hole 40 within bone, as discussed in
connection with previously disclosed embodiments. Suture lengths
34a, 34b are disposed through the lumen 210, as shown in FIG. 22,
for attaching soft tissue 22 to bone 24. As in prior embodiments,
each suture length extends distally through the lumen 210, about a
suture return member, such as a pin (not shown), disposed at a
distal end of the device 46j, and then extends proximally through
the lumen and out of a proximal end of the device 46j. FIG. 23
illustrates a next step in the inventive sequence, wherein a tube
212 having a split 214 therein is introduced into the lumen 210,
separating the proximally-extending legs of each suture length 34a,
34b from the distally-extending lengths of the same suture lengths.
The tube 212 is formed of a suitable deformable or elastomeric
biocompatible material. Then, once the suture 34a, 34b has been
suitably tensioned to approximate the soft tissue 22 to the bone
24, a tapered actuation pin 216 (FIG. 24) is introduced distally
into a lumen 218 of the split tube 212. Alternatively, the pin 216
could be pulled proximally through the lumen 218. This activity
causes the outer diameter of the tube 212 to expand, because of
separation at the split 214, as shown, thereby compressing, and
thus anchoring the suture lengths 34a, 34b in place, as shown in
FIG. 24.
[0088] Yet another embodiment of a suture anchoring device 46k is
illustrated in FIGS. 25-26. In this embodiment, a tube 220 having a
lumen 222 is disposed in a blind hole 40 within bone, as discussed
in connection with previously disclosed embodiments. Suture lengths
34a, 34b are disposed through the lumen 222, as shown in FIG. 25,
for attaching soft tissue 22 to bone 24. As in prior embodiments,
and particularly as in the embodiment of FIGS. 21 -24, each suture
length extends distally through the lumen 222, about a suture
return member, such as a pin (not shown), disposed at a distal end
of the device 46k, and then extends proximally through the lumen
and out of a proximal end of the device 46k. In this embodiment, a
spring coil 224 is disposed axially through the lumen 222, again as
shown in FIG. 25. Once the suture 34a, 34b has been tensioned as
desired during the medical procedure, an actuation pin 226 (FIG.
26), similar to actuation pin 216, and preferably including a
taper, is inserted through the spring coil 224, as shown, either
proximally or distally, in order to expand the outer diameter of
the spring coil 224, and thereby compress and anchor the sutures
34a, 34b in place.
[0089] Finally, another alternative suture anchoring embodiment 461
is illustrated in FIG. 27. This binding tapered thread anchor
comprises an anchor body 228 adapted for disposition within a bone
cavity 40, including bone anchor wings 230 for axially anchoring
the body 228 within said cavity, as discussed in connection with
prior embodiments. Suture lengths 34a, 34b extend distally through
a center portion of the body 228, and continue about a suture
return member or pin (not shown), extending proximally out of the
body 228. The portions of suture lengths 34aand 34b which extend
proximally out of the body 228 are not illustrated, for clarity.
The interior wall 232 of the body 228 includes threads 234, and is
tapered such that the interior diameter of the body 228 decreases
in a distal direction, as shown. A tapered plug 236, having
external threads 238 which complement the threads 234, and are
adapted for engagement therewith, is adapted for disposition within
the body 228, as shown in the figure. After the suture has been
appropriately tensioned, as discussed in connection with prior
embodiments, the plug 236 is threaded into the body 228, in order
to create a zig-zag shaped binding lock on the suture 34, by
forcing the suture ends 34a, 34b against the interior wall 232 of
the body 228, such that the suture ends 34a, 34b are forced into
the tortuous path created by the engaged threads 234, 238.
[0090] The apparatus and method of the present invention may be
embodied in other specific forms without departing from its spirit
or essential characteristics. The described embodiments are to be
considered in all respects only as illustrative and not
restrictive. The scope of the invention is, therefore, indicated by
the appended claims rather than by the foregoing description. All
changes which come within the meaning and range of equivalency of
the claims are to be embraced within their scope.
* * * * *