U.S. patent application number 14/965419 was filed with the patent office on 2016-06-16 for methods and devices for threading sutures.
The applicant listed for this patent is DePuy Mitek, LLC. Invention is credited to Gary McAlister, Mehmet Z. Sengun, David B. Spenciner, Gregory R. Whittaker.
Application Number | 20160166246 14/965419 |
Document ID | / |
Family ID | 49303711 |
Filed Date | 2016-06-16 |
United States Patent
Application |
20160166246 |
Kind Code |
A1 |
Sengun; Mehmet Z. ; et
al. |
June 16, 2016 |
Methods and Devices for Threading Sutures
Abstract
Methods and devices are provided for anchoring suture to bone.
In one embodiment, an elongate weave of fibers can be provided
having a first portion with a first pick count and a second portion
with a second pick count that is greater than the first pick count.
The first portion can have a cross-section that deforms in response
to a force that is applied thereto. The first portion can have a
collapsible diameter and can have a bending stiffness that is lower
than a bending stiffness of the second portion of the suture. The
first portion can also have a first pattern that is different than
a second pattern on the second portion of the suture. The first
portion can be threaded into a suture anchor such that it can be
doubled over upon itself. The present invention also provides
exemplary sutures and drivers that can be used with the various
methods and devices disclosed herein, or with other methods and
devices known in the art.
Inventors: |
Sengun; Mehmet Z.; (Canton,
MA) ; McAlister; Gary; (Franklin, MA) ;
Whittaker; Gregory R.; (Stoneham, MA) ; Spenciner;
David B.; (North Attleboro, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DePuy Mitek, LLC |
Raynham |
MA |
US |
|
|
Family ID: |
49303711 |
Appl. No.: |
14/965419 |
Filed: |
December 10, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13623467 |
Sep 20, 2012 |
9237888 |
|
|
14965419 |
|
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Current U.S.
Class: |
606/228 ;
606/232 |
Current CPC
Class: |
A61B 90/92 20160201;
A61B 2017/00004 20130101; A61B 17/0401 20130101; A61B 17/04
20130101; A61B 17/0485 20130101; A61B 2017/0414 20130101; D10B
2509/04 20130101; A61B 2017/0458 20130101; A61B 2017/06185
20130101; A61B 2017/0053 20130101; A61B 2017/0412 20130101; A61B
17/0482 20130101; A61B 2017/00526 20130101 |
International
Class: |
A61B 17/04 20060101
A61B017/04 |
Claims
1. A suture, comprising: a biocompatible elongate weave of fibers
having a first length with a first pick count and a second length
with a second pick count that is greater than the first pick count,
wherein the first length defines a first pattern and the second
length defines a second pattern that differs from the first
pattern, and wherein a cross-section of the first length is
configured to deform when a force is applied thereto.
2. The suture of claim 1, wherein the first length has a resting
outer diameter that is greater than or equal to an outer diameter
of the second length, and the first length is configured to
collapse in diameter when a force is applied thereto.
3. The suture of claim 2, wherein the collapsed outer diameter of
the first length is less than the outer diameter of the second
length.
4. The suture of claim 1, wherein the second length has a bending
stiffness that is greater than a bending stiffness of the first
length.
5. The suture of claim 1, wherein the elongate weave includes a
hollow lumen extending at least partially therethrough.
6. The suture of claim 1, wherein the first and second patterns
each comprise an uninterrupted series of repeating units.
7. The suture of claim 6, wherein the repeating unit on the first
pattern has a length that is greater than a length of the repeating
unit on the second pattern.
8. The suture of claim 1, wherein the weave of fibers includes at
least one strand having a first color and at least one additional
strand having a second color.
9. The suture of claim 1, wherein the first length comprises a
terminal end portion of the suture.
10. The suture of claim 1, wherein the pick count of the second
length is about 60 picks per inch.
11. A method for threading a suture into a suture anchor,
comprising threading a first portion of a suture into a cannulated
anchor such that the first portion of the suture is doubled over
upon itself, and such that a second portion of the suture extends
from the cannulated anchor, the first portion of the suture having
a pick count that is less than a pick count of the second portion
of the suture.
12. The method of claim 11, wherein the first portion of the suture
defines a first pattern extending therealong, and the second
portion of the suture defines a second pattern extending therealong
that differs from the first pattern such that first pattern
indicates a portion of the suture to be threaded into the
cannulated anchor as a double strand.
13. The method of claim 11, further comprising pulling the first
portion of the suture into the cannulated anchor with a threader
tab.
14. The method of claim 11, wherein the first portion of the suture
has a resting outer cross-section, the method further comprising
pulling the first portion of the suture through the cannulated
anchor such that the cross-section of the first portion of the
suture deforms.
15. The method of claim 11, wherein the suture is wrapped around a
suture-receiving member extending across an inner lumen of the
suture anchor such that the suture is coupled to the suture
anchor.
16. The method of claim 11, wherein the first portion comprises
first and second legs of the suture, and where the suture includes
a mid-portion between the first and second legs.
17. The method of claim 11, further comprising implanting the
suture anchor in bone and securing terminal ends of the suture such
that tissue attached to the suture is securely anchored to the
bone.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser.
No. 13/623,467 filed Sep. 20, 2012, and entitled "Methods and
Devices for Threading Sutures," which is hereby incorporated by
reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to sutures and to
methods and devices for threading sutures into suture anchors.
BACKGROUND OF THE INVENTION
[0003] The complete or partial detachment of ligaments, tendons
and/or other soft tissues from their associated bones within the
body are relatively commonplace injuries, particularly among
athletes. Such injuries are generally the result of excessive
stresses being placed on these tissues. By way of example, tissue
detachment may occur as the result of an accident such as a fall,
over-exertion during a work-related activity, during the course of
an athletic event, or in any one of many other situations and/or
activities. In the case of a partial detachment, the injury will
frequently heal itself, if given sufficient time and if care is
taken not to expose the injury to further undue stress. In the case
of complete detachment, however, surgery may be needed to re-attach
the soft tissue to its associated bone or bones.
[0004] Numerous devices are currently available to re-attach soft
tissue to bone. Examples of such currently-available devices
include screws, staples, suture anchors, and tacks. In soft tissue
re-attachment procedures utilizing screws, the detached soft tissue
is typically moved back into its original position over the bone.
Then the screw is screwed through the soft tissue and into the
bone, with the shank and head of the screw holding the soft tissue
to the bone. Similarly, in soft tissue re-attachment procedures
utilizing staples, the detached soft tissue is typically moved back
into its original position over the bone. Then the staple is driven
through the soft tissue and into the bone, with the legs and bridge
of the staple holding the soft tissue to the bone.
[0005] In soft tissue re-attachment procedures utilizing suture
anchors, an anchor-receiving hole is generally first drilled in the
bone at the desired point of tissue re-attachment. A suture anchor
is then deployed in the hole using an appropriate installation
tool. This effectively locks the suture, with soft tissue attached
thereto.
[0006] While suture anchors provide an effective,
minimally-invasive technique for soft tissue repair, it is
desirable to utilize an anchor having a small diameter so as to
avoid unnecessary trauma. The size of the anchor, however, can be
limited by the size of the suture. Typically, a single strand of
repair suture is folded and trailing ends of the suture are
attached to a threader loop, which is used to pull the folded
suture into the anchor. When a folded suture is used, the
cannulated portion of the anchor must typically be large enough to
accommodate at least four times the thickness of the repair suture.
This in turn restricts the ability to reduce the size of the
anchor.
[0007] Accordingly, there remains a need for improved methods and
devices for attaching soft tissue to bone.
SUMMARY OF THE INVENTION
[0008] Various surgical devices and methods are provided herein. In
one embodiment, a suture is provided that includes a biocompatible
weave of fibers having a first length with a first pick count and a
second length with a second pick count. The first length can have a
cross-section that is configured to deform when a force is applied
thereto. In some embodiments, the first length can have a resting
outer diameter that is greater than an outer diameter of the second
length. The first length can be configured to collapse in diameter
when a force is applied thereto. The first length can include a
terminal end portion of the suture. In some embodiments, the
elongate weave can include a hollow lumen extending at least
partially therethrough. The weave of fibers can also include
varying patterns along the length thereof, such as at least one
strand having a first color and at least one additional strand
having a second color that differs from the first color such that
the first length defines a first pattern and the second length
defines a second pattern that differs from the first pattern.
[0009] The suture can vary in a number of ways. The second length
can have a bending stiffness that is greater than a bending
stiffness of the first length. In some embodiments, the collapsed
outer diameter of the first length can be less than or
approximately equal to the outer diameter of the second length. In
some embodiments, the pick count of the second length can be about
60 picks per inch. In other aspects, the first and second patterns
can each include an uninterrupted series of repeating units. The
repeating unit on the first pattern can have a length that is
greater than a length of the repeating unit of the second
pattern.
[0010] A surgical kit is also provided and can include a
biocompatible elongate weave of fibers having a first length with a
first pick count and a second length with a second pick count that
is greater than the first pick count. The first length can have a
cross-section that can be configured to deform when a force is
applied thereto. The kit can also include a cannulated anchor
having an inner lumen configured to receive the weave of fibers. In
some embodiments the inner lumen can be configured to receive a
doubled over portion of the first length of the weave of fibers. In
some embodiments the surgical kit can include a threader tab
configured to pull the weave of fibers into the inner lumen of the
cannulated anchor. In some embodiments, the kit can also include at
least one additional biocompatible elongate weave of fibers.
[0011] Methods for threading a suture into a suture anchor are also
provided. In one embodiment, the method can include threading a
first portion of a suture into a cannulated anchor such that the
first portion of the suture is doubled over upon itself, and such
that a second portion of the suture extends from the cannulated
anchor. The first portion of the suture can have a pick count that
is less than a pick count of the second portion of the suture. In
certain aspects, the first portion of the suture can define a first
pattern extending therealong, and the second portion of the suture
can define a second pattern extending therealong that differs from
the first pattern such that the first portion indicates a portion
of the suture to be threaded into the cannulated anchor as a double
strand.
[0012] The surgical method can include a variety of modifications.
For example, the method can include pulling the first portion of
the suture into the cannulated anchor with a threader tab. The
first portion of the suture can have a resting cross-section, and
the method can further include pulling the first portion of the
suture through the cannulated anchor such that the cross-section of
the first portion of the suture deforms. The suture can be wrapped
around a suture-receiving member extending across an inner lumen of
the suture anchor such that the suture is coupled to the suture
anchor. In some embodiments, the first portion can include first
and second legs of the suture, where the suture includes a
mid-portion between the first and second legs. In some aspects, the
method can include implanting the suture anchor in bone and
securing the terminal ends of the suture such that tissue attached
to the suture is securely anchored to the bone.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The invention will be more fully understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0014] FIG. 1 is a perspective view of one embodiment of a suture
having first and second portions with different pick counts;
[0015] FIG. 2A is a cross-sectional view of the first portion of
the suture of FIG. 1 taken along line A-A;
[0016] FIG. 2B is a cross-sectional view of the second portion of
the suture of FIG. 1 taken along B-B;
[0017] FIG. 2C is a cross-sectional view of the first portion of
the suture of FIG. 1 in a tensioned state;
[0018] FIG. 2D is a cross-sectional view of an embodiment of a
suture with a hollow channel extending therethrough;
[0019] FIG. 3 is a perspective view of the second portion of the
suture of FIG. 1 doubled over;
[0020] FIG. 4 is a cross-sectional view of one embodiment of a
suture anchor;
[0021] FIG. 5A is a cross-sectional view of a doubled over first
portion of the suture of FIG. 1 and the suture anchor of FIG.
4;
[0022] FIG. 5B is a cross-sectional view of the doubled over first
portion of the suture partially threaded into the suture anchor of
FIG. 4;
[0023] FIG. 6 is a cross-sectional view of one suture threaded
through tissue and into a threader loop extending from the suture
anchor of FIG. 4;
[0024] FIG. 7 is a cross-sectional view of the suture of FIG. 6
partially threaded through the suture anchor;
[0025] FIG. 8 is a cross-sectional view of the suture of FIG. 7
fully threaded through the suture anchor;
[0026] FIG. 9A is a cross-sectional top view of the suture of FIG.
8 threaded through the anchor; and
[0027] FIG. 9B is an alternative cross-sectional top view of the
suture of FIG. 8 threaded through the anchor.
DETAILED DESCRIPTION OF THE INVENTION
[0028] Certain exemplary embodiments will now be described to
provide an overall understanding of the principles of the
structure, function, manufacture, and use of the devices and
methods disclosed herein. One or more examples of these embodiments
are illustrated in the accompanying drawings. Those of ordinary
skill in the art will understand that the devices and methods
specifically described herein and illustrated in the accompanying
drawings are non-limiting exemplary embodiments and that the scope
of the present invention is defined solely by the claims. The
features illustrated or described in connection with one exemplary
embodiment may be combined with the features of other embodiments.
Such modifications and variations are intended to be included
within the scope of the present invention.
[0029] Various devices and methods are provided for anchoring
suture to bone. In an exemplary embodiment, a suture is provided
and is formed from several fibers or filaments that are woven
together. In general, the suture can have distinct portions along a
length thereof that each have a specific pick count. The pick
count, or PPI, refers to the setting used during manufacture to
define the number of picks (i.e., the number of times the fibers
cross) per inch of material. The pick count can affect the
tightness or looseness of the weave, as well as the dimensions and
the mechanical properties of the suture. The mechanical properties
important for surgical applications include strength, fatigue,
resistance to abrasion, resistance to nicking, stiffness, and knot
holding capability. Therefore, the pick count is carefully chosen
to optimize these parameters. For example, a pick count that is too
high can lead to premature loosening of the knot, whereas a pick
count that is too low can cause the suture to be easily damaged by
surgical instruments. The pick count for ORTHOCORD.RTM. #2
(manufactured by DePuy Mitek), for example, is chosen to be around
60 PPI to deliver an overall optimized performance. However, 60 PPI
may not render the best results for the suture's ability to fit
into and around tight passages, for which a looser suture structure
provided by a lower pick count may be a better choice. Therefore,
it may be beneficial for a suture to have multiple portions with
different pick counts to independently address these conflicting
requirements.
[0030] In one embodiment, the suture can include a first length or
portion having a first pick count and a second length or portion
having a second pick count that is greater than the first pick
count. As a result of the smaller pick count of the first portion,
the fibers will be more loosely woven than the fibers of the second
portion. The first portion can thus be configured to deform or
collapse more easily when a force is applied to the suture, such as
an axial force, a compression force, a bending force, or a pulling
force, for example. The first portion can also be more flexible
than the second portion because of the looser weave given by the
lower pick count, and as a result the first portion can have a
bending stiffness that is lower than a bending stiffness of the
second portion. Such a configuration will allow the fibers of the
first portion to realign relative to one another when the first
portion is deformed. For example, the first portion can be folded
or bent, and the fibers will reposition at the bend to allow the
first portion to deform and change in cross-sectional shape. This
will allow the first portion to be more easily introduced into a
smaller diameter suture anchor, as compared to a folded portion of
suture having a high pick count that retains a relatively
circularly cross-sectional shape when bent. As mentioned above,
however, the tissue repair can be accomplished with the higher
pick-count portion of the suture, which is optimized for that
purpose. In some embodiments, the suture can have three or more
portions having differing pick counts. The suture can also include
tactile and/or visual indicators for distinguishing the different
portions. For example, some of the filaments in the suture can be
colored such that weaving the filaments creates a pattern of
repeating units on the suture. In certain aspects, the first
portion can have a first pattern that is different than a second
pattern on the second portion.
[0031] While the suture can be used in a variety of applications,
in one exemplary embodiment the suture is particularly useful with
bone anchors for soft tissue repair. As a result of the differing
pick counts along the length of the suture, the flexible low pick
count portion of the suture can allow for use with a cannulated
suture anchor having a small-diameter inner lumen. For example, the
first portion of the suture having the lower pick count can be
threaded into a suture anchor such that the second portion extends
from the suture anchor. In some embodiments, the first portion can
be doubled over upon itself. The doubled over portion can be passed
through a lumen of the anchor, passed around a suture-receiving
member, and passed back through the lumen of the anchor such that
four lengths of the suture extend through the lumen. In other
embodiments, a different number of lengths of the suture, such as
two, can extend through the lumen of the anchor. In some other
embodiments, eight lengths of suture may coexist in the lumen of
the anchor, especially while the sutures are being coupled to the
anchor. Where multiple lengths of suture extend through the anchor,
the flexible low pick count portion of the suture can be
particularly advantageous as it allows the lumen's diameter to
remain relatively small and yet still be capable of slidably
receiving the suture therein. The second high pick count portion of
the suture can optionally remain partially or entirely outside of
the anchor, and can couple to tissue to securely attach the tissue
to the suture anchor, and thus to bone. In some embodiments, a
threader tab can be used to pull the suture into the suture anchor.
The present invention also provides exemplary sutures that can be
used with the various methods and devices disclosed herein, or with
other methods and devices known in the art. A person skilled in the
art will appreciate that, while methods and devices are disclosed
herein for anchoring soft tissue to bone, the methods and devices
can be used in a variety of other medical procedures.
[0032] FIG. 1 illustrates one exemplary embodiment of a suture 10
with varied pick counts. The suture 10 is formed from an elongate
weave of fibers or filaments 11, and the suture 10 has first and
second terminal ends 10a, 10b and a length 1 extending therebetween
along a longitudinal axis L. The pick count can vary along the
length of the suture to define distinct portions that differ in
flexibility. The suture can have a number of different portions
along its length. As shown in FIG. 1, the suture 10 includes a
first portion 12 that has a pick count that is less than a pick
count of a second portion 14.
[0033] While the suture 10 shown in FIG. 1 is formed from sixteen
filaments 11, the suture can be formed from any number of
filaments. Preferably, the number of filaments in the suture is in
the range of 4 to 32, and more preferably in the range of 8 to 16
depending on the particular surgical procedure to be performed. The
diameter, material, and color of each filament can also vary.
Generally, each filament can be formed from a biocompatible
material that can be absorbable or non-absorbable. Suitable
materials include, but are not limited to, polyethylene, including
ultra-high molecular weight polyethylene, polyester, polypropylene,
PDS, PLA, PGA, and blends or mixtures of any of the preceding. A
suture can be formed from identical filaments, or alternatively,
the suture can be formed from filaments with varying diameters,
materials, and/or colors. FIG. 1 shows a suture 10 formed of
filaments 11 made of different materials and having different
colors. Variations in the number of filaments and in the properties
of the filaments can provide different patterns on the suture, as
discussed further below.
[0034] The filaments can be braided, twisted, or woven together in
a number of different configurations to form the suture. For ease
of reference, the phrases "weave" or "weave of fibers" will be used
to describe the suture regardless of whether the filaments are
woven, twisted, or braided together. The number of filaments, the
direction or orientation of each filament, and/or the pick count
can vary. A pick count or picks per inch (PPI) represents the
number of times the fibers cross for every inch of length of the
suture. A lower pick count will result in a suture having a
relatively loose weave, while a higher pick count will result in a
suture having a relatively tight weave. The pick count can vary
over the length of the suture. In one exemplary embodiment, as
shown in FIG. 1, the pick count of the first portion 12 can be
about 15 PPI and the pick count of the second portion 14 can be
about 60 PPI. A person skilled in the art will appreciate that the
pick count can vary. By way of non-limiting example, the pick count
can be in the range of about 10 PPI to 100 PPI, and more preferably
can be in the range of about 15 PPI to 60 PPI. The pick count can
be selected based on various factors, such as the type of filaments
used, and/or the type of surgical procedure to be performed. As
indicated above, the pick count can affect the tightness of the
weave and mechanical properties of the suture. As shown in FIG. 1,
for example, the first portion 12 of the suture 10 is more loosely
woven than the second portion 14 of the suture 10.
[0035] The pick count can also affect a cross-section or an average
outer diameter of the suture. Suture size is typically determined
by an average outer diameter of a cross-section of the suture,
according to standards determined by the United States Pharmacopeia
(USP). As shown in FIGS. 2A and 2B, a resting outer diameter
d.sub.R of the first length 12 with the lower pick count taken
along the line A-A of FIG. 1 can be greater than a resting outer
diameter d.sub.2 of the second length 14 that has a higher pick
count taken along the line B-B of FIG. 1. However, the resting
diameter d.sub.R of the first length 12 can include adjustable
spaces between the filaments 11. The adjustable spaces between the
filaments can be reduced or removed by various forces, such as
pulling the suture, compressing the suture, etc. For example, when
an axial pulling force P is applied to the suture 10 in the
direction shown in FIG. 1, the filaments 11 can align themselves
within the adjustable spaces such that the resting diameter d.sub.R
of the first portion, as shown in FIG. 2A, reduces to the collapsed
outer diameter d.sub.C of the first portion, as shown in FIG. 2C.
Alternatively, or in addition, the filaments can align themselves
such that a cross-section of the suture changes in shape. For
example, the filaments can align themselves such that a
cross-section of one or more lengths of the suture conforms to a
cross-sectional shape of a lumen that they may be in. The collapsed
outer diameter d.sub.C can be less than the outer diameter d.sub.2
of the second portion 14. The outer diameter d.sub.2 of the second
portion 14 can include spaces between the filaments, as well, but
given the higher pick count and thus tighter weave of the second
portion, application of an axial force to the second portion 14 may
have minimal to no impact on the diameter d.sub.2. In addition, the
second portion can have a stronger tendency to maintain its
cross-sectional shape and can be less conforming to a different
cross-sectional shape of a lumen that it may be in. As shown in
FIG. 2D, the suture can also optionally contain a hollow core 18
extending partially or fully therethrough. The core 18 or lumen can
be produced from the weave pattern used to form the suture, and the
size of the core 18 or lumen can vary as desired. While the sutures
in FIGS. 2A-D are depicted as having substantially round
cross-sections, it will be understood that the cross-section of the
suture can be any shape.
[0036] The diameters of the first and second portions can vary, and
preferably can be made to correspond with standard USP suture
sizes. For example, the first portion can correspond to a standard
suture, such as Ethibond.RTM. #0 manufactured by ETHICON, Inc., of
Somerville, N.J., and the second portion can correspond to
available high strength sutures, such as ORTHOCORD.RTM. #2
manufactured by DePuy Mitek. In an exemplary embodiment, the
sutures can have a diameter in the range of 0.2 mm to 0.7 mm. A
person skilled in the art will appreciate that the pick count, the
number of fibers, the size of the fibers, etc., can all be selected
to provide a suture having a desired diameter along various
portions thereof. By way of non-limiting example, a portion of a
suture having a pick count of 15 PPI can have a diameter in the
range of about 0.25 mm to 0.30 mm, whereas a portion of a suture
having a pick count of 60 PPI can have a diameter in the range of
about 0.45 mm to 0.65 mm.
[0037] The pick count can also affect the flexibility or a bending
stiffness of the suture. A lower pick count will result in a
reduced bending stiffness and an increased flexibility, as compared
to a portion of the suture having a higher pick count. This can
allow the suture to be folded and inserted into a small diameter
lumen of a suture anchor. In particular, loosely woven fibers can
more easily reposition upon bending to allow the suture to deform
in shape and/or size. This can result in a reduced cross-sectional
profile of the suture, thereby allowing the suture to be inserted
into a small diameter lumen. A suture having an increased pick
count, on the other hand, will have a higher bending stiffness and
thus is less likely to deform when folded. As a result, the suture
will assume a larger profile when folded, thus rendering insertion
into a smaller diameter anchor more difficult.
[0038] FIG. 3 illustrates the second portion 14 of suture 10,
showing the effect of an increased pick count and bending
stiffness. A person skilled in the art will appreciate that, while
FIG. 3 illustrates a suture having a circular cross-sectional
shape, bending of the suture can result in deformation of the
cross-sectional shape. The drawings are thus not intended to limit
the shape and/or profile of the suture. As shown in FIG. 3, when
folding a suture having a higher pick count, the increased bending
stiffness of the suture can provide little room for repositioning
of the fibers. As a result, the fibers are generally maintained in
a relatively tight woven configuration, thus preventing the suture
from achieving a true 180 degree bend. This can create a gap 19 at
the bend. The greater the bending stiffness of the suture, the
greater the size of the gap produced at the bend. The gap can
result in a diameter D.sub.2 at the bend that is greater than the
combined diameter 2d.sub.2 of two strands of the suture. This can
impact the ability to pull the suture into a cannulated suture
anchor. By providing a suture having a first portion 12 with a
lower pick count and thus lower bending stiffness, the first
portion 12 of the suture 10 can deform more easily when bent as
compared to the second portion 14 of the suture 10. In particular,
the spaces between the fibers of the first portion 12 can allow the
fibers to move and reposition relative to one another, thereby
allowing the cross-sectional shape of the suture to change. By way
of non-limiting example, the cross-sectional shape along a bend in
the first portion 12 of the suture 10 can change from a circular
shape to an ovular or oblong shape. This will result in a folded
portion having a smaller profile, thereby allowing the folded
portion to fit into a smaller diameter lumen of a suture anchor, as
compared to a folded portion of the second portion 14 of suture 10.
A person skilled in the art will appreciate that the diameter or
width of the suture at the fold may not necessarily change, but
that the ability of the fibers to move due to the loosely woven
configuration will facilitate insertion into a small diameter lumen
of a suture anchor.
[0039] While the suture 10 of FIG. 1 shows a first portion 12 with
a lower pick count and a second portion 14 with a higher pick
count, various other configurations of suture are possible. The
number and length of portions having different pick counts can vary
along the length of a suture. In some embodiments, the suture can
have more than two distinct portions. For example, a suture can
have first, second, third, and fourth sequential portions with
alternating pick counts. In particular, the first portion and the
third portion can have identical pick counts, and the second
portion and the fourth portion can have identical pick counts.
Alternatively, in some embodiments, a suture can have more than two
different pick counts. For example, the suture can include first,
second, third, and fourth portions each having a different pick
count. In addition, the pick count can be tailored to change
gradually along a length of the suture in almost any desired
pattern. Preferably, terminal end portions of a suture have
relatively lower pick counts such that the terminal end portions
can be more easily threaded into a suture anchor.
[0040] As mentioned above, varying pick counts can cause various
patterns in the suture. Each pattern can be formed by an
uninterrupted series of repeating units. For example, as shown in
FIG. 1, the first portion 12 having a first pick count can have a
first pattern formed by repeating units 212, and the second portion
14 having a second pick count can have a second pattern formed by
repeating units 214. The difference in pattern of the first and
second portions 12, 14 is a result of the change in pick count,
however, in addition to the pick count, the configuration of the
particular weave used to form the suture, and the diameter and
color of each filament can also cause variations in the
pattern.
[0041] The suture 10 can have a length 1 measured along
longitudinal axis L such that it can be threaded through various
components, such as a suture anchor. The length of the suture can
vary depending on various factors, such as the type of surgical
procedure being performed and/or the number of portions with varied
pick counts on the suture. For example, the length of the suture
can be in the range of about 300 mm to 1000 mm. In some
embodiments, the suture can be manufactured as a longer continuous
coil that can be cut into resulting separate smaller sutures as
needed. The continuous coil of suture can be cut such that the
resulting smaller sutures can have a desired pick count along
specific portions of the suture. For example, a continuous coil of
suture can be cut such that both terminal ends of the resulting
smaller sutures can have relatively lower pick counts. The suture
can also be used with a suture leader. Non-limiting examples of
suture leaders are discussed in U.S. patent application Ser. No.
13/623,290, filed on even date herewith and entitled "Suture
Leader," which is incorporated by reference in its entirety.
[0042] FIG. 4 illustrates a cut-away view of one exemplary
embodiment of a cannulated suture anchor 600 for anchoring tissue
to bone. As shown, the suture anchor 600 is in the form of a
generally elongate body having proximal and distal ends 600p, 600d
with an inner lumen 622 extending therethrough along a longitudinal
axis L.sub.A. At least one bone-engaging surface feature 624 can be
formed on at least a portion of an external surface thereof for
engaging bone. The suture anchor 600 can also include a
suture-receiving member 626 disposed within and extending across
the inner lumen 622 adjacent to the distal end 600d of the suture
anchor 600. The suture-receiving member 626 can be adapted to
receive one or more sutures therearound such that the suture(s) can
extend around the suture-receiving member 626 and trailing ends of
the suture(s) can extend through the inner lumen 622 and out of the
proximal end 600p of the suture anchor 600.
[0043] The body of the suture anchor 600 can have a variety of
configurations, shapes, and sizes. In an exemplary embodiment, the
anchor 600 is configured to be implanted within a bone tunnel
formed in bone, and more preferably it has a size and shape that
allows it to be fully engaged through the thickness of the cortical
bone. In the illustrated embodiment the body has a generally
elongate cylindrical shape with a blunt or rounded distal end 600d
to facilitate introduction of the anchor 600 into a bone tunnel.
The proximal end 600p of the body can be head-free, as the
cannulated configuration of the body can allow a driver to be
inserted into the inner lumen to drive the suture anchor into bone.
Alternatively, in some embodiments, the suture anchor can have a
head portion. As indicated above, the suture anchor 600 can also
include one or more bone-engaging surface features 624 formed
thereon and adapted to engage bone. While various surface features
can be used, such as teeth, ridges, protrusions, etc., in an
exemplary embodiment the body can include one or more threads
extending therearound.
[0044] The inner lumen 622 of the suture anchor 600 can have a
diameter d.sub.A that can vary depending on the type of procedure
being performed and the type and number of sutures being used. As
previously discussed, the lower pick count of the first portion 12
of the suture 10 can allow the fibers to reposition and the suture
to more easily deform along a bend. As shown in FIG. 5A, the lower
pick count and greater flexibility will allow the bend in the first
portion 12 of the suture 10 to be easily inserted into the inner
lumen 622 of the anchor 600. In other words, the bend in the first
portion 12 can compress and/or deform more easily so the first
portion 12 of the suture 10 can be loaded into the suture anchor
600. Once the first portion 12 of the suture 10 is loaded into the
suture anchor 600, it can be pulled further into the inner lumen
622 such that the attached second portion 14 of the suture 10 can
follow the first portion 12 into the suture anchor 600, as shown in
FIG. 5B. In this way, the second portion 14 can be loaded into the
suture anchor 600 without having to bend or fold the suture 10 at
the second portion 14. The inner lumen 622 can accommodate four
legs of the suture when the suture is fully threaded therethrough,
as shown below in FIGS. 8 and 9. In other embodiments, the diameter
of the inner lumen can be sized to accommodate multiple strands or
various types or sizes of suture, including varying pick counts and
bending stiffness.
[0045] As previously indicated, the suture anchor 600 can also
include a suture-receiving member formed therein. The
suture-receiving member 626 can have a variety of configurations,
but in an exemplary embodiment it is adapted to seat one or more
sutures that extend through the inner lumen 622 of the anchor 600
so as to couple the suture(s) to the anchor. As shown in FIG. 4,
the suture-receiving member 626 is in the form of a post that
extends transversely across the inner lumen 622 and between opposed
inner sidewalls 628, 630 of the suture anchor 600. The angular
orientation of the suture-receiving member 626 relative to a
longitudinal axis L.sub.A of the inner lumen 622 can vary, but in
an exemplary embodiment the suture-receiving member 626 extends
substantially perpendicular to the longitudinal axis L.sub.A of the
inner lumen 622. The location of the suture-receiving member 626
can also vary, but in an exemplary embodiment the suture-receiving
member 626 is positioned at or adjacent to the distal end 600d of
the suture anchor 600. In the embodiment shown in FIG. 4 the
suture-receiving member 626 is located just proximal to the
distal-most end 600d of the suture anchor 600 so as to form a
suture-seating groove in the distal-most end 600d of the suture
anchor 600. This recessed configuration of the suture-receiving
member 626 can allow a suture(s) disposed around the
suture-receiving member 626 to sit flush or sub-flush with the
distal end 600d of the suture anchor 600 such that the suture(s)
will not interfere with insertion of the suture anchor 600 into
bone. A person skilled in the art will appreciate that the
suture-receiving member can be integrally formed with the suture
anchor, i.e., the suture anchor and suture-receiving member can be
molded as a single unit or formed from a single piece of material,
or the suture-receiving member can be fixedly or removably mated to
the suture anchor. Additionally, the suture-receiving member can
have other configurations, such as an eyelet (not shown) that can
receive the suture therethrough. Non-limiting examples of suture
anchors and deploying suture anchors into bone are described in
further detail in U.S. application Ser. No. 11/555,545 entitled
"Cannulated Suture Anchor" filed Feb. 1, 2006, now U.S. Pat. No.
8,114,128, U.S. application Ser. No. 11/855,670 entitled "Dual
Thread Cannulated Suture Anchor" filed Sep. 14, 2007, U.S.
application Ser. No. 10/615,625 entitled "Bioabsorbable Suture
Anchor System For Use In Small Joints" filed Jun. 27, 2003, now
U.S. Pat. No. 8,133,257, U.S. patent application Ser. No.
13/623,258, filed on even date herewith and entitled "Anti-Backup
Suture Anchor," and U.S. patent application Ser. No. 13/623,449,
filed on even date herewith and entitled "Self-Cinching Suture
Anchors, Systems, and Methods," all of which are hereby
incorporated by reference in their entireties.
[0046] The devices described above can be used to perform a
surgical procedure for attaching tissue to bone, e.g. anterior
cruciate ligament (ACL) repair, rotator cuff repair, etc. In an
exemplary embodiment, a procedure including implantation of the
implant can be a minimally invasive procedure, but as will be
appreciated by a person skilled in the art, the implants discussed
herein also have application in open surgical instrumentation as
well as application in robotic-assisted surgery. Though reference
is made to the suture 10, the devices shown are exemplary and the
method can be performed with various other sutures.
[0047] As one skilled in the art will appreciate, the procedure
usually begins by preparing the patient for surgery and making one
or more appropriately sized incisions at a desired location. In a
minimally invasive procedure, one or more cannulas can be
positioned in the incisions to provide access to the surgical site.
One skilled in the art will also understand that one or more
viewing devices, e.g., scopes, can be placed in one of the
incisions to allow medical personnel to view the surgical site from
outside the body.
[0048] Once the patient is prepared for surgery, a length of suture
10 can be inserted into the patient's body and through tissue to be
surgically reattached to bone. When a combination suture and suture
leader is used, the leading end of the suture leader can be
inserted through the tissue directly using a tool, such as a
needle. The leader can be used to pull the suture coupled thereto
through the tissue. Alternatively, the suture can be threaded
through the tissue and then coupled to the suture leader, e.g., by
passing the leading end of the suture into the lumen in the
trailing end of the suture leader. One skilled in the art will
appreciate that the suture and/or leader can be passed through the
tissue using any known surgical technique, such as by mattress and
cinch loop methods. With the suture and leader so positioned, a
bore, bone hole, or bone tunnel, generally referred to herein as a
"bone hole," can be formed in bone of the patient. The bone hole
can be pre-formed, such as by using a drill, an awl, a punch
instrument, etc., as will be appreciated by a person skilled in the
art. Alternatively, the bone hole can be formed simultaneously with
advancement of a suture anchor into the bone and simultaneously
with threadable engagement of the anchor therewith, such as by
using a self-awling or self-tapping driver and/or self-awling or
self-tapping anchor. The bone hole can extend fully through
cortical bone to allow the suture anchor to be fully engaged
through the thickness of the cortical bone. The bone tunnel can
also extend into cancellous bone located underneath the cortical
bone. The suture anchor can be deployed in the bone hole before or
after suture leader is threaded or loaded onto the suture anchor.
With the suture and/or leader(s) threaded through tissue, the
terminal ends can extend outside of the body. The suture and the
leader can be threaded onto the anchor, either before or after the
anchor is implanted in bone.
[0049] With the suture extending through or around tissue, the
trailing ends can extend outside of the body and can be manipulated
by a user. In one embodiment, the suture can be threaded onto the
anchor while the anchor is positioned outside of the patient's
body. The suture can be threaded through the anchor in various ways
and using various tools known in the art, such as a threader loop.
For example, as shown in FIG. 6, a suture 100 having a first
portion 112 with a lower pick count a second portion 114 with a
greater pick count can be threaded through tissue T. The first
portion 112 can include opposite end portions of the suture 100,
which include trailing ends 100a, 100b. The suture 100 can then be
threaded through a loop portion 742 located on a trailing end 700b
of a threader loop 700 prior to threading the suture 100 through
the anchor 600. Preferably, the first portion 112 is threaded
through the threader loop 700 because the lower pick count and
lower bending stiffness can allow it to deform and/or compress at
the bend when bent around the loop portion 742 of the threader loop
700, as shown in FIG. 7, making the first portion 112 easier to
thread into the suture anchor 600 than the second portion 114 or a
standard high strength suture. When the threader loop 700 or other
threading tool is used, the threader loop 700 can optionally be
pre-disposed within the lumen/cannulated portion 622 of the anchor
600, as shown in FIG. 6. The threader loop 700 can be wrapped
around the suture-receiving member 626 and a leading end 700a of
the threader loop 700 can exit from the same opening of the suture
anchor 600 that it entered such that both the leading and trailing
ends 700a, 700b of the threader loop 700 extend from a proximal end
of the suture anchor 600, as shown in FIG. 6.
[0050] The leading end 700a of the threader loop 700 can be pulled
proximally with a force F such that the trailing end 700b is pulled
distally into the suture anchor 600 with the first portion 112 of
the suture 100 folded around the loop portion 742, as shown in FIG.
7. As the leading end 700a of the threader 700 is further pulled
proximally, the trailing end 700b, and thus the attached suture
100, are pulled around the suture-receiving member 626 and then
pulled proximally through the suture anchor 600. The axial force on
the suture produced by the pulling of the threader loop can cause a
diameter of the first portion of the suture to collapse and/or
deform such that it conforms to the confines of the lumen of the
anchor. The threader loop 742 can be further pulled proximally such
that the trailing end 700b exits the proximal end of the suture
anchor 600, pulling the trailing ends 100a, 100b and the first
portion 112 of the suture with it, as shown in FIG. 8. The first
portion 112 of the suture 100 can be pulled such that the second
portion 114 of the suture 100 is partially threaded through the
suture anchor 600, as shown in FIG. 8, or alternatively, the first
portion can be pulled such that the second portion is either not at
all threaded or fully threaded through the suture anchor. In other
embodiments, the threader can pass through the distal end of the
suture anchor, pulling the suture thereafter. In these embodiments,
the suture can be left extending from the distal end of the anchor,
or it can be threaded back through the anchor in a distal to
proximal direction. The first portion 112 of the suture can have a
length such that it can extend substantially through the inner
lumen 622 of the anchor 600, as shown, or in other embodiments the
first portion can extend partially through the lumen 622. FIG. 9A
shows a cross-section of the top view of the suture anchor 600 once
the suture 100 has been fully threaded therethrough. FIG. 9B shows
an alternative cross-section of the top view of the suture anchor
600 once the suture 100 has been fully threaded therethrough such
that the cross-sectional shape of the first portion 112 deformed.
While FIGS. 9A and 9B show the suture 100 fully threaded through
the suture anchor such that each of the first portion 112 and the
second portion 114 are partially threaded through the suture anchor
600, the suture can alternatively be fully threaded through the
anchor such that either the first portion 112 is entirely threaded
through the suture anchor or the second portion 114 is entirely
threaded through the suture anchor.
[0051] With the suture 100 threaded through the suture anchor 600,
the suture anchor 600 can be deployed into the bone using various
techniques. For example, the suture anchor 600 can be positioned on
a distal end of a driver (not shown), and the driver can be rotated
to force the suture anchor 600 through the bone, such as through
the bone tunnel previously described. The suture 100 can be
tensioned to draw the tissue toward the suture anchor 600 either
prior to, during, or subsequent to driving the suture anchor 600
into the bone. When the suture anchor 600 is fully seated in the
bone, it can extend at least through cortical bone or through
cortical bone and cancellous bone. After the suture 100 is
tensioned to pull the tissue toward the bone, trailing ends 100a,
100b of the suture 100 can be tied off or otherwise secured to
maintain contact between the tissue and the bone. Various methods
can be used to secure the suture, for example, a single or multiple
knots, a self-knotting suture, or a knotting element, as will be
appreciated by one of skill in the art. For example, the trailing
ends 100a, 100b of the suture 100 can be knotted together such that
tissue T attached to the suture 100 can be securely anchored to the
suture anchor 600, and thus to the bone.
[0052] As previously indicated, the suture anchors disclosed herein
can be configured for use with one or more sutures. The particular
quantity of sutures used with a suture anchor can depend on the
size of the suture anchor, and in particular on the diameter of the
inner lumen of the suture anchor.
[0053] Any combination of the devices described above can be
provided in a surgical kit. For example, the kit can include one or
more sutures having varied pick counts as described above. The kit
can include one or more suture anchors of various shapes and sizes,
depending on the type of procedure to be performed and the types of
sutures included. Alternatively, the kit can include suture anchors
of similar shapes and/or sizes that each have inner cannulas having
different diameters. The kit can also include a threader tab or any
other threading tools.
[0054] One skilled in the art will appreciate further features and
advantages of the invention based on the above-described
embodiments. Accordingly, the invention is not to be limited by
what has been particularly shown and described, except as indicated
by the appended claims. All publications and references cited
herein are expressly incorporated herein by reference in their
entirety.
* * * * *