Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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APPARATUS AND METHOD FOR MANIPULATING
AND ANCHORING TISSIJE
Technical Field
This invention relates to an apparatus and
method for manipulating and an~horing cartilage and
similar fibrous tissue within a joint.
Back~round Art
Conventional medical clamps have certain
disadvantages when used for manipulating cartilage or
other tissue within a joint during arthroscopic
surgery. Primarily, the clamps have a tendency to
slip off the cartilage. Additionally, the size of the
clamps in relation to the relatively small space
within the joint makes it difficult to maneuver other
surgical instrum~nts, such as a scalpel or
arthroscope, within the confined space of the joint.
Such clamps can also interfere with the view of the
inside of the joint a~forded by the arthroscope.
Since the clamps must be introduced into the joint
through an incision, they are limited in their range
of manipulation by the location of the incision. In
order to apply a desired directional traction to the
cartilage, it may be necessary to release the clamp
from the cartilage, reintroduce the clamp through
another incision, and reclamp the cartilage.
It is often necessary to repair torn fibrous
tissue, such as a ligament or tendon, or reattach such
tissue to bone. While in some instances it is
possible to insert two needles into the joint and then
thread both of them with a suture to form a loop to
reattach torn parts of fibrous tissue, that procedure
is undesirable because it is somplex and time-
consuming. The alternative of more radical arthrotomy
is also undesirable because of the increased amount o~
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trauma and resultant inreased morb:idity encountered
in the use of such a procedure.
As is explained in the fo:Llowing summary and
description, the present invention provides a
relatively compact and easy to use apparatus for
manipulatinq cartilage and other fibrous tissue, and
for anchorin~ the tissue to other tissue sr to bone.
Some technical references that may be of general
interest are as follow: Allen, U.S. Patent 3,699,969;
Shein, U.S. Patent 3,527,223; Woo, U.S. Patent
3,943,932; Almen, U.S. Patent 3,500,820; Johnson et
al., U.S. Patent 3,871,368; and Smith, U.S. Patent
4,243,037. None of these references discloses a
method or apparatus suitable for manipulating fibrous
tissue during arthroscopic surgery~ or for effectively
reattaching fibrous tissue to bone or to other fibrous
tissue.
Summary of the Invention
The aforementioned problems associated with
use of conventional medical clamps for manipulating
tissue are overcome by the present invention, which
provides an apparatus and an associated method for
manipulatîng and anchoring tissue during arthroscopic
surgery. The apparatus provides adequate fixation of
the tissue duriny such surgery and minimally
interferes with the use of other instruments within
the joint.
The apparatus particularly comprises an
elongated anchor member having a suture attached
proximate the midpoint of its length. The anchor
member is inserted through the tissue with the suture
extending therefrom to provide a mechanism for
manipulating the tissue within the joint. The end
faces of the anchor member may be slanted to
facilitate movement of the anchor member through the
tissue.
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The preferred means of inserting the anchor
member includes a hollow n edle having a sharp tip and
an open butt. A hollow tube o~ equal or greater
length than the needle slides within the needle. A
limiting mechanism is provided at the butt of the
needle and at the corresponding portion of the hollow
tube to selectively position the tube within the
needle so that the tube does not extend outwardly
beyond the tip of the needle.
The anchor member is located within the tip
of the hollow needle in either a de~ormed U shape, or
in its normal, substantially straight shape. The
suture extends from the anchor member through the bore
of the tube.
A removable shield fits over the tip of the
needle to prevent the sharp tip from cutting the
suture or the anchor member during the process of
inserting the anchor member into the hollow needle.
With the anchor member located within the
tip of the needle, the needle tip is inserted into a
joint duriny a surgical procedure. The needle tip
pierces the tissue to be anchored and passes
substantially through the tissue. The limiting
mechanism is manipulated so that the tube may be
pushed forward to the tip of the needle, thereby
expelling the anchor ~ember from the tip of the needle
into or behind the piece of tissue to be anchored. As
the anchor member is sxpelled from the tip of the
needle it assumes an orientation generally
perpendicular to the length of the suture. The needle
and tube ars then removed from the joint, leaving the
suture extending through the tissue and out of the
joint. The tissue is manîpulated by the application
of tension on the suture.
If it is desirable to push the tissue, the
suture may be rethreaded or left threaded in tha tube
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and the tissue may then be securely held between the
tube and the anchor member hy applying tension to the
suture. If it is desirable to control the tissue from
a different angle, or through a different incision, a
hook-ended instrument may be passed through another
incision to hook the suture and pull the tissue. It
will be apparent that moving the tissue in this manner
is possible without detachiny the anchor member from
the tissue. If necessary, the tissue may be removed
from the joint by tension on the suture once the
tissue has been surgically freed from the joint.
It is o~ten desirable to permanently
reattach to bone fibrous tissue, such as tendons or
ligaments. An alternative embodiment of a tissue
anchoring apparatus is provided for that purpose.
More particularly, the apparatus of this embodiment
includes a deformable anchor member that has a base
and at least two legs. Each leg is attached to the
base and extends therefrom to terminate in an outer
end. A suture is attached to the base of the anchor
member. The anchor member is formed of resilient
material for urging the anchor member into a relaxed
position wherein the ends of the legs are spaced apart
a maximum distance. The anchor member is deformable
into a deformed position wherein the ends of the legs
are spaced apart a minimum distance that is less than
the maximum distance.
While in the deformed position, the anchor
member is insertable into a hole that i~ drilled into
the bone at the location the tissue is to be attached
to the bone. The hole has a diameter thak is less
than the maximum distance between the ends o~ the
anchor member legs. Consequently, upon insertion o~
the anchor member into the hole, the ends of the
anchor member legs bear upon the bone within the hole,
and the suture extends from the hole. Whenever
tension is applied to the suture, the ends of the legs
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dig into the bone and resist removal of the anchor
member from the hole.
~ith the anchor member anchored in the hole,
the suture is available for securinq the tissue to the
bone. One way of using the suture l:o secure the
tissue to the ~one is to attach a retainer to the
suture for pressing the tissue against the bone. The
retainer includes resilient suture-engaging edges and
corners, and is slidable along the suture in one
direction, but grips the suture to resist sliding in
the opposite direction. The retainer thereby holds
tissue against the bone during healing so that the
tissue will properly reattach to the bone.
To avoid prolonged irritation of surrounding
tissues, the anchor member, suture, and retainer of
the present invention may be made of material that is
gradually absorbable by the body.
The foregoing and other features of the
invention will be more readily understood upon
consideration of the following detailed description of
the invention, taken in conjunction with the
accompanying drawings.
Brief Description of the Drawinqs
Fig. 1 is an elevational view of an
apparatus for manipulating and anchoring tissue
according to the present invention, with a portion of
the apparatus sectionally cut away.
Fig. 2 is a sectional elevational view of
the apparatus shown in Fig. 1, illustrating the manner
of deformably lodging an anchor member within the tip
of a hollow needle.
Fig. 3 is a ~ragmentary, sectional
elevational view of the apparatus of Fig. 1, showing
the apparatus piercing cartilage~
Fig. 4 is a fragmentary, sectional
elevational view of the apparatus of Fig. 1,
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illustrating the manner of expelling ~he anchor member
between cartilage and bone.
Fig. 5 is a sectional elevational view of
the apparatus of Fig. 1, showiny cartilage ~ecured by
the anchor member and suture components of the
apparatusO
Fig. 6 is an enlarged perspective view of
the anchor member and suture, showing the normal and
deformed configuration of the anchor member.
Fig. 7 is a foreshortPned perspective view
of a hook-ended instrument usable with the apparatus
o~ Fig. 1.
Fig. 8 is a sectional elevational view of an
apparatus for manipulating and anchoring tissue,
illu~trating an alternative manner of lodging the
anchor member within the tip of the needle.
Fig. 9 is a sectional elevational view of
the apparatus shown in Fig. 8, illustrating expulsion
of the anchor member from the tip of the needle.
Fig. 10 is a perspective view of the inner
surface and an edge o~ a retainer used in association
; with the suture and the anchor member for securing
tissue to bone or to other tissue.
Fig. 11 is a perspective view of the outer
surface and an edge of the retainer shown in Fig. 10.
Fig. 12 is a perspective view of an
alternative retainer.
Fig. 13 illustrates a portion of a joint in
which the anchor member, suture, and retainer are used
to connect and retain a piece of cartilage in position
against another piece of cartilage ~rom which it had
been torn.
Fig. 14 is a sectional view taken along line
14-14 of Fig. 13.
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Fig. 15 is a side elevational view, partly
in section, of an anchor member and suture that can be
anchore.d to a bone.
Fig. 16 is a sectional elevational view of
the anchor member and suture of Fig. 15, positioned
within the preferred mechanism for inserting the
anchor member into a hole in a bone.
Fig. 17 is a sectional elevational ~iew
showing the anchor me~ber of Fig. 16 anchored within a
hole in a bone and used, in conjunction with the
suture and a retainer, to hold tissue against the
bone.
Fig. 18 is a sectional elevational view
; showing an alternative method of using an anchor
member and suture to hold tissue against the bone.
: Fig. 19 is a side cross-sectional view o. an
alternative embodiment of an anchor member that has a
hole formed therethrough to permit a suture to be
~;~ looped through it.
Fig. 20 is a cross-sectional view of another
alternative embodiment of an anchor member that can be
anchored to a bone.
Fig. 21 is a top view of the anchor member
of Fig. 20.
Description
One preferred embodiment of the present
invention, shown assembled in Figs. 1 and 2, provides
a resiliently de~ormable anchor member 10, which is
attached to a suture 12 and adapted to ~it deformably
within the tip 26 o~ a hollow needle 14. A hollow
tube 16, also adapted to fit within the needle 14, is
used to expel the anchor member from the tip 26 of the
needle after the needle has pierced a piece o~ fibrous
tissue, such as the cartilage 18, as shown in Figs~ 3
~nd 4. Once expelled between the cartilage 18 and
bone 38, the anchor member resiliently resumes its
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normal shape, as shown in Fig. 5. The anchor member
of the invention might also be used to secure ligament
or tendon, as will be described hereinafter, and the
term tissu~ will be broadly used herein to encompass
cartilage, tendons, ligaments and s:imilar tissue.
The anchor member 10, shown in perspective
view in Fig. 6, is an elongated cylindrical member.
The anchor member 10 has end faces ;20 and 22 at the
respectiYe extremities thereof. The end faces 20 and
22 are slanted relative to the longitudinal axis of
the anchor member and preferably lie in respective
planes that intersect one another. The suture 12 is
attached to the anchor member 10 at a location 24
between the end faces 20 and 22. The suture 12 may be
attached to the anchor member 10 during formation of
the anchor member.
The anchor member 10 is preferably comprised
of a resilient material such as a plastic. As a
result, the anchor member is capable of being deformed
from its relaxed, straight shape into a U-shape as
shown in broken line in Fig. 6. ~lthough the anchor
member is shown to have a circular cro~ section,
other cross-sectional shapes could be utilized without
departing from the principles of this invention.
The anchor member 10 is formed with
sufficient rigidity to cause it to resist deformation
under moderate pressure, but not so rigid as to
prohibit the U-shaped deformation when the anchor
member is lodged within the needle as shown in Figs. 2
and 3. The material comprising the anchor member has
sufficient elasticity to restore the anchor member
substantially to its relaxed, straight con~iguration
shown in Figs. 1, 4, 5 and 6O
The needle 14 shown in Figs. 1 and 2 has a
hollow cylindrical shape with a sharp-edged open tip
26, an open butt 27, and a bore extending
longitudinally therethrough from the tip 26 to the
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butt 27~ The sharp tip 26 is beveled to create a
sharp edge at its outer circumference and is thereby
adapted to pierce and penetrate tissue.
Alternatively, the sharp tip 26 could be beveled to
create a sharp edge at its inner circumference.
An annular collar 28, which includes an open
keyway 30 formed therein, encircles the butt of the
needle. The keyway extends a short distance toward
the needle tip through the cylindrical wall of the
ne~dle as shown in Fig. 2.
The hollow tube 16, which is at least as
long as the needle 14, and has an elongate cylindrical
shape with an open tip 17 and an open butt 19, is
adapted to slide within the hollow needle. The tube
16 has an interior bore diameter large ~nough to
receive the suture 12 therethrough so that the free
end 13 of the suture extends from the open butt 19 of
the tube. The tube 16 has an annular flange 32
encircling the butt 19 thereof to prevent the tube,
when pushed toward the needle tip 26, from protruding
more than a predetermined distance beyond the tip.
The tube is preferably such a length that when the
flange 32 is positioned immediately adjacent the
collar 28, the tip 17 of the tube is proximate the
needle tip 26, as shown in Fig. 4.
A limiting mechanism for controlling
movement of the tube 16 is provided in the form of a
key 34 that is mounted on the outer cylindrical wall
of the tube 16. The key 34 is adapted to mate with
the keyway 30 associated with the needle 14. The key
34 will prevent the tip 17 of the tube 16 from moving
proximal to the tip 26 of the needle 1~ unless the key
34 iB aligned with the keyway 30. This alignment is
accomplished by rotation of the tube 16 within the
needle 14. If the tube 16 is of the aforementioned
pre~erred length, the key 34 should be located close
enough to the tip 17 of the tube 16 to permit the
anchor member lO to be ~ully drawn into the needle tip
26 when the tube is positioned inside the needle with
the key and ke~way out of alignment, as shown in
Figs. 2 and 3. As will be apparentV the keyway 30
should be of su~ficient length to a:Llow the flange 32
to contact the collar 28 when the key 34 is positioned
in the keyway 30. It should be recognized that, while
the aforedescribed key and keyway arrangement is
believed to be parti.cularly suitable, other mechanisms
for limiting the movement o~ the tube 16 within the
needle 14 could be utllized without departing from the
principles of this invention.
As shown in Figs. 1 and 2, a shield 36
having a generally cylindrical shape with open ends is
adapted to fit removably on the sharp needle tip 26.
The inner walls of the shield have three distinct
sections: an upper section 29, an intermediate section
31, and a lower section 33. The upper section 29 is
cylindrical and has an inner diameter substantially
equal to the outer diameter of the needle tip 26 so as
to permit the shield to be mounted over the tip 260
The intermediate section 31 is cylindrical and has an
inner diameter slightly smaller than the outer
diameter of the needle tip 26, to shield the anchor
member from the sharp edge of the needle tip 26. The
lower section 33 has a bell-like flared shape to
encourage appropriate deformation o~ the anchor member
10 as it is drawn into the ne~dle tip 26 as shown in
Fig. 2.
Prior to use, the apparatus is firs~
assembled as shown in Figs, 1 and 2, the shield 36
being mounted upon the tip ~6 prior to the suture 12
being threaded through the tube 16 so that the free
end 13 protrudes out the butt end 19 of the tube.
Tension on the free end 13 of the suture 12 will pull
the anchor member 10 into the needle tip 26 as shown
in Fig. 2, the inner sur~ace of the bell-shapecl lower
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section 33 o~ the shield guiding the anchor member
into the appropriate U shape, the anchor member being
protected from the sharp tip by the shield 36.
The tube 16 is axially positioned within the
needle with the key 34 abutting the collar 28 so that
there is appropriate space for the anchor member to
lodge deformably within the needle tip 26.
Positioning the tube 16 within the needle as shown in
~ Figs. 1 and 2 is not necessary prior to introducing
,~ 10 the ~ree end 13 of the suture 12 into and through the
bore of the needle 14, but having the tube so
positioned when the anchor member 10 is drawn into the
tip 26 is helpful to ensure that the anchor member 10
is not positioned an unnecessary distance from the
needle tip 26. Once the anchor member 10 is
deformably lodged in the tip 26 r the shield 36 may be
removed.
The assembled apparatus may then be
introduced into the joint o~ a patient, either through
an incision or by using the needle tip 26 to pierce
the skin and surrounding tissue. The tip 26 of the
needle 14 is thereafter used to pierce the cartilage
; 18 which is to be manipulated or anchored, as shown in
Fig. 3.
Once the tip 26 has pierced the cartilage
18, the tube 16 may be axially rotated within the
needle 14 so that the key 34 aligns with the keyway
30O The tube 16 may then be pushed toward the tip 26
of the needle 14, the key 34 entering the keyway 30,
and the tip 17 of the tube 16 expelling the anchor
member 10 from the needle tip 26 as shown in Fig. 4.
As the anchor member 10 is pushed from the needle tip
26, it resumes its no~mal elongated shape. Where the
cartilage 18 is very near bone 38, the slanted end
faces 20, 22 of the anchor member facilitate movement
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12
of the longitudinal extremi~ies of the anchor member
through the space ~0 between the bone 38 and cartilage
18~
Once the anchor memb~-r 10 has generally
resumed its normal elongate shape behind the cartilage
18, the needle 14 and the tube 16 may be withdrawn
from the joint, allowing the cartilage 18 to partially
collapse around the anchor member 10 and sutur~ 12 as
shown in Fig. 5. The suture 12 is now anchored to the
cartilage 18, and the cartilage may be securely held
and manipulated by tension on the suture 1~ to
facilitate further surgical procedures on and around
th~ cartilag~.
The relatively small size of the ~uture 12
allows virtually unobstructed vision of the interior
of the joint through an arthroscope, and also permits
the insertion of other surgical instruments, such as
an arthroscope or scalpel, through the same incision
as the suture. Due to the flexibility of the suture
12, tension may be applied from many directions as
dictated by the needs of the surgical process.
Further control of the cartilage 18 is available by
rethrea~ing the suture 12 through the tube 16 and
applying tension to the suture, thereby effectively
: 25 clamping the cartilage 18 between the anchor member 10
and the tip 17 of the tube 16, and allowing the
cartilage to be pushed, rather than pulled, into a
desired position~
A hook-ended instrument 42~ shown in Fig. 7,
may be used to achieve even greater maneuverability of
the anchored cartilage 18 by introducing the
instrument 42 into the joint through a separate
incision, capturing the suture 12 in the hooked end of
the in.~trument, and drawing the suture 12 out of the
joint through such other incision. The cartilage may
then be manipulated and controlled in the manner
described above, through a different incision, without
detaching the anchor member 10 from the anchored
cartilage 18.
If necessary, the anchoreel cartilage 18 may
be surgically freed, and removed ~rom the joint by
tension on the suture 12.
Referring now to Figs. 8 and 9, an anchor
member 50, which is similax to the anchor me~ber 10
described above, has fixedly attaGhed thereto a suture
52. The anchor member 50 .is held within the tip 53 of
a hollow needle 54, ahead of the tip 56 o~ a hollow
tube 55. The edge of the hollow needle 54 at the tip
53 is formed in a plane that is slanted relative to
the longitudinal axis of the needle, thereby to form a
sharp leadiny edge 51 for piercing tissue. The free
end 57 of the suture 52 extends from the hollow tube
:` 55.
As shown in FigsO 8 and 9, the anchor member
50 may be used in essentially the same fashion as is
the anchor member 10, with the hollow needle 54
piercing a piece of fibrous tissue, such as cartilage
60. The anchor member 50 is expelled from the tip 53
of the hollow needle 54 as khe hollow tube 55 is slid
toward the tip 53 of the hollow needle 54. The anchor
member 50 thereafter assumes a position between the
cartilage 60 and a bone 62, where it extends generally
perpendicular to the suture 52. The slanted end faces
64, 65 of the anchor member 50 assist in directing the
anchor member 50 to this position. Once the anchor
member 50 has been expelled ~rom the needle 54, the
suture 52 is pulled outwardly to move the anchor
member 50 to the position shown in broken line in
Fig. 9, where it extends laterally along the lower
surface o~ the cartilage 60.
It is not~worthy that the anchor member 50
depicted in Figs. 8 and 9 may be formed of
substantially rigid material. A rigid anchor member
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14
can be inserted into the space between the cartilage
and bone by moving the needle 54 so that it is
inclined to the bone surface and then expelling the
anchor member from the naedle.
A rigid anchor member may be lodged within
cartilage or other tissue (i.e., as opposed to being
inserted between cartilage and bone~ hy expelling the
anchor member substantially straight into the tissue
and pulling on the suture~ Because the suture is
attac~ed between the ends of the anchor member,
tension on the suture tends to rotate the anchor
member into a position substantially perpendicular to
the suture, thereby causing the anchor member to
b~come firmly lodged within the tissue. In this
regard, rotational movement of the anchor member 50
into a position substantially perpendicular to the
suture 52 most readily occurs when the end face 65
that last enters the tissua is slanted so that a force
applied perpendicular to that surface (that forcP
being a component of the reaction force of the tissue
against the surface 65 as tension is applied to the
suture of the expelled anchor member) tends to move
that face 6~ of the anchor member 50 away from the
~uture 52. This preferred slanting of the end face 65
i~ shown in Figs. 8 and 9.
Referring now to Figs. 10-14, retainer
devices 68 and 69, each having a pair of generally
parallel surfaces, are made of resilient material and
have slits 70 and 72, respectively, which intersect
near the central points of the parallel surfaces,
de~ining pointed corner flaps 71 and 73, respectively.
The retainers 68 and 69 are preferably circular
because the circular shape may reduce the possibility
o~ irritation of surrounding ti~sue. It will be
understood, however, that thi~ shap~ i5 a matter of
choice and that other shapes would also be acceptable.
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~aised points 74 are provided on the inner
surface of the retainer 68 to bear against tissue, and
to assist in immobilizing the tissule while the anchor
member i5 in use. In many instance~s, however, the
raised points 74 will not be required and a flat inner
~urface will suffice. The following discussion of
retainer use is directed to the anchor member 50 of
Fig. 8; however, it is understood that the discussion
applles to all embodiments of the anchor member
described herein.
The retainer 68 (or retainer 69) may be used
in conjunction with the anchor member 50 by inserting
the free end 57 of the suture through the retainer at
the intersection of the slits 70 after the hollow
needle and hollow tube have been withdrawn from around
the suture. When the suture 52 is inserted through
the retainer 68, the flaps 71 that are defined between
adjacent slits 70 are resiliently deformed toward the
direction of movement of the suture therethrough.
Thereafter, the flaps wedge against the suture 52 and
resist withdrawal of the suture through the slits. By
applying tension to the suture 52 (see Figs. 13 and
14) and urging the retainer 68 along the suture to the
surface of cartilage 7~ from which the suture extends,
the retainer may be used to maintain tension in the
suture, thereby holding a loose piece of cartilage 76
against the stable piece of cartilage 78 from which
the loose piece of cartilage 76 had been torn or
fractured.
The anchor member 50, suture 52~ and
retainer 68 may be left permanently in the joint to
retain the torn cartilage 76 in its proper location
against the stable cartilage 78, with the retainer 68
resting against the outside of the stable cartilage
78, between the surface of the stable cartilage 78 and
muscle tissue 79 adjacent thereto.
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It is no~eworthy that in many instances the
needle 54 may be inserted into a joint from opposing
directions. For example, the anchor member 50 was
deposited in the position shown in Figs. 13 and 14 by
a needle that penetrated the muscle tis~ue 79. The
needle could have been inserted from the opposing side
of the joint (and not through muscle tissue 79) to
deposit the anchor m~mber 50 in the position occupied
by the retainer 68 in Figs. 13 and :L4. Accordingly,
the positions of the anchor member 50 and the retainer
68 would be reversed from those shown in Figs. 13 and
14, but the loose cartilage 76 would still be held
against the secure cartilage 78. One reason for
inserting the needle from the opposing side of the
joint, as just explained, would be to avoid damaging
any nerves or blood vessels that are present in the
region of the muscle tissue 79.
To prevent prolonged irritation o~ the
surrounding tissue by the presence of the anchor
memb~r 50 and retainer 68, it is particularly
desirable to ~orm the anchor member and retainer sf
material that can be gradually absorbed by the body of
the patient as healing occurs. Resilient, synthetic
materials that are gradually absorbable by the body
are known for use in sutures and are desirable as
materials for the anchor membar and retainers of the
present invention. One such material is an absorbable
polymer known as poly-diaxanone (PDS3, which is
available from Ethicon, Inc., of Summerville, New
Jersey.
Re~erring now to Figs. 15-17, an anchor
member 80 is particularly adapted for use in anchoring
a sutur2 82 to bone 96 so that the suture 82 may be
used to reattach tissue 98 to the bone. The anchor
member 80 i5 generally bullet shaped having a rounded
convex base 84 with two attached legs 86 extending
~rom the base. The outer ends 85 of the legs are
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tapered and terminate in a sharp outer ed~es 87. The
anchor member 80 is formed of resilient material, and
whenever the anchor member is in its relaxed state
(Fig. 15), the legs 86 diverge outwardly so that the
outer edges 87 of the legs are spaced apart a maximum
distance D. One e~d of a suture 82 is embedded
within, or otherwise attached to, the base 84 of the
anchor mem~er 80. Suture 82 extends outwardly from
the base 84 between the legs 86.
Preferably, ~he outer surface of the anchor
member 80 carries a plurality of barbs 88. The barbs
88 point outwardly, and away from the rounded convex
base 84. As a result, the exposed sharp point of each
barb 88 is directed generally toward the direction in
which the suture 82 extends away from the base 84 of
the anchor member 80.
As shown in Fig. 16, the anchor member 80 is
inserted within the tip 93 of a hollow needle 90 ahead
of the tip 91 o~ a tube 92 that is used to expel the
anchor member 80 from the needle. The suture 82
extends through the bore of the tube 92.
The anchor member 80 and the bore of the
needle ~0 are sized so that the anchor member is in a
deformed position whenever it is lodged within the tip
93 of the needle. In the deformed position, the legs
86 of the anchor member are pressed together with the
outer edges 87 of the legs being spaced apaxt a
minimum distance d corresponding to the needle bore
diameter. This distance d is less than the maximum
distance D between the outer edges 87 as measured when
the anchor member is in the relaxed position (Fig.
15).
As noted, the anchor member 80 is foxmed of
resilient material. Consequently, whenever the anchor
member 80 is expelled from the needle 90, the
intrinsic resilience of the anchor member urge~ it
into the relaxed position. As will now be explained,
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the tendency o~ the anchor member 8Q to move from the
deformed into the relaxed position provides a simple
mechanism for anchoring the anchor member 80 in bone
so that, in conjunction with the attached suture,
there i9 provided a means for reattaching tissue to
the bone to promote healing.
More particularly, with ref~rence to Fig.
17, a hole 100 is drilled into the hone 96 in the
region where the tissue 98 is to be reattached to the
bone. The hole diameter is less than the maximum
distance D between the outer edges 37 of the anchor
member, but greater than or equal to the bore diameter
of the needle 90. With the anchor member 80 within
the tip 93 of the needle 90, the tissue 98 is pierced
by the needle in a manner as described earlier. The
tip 93 of the needle is forced through the tissue 98
and then aligned with the hole 100. Next, the anchor
member 80 is expelled from the needle into the hole
100 by sliding the tube 92 toward th~ tip 93 of the
needle 90 as described earlier with respect to Figs.
3-5.
Once expelled from the needle 90 into the
hole 100, the resilience of the anchor member 80 urges
the outer edges 87 of th~ legs 86 to bear upon the
bone within the hole 100. With the outer edges 87 of
the leys bearing upon the bone, any tension applied to
the suture 82 causes the sharp edges 87 to dig into
the bone to secure the anchor member within the hole.
~he barbs 88 also dig into the bone to supplement the
anchoring effect of the legs 86.
Preferably, the anchor member 80 is sized so
that when it is positioned within the hole 100, the
outer edges 87 o~ the legs 86 are beneath a relatively
dense bone layer 97 that is located at the surface of
; 35 the bone 96, and is known as the cortical layer 97.
As a result, tenslon in the suture (in conjunction
with the intrinsic resilient force of the anchor
~3~2~
19
member 80 that forces the leg edges 87 apart) tends to
lodge the edges 87 of the anchor me~ber legs beneath
the cortica] layer 97, rendering the anchor member
substantially irremorable from the 'hole 100.
As shown in Fig. 17, a retainer 68 t as
described earlier, may be employed with the suture 82
to secure the tissue 98 to the bone 96.
Fig. 18 illustrates another technique for
securing tissue 99 to the bone 95, wherein two anchor
members 80 are anchored in holes 101, 103, and the
free ends of the sutures 82 are tied together over the
tissue.
It is noted that it may not be necessary to
first pierce the tissue 99 before depositing the
anchor member ~0 into the hole lOl, 103. For
instance, the anchor member 80 may be deposited within
the hole 101, 103 in the manner described above, and
the free end of the suture 82 may be threaded through
a conventional surgical needle that is used ~o pierce
the tissue. The surgical needle is then removed and
the free ends of the sutures 82 are secured as
described above.
Fig. 19 depicts an alternative embodiment of
an anchor member 110 suitable for anchoring in bone.
The anchor member 110 is substantially similar to the
anchor member 80 described earlier, except that it
includes a continuous passage 112 formed therein to
pass into one leg 114, through the base 116, and out
the other leg 115. The suture 118 is threaded through
the hole passage 112 so that t~o suture segments 120
extend from the anchor member. This confi~uration of
the anchor member ~10 allows the user to select any
type of suture for use with the anchor member 110,
depending upon the particular surgical needs.
Further, having two suture segments 120 available for
securing the tissue to the bone is often desirable.
For example, whenever an odd number of anchor members
~ ~2~1 ~
~o
llS is used, the resulting even number of available
suture segments 120 permits each segment of one anchor
member to be tied to a corresponding segment of an
adjacent anchor member, without the need for tying
more han two suture segments together.
Figs. 20 and 21 illustrate a side sectional
view and top view, respectively, of another
alternative embodiment of an anchor member 130 formed
in accordance with this invention. This embodiment is
a generally cup-shaped piece of resilient material,
such as plastic, having a base 132 with four legs 134
extending upwardly therefrom. The sharp outer edge
136 of each leg is spaced apart from an opposing edge
136 by a maximum distance D whenever the anchor member
is in the relaxed position as shown in Fig. 20. As
noted earliex, distance D is yreater than the diameter
of the hole into which the anchor member 130 is
deposited. Preferably, two holes 138 are formed in
the base 132 of the anchor member 130. A suture 140
is threaded through the holes 138.
The anchor member 130 is deposited within a
hole in a bone in a manner similar to that explained
with respect to the apparatus of Fig. 16.
Specifically, the anchor member 130 is positioned
within the tip of a hollow needle (not shown) where it
assumes a deformed position. In the deformed
position, the outer edge 136 of each leg is held near
the outer edge 136 of the opposing leg a distance d
that is less than the "relaxed~ distance D and
corresponds to the diameter of the needle bore in
which the anchor member is lodged. When the anchor
member 130 is expelled from the needle and deposited
within the hole in the bone, the intrinsic resilience
of the anchor member 130 forces the outer edges 136
against the bone, thereby anchoring the anchor member
~~2~
.
21
within the holeO The suture 140 is thereafter
available to secure tissue against the bone as
discussed above.
The anchor members 80, 110, 130 just
described may be formed of material that is absorbable
by the body. Alternatively, the anchor members may be
formed of non-absorbable material ~e.g., stainies~
steel of suitable resilience) that remains in the bone
indefinitely.
The terms and expressions that have been
employed in the foregoing specification are used
herein as terms of description and not of limitation,
and there is no intention, in the use of such terms
and expressions, of excluding equivalents of the
features shown and described or portions thereof, it
being recognized that the scope of the invention is
defined and limited only by the claims that follow.
