CA1312518C

CA1312518C - Apparatus and method for manipulating and anchoring tissue

Info

Publication number: CA1312518C
Application number: CA000564968A
Authority: CA
Inventors: John O. Hayhurst
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-04-25
Filing date: 1988-04-25
Publication date: 1993-01-12
Anticipated expiration: 2010-01-12

Abstract

Abstract APPARATUS AND METHOD FOR MANIPULATING
AND ANCHORING TISSUE

An apparatus and method for manipulating and anchoring tissue is provided. The invention is directed to solving the problem of manipulating and anchoring tissue within a joint when access to that tissue is limited, for example, during arthroscopic surgery. The apparatus includes an anchor member (10, 50) with attached suture (12, 52). The anchor member (10, 50) is lodged within the tip of a needle (14, 54), which is inserted into a joint. A tube (16, 55) fits within the needle (14, 54) and is pushed toward the needle tip to expel the anchor member (10, 50) into or behind the tissue to be manipulated or anchored. The suture (12, 52) is thereafter available for manipulating or anchoring the tissue. In one embodiment, the anchor member (80) is configured to provide anchorage of its attached suture (82) within a hole (100) drilled into a bone (96). A retainer (58, 69) slides over the suture (12, 52, 82) and secures tissue to the anchor member (12, 52) or to the bone (96) in which the anchor member (82) is anchored.

Description

:~ 3 ~

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~

~ 3 ~ 8 ,, 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 ~ ~L2~3~

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 ~ 3 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, -` 1312~8 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 ,, ~ 3 ~
. ~

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 ~3:~3~8 .

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 ~ 3:~23~

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 ~ 3 ~
.

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 ~ 3 ~

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.

~3~2~

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 ~ 3 ~ 8 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, ~ 312~

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~

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~
.

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.

Claims

1. An apparatus for insertion into a hole of predetermined diameter drilled into a bone, the apparatus providing a mechanism for anchoring tissue to the bone and characterized by:
(a) a deformable anchor member having a base and at least two legs attached to the base, each leg extending from the base to terminate in an outer end, at least a portion of the anchor member being 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 that is larger than the diameter of the hole, the anchor member being deformable into a deformed position wherein the ends of the legs are spaced apart a minimum distance that is less than the diameter of the hole thereby permitting insertion of the anchor member into the hole, while the anchor member is in the deformed position; and (b) a suture attached to the anchor member to extend from the hole in which the anchor member is inserted.

2. The apparatus of claim 1 further characterized in that the base has formed in it at least one aperture through which the suture is removably threaded to provide two suture segments extending from the anchor member and hole.

3. The apparatus of claim 1 further characterized in that the ends of the legs are formed into sharp edges that bear upon the bone when the anchor member is positioned within the hole, the edges being shaped to dig into the bone whenever tension is applied to the suture.

4. The apparatus of claim 1 further characterized in that the anchor member is sized so that when the anchor member is positioned within the hole the ends of the legs are beneath the cortical layer of the bone.

5. The apparatus of claim 1 further characterized in that the legs have outer surfaces having barbs formed therein that contact the bone to resist removal of the anchor member from the hole whenever tension is applied to the suture.

6. The apparatus of claim 1 further characterized by insertion means for inserting the anchor member into the hole, the insertion means including:
(a) a hollow needle having a tip and a butt, the needle configured for receiving the anchor member within the tip while the anchor member is in the deformed position and with the suture extending through the butt; and (b) an expulsion tube positionable within the hollow needle to be slidable therein and operatively associated with the needle for expelling the anchor member from the needle tip.

7. The apparatus of claim 6 wherein the anchor member is inserted through tissue into the hole and wherein the suture extends from the hole through the tissue, the apparatus further characterized by a retainer slidable around the suture and configured for securing the tissue against the bone near the hole.

8. An apparatus for insertion into and through tissue to provide a mechanism for manipulating and anchoring tissue within a joint of a patient, characterized by:

(a) an elongated anchor member insertable into and through the tissue and having opposing end faces, at least one end face being formed in a plane that is slanted relative to the longitudinal axis of the anchor member; and (b) a suture having one end attached to the anchor member and the other end free for manipulating and anchoring the tissue within the joint.

9. The apparatus of claim 8 further characterized by insertion means for inserting the anchor member into and through the tissue, including:
(a) a hollow needle having a tip and a butt;
(b) an expulsion member postionable within the hollow needle to be slidable therein, the anchor member being positionable within the needle tip and expellable therefrom by the expulsion member, the free end of the suture extending from the interior of the needle butt when the anchor member is positioned within the needle.

10. The apparatus of claim 9 further characterized by a retainer that is slidable with relatively little resistance along the suture toward the anchor member and slidable with relatively high resistance away from the anchor member, the retainer and suture configured for retaining tissue near the anchor member.

11. The apparatus of claim 10 further characterized in that the anchor member is formed of resilient material and is deform-able into a deformed position within the needle tip, wherein the opposing ends of the anchor member are near each other when the anchor member is in the deformed position, the ends of the anchor member moving apart when the anchor member is expelled from the needle.

12. The apparatus of claim 11 further characterized in that the anchor member is formed of resilient material that is absorbable by the tissue.

13. A device for use in anchoring and manipulating fibrous tissue such as cartilage and the like within a joint of a patient during a surgical procedure, comprising:
(a) anchoring means, including an elongate member, for attaching a suture to fibrous tissue, said anchoring means being adapted to fit within an open tip of a hollow needle;
(b) a suture attached to said elongate member; and (c) retainer means, easily slidable along said suture toward said anchoring means but thereafter resistant to movement along said suture away from said anchoring means, for retaining tension in said suture within tissue held between said anchoring means and said retainer means, said retainer being of resilient material having a pair of opposite surfaces and defining a plurality of intersecting slits extending therethrough between said opposite faces.

14. The apparatus of claim 13, said retainer being generally disc-like, having a pair of opposite faces, said slits intersecting with one another at a central location on said opposite faces, and there defining flexible pointed corner flap means for allowing said retainer to move along said suture in one direction but resisting movement in the opposite direction thereafter.

15. A device for use in anchoring and manipulating fibrous tissue such as cartilage and the like within a joint of a patient during a surgical procedure, comprising:
(a) anchoring means, including an elongate member, for attaching a suture to fibrous tissue, said anchoring means being adapted to fit within an open tip of a hollow needle;
(b) a suture, attached to said anchoring means to extend medially of said elongate member thereof; and (c) retainer means, easily slidable along said suture toward said anchoring means but thereafter resistant to movement along said suture away from said anchoring means, for retaining tension in said suture within tissue held between said anchoring means and said retaining means, said retainer means including protruding means for resisting lateral movement.

16. A device for use in anchoring and manipulating fibrous tissue such as cartilage and the like within a joint of a patient during a surgical procedure, comprising:
(a) anchoring means, including an elongate member, for attaching a suture to fibrous tissue, said anchoring means being adapted to fit within an open tip of a hollow needle and said elongate member having slanted end faces located at respective longitudinal extremities thereof, said faces lying at planes which intersect one another along a line substantially perpendicular to the length of said elongate member;
(b) a suture, attached to said anchoring means to extend medially from said elongate member thereof, said suture being attached to said elongate member at a point along the surface thereof opposite said line of intersection of said planes; and (c) retainer means easily slidable along said suture toward said anchoring means but thereafter resistant to movement along said suture away from said anchoring means, for retaining tension in said suture within tissue held between said anchoring means and said retainer means.

17. A device for use in anchoring and manipulating fibrous tissue such as cartilage and the like within a joint of a patient during a surgical procedure, comprising:
(a) anchoring means, including a resiliently deform-able member, for attaching a suture to bone tissue, said anchoring means being adapted to fit within an open tip of a hollow needle in a deformed configuration,said anchoring means having a generally cylindrical shape, a convex nose portion and a concave rear end;
(b) a suture, attached to said anchoring means, said suture extending rearwardly from said rear end; and (c) retainer means, easily slidable along said suture toward said anchoring means but thereafter resistant to movement along said suture retaining said anchoring means, for retaining tension in said suture within tissue held between said anchoring means and said retainer means.

18. A device for use in anchoring and manipulating fibrous tissue such as cartilage and the like within a joint of a patient during a surgical procedure, comprising:
(a) anchoring means including a resiliently deform-able member for attaching a suture to bone tissue, said anchoring means being adapted to fit within an open tip of a hollow needle in a deformed configuration;
(b) a suture, attached to said anchoring means; and (c) retainer means easily slidable along said suture toward said anchoring means but thereafter resistant to movement along said suture, for retaining tension in said suture within tissue held between said anchoring means and said retainer means, and anchoring means including a U-shaped portion, the legs of the U extending substantially parallel with one another in the direction toward which said suture extends and being resiliently biased to separate from one another so as to bear against the interior of a socket in bone tissue when said U-shaped portion is located therein.

19. A device for securing tissue within a joint, comprising:
(a) a hollow needle having a tip end and a butt end;
(b) an expulsion member positionable within the hollow needle to be slidable therein;
(c) an elongated anchor member positionable within the hollow needle, the anchor member having opposing end faces, at least one end face being formed in a plane that is slanted relative to the longitudinal axis of the anchor member, the anchor member being expellable from the needle by the expulsion member; and (d) an elongated suture having one end attached to the anchor member, the suture extending from the interior of the needle butt end when the anchor member is positioned within the needle and when the expulsion member is positioned within the needle, the portion of the suture near the anchor member being normally flaccid and usable for securing tissue adjacent to the expelled anchor member.

20. An apparatus for anchoring a suture within a hole in a bone, the hole having a predetermined diameter, the apparatus comprising:
a base, the base having a rounded end;
means for attaching a suture to the base; and two leg members extending from the base, the leg members being spaced apart by a distance such that upon insertion of the apparatus into the hole the apparatus fits tightly therein.

21. The apparatus of claim 20 further comprising a plurality of barb elements attached to protrude outwardly from the leg members so that upon insertion of the apparatus into the hole the barb elements bear against the portion of the bone that defines the hole.