The invention pertains to medical devices for anchoring a suture engaged with soft tissue to a bone, the devices including tissue fastening medical devices, bone anchor medical devices, bone anchor driving tools and impactor tools, and procedures for using the same.
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1. A bone anchor device comprising:
a main anchor body defining a longitudinal axis and having an external formation for engaging the main anchor body to a bone and a receiving formation; and
an eyelet pin defining a longitudinal axis and having a passage substantially transverse to the longitudinal axis through which a length of suture can be threaded;
wherein the eyelet pin is longitudinally insertable in the receiving formation from an open position, in which a suture passing through the eyelet would not be fixed in the passage and may translate within the passage, into a closed position, in which a suture passing through the passage in the eyelet pin would be fixed in the passage; a central pin disposed in the receiving formation and having a longitudinal axis parallel to the longitudinal axis of the main body, the central pin having a proximal end and a distal end; and wherein the eyelet pin has a proximal end and a distal end and includes a distal longitudinal bore running between and open to each of the transverse passage and the distal end of the eyelet pin and wherein the interaction between the distal longitudinal bore of the eyelet pin and at least a portion of the central pin form an interference fit.
2. The bone anchor device of
3. The bone anchor device of
4. The bone anchor device of
5. The bone anchor device of
6. The bone anchor device of
7. The bone anchor device of
8. The bone anchor device of
9. The bone anchor device of
a locking ring captured in the receiving formation and having an inner diameter and an outer diameter;
wherein the eyelet pin further comprises at least a first ramp formation on an outer surface thereof defining a diameter greater than the inner diameter of the locking ring when in an unbiased state, the first ramp formation adapted to cooperate with the locking ring to capture the eyelet pin in the main anchor body.
10. The bone anchor device of
11. The bone anchor device of
12. The bone anchor device of
13. The bone anchor device of
14. The bone anchor device of
15. The bone anchor device of
20. The bone anchor device of
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This application claims priority to U.S. Provisional Patent Application Nos. 60/855,831 filed Oct. 31, 2006, 60/855,828 filed Oct. 31, 2006, and 60/922,558 filed Apr. 9, 2007, all of which are incorporated herein by reference in their entireties.
The invention relates to medical devices and procedures for attaching tissue to bone.
The invention relates particularly to medical devices and to medical procedures incorporating the use of the medical devices, that can be used in the repair of tendon tears, and the like, where repair requires the reattachment of soft tissue to skeletal structures, i.e. bones.
Rotator cuff tears often require reattachment of soft tissue to skeletal structures and the explanation of the invention as hereinafter set out refers particularly to the repair of rotator cuff injuries, although it must be understood that the invention can be employed also in association with other like injuries where similar repair techniques are ordinarily employed or considered. The rotator cuff is the anatomical term given to a group of muscles and their tendons that act to move and stabilize the shoulder. These muscles extend from the scapula, i.e. the shoulder blade bone, and connect to the humerus, i.e. the upper arm, via their tendons, forming a cuff at the shoulder joint, thus serving to control different arm movements. A rotator cuff tear can result from a trauma to a shoulder or through wear and tear and be associated with one or more tendons becoming torn, leading to pain, shoulder instability and/or restricted arm movement.
Rotator cuff repair involves a surgeon reattaching each damaged tendon to the humerus. The conventional surgical process typically includes the steps of gaining access to the injured rotator cuff by making an incision in the shoulder and splitting the deltoid muscle and then removing scar tissue that has built up on each torn tendon. The surgeon then creates a trough at the top of the humerus and drills small holes through the bone, whereafter he sews the tendon to the bone with sutures passing through the holes. Other steps also may be associated with the process in order to deal with specific repair requirements. Following the process, the arm is incapacitated and healing is allowed to occur, which involves the reattachment of the tendons to the bone and which is generally a slow process.
Instead of passing sutures through holes drilled in the humerus for securing the tendon to the humerus, it is also known to use permanent anchors with sutures attached, inserted in the humerus, for this purpose.
More recently, arthroscopic surgery is being employed for rotator cuff repair. The surgery is performed through one or more small incisions. The surgeon observes the area of interest via a display screen which displays live images from a camera that is placed in a tube (cannula) passing through a small incision into the joint space. The instruments used are thin and are contained in separate cannulas that are inserted into the shoulder via separate small incisions. This arthroscopic surgery process includes placing anchor devices to which sutures are engaged for securing tendons to the humerus. In some techniques a pilot hole is required prior to placement of an anchor device. Each suture is passed through the tendon with a suture passing instrument. In most cases, all of the sutures are passed before tying. The sutures are then tied to anchor devices by the technique of arthroscopic knot tying. Various difficulties are associated with arthroscopic surgery as above envisaged.
The location of and the angle of a pilot hole for an anchor device is difficult to appreciate arthroscopically, rendering the location of anchor devices in their holes difficult.
The tying of sutures arthroscopically is very challenging.
Insofar as suture management is concerned, present techniques often require multiple sutures to be placed in position first and then to be tied to their anchor devices, often creating a “spider web” with entanglement of sutures and resulting in accidental pull-out of sutures and failure to recognize appropriate suture strands to be tied. Placing of sutures also presents difficulties insofar as multiple passes through the tendon are often required and snaring of suture portions by the soft tissue forming a tendon also can occur, resulting in difficulty in retrieving sutures into the portal of the equipment used.
In accordance with a first aspect of the invention, a tissue fastener device is provided for attachment of the soft tissue to bone, the tissue fastener device comprising a body that defines a shank portion and a hook formation extending from the shank portion, the shank portion defining a formation that permits fastening to bone with a fixation device such as a suture, pin, peg or a screw and the hook formation being configured to be engaged within soft tissue through manipulation of the body of the tissue fastener device.
In accordance with a second aspect of the invention, a procedure is provided for attaching soft tissue to bone with the aid of sutures including providing, through incision into the body, access to the soft tissue and to the bone to which it must be attached, providing a tissue fastener device comprising a body that defines a shank portion and a hook formation extending from the shank portion, the shank portion defining a formation that permits fastening to bone with a fixation device such as a suture, pin, peg or a screw and the hook formation being configured to be engaged within soft tissue through manipulation of the body, and, in the example of the fastener being a suture, tying the suture to the body of the tissue fastener device via the formation defined therefore by the shank portion, engaging each suture tied to a tissue fastener device with the soft tissue to be attached to a bone by engaging the hook formation of the tissue fastener device with the soft tissue, and anchoring each suture engaged with the soft tissue under tension to the bone.
In accordance with a third aspect of the invention, a bone anchor device is provided for anchoring at least one suture engaged with soft tissue to a bone comprising an anchor main body for insertion into a bone and a pin having a longitudinal axis and a passage transverse to the axis through which at least one suture can be passed, the anchor main body defining a receiving formation therein for receiving the pin, the pin being movable in the body between a first position that permits at least one suture to be relatively freely slid through the passage, tensioning the sutures attached to the soft tissue, and then moving the pin to a second position in which the at least one suture is relatively securely held. In accordance with fourth aspect of the invention, a procedure is provided for anchoring sutures engaged with soft tissue to a bone including providing, through incision into the body, access to the bone, providing for a suture engaged with the soft tissue, providing a bone anchor device comprising a substantially cylindrical body for insertion into a bone and a pin having a longitudinal axis and a passage transverse to the axis through which a suture can be threaded, the cylindrical body defining a receiving formation therein for receiving the pin with a suture threaded through the passage of the pin, the pin being deployable into a locking position in which a suture passing through the formation is securely held between the cylindrical body and the pin, affixing the body of each bone anchor device into the bone, and passing each suture engaged with the soft tissue through the passage defined in the pin of the bone anchor device, and, while holding the suture under tension, deploying the pin into its locking position in the receiving formation of the cylindrical body, for anchoring the suture and thereby the soft tissue engaged by the suture to the bone.
Further features of the various aspects of the invention are described hereinafter with reference to the accompanying diagrammatic drawings. In the drawings:
A medical system in accordance with a first embodiment of the present invention comprises two primary components, namely, a bone anchor device 1 as shown in
Referring initially to
The anchor main body 10 defines a leading end 14 and a trailing end 16 and an external formation such as a thread 18 extending externally along the length thereof from its leading end towards its trailing end to help secure the body 10 to bone. At its trailing end 16, the body 10 defines a head formation 20, the head formation 20 being geometrically profiled to permit engagement with a screw driver-type tool, for screwing the body into a bone. The body 10 also defines a receiving formation therein that is in the form of a cylindrical blind bore 22, the receiving formation 22 being particularly configured to frictionally receive the eyelet pin 12 therein.
The eyelet pin 12 could be formed of the same material as the anchor main body 10, the pin comprising a substantially cylindrical pin that defines a passage 24 therethrough near a proximal end thereof and a longitudinal slot 26 that extends therein from the distal end toward the proximal end near which the passage 24 is defined. The pin thus defines two legs 28 on opposite sides of the slot 26. The pin 12 is particularly configured to be securely locatable within the receiving formation 22 defined by the anchor main body 10 by a friction fit, inherent resilient deformability of the material forming the pin and the configuration of the slot serving to enhance required location of the pin within the receiving formation 22 defined by the body 10. The exact configurations of the anchor main body and of the pin are greatly variable.
Insofar as the tissue fastener 2 is configured for use in an arthroscopic procedure, the end region of the shank portion 32 of the body 30 where the hole 36 is defined is configured to engage an engagement formation of an applicator tool, the applicator tool providing for manipulation of the tissue fastener device 2 for engaging soft tissue, particularly via a cannula located in an incision in a body of a person in a location where it provides access to the location where the tissue fastener device 2 must be engaged with soft tissue. Although not essential, it is envisaged that such an applicator tool can be cannulated to provide for a suture to pass through the cannula, thus to provide for the free end of a suture tied to the tissue fastener device 2 to remain conveniently accessible externally of the body of a person following engagement of the device with soft tissue, as is described in more detail hereafter.
It must be understood that a specific arthroscopic applicator tool will be provided for use with the tissue fastener device 2 and/or that the tissue fastener device 2, as described, may require modification for cooperating with a particular tool, in order to facilitate its use as hereafter described.
The tissue fastener device 2 may be formed of a metal material of a type already used for medical devices used within the body of a person, e.g., a metal or metal alloy such as titanium, stainless steel and cobalt-chrome alloys; a suitable polymeric material that is nonabsorbable, such as polyethylene, poly-ether-ether-ketone (PEEK), poly-ether-aryl-ketone (PEAK); a resorbable polymer selected from homopolymers, copolymers and blends of polylactide, polyglycolide, polyparadioxanone, polytrimethylene carbonate or polycaprolactone; or composites of the aforementioned with biocompatible inorganic substances such as carbon, hydroxyapatite, beta tricalcium phosphate, other calcium phosphate ceramics or calcium sulfate.
The bone anchor device 1 and the tissue fastener device 2 are configured particularly for use in a medical procedure for anchoring sutures engaged with soft tissue to a bone, thereby attaching the soft tissue to the bone. Sutures engaged with soft tissue to be anchored to a bone within the procedure may be engaged with the soft tissue by any known method, although for the first procedure described hereafter with reference to
The procedure as above envisaged is typically applied in association with rotator cuff repair and is hereinafter described in association with such a repair procedure, although it must be appreciated that the medical devices 1 and 2 as above described also can be used in association with other procedures that require soft tissue to be attached to or re-attached to skeletal structures, i.e., to bone.
Rotator cuff repair is required where a tendon that acts to stabilize the shoulder has torn and thus is to be reattached to the humerus, i.e. the upper arm bone, thereby to re-establish normal arm movement. As envisaged above, such repair ordinarily involves a surgeon gaining access to the tendon and the humerus through incision, engaging sutures to the tendon in a conventional manner, and then sewing the sutures to the humerus via holes formed therein for anchoring to the humerus. Anchoring to the humerus by tying the sutures to anchor devices located in the humerus also is known. The same principles apply also to the procedure that is explained hereafter with particular reference to
Referring now to
The general procedure in association with the location of cannulas 44, which can provide access to required locations to permit the repair procedure to be carried out, is already well known and is thus not described further herein. Each cannula located in an incision provides access to locations where the procedure must be performed, particularly also for arthroscopic tools or instruments that can serve to suitably manipulate the medical devices above described, within the procedure. The configuration of such arthroscopic tools or instruments are generally well known, but insofar as existing tools or instruments may not be specifically configured to accommodate manipulation of the medical devices described, existing tools or implements may be suitably adapted or new tools or instruments may be designed, using known principles, in order to facilitate the procedure.
With reference to
With reference to
The procedure thus requires anchoring of the sutures 46 to anchor main bodies 10 via eyelet pins 12, and in this regard it must be understood that each anchor main body and its associated eyelet pin may serve to anchor either a single suture or two or more sutures with respect thereto. With reference to
Referring now to
In this case, a bone anchor device 1 (including an anchor main body 10 and an eyelet pin 12) is provided in combination with at least one suture 46, threaded through the passage defined at one end of the eyelet pin 12, and a tissue fastener device 2, tied to the suture. The eyelet pin 12 is partially inserted in the receiving formation defined therefore in the anchor main body 10, free displacement of the suture 46 still being permitted.
With a cannula 44 being located that provides access to the humerus 42, the anchor main body 10 of the medical device is again screwed into the humerus in a desired anchoring location. This is achieved in the same way as before and provides the configuration shown in
With reference to
With reference to
It will be understood that both the above described procedures can be altered in various different respects. For example, for the procedure described with reference to
Some of the benefits associated with the use of a tissue fastener device in accordance with the invention within a medical procedure are explained hereafter particularly in relation to a rotator cuff procedure as above described, although it must be understood that some or all of these benefits may be associated also with other procedures as will be clearly apparent.
The known state-of-the-art procedures usually require placement of all sutures through the rotator cuff prior to securing of the sutures to the bone. This is necessary because the sutures are deployed into the rotator cuff tissue by a device that penetrates the full thickness of the cuff tissue; however, placement of a suture through the full thickness of the cuff tissue after a previous suture has already been secured to the bone, will potentially weaken or even disrupt the previous suture fixation. This problem cannot be resolved by moving the point of suture penetration further away from the preceding suture penetration point, as this will result in less secure fixation. One of the principle goals of rotator cuff repair is to recreate the anatomical footprint of the tendon's attachment via secure fixation and, for the reasons explained, this goal will be compromised by a “tie-as-you-go” method. It will be understood by those skilled in the art that the smaller the tear within the tendon, the less room there will be for safely placing a following suture through the torn tissue of the tendon without disrupting or weakening the prior-located suture(s).
As such, by facilitating a “tie/secure-as-you-go” procedure, the above problem of suture management is largely resolved and this is in fact achieved with the use of the tissue fastener devices of the invention, which permit “tie/secure-as-you-go” procedures. Also because the state-of-the-art procedures for the reasons explained, require multiple sutures to be engaged with rotator cuff tissue before anchoring thereof to bone, suture management of untied multiple suture strands is a major technical challenge in state-of-the-art arthroscopic rotator cuff repair. The problems intensify as the number of sutures are placed in position, a maze of sutures often leading to inadvertent tying of incorrect suture pairs, failure to find sutures in the procedure field, inadvertent release of sutures from their anchors and tangling of sutures around instruments and among other sutures and soft tissues. This suture management within the rotator cuff procedure above described and with the aid of the medical devices of the invention is greatly facilitated.
Still further, upon completion of a rotator cuff repair as envisaged, there are occasionally areas where the tendon is not adequately tensioned and not adequately laying on bone. For the reasons mentioned above, a surgeon cannot use a state-of-the-art suture passing instrument to augment the repair. However, with the use of the tissue fastener device 2 of the invention, a surgeon will have a simple option of augmenting and thereby to fine tune a repair without risking the existing repair sutures.
It is also known for suture passing devices to be used for deploying sutures into the rotator cuff. With the use of these devices there are several steps involved in the process, with each step being exposed to technical difficulties. These steps particularly involve the loading of sutures outside the portal defined by a cannula, grabbing the tendon in the jaws of the suture passing device arthroscopically, deploying the sutures arthroscopically, withdrawing the suture-passing device, and then retrieving the sutures into a portal. Alternately, cannulated suture shuttling and penetrating devices also are commonly used that involve several complex steps. Specifically, first the rotator cuff is pierced with the device. This is technically difficult, and to facilitate the procedure, devices that have various curves and or twists have been designed. Then, typically, a suture or wire (pullthrough stitch) is advanced through the cannulated shuttling device. This wire or suture is then retrieved into a separate cannula. Then, the suture to be used in the rotator cuff repair is placed through a loop or penetrating device in the pull-through stitch and pulled (shuttled) through the tendon. These complex processes are eliminated with the use of the tissue fastener device 2 of the invention, which affords a surgeon a simple method of attachment of suture to the tendon.
The hole 36′ may be counterbored (not shown) so that the head 102 of the screw 100 will be substantially flush with the surface of the shank portion 34 of the tissue fastener device 2. The screw may be polyaxial. For instance, the hole in the tissue fastener device may be spherical and the screw may have a mating spherical head so that the screw can pivot about the interface between the spherical head and the spherical seat in the hole through a defined cone of freedom. In one embodiment, the spherical head and/or the spherical seat in the hole may have ridges or other formations for interlocking with each other to generate a stronger grip between the screw head and the hole. The ridges may be plastically deformable when the screw is forced down into the seat to provide even stronger gripping there between.
In order to even further increase rigidity and help prevent backout of the bone screw 100, a mechanism to directly fixedly attach the screw 100 to the hole 36 in the tissue fastener device 2 (rather than just trapping the shank 32 of the tissue fastener device 2 between the head 102 of the screw 100 and the bone surface) may be additionally provided. For instance, hole 36′ may be internally threaded so that, when screw 100 is screwed into the bone, it also threadedly engages and becomes directly fixed to the tissue fastener device 2, not only the bone 42. In a preferred embodiment of this feature, the threads 104 on the screw 100 for engaging the hole 36′ are different than the threads 103 on the screw 100 for engaging the bone (since thread formations most suitable for threading into bone are different than thread formations most suitable for mating contact in a pre-threaded hole). In such an embodiment, the proximal portion of the shank of the screw 100 would bear threads 104 adapted for engaging the threads in the hole 36′ and the distal portion of the shank of the bone screw 100 would bear threads adapted for engaging bone.
The tissue fastener device 2 may be engaged with the soft tissue 40 in the usual fashion as discussed above in connection with
Thereafter, a suitable surgical tool can be inserted through a cannula that can guide the tissue fastener to a position such that the hole 36 is positioned above the desired location on the bone for the screw 100 to be inserted. The bone screw 100 is then inserted through a cannula (not shown) into the hole 36 and screwed into the bone using a suitable driver (not shown) in order to attached the tissue fastener 2 directly to the bone without the use of sutures.
In an alternate embodiment of the tissue fastener device, the shank may include more than one hole so that the tissue fastener device can attached to the bone using multiple screws, pegs, tacks, or other bone fastening devices.
Insofar as the procedure hereafter described is an arthroscopic procedure, the repair procedure is initiated by locating cannulas 44 (only one shown) in incisions that are positioned so that access is provided to the tendon 40 and the humerus 42 to which the tendon is to be attached, this access particularly accommodating the use of arthroscopic tools. The location of cannulas 44 and normal preparation in relation to a repair is conventional and, as such, is not described further herein.
Particularly, within an arthroscopic procedure as envisaged, the first step in the procedure typically involves the formation of a pilot hole 37 in the humerus 42 in a location where sutures must be anchored to the humerus. The pilot hole 37 is formed arthroscopically with the aid of a suitable tool that facilitates this. The pilot hole 37 particularly is formed to receive an anchoring device 39 therein, particularly a device to which sutures can be tied or otherwise secured for effective anchoring of the sutures to the humerus. The mode of location of an anchoring device is variable and is determined by the type of anchoring device involved, it being possible, for example, to locate an anchoring device without the requirement of first forming a drill hole.
Each suture 46 (there may be one or more) to be engaged with the tendon 40 and anchored to the anchoring device 39 to be located in the pilot hole 37 is then tied to a separate tissue fastener device 2, particularly via the hole 36 defined in the body 30 thereof. Thereafter, each body 2 is operatively engaged with an applicator tool that is configured to permit engagement of the tendon 40 by the tissue fastener device 2 via its hook formation 34, in the configuration as shown in
With each suture 46 (only one shown) engaged with the tendon 40, each suture is tied under tension to an anchoring device 39 that is then located in the pilot hole 37 provided therefore. Insofar as this anchoring procedure is already known and insofar as it does not form a part of the present invention, this is not described further herein. The above procedure is performed for each further anchoring device to be used and the sutures to be anchored thereto.
A second embodiment of the bone anchor device is shown in
The anchor main body 210 defines an operative leading end 214 and an operative trailing end 216 and a self-tapping thread 218 extending externally along the length thereof from its operative leading end towards its operative trailing end. At its trailing end 216 the body defines a head formation 220, the head formation being geometrically profiled to permit engagement with a screwdriver-type tool for screwing the body into a bone. The body 210 also defines a receiving formation 222 therein that is in the form of a cylindrical blind bore, the receiving formation 222 being particularly configured to securely receive an eyelet pin 212 therein.
The eyelet pin 212 defines a passage 224 therethrough near its proximal end and a longitudinal slot 226 that extends therein from the distal end. The pin thus defines two legs 228 on opposite sides of the slot 226. The pin 212 is configured to be securely locatable within the receiving formation 222 defined by the anchor main body 210, at least partially due to an effective friction fit, as in the first embodiment described above in connection with
As in the first embodiment of
Referring now to
The eyelet pin 342 again defines a passage 356 therethrough near the proximal end thereof and a longitudinal slot 358 that extends therein from the distal end. The pin thus again defines two legs 360. The two legs, in this case, have bands 362 of a resiliently deformable material located thereon which, upon the location of the pin 342 in the receiving formation 352, enhance the secure location of the pin within the receiving formation.
With a suture 46 passing through the passage 356 defined by the eyelet pin 342 and with the pin 342 fully inserted in the receiving formation 352 of the anchor main body 340, it will be appreciated that the suture 46 will take a tortuous path in the bone anchor device, as shown at 335 in
In relation to the bone anchor devices described above, it must be appreciated that their design may vary in different respects. By way of example and with reference to
The bone anchor devices 1, 200, 300, 300′, described hereinabove may be used in connection with various different procedures that involve the anchoring of soft tissue to bone, which is required in relation to the repair of various different injuries, as described hereafter. This includes any of the surgical procedures described hereinabove such as those described in connection with
It will be understood that, in relation to the anchor main body 210, the head formation 220 in the second embodiment of
Following the location of the anchor main body 210 as shown and in order to provide for the required location of a damaged tendon 74 with respect to the humerus 70 with the aid of a suitable arthroscopic passing instrument, one end of the suture is passed through the tendon 74 and then again passed through the passage in the eyelet pin 212, thus in effect forming a closed loop 76, whereby the tendon is engaged. By thereafter applying tension to the two end segments of the suture 72, the tendon 74 is pulled towards the bone anchor device 200 into a required location with respect to the humerus 70 where re-attachment with the humerus is desired, following which the eyelet pin 212 is displaced into its closed configuration in which it is fully inserted into its receiving formation 222 defined by the anchor main body 210 to thereby effectively anchor the suture with respect to the bone anchor device 200. This position of the tendon 74 with respect to the humerus 70 is illustrated in
It will be understood that essentially similar procedures can be performed except using the tissue fastener illustrated in
With reference to
The other anchor main body 340 has an eyelet pin 342 fully inserted therein, the eyelet pin 342 having a suture 86 passing through its passage. The suture 86 thus defines suture segments, 86.1 and 86.2 respectively that extend from the eyelet pin 342.
With the anchor main bodies 210 and 340 being located as shown, with the aid of a suitable passing instrument, each suture segment 86.1 and 86.2 is passed through the tendon 88 and then through a loop formation 84 in one of the shuttling sutures 82. Thereafter, by pulling on the ends of the shuttling sutures 82 remote from the loop formations 84, the shuttling sutures together with the suture segments 86.1 and 86.2, are pulled through the passage in the eyelet pin 212 of bone anchor 200, thus providing for each suture segment to form a loop that extends from the eyelet pin 342 of bone anchor 300 through the tendon 88 and back to the eyelet pin 212 of the bone anchor 200. Thereafter, by pulling on the suture segments 86.1 and 86.2, the tendon 88 is pulled towards its desired location with respect to the humerus 80 in which it should attach itself to the humerus 80, following which the eyelet pin 212 is displaced into its closed position, fully inserted in the receiving formation of the anchor main body 210. Thereby, the suture segments 86.1 and 86.2 are effectively anchored with respect to the bone anchor device 200.
In alternate embodiments, this surgical technique can be practiced with medial bone anchors of other designs, including conventional designs, than the bone anchor 300 of the present invention.
As a variation of the above sixth procedure, and as illustrated in
Bone anchor device 400 in accordance with the fourth embodiment comprises a threaded anchor main body 401 (shown disembodied from the device in
In other embodiments of this (or any of the other anchor main bodies described herein), the threads 425 on the anchor main body may be eliminated or reduced in size or replaced with ridges, striations, or other external formations and the bone anchor can be inserted into the bone by pounding (as in the nature of nail), instead of screwing. In such embodiments, a hole may be pre-drilled into which the anchor main body 401 is inserted.
A central pin 402 extends longitudinally in bore 418. The central pin 402 has a diameter slightly smaller than the diameter of distal bore segment 418c of anchor main body 401 such that it fits within segment 418c snugly but freely slidably therein in the longitudinal direction and freely rotatable about its longitudinal axis. In a preferred embodiment of the invention, the bore 418 and the pin 402 are cylindrical so that the pin 402 can rotate about its longitudinal axis relative to the anchor main body, which is a useful feature in many applications, as will be discussed in more detail below. However, in other embodiments, they may have non-cylindrical profiles since it is not required that the elements be rotatable relative to each other.
The proximal end 408 of the central pin 402 may be textured as shown to help grip sutures as will be discussed in more detail herein below. The texturing may take any number of forms. In one embodiment as illustrated, it comprises a series of peaks and valleys in the nature of an egg carton type shape. However, in other embodiments, the texturing may comprise parallel ridges, corrugations, serrations, divots, or general roughening of the surface. In yet another embodiment, a bore as shown in phantom at 408a in
Next, an eyelet pin 403 (shown separately in
Distal bore 417 is open to and in communication with the eyelet 409. The diameter of distal bore 417 is equal to or slightly smaller than the diameter of central pin 402 so as to form an interference fit with the central pin, as will be described in more detail herein below. Thus, when assembled (in either the open position shown in
The distal portion of eyelet pin 403 includes two ramp formations 406 (near the distal end) and 407 (intermediate the distal end and the eyelet 409).
The proximal portion of the eyelet pin is a breakaway portion that will be removed from the body prior to the end of the surgery. The breakaway portion 410 is defined by a weakened section that can be broken relatively easily. This may be provided by a thinning of the material of the eyelet pin, such as by fabricating a radial notch or V-groove in the material, as illustrated at 413 in
The eyelet extension portion 410 serves several important functions. For instance, essentially the rest of the bone anchor device 400 other than extension 410 is embedded in and below the bone surface after installation of the bone anchor device in bone and, thus, is extremely difficult for the surgeon to see once installed, particularly in an arthroscopic procedure. However, the breakaway portion 410 of eyelet pin 403 protrudes substantially from the bone and is, therefore, easy to visualize. In one embodiment, at least the extension portion 410 of the eyelet pin 403 is brightly colored to even further enhance its visibility.
A locking ring helps retain the eyelet pin 403 in the anchor main body. In the embodiment shown in
Locking ring 404 is made of a strong resilient material such as a metal or polymer so that, upon application of sufficient force in the radial direction, it can be spread radially outwardly, or squeezed radially inwardly, to change its diameter and return elastically when the force in the radial direction is removed. The inner and outer surfaces 404c, 404d of locking ring 404 are conical rather than cylindrical is shape. That is, inner and outer surfaces 404c, 404d are not parallel to the longitudinal axis 405 of locking ring 404 (i.e., up-down in
Locking ring 404 is designed such that the required amount of force to make that happen is greater than could normally be applied accidentally, but that will permit ramp formations 406 and 407 to pass through locking ring by a moderate strike with a mallet on the proximal end of eyelet pin 404 during assembly or during surgery such, as will be described in further detail herein below.
An insert 405 is disposed in the proximal segment 418a of axial bore 418 in the anchor main body 401, as seen in
The inner diameter of the distal segment 431 of insert 405 is smaller than the largest external diameter of locking ring 404. The inner diameter of intermediate segment 418b of bore 418 in anchor main body 401 is smaller than the smallest outer diameter of locking ring 404. Accordingly, locking ring 404 is captured in segment 418a of bore 418 of anchor main body 401 between shoulder 421 between bore segments 418a and 418b and the distal end 405b of insert 405. The longitudinal length of insert 405 is selected so that, when insert 405 is fully inserted in bore 418 with its proximal end 405a essentially flush with the proximal end of anchor main body 401, the distance between the distal end 405b of insert 405 and shoulder 421 in axial bore 418 is slightly greater than the height of locking ring 404, thus essentially capturing locking ring 404 in the position as shown in
The bone anchor device 400 is assembled by first inserting the central pin 402 into bore 418 in the anchor main body 401. Particularly, it is inserted into the distal bore segment 418c of the anchor main body 401, as previously mentioned. Next, locking ring 404 is inserted into bore 418 where it will sit on shoulder 421. Next, insert 405 is press fit into proximal section 418a of bore 418, as previously described to capture locking ring 404 between insert 405 and shoulder 421.
Then, eyelet pin 403 is inserted into bore 418. Specifically, eyelet pin 403 falls readily through proximal bore segment 418a until it reaches central pin 402. whereupon it must be forced further downward over central pin 402 into an interference fit between the central pin 402 and the distal bore 415 of the eyelet pin 403, In addition, sometime after central pin 402 is in distal bore 415, ramp formation 406 comes into contact with the inner surface 404c of locking ring 404. Particularly, the largest diameter of ramp formation 406 is larger than the smallest diameter of the inner surface 404c of locking ring 404 when locking ring 404 is in its unbiased condition. Only upon application of significant downward force applied to ramp 406 on locking ring 404 will locking ring 403 be forced to expand radially sufficiently to permit ramp 406 to pass through.
Accordingly, sufficient force is applied downwardly on eyelet pin 403 to permit ramp formation 406 to pass through locking ring 404 (while simultaneously overcoming the continuing resistance to longitudinal movement of the eyelet pin 403 relative to the central pin 402 due to the aforementioned interference fit between the central pin 402 and the distal bore 415 of the eyelet pin 403. Once ramp 406 is through, the force is relieved and locking ring 404 returns to its stress-free state. At this point, the eyelet pin is now constrained in anchor main body 401 in the open position by virtue of first ramp formation 406 preventing the, now joined, eyelet pin 403 and central pin 402 from being pulled out proximally and the interference fit between central pin 402 and eyelet pin 403 preventing the joined eyelet pin 403 and central pin 402 from being pushed further into the bore 418 than the point at which the distal end of center pin 402 bottoms out in bore portion 418c. Accordingly, eyelet pin is axially trapped in anchor main body 401 with no or a very limited range of axial movement.
Only when sufficient downward force is again applied to eyelet pin 403 to (1) overcome the resistance to relative axial movement between the center pin 402 and the eyelet pin 403 resulting from the interference fit and (2) cause ramp formation 407 to expand locking ring sufficiently for ramp 407 to pass through locking ring 404 can eyelet pin 403 be disposed into the closed position as shown in
The locking ring 404 illustrated in the Figures is exemplary. Other devices, particularly, other elastically deformable rings, can be substituted for the locking ring, such as an elastically deformable closed ring or a split ring (neither shown in the Figures).
As will be described in further detail immediately below, the ends of a suture shuttling mechanism, such as a wire or suture loop 411 or a long suture with a loop at each end threaded through the eyelet pf the eyelet pin of a bone anchor device of the present invention, may run up the cannula 503 of the driver tool and extend into the hollow handle. The ends of the suture shuttling wire (or suture) may be wrapped around two pins 506 inside of the handle 503 for stowage and safe keeping prior to and during surgery. The handle can include a cap 509 to close off the handle if desired for better containment of sutures or suture shuttling mechanism 411, as will be described in detail further below. The bore is also open at recess 507b to the distal end of the cannula 507. The recess 507b at the distal end of the cannula is matingly shaped to engage the shaped head 423 of the anchor main body 401 of the bone anchor device so as to impart rotation to the anchor main body 401. As shown, when the driver 500 is engaged with the head of the anchor main body 401 of the assembled bone anchor device 400, the proximal end of the eyelet pin 403 extends within the cannula 507 of the driver 500. Preferably, the recess 507b is fashioned with gripping means, such as a slight interference fit over part of the mating surfaces of head 423 and recess 507b, so as to temporarily grip the head 423 of the anchor main body and hold it firmly so that the bone anchor device will not fall out of the driver unintentionally, but which can be released with moderate force once bone anchor 400 has been surgically located.
The bone anchor device of
In fact, the various bone anchor and tissue fastener devices disclosed herein may be used in any number of surgical procedures, including those specifically described herein. In some such procedures, it may be desirable to provide a suture shuttle mechanism directly associated with the bone anchor device for shuttling sutures from the tissue fastener device or tissue (if no tissue fastener device is used) to the bone anchor device and, particularly, through the eyelet 409. In accordance with such embodiments, a shuttling mechanism comprising a flexible elongated member such as aforementioned wire loop 411 may be provided as shown in
In any event, in an exemplary procedure, the surgeon would pull on one end of the loop, e.g., end 411a, until the other end 411b is released from the distal recess 507b of the cannula 507 of the tool 500 and into the deployed state. Then, the surgeon would thread the suture(s) to be shuttled through the eyelet 409 of the bone anchor device through the deployed end 411b. After the sutures have been threaded through end 411b, the surgeon would merely need to grasp end 411a with his hand and pull so as to pull end 411b through the eyelet 409 and up through the cannula 507 until the end 411b of the loop 411 comes completely through the cannula 507, carrying the suture(s) with it. The surgeon can then disengage the suture(s) from the loop and manipulate the suture(s) directly, e.g., so as to pull the required tension on them before locking the eyelet in the closed position and cutting the free ends of the sutures.
The shuttling mechanism 411 may be made of thin, flexible wire. However, in alternate embodiments, it may be fabricated of any string or filament and, in fact, may be formed of suture itself. In an even further embodiment of the invention, the suture shuttle 411 need not be a closed loop. For example, the shuttling mechanism might be comprised of a length of suture folded in half, wherein the fold at the midpoint of the suture comprises the distal end 411b of the shuttling mechanism 411 and the two ends of the suture comprise the proximal end of the suture shuttle. To assist with shuttling, small loops may be formed in the ends of the suture (or other filament), such as illustrated by the suture shuttle shown in
The bone anchor device 400, including the anchor main body 401, the central pin 402, the eyelet pin 403, the locking ring 404, and the insert 405, is delivered to the surgeon in the assembled, open state as shown in
Once installed, the surgeon will shuttle sutures through the eyelet of 409 in the eyelet pin 403 either using a shuttling mechanism such as the wire shuttling device 411 or another device so that one or more sutures pass through eyelet 409. Then, the surgeon will place an impactor tool into the proximal bore 415 in the extension portion 410 of eyelet pin 403. In an arthroscopic procedure, this would be done through a cannula. Then, while the surgeon is tensioning sutures acting on the tissue to locate the tissue in an appropriate anatomical position, sufficient force would be applied to the proximal end of the impactor tool, such as by hitting it with a mallet or using it in conjunction with a spring-loaded or pneumatic impacting device to pound the eyelet pin 403 with sufficient force to cause the second ramp formation 407 to spread apart locking ring 404 allowing it to pass through so that the eyelet pin 403 slides down over the central pin 402 into the closed position as shown in
As the eyelet pin 403 is driven down into the closed position, the suture(s) 46 passing through the eyelet at 409 gets trapped in at least one of three locations. First, as seen in
In addition, depending on the diameter of the central pin 402 relative to the cross section of the eyelet pin (i.e., the area in the direction transverse to the direction of the passage through the eyelet between its ends 409a and 409b), it is possible for sutures to become trapped between the radial circumferential surface of the central pin 402 and the side walls of the eyelet. These locations for trapping sutures 46 can be seen, for instance, in
In addition, the suture(s) take on a tortuous shape, such as the W shaped illustrated in
In one embodiment of the invention, the features are small enough and deep enough so that they individually bore into the suture and split the fibers of the suture to provide an even stronger grip.
In addition, the suture is crushed between the surface 416 of eyelet pin 403 and the surface of the inner surface of the distal segment 433 of insert 405 at the transverse ends 409a, 409b of the eyelet 409. Specifically, the outer surface 416 of the eyelet pin 403 just above the eyelet 409 has a diameter relative to the inner diameter of the proximal segment 433 of insert 405 such that the clearance between the two surfaces is less than the width of the suture. The clearance preferably also may be somewhere between zero and ½ of the diameter of the suture, and more preferably somewhere between ⅛ and ¼ the diameter of the suture.
Note that the eyelet 409 need not even be completely within the receiving formation for there to be significant capturing of the suture. Specifically, even if the eyelet is only partially within the receiving formation in the longitudinal direction when in the closed position, the suture will be compressed between the roof 414 of the eyelet pin and the proximal end of the main anchor body as long as the distance (or clearance) between the roof 414 of the eyelet pin and the proximal end of the main anchor body in the longitudinal direction is less than a width of a suture (and those two surfaces are not too far from each other in the radial (or transverse) direction.
In alternate embodiments, the central pin 402 need not compress the suture against the roof of the eyelet at all, there being sufficient crushing and fixing of the suture in the other two locations in the lateral space between the inner diameter of the proximal portion 433 of the insert 405 and the surface 416 of eyelet pin 403.
In yet other embodiments, the roof 414 of the eyelet pin 403 may also be configured to help grip the suture. For instance, it may be provided with mating features to the features on the proximal end 408 of the central pin 402. Alternately, the roof 414 may have different features, such as roughening, serrations, corrugations, ridges, etc. In even further embodiments, the proximal end 408 of the central pin 402 and the roof 414 of the eyelet pin 402 may simply have mating shapes such as a V-shaped groove and a V-shaped protrusion or a ball and socket.
In yet other embodiments, a plug or insert may be affixed to the roof of the eyelet 409 to provide better gripping. Such a plug or insert may have some of the aforementioned features. In other embodiments, the insert may comprise a high friction material, such as silicone having a high frictional coefficient or any combinations of any of the above-noted features. It may also be fabricated from a dissimilar metal from the remainder of the eyelet pin 403. In yet other embodiments, it may comprise a rubber bumper or a leaf spring.
In a preferred embodiment of the invention, the proximal end of insert 405 is rounded over or flared, as shown by reference 428 so as to eliminate any sharp edges from contacting the suture and possibly causing it to tear or break.
The distal end of the rod 619, as best seen in
In operation, when it is time to drive the eyelet pin 403 from the open position illustrated in
In use, after positioning the impactor tool over the eyelet pin extension portion 410 as shown in
Specifically, when the surgeon strikes the proximal end 607 of the impactor tool 600, pin 623 descends into bore 415 and drives eyelet pin 403 down into anchor main body 401 to the closed position shown in
Preferably, the diameter of the pin 623 is slightly larger than the diameter of the proximal bore 415 of the eyelet pin such that the pin 623 forms an interference fit inside the bore 415 at this time. Preferably, the interference fit is relatively weak so that the eyelet pin 403 can be removed from the impactor tool 600 at a later time.
When the eyelet pin 403 is in the open position, the V-groove 413 defining the breakaway portion 410 of the eyelet pin is preferably proximal to the bumper 631, as shown in
After the eyelet pin 403 is driven down into the closed position, the impactor tool 600 is then used to break off the breakaway portion 410 of the eyelet pin 403. This is achieved by rocking the impactor tool (and the cannula within which it is inserted in an arthroscopic procedure) back and forth so that it pivots about the bumper 631 engaged with the top of the anchor main body 401. Particularly, when eyelet pin 403 is in the closed position, the V-groove 413 in the eyelet pin 403 is essentially even with the top of the anchor main body 401, and thus with the bottom of the bumper 631. The bumper permits the impactor tool 600 to be rocked back and forth so that the V-groove can be broken without metal to metal contact between the impactor tool 600 and the anchor main body 400. Once broken, the breakaway portion of the eyelet pin will stay inside the impactor tool because of the weak interference fit between the pin 523 at the end of the rod 619 pf the impactor tool 600 and the proximal bore 415 of the eyelet pin. Alternately or additionally, the hole 632 defined by the ring-shaped bumper may be designed to be slightly smaller than the diameter of the extension portion 410 of the eyelet pin so that the bumper must slightly deform radially outwardly when it is slipped over the extension 410 providing a tight, but still slidable fit with the extension 410. This would provide an alternative or additional means of retaining the breakaway portion 410 of eyelet pin 403 inside the impactor tool 600. The impactor tool 600 can then be removed with the breakaway portion 410 contained therein.
In other envisioned embodiments of the invention, a tool that is capable of delivering a precisely controlled striking force may be used instead of a simple mallet. The tool would be adapted to fit over the proximal end 607 of the rod 619 and to deliver a blow along the longitudinal axis of the rod 619. For instance, Applicants envision a spring-loaded tool, wherein the spring loading is released by a small tap of a mallet, the spring selected and pre-loaded to deliver the exact amount of force desired over the exact travel distance desired. This force should be sufficient to push ramp formation 406 or 407 through locking ring 404 as previously described, but not so much as to injure the bone. In other embodiments, the spring may be released by a trigger mechanism instead of a mallet.
In yet other embodiments of the invention, other features similar in shape and position to the O-rings 441 and 443 may be provided. Those features may be formed of materials other than the material of the eyelet pin 403 and/or insert 405. Alternately, the features may be formed directly into the eyelet pin 403′ and/or insert 405′. The features should have rounded non-sharp shapes that help grip the suture without damaging it.
The sutures 46 that pass through the eyelet 409 pass through the middle of the hollow cylinder 901.
Referring now to
This configuration may provide stronger gripping of the sutures.
As shown in
The various different hollow cylinders 901, 909 and the various different configurations of the bore 415 and 417 in the eyelet pin 403 can be combined with each other in various permutations. For example the hollow cylinder 901 need not be a continuous ring and may have a circumferential gap (e.g., a split hollow cylinder) such as a rolled piece of thin metal or a roll pin.
In other embodiments, as already noted, the hollow cylinder need not be perfectly cylindrical, but can have an oblong or oval cross-section. In such embodiments, the eyelet can be rectangular so as to match the dimensions of an oval hollow cylinder (i.e., contacting it at four locations spaced 90° from each other around the circumference of the hollow cylinder) or it can have a square profile such that the hollow cylinder only contacts the eyelet at two location spaced 180° from each other around the circumference of the hollow cylinder.
In any of the embodiments discussed hereinabove in connection with the use of a hollow cylinder in the eyelet, it may be preferable to round out the proximal end of central pin 402 so as to avoid any sharp edges. This would help avoid the possibility of the central pain punching a hole through the hollow cylinder without substantially deforming it.
In this embodiment, the suture becomes locked in the device 400″ by means of the two eyelets 409 and 481 shifting in longitudinal position relative to each other. Particularly, in the open position, the eyelet 481 in the central pin in longitudinally aligned (and also rotationally aligned about the longitudinal axis) with the eyelet 409 in the eyelet pin so that one or more sutures may pass through the eyelets 409, 481 essentially as described in connection with the embodiment of
It now should be apparent that the reason the proximal bore 415″ is preferably slightly larger than the distal bore 417 proximal bore and the central pin 402′ is to provide clearance for the sutures between the two. It also should now be apparent that the reason the shoulder 435′ in the insert preferably is lower than in the embodiment of
This embodiment provides secure fixing of the suture(s) in the bone anchor device
In these types of embodiments, the bone anchor device could even possibly be delivered to the surgeon already in the closed state with or without one or more sutures already disposed in and passing through the eyelet.
As mentioned earlier, the exact configurations of the bone anchor devices are greatly variable, particularly within the parameters hereinabove described. Individual devices thus can be associated with particular predetermined features that will render them most effective for performing specific procedures. Also it should be noted that many of the features described in connection with individual embodiments of the present invention may be substituted into one or more of the other embodiments described herein, there being no limitation other than logic and physical limitations as to how the various features can be mixed and matched in a single device. The same is true for the surgical procedures disclosed herein, i.e., certain aspects of certain of the described surgical procedure embodiments may be used in other described surgical procedure embodiments described herein and/or may be performed in connection with other embodiments of the bone anchor devices and/or time fastener devices than those used in the exemplary embodiments described herein.
The procedures and medical devices as described can be altered in various further ways while still accomplishing the same results and the invention also covers such variations in the procedure.
It is submitted that, with the use of the present invention, the arthroscopic rotator cuff repair procedure is significantly facilitated by the use of the bone anchor device and/or the tissue fastener device of the present invention.
It must be understood in the above regard that one of the biggest challenges in arthroscopic surgery is knot tying. It is technically challenging and, insofar as the use of the bone anchor devices and/or the tissue fastening devices of the invention facilitate knotless suture fixation, the challenges associated with knot tying are largely overcome.
It must also be understood in the above regard that another challenge in arthroscopic surgery is suture management. It is technically challenging and, insofar as the use of the medical device of the invention facilitates effective suture management and loading of the suture anchor, the challenges associated with suture management are largely overcome.
Although other knotless fixation devices are already known, some of these require an anchor body to which a suture must be anchored to be located in a pilot hole. It is technically challenging to place an anchor body into the pilot hole, particularly because the hole often bleeds, obscuring the hole and, even if the hole does not bleed, recreating the exact angle that was used during the creation of the pilot hole is sometimes difficult. Placement of cannulas directly over a pilot hole also may create a suction effect dragging soft tissue over the hole, further obscuring it. It is thus often time-consuming and frustrating to locate the hole and correctly locate the bone anchor device in the hole. Incorrect angular location of an anchor device in a hole may occur from the precise angle of insertion necessary for good bone purchase and this may result in failure of some of the known knotless fixation devices. The procedures associated with the self drilling and self tapping bone anchor devices of the present invention as above described alleviate the problem of finding a pilot hole for a bone anchor device. Insofar as the use of other known knotless fixation devices and generally anchor devices may be associated also with various other problems and difficulties, either generally or specifically in relation to specific devices, the use of the medical device of the invention may serve also to at least alleviate these problems and difficulties.
It is also known that all presently available anchor designs are “buried” below the bone. This is done to prevent impingement of the head of the device with surrounding anatomy. Although the medical device of the invention may use a body with either no head or a lower profile head that allows the body to be buried below the bone, there are distinct advantages to using an anchor main body having a head that remains accessible externally of the humerus. As such, the anchor main body can be easily unscrewed from the humerus. With respect to some embodiments described herein, it is also possible to pull the eyelet pin from its anchor main body. The above may be necessary where a repair has failed and/or is not satisfactory and needs to be removed, where inadvertent suture dislodgement from the anchor device has occurred where irreversible tanglement of sutures has occurred, and/or where a suture knot comes loose. It is envisaged in this regard that bone anchor devices in accordance with the invention may be provided with anchor main bodies of larger diameter for placement in original holes formed by removed anchor main bodies to provide for optimal purchase strength of the device to bone. The use of the bone anchor device of the invention, therefore, reduces or eliminates the need, in the circumstances described above, for placing additional anchors within the limited space available for a repair, additional bone anchors may induce the risks of confluence of anchor holes, bone fracture and/or anchor pull-out. It must also be understood in relation to the use of known anchor devices, that at times the devices can be removed only by coring techniques that are cumbersome and time consuming and that often lead to significant bone loss that requires bone grafting. Bone grafting in itself may be associated with problems, thus rendering the use of the medical device of the invention significantly more appropriate in relation to many different procedures, when compared with the use of known anchoring techniques and anchoring devices, even known knotless fixation devices.
It is thus submitted that the known problems associated with the tying of sutures, the management of sutures and also the anchoring of sutures to the humerus, are largely alleviated, the same applying also in relation to other procedures with which the medical device of the invention can be conveniently used, either arthroscopically, or otherwise.
Having thus described a few particular embodiments of the invention, various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements as are made obvious by this disclosure are intended to be part of this description though not expressly stated herein, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only, and not limiting. The invention is limited only as defined in the following claims and equivalents thereto.
Huxel, Shawn T., Miller, Alan B., Levinsohn, David Gordon
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