|Publication number||USRE42526 E1|
|Application number||US 10/365,628|
|Publication date||Jul 5, 2011|
|Filing date||Jun 12, 2003|
|Priority date||Mar 18, 1998|
|Also published as||US6387129, US20010041937|
|Publication number||10365628, 365628, US RE42526 E1, US RE42526E1, US-E1-RE42526, USRE42526 E1, USRE42526E1|
|Inventors||Bernard Reiser, Reinhold Schmieding|
|Original Assignee||Arthrex, Inc.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (52), Non-Patent Citations (3), Referenced by (9), Classifications (20), Legal Events (1)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application claims the benefit of U.S. Provisional Application Ser. No. 60/078,391, filed Mar. 18, 1998, and is a continuation-in-part of U.S. patent application Ser. No. 09/243,995, filed Feb. 4, 1999, now abandoned, the disclosures of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to endosteal fixation of a ligament by device insertion and, more specifically, to methods and devices for bicortical tibial fixation of anterior cruciate ligament grafts.
2. Description of the Related Art
When a ligament becomes detached from a bone, surgery usually is required to reconstruct the ligament. Often, a substitute ligament or graft is secured into bone tunnels to facilitate incorporation and permanent attachment.
Various methods of graft attachment are known, including the use of interference screws to secure the graft against the walls of a tunnel drilled through the tibia and a socket formed in the femur. A strong graft attachment is obtained by using a metal interference screw to wedge a graft bone block to the wall of a graft tunnel formed through the bone, as disclosed in U.S. Pat. No. 5,211,647 to Schmieding. If a bioabsorbable interference screw is used, the graft can be wedged directly against the bone by the screw, without a bone component.
In either case, the graft usually is secured as close as possible to the normal ligament origin and insertion site, which are at the top of the tibial tunnel (the tibial plateau) and the entrance to the femoral socket in ACL reconstructions. The portion of the graft extending out the bottom of the tibia is ordinarily secured to the outside of the bone with a staple or using screw/washer fixation.
The above-described secondary fixation of the graft to the exterior surface of the tibia is disadvantageous in that it is subject to abrasion from external elements, and is generally less secure than internal fixation. Accordingly, a graft fixation technique is needed which provides increased fixation strength of the graft in the tibial tunnel, and improved healing of the tibial tunnel and associated tissue.
The present invention overcomes the disadvantages of the prior art and achieves the foregoing objectives by providing apparatus and methods for bicortical fixation of ligament grafts, whereby the graft is fixed at two cortical locations (“bicortical”) within the tibial tunnel using a pair of fixation devices. The invention advantageously improves fixation strength, and also minimizes the likelihood of damage to the graft and the bone tunnel during and after fixation, such as by preventing widening of the bone tunnel by graft motion. In addition, as described below, bicortical fixation improves the healing environment of the ligament graft.
The fixation strength of the graft is advantageously increased by engaging the graft against the denser, cortical bone at the ends of the tunnel. The fixation method and devices of the present invention preferably are designed to match the anatomy of the tibial tunnel, and to provide fixation at the original insertion point of the ligament. The fixation devices also are designed to minimize graft abrasion, while maximizing fixation strength.
Further, the preferred fixation methods and devices advantageously restrict blood loss from the fixation site to improve healing and graft incorporation. The preferred fixation modes advantageously plug both ends of the bone tunnel, and leave the internal bone tunnel cavity unobstructed between the plugged ends. Accordingly, the bone tunnel cavity, through which the graft passes, is allowed to fill with serous fluids to promote faster healing and enhance graft incorporation within the tunnel.
Various modes of fixation can be used in the present invention, including, for example, interference screws, wedges, expanding devices, and adhesives. Preferred alterative devices are those that securely engage the cortical wall of the tunnel, and preferably include threads, ridges, and/or other enhancements to maximize bone fixation.
Preferred methods and devices disclosed herein utilize interference screw fixation, although any other type of fixation device capable of being secured bicortically also could be used. Further, identical modes of fixation need not be used at both ends of the tunnel. Preferably, the mode of fixation also will at least substantially occlude both ends of the bone tunnel, resulting in the further advantage of an improved healing environment within the tunnel, as described further below.
According to a preferred embodiment using interference screw fixation, the interference screws used in the present invention preferably have a hex socket for receiving a hex-head screwdriver. The hex socket extends substantially the length of the screw to optimize the distribution of insertion torque along the length of the screws. In order to maintain wall thickness, the hex socket is tapered in correspondence with the tapered outer profile of the device. The taper also permits easy insertion of the hex driver (also tapered) into the fixation screw. A cannulated hex-head screwdriver is used for guide pin insertion methods.
The interference screws preferably are fully-threaded to maximize fixation strength within the tunnel. Preferably, the proximal screw (i.e., the screw closest to the joint) has a smooth, rounded tip profile so as to minimize abrasion with the graft. The distal screw (i.e., the screw farthest from the joint) has an angled back end so that it can be oriented substantially flush with the outer surface of the bone (e.g., the tibia) into which the screw has been installed. These and other features for minimizing graft abrasion and maximizing graft fixation also apply to the other modes of bicortical fixation envisioned by the present invention.
The fixation devices of the present invention, preferably interference screws, optimally are formed of a bioabsorbable material. Bioabsorbable materials known to those of skill in the art include poly-(L-lactic acid) (PLA), poly-(D,L-lactide), and poly glycolic acid (PGA), for example. Other bioabsorbable, non-metallic materials, especially those tailored for hardness, tensile strength, and compressive strength may be utilized. Other known biocompatible materials which could be used include plastics, titanium, titanium alloys, allograft bone, and inert bone substitute materials.
In the preferred method of ACL reconstruction of the present invention, the graft (preferably a hamstring tendon autograft or allograft) is secured femorally preferably by interference screw fixation in a socket formed through the tibial tunnel, as described, for example, in U.S. Pat. No. 5,320,626, the disclosure of which is incorporated herein by reference. The preferred femoral interference screw is inserted into the femoral socket, and has a rounded back end to prevent tissue damage after insertion. Other forms of femoral fixation also could be used.
Bicortical tibial fixation is provided by delivering the proximal fixation device to the inner opening of the tibial tunnel and installing the device to secure the ligament graft at the anatomical position on the tibial plateau. The distal device is delivered and installed to secure the graft within the tibial tunnel at the outer end of the tunnel. Prior to device insertion, the tunnel may be pre-tapped and/or dilated to enhance interference fixation.
A guide pin preferably is employed as necessary to guide the femoral interference screw and the proximal tibial interference screw during delivery and installation. For this reason, these two devices preferably are fully cannulated. The distal tibial screw, on the other hand, preferably is non-cannulated, to prevent blood from flowing from the tibial tunnel and into the surrounding tissue.
Femoral graft insertion and fixation can be achieved by various methods and devices known in the art, including the transverse, intraosseous pin and technique disclosed in allowed U.S. patent application Ser. No. 09/015,618, filed Jan. 29, 1998, or in U.S. Pat. No. 5,601,562, the disclosures of which are incorporated herein by reference.
Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings.
Screw 2 has a hexagonal socket 12 which tapers inwardly and extends from the back end substantially to the front end of the screw. At front end 10, a small, circular cannula 14 is formed for receiving a guide wire or pin. The smaller opening minimizes the amount of synovial fluid which can flow through the screw from the joint space into the interbone space of the tibial tunnel; synovial fluid can retard sharpie fiber growth into the graft within the bone tunnel.
Distal interference screw 20 has a hexagonal socket 28 which tapers inwardly and extends from the back end substantially to the front end of the screw. Front end 30 is not cannulated. Accordingly, the screw advantageously plugs the distal end of the tibial tunnel to prevent blood from flowing into the surrounding soft tissue.
Screw 40 has a tapered front end 48 terminating in a flat profile. Thread 44 extends substantially to the tip of the screw. Screw 40 is fully cannulated with a hexagonal socket 50 which tapers inwardly from the back end to the front end of the screw. At front end 48, the socket is formed to provide a substantially circular edge 52.
In the method of the present invention, once the graft has been accurately sized, a tunnel is created with a combination of drilling and/or cancellous bone dilation. The tibial tunnel angles proximally from the anterior portion of the tibia to the tibial plateau at an angle of approximately 50°. The tunnel preferably is about 50 mm in length. The tunnel preferably is drilled initially 1 or 2 mm smaller than the final diameter depending on the density of the bone. Subsequent dilation of the tunnel increases the level of fixation and insertion torque especially in the tibia where the cancellous bone is less dense. Preferably, the socket is formed by first drilling the tibial tunnel and then inserting a drill through the tibial tunnel and boring into the femur using a guide such as the guide disclosed in U.S. Pat. No. 5,320,626, the disclosure of which is incorporated herein by reference.
In the method of the present invention, graft 60 is first inserted into femoral socket 64. Before securing the graft into the femur, sutures on the graft preferably are tensioned on both ends while keeping the graft in position high in the femur. This dual tensioning helps prevent the graft from rotating during screw insertion. Transverse femoral pin 67 is then inserted through an arthroscopy portal to secure the graft in the femoral socket in accordance with the teachings of allowed application Ser. No. 09/015,618, previously incorporated by reference. Alternative methods include interference fixation using femoral interference screw 40 (
When employing femoral interference fixation, a femoral interference screw 40 is chosen with a diameter that ultimately matches or is larger than the graft/tunnel size (e.g., 8 mm graft/tunnel, 8 mm or 1 mm larger in diameter screw). The femoral screw preferably is 8 or 9 mm in diameter, and about 23 mm in length. For interference screw fixation within the tibia, screws are chosen which are 1 mm larger than the size used in the femur. The proximal tibial screw is preferably between about 10-25 mm in length, while the distal tibial screw is about 10-20 mm long overall. Prior to passing the graft, a tunnel notcher (Arthrex Part No. AR-1844) preferably is used to create an anterior-superior starting point for the implant.
Graft 60 is secured in the tibial tunnel 66 bicortically using interference screws 2 and 20, as follows: After the femoral interference screw 40 is installed, proximal tibial screw 2 is guided through tibial tunnel 66 over a guide pin (not shown) and turned or otherwise positioned at the tibial plateau using a cannulated inserter, such as the driver shown in
A preferred driver 70 for a bioabsorbable interference screw will be described with reference to
Advantageously, the present invention provides bicortical fixation within the tibial tunnel. The two device method maximizes tibial fixation by securing the soft tissue graft at the cortical bone layers at both the entrance and the exit of the tibial tunnel. The back end of the distal device is angled so that it closely approximates the angle of the distal tibial tunnel rim. The distal device is non-cannulated to prevent hematomas from being formed by blood flowing from the tibial tunnel into the surrounding soft tissue.
The proximal device can be a known device that is positioned up to the tibial plateau to maximize fixation in cortical bone. Preferably, the proximal device has a restricted cannula to minimize the flow of synovial fluid entering the tibial tunnel. The proximal device prevents the graft from moving side to side during cyclic loading, which enhances biological fixation and prevents tunnel widening. Cortical fixation at both ends of the tibial tunnel also advantageously results in the retention of blood between the devices, creating an advantageous environment for healing and incorporation of the graft.
Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. Therefore, the present invention is to be limited not by the specific disclosure herein, but only by the appended claims.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3953896 *||Sep 6, 1974||May 4, 1976||Richards Manufacturing Company, Inc.||Prosthetic ligament|
|US4301551 *||Jul 9, 1979||Nov 24, 1981||Ecole Polythechnique||Deformable high energy storage tension spring|
|US4456005 *||Sep 30, 1982||Jun 26, 1984||Lichty Terry K||External compression bone fixation device|
|US4463753 *||Sep 11, 1981||Aug 7, 1984||Gustilo Ramon B||Compression bone screw|
|US4605414||Jun 6, 1984||Aug 12, 1986||John Czajka||Reconstruction of a cruciate ligament|
|US4744793 *||Sep 6, 1985||May 17, 1988||Zimmer, Inc.||Prosthetic ligament connection assembly|
|US4755183 *||Feb 9, 1987||Jul 5, 1988||Pfizer Hospital Products Group, Inc.||Ligament prosthesis|
|US4772286 *||Feb 17, 1987||Sep 20, 1988||E. Marlowe Goble||Ligament attachment method and apparatus|
|US4828562 *||Feb 4, 1988||May 9, 1989||Pfizer Hospital Products Group, Inc.||Anterior cruciate ligament prosthesis|
|US4870957 *||Dec 27, 1988||Oct 3, 1989||Marlowe Goble E||Ligament anchor system|
|US4927421 *||May 15, 1989||May 22, 1990||Marlowe Goble E||Process of endosteal fixation of a ligament|
|US5004474 *||Nov 28, 1989||Apr 2, 1991||Baxter International Inc.||Prosthetic anterior cruciate ligament design|
|US5062843 *||Feb 7, 1990||Nov 5, 1991||Mahony Iii Thomas H||Interference fixation screw with integral instrumentation|
|US5108433 *||Feb 22, 1991||Apr 28, 1992||Minnesota Mining And Manufacturing Company||Tensioning means for prosthetic devices|
|US5116337||Jun 27, 1991||May 26, 1992||Johnson Lanny L||Fixation screw and method for ligament reconstruction|
|US5151104 *||Oct 26, 1989||Sep 29, 1992||Pfizer Hospital Products Group, Inc.||Self-locking joint connector|
|US5211647 *||Feb 19, 1992||May 18, 1993||Arthrex Inc.||Interference screw and cannulated sheath for endosteal fixation of ligaments|
|US5234430 *||Dec 18, 1991||Aug 10, 1993||Huebner Randall J||Orthopedic fixation screw and method|
|US5282802 *||Aug 19, 1991||Feb 1, 1994||Mahony Iii Thomas H||Method of securing a tendon graft with an interference fixation screw|
|US5364400 *||Jun 23, 1993||Nov 15, 1994||American Cyanamid Co.||Interference implant|
|US5370662 *||Jun 23, 1993||Dec 6, 1994||Kevin R. Stone||Suture anchor assembly|
|US5397357 *||Jan 26, 1994||Mar 14, 1995||Arthrex, Inc.||Method for preparing a bone-tendon-bone core graft|
|US5423819||Aug 17, 1992||Jun 13, 1995||American Cyanamid Company||Screw and driver for securing a bone block|
|US5456685||Feb 14, 1994||Oct 10, 1995||Smith & Nephew Dyonics, Inc.||Interference screw having a tapered back root|
|US5470334 *||Jun 22, 1992||Nov 28, 1995||Linvatec Corporation||Bioabsorbable interference bone fixation screw|
|US5496326||Oct 24, 1994||Mar 5, 1996||Johnson; Lanny L.||Fixation screw and method for ligament reconstruction|
|US5505731 *||Aug 26, 1994||Apr 9, 1996||Tornier Sa||Screw for lumbar-sacral fixator|
|US5507812 *||Apr 26, 1994||Apr 16, 1996||Moore; David E.||Modular prosthetic ligament|
|US5562669 *||Jan 13, 1994||Oct 8, 1996||Mcguire; David A.||Cruciate ligament reconstruction with tibial drill guide|
|US5562671 *||Sep 26, 1994||Oct 8, 1996||Depuy Inc.||Ligament replacement cross pinning method|
|US5632748||Dec 22, 1994||May 27, 1997||Linvatec Corporation||Endosteal anchoring device for urging a ligament against a bone surface|
|US5871504||Oct 21, 1997||Feb 16, 1999||Eaton; Katulle Koco||Anchor assembly and method for securing ligaments to bone|
|US5895425 *||Feb 6, 1998||Apr 20, 1999||Arthrex, Inc.||Bone implant|
|US5899938 *||Nov 27, 1996||May 4, 1999||Joseph H. Sklar||Graft ligament anchor and method for attaching a graft ligament to a bone|
|US5925048 *||Mar 13, 1998||Jul 20, 1999||Osteomed||Bone screw|
|US5957924 *||May 22, 1997||Sep 28, 1999||Bionx Implants Oy||Installation tool for suture anchor|
|US5961520 *||Mar 27, 1997||Oct 5, 1999||Beck, Jr.; Charles L.||Endosteal anchoring device for urging a ligament against a bone surface|
|US5968045 *||Oct 14, 1997||Oct 19, 1999||Frazier; John K.||Intra-articular tendon sling fixation screw|
|US5993486 *||Aug 4, 1998||Nov 30, 1999||Senko Medical Instrument Mfg. Co., Ltd.||Artificial ligament|
|US6001101 *||Jan 13, 1997||Dec 14, 1999||Depuy France||Screw device with threaded head for permitting the coaptation of two bone fragments|
|US6019759 *||Dec 6, 1996||Feb 1, 2000||Rogozinski; Chaim||Multi-Directional fasteners or attachment devices for spinal implant elements|
|US6099568 *||Mar 3, 1998||Aug 8, 2000||Linvatec Corporation||ACL graft fixation device and method|
|US6123710 *||Apr 11, 1996||Sep 26, 2000||Smith & Nephew, Inc.||Process and article for knee reconstruction|
|US6221107 *||Aug 3, 1998||Apr 24, 2001||Mark E. Steiner||Ligament fixation device and method|
|US6235057 *||Feb 19, 1997||May 22, 2001||Smith & Nephew, Inc.||Method for soft tissue reconstruction|
|US6264694 *||Feb 11, 1999||Jul 24, 2001||Linvatec Corporation||Soft tissue graft fixation device and method|
|US6616694 *||Nov 21, 1997||Sep 9, 2003||Ethicon, Inc.||Apparatus for anchoring autologous or artificial tendon grafts in bone|
|US6629977 *||Nov 15, 2000||Oct 7, 2003||Arthrex, Inc.||Tapered bioabsorbable interference screw and method for endosteal fixation of ligaments|
|US6953463 *||Oct 12, 2001||Oct 11, 2005||Hs West Investments, Llc||Interference screws having increased proximal diameter|
|US7083647 *||Nov 17, 2000||Aug 1, 2006||Sklar Joseph H||Fixation screw, graft ligament anchor assembly, and method for securing a graft ligament in a bone tunnel|
|US7235078 *||Nov 26, 2002||Jun 26, 2007||Hs West Investments Llc||Protective devices for use with angled interference screws|
|USRE34871 *||May 21, 1992||Mar 7, 1995||Mcguire; David A.||Process of endosteal fixation of a ligament|
|1||"Orthopedic Screw Machined in One Step", Tooling and Production, Apr. 1994.|
|2||Mark H. Gonzalez, M.D. and Robert F. Hall, Jr. "Intramedullary Fixation of Metacarpal and Proximal Phalangeal Fractures of the Hand", pp. 47-54, Clinical Orthopaedics and Related Research, No. 327, 1996.|
|3||Thomas A. Russell, et al. "Mechanical Characterization of Femoral Interlocking Intramedullary Nailing Systems", pp. 332-340, Journal of Orthopaedic Trauma, Vol. 5, No. 3, 1991.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US8226716 *||Jul 24, 2012||Depuy Mitek, Inc.||Method and apparatus for fixing a graft in a bone tunnel|
|US8579975 *||Feb 14, 2011||Nov 12, 2013||Imds Corporation||Double bundle ACL repair|
|US8591580||Jun 5, 2012||Nov 26, 2013||Depuy Mitek, Llc||Folded ligament graft|
|US8617241 *||Mar 31, 2010||Dec 31, 2013||Imds Corporation||Double bundle ACL repair|
|US8968402||Oct 18, 2012||Mar 3, 2015||Arthrocare Corporation||ACL implants, instruments, and methods|
|US9216079||Aug 22, 2013||Dec 22, 2015||Imds Llc||Double bundle ACL repair|
|US9314332||Oct 18, 2013||Apr 19, 2016||Depuy Mitek, Llc||Method and apparatus for fixing a graft in a bone tunnel|
|US20100249930 *||Sep 30, 2010||Medicinelodge, Inc. Dba Imds Co-Innovation||Double bundle acl repair|
|US20150100121 *||Sep 30, 2014||Apr 9, 2015||The Trustees Of Columbia University In The City Of New York||Biomimmetic nanofiber scaffold for soft tissue and soft tissue-to-bone repair, augmentation and replacement|
|International Classification||A61F2/08, A61B17/88, A61B17/86|
|Cooperative Classification||Y10S606/916, Y10S606/908, A61F2002/0858, A61F2002/0841, A61B17/888, A61F2002/0882, A61B17/8645, A61B17/8615, A61F2/0805, A61B17/864, A61F2/0811|
|European Classification||A61B17/86G, A61F2/08F, A61F2/08D, A61B17/88S2C, A61B17/86A2C|