621 results about "Femur" patented technology

A self-centering meniscal prosthesis device suitable for minimally invasive, surgical implantation into the cavity between a femoral condyle and the corresponding tibial plateau is composed of a hard, high modulus material shaped such that the contour of the device and the natural articulation of the knee exerts a restoring force on the free-floating device.

A replacement device for resurfacing a joint surface of a femur and a method of making and installing such a device is provided. The custom replacement device is designed to substantially fit the trochlear groove surface, of an individual femur. Thereby creating a "customized" replacement device for that individual femur and maintaining the original kinematics of the joint. The replacement device may be defined by four boundary points, and a first and a second surface. The first of four points is 3 to 5 mm from the point of attachment of the anterior cruciate ligament to the femur. The second point is near the bottom edge of the end of the natural articulatar cartilage. The third point is at the top ridge of the right condyle and the fourth point at the top ridge of the left condyle of the femur. The top surface is designed so as to maintain centrally directed tracking of the patella perpendicular to the plane established by the distal end of the femoral condyles and aligned with the center of the femoral head.

A method of preparing an interpositional implant suitable for a knee. The method includes determining a three-dimensional shape of a tibial surface of the knee. An implant is produced having a superior surface and an inferior surface, with the superior surface adapted to be positioned against a femoral condyle of the knee, and the inferior surface adapted to be positioned upon the tibial surface of the knee, The inferior surface conforms to the three-dimensional shape of the tibial surface. The implant may be inserted into the knee without making surgical cuts on the tibial surface. The tibial surface may include cartilage, or cartilage and bone.

A method of minimally invasive unicompartmental knee replacement includes accessing a knee through a minimal incision, forming a planar surface along a tibial plateau of the knee, forming a planar posterior surface along a posterior aspect of the corresponding femoral condyle, resurfacing a distal aspect of the femoral condyle to form a resurfaced area having a curved portion, implanting a prosthetic tibial component on the planar surface along the tibial plateau and implanting a prosthetic femoral component on the prepared surface of the femoral condyle formed by the planar posterior surface and the resurfaced area. The curved portion of the resurfaced area has an anterior-posterior curvature corresponding to a fixation surface of the prosthetic femoral component. Prior to implantation, the femur and tibia are prepared to receive fixation structure of the femoral and tibial components.

Novel cutting guides and surgical methods for use in knee arthroplasty are described. Embodiments of the inventive cutting guide apparatus include fixed and adjustable cutting guide blocks having a series of slots designed to accommodate a cutting saw. The cutting guides and surgical method are designed to allow for the provision of all desired surgical cuts upon the distal end of the femur, for subsequent implantation of a prosthesis thereto, without having to remove the cutting guide block.

Methods and apparatus using a surgical navigation system to position the femoral component of a prosthetic hip during hip joint replacement surgery without separately affixing a marker to the femur. The navigation system acquires the center of rotation of the hip joint as well as at least one point on the femur in the pelvic frame of reference. From these two points, the navigation system calculates the position and length of a first line between the center of rotation of the hip joint and the point on the femur. Optionally, a second point on the femur that is not on the first line is palpated. The system can calculate the position and length of a second line that is perpendicular to the first line and that runs from the first line to the second palpated point on the femur. The prosthetic cup is implanted and its center of rotation is recorded. A tool for forming the bore within which the stem of the femoral implant component will be placed is tracked by the navigation system. While the tool is fixed to the femur, the surgeon re-palpates the same point(s) on the femur that were previously palpated. The navigation system calculates the position and length of a first line between the center of rotation of the prosthetic cup and the re-palpated first point. If a second point on the femur was re-palpated, the navigation system also calculates the position and length of a perpendicular line between the first line and the second point. The surgical navigation system uses this information to calculate and display to the surgeon relevant information about the surgery, such as change in the patient's leg length and/or medialization/lateralization of the joint.

The invention relates to a knee joint prosthesis having a bearing and a biologic ligament for replacing the articulating knee portion of a femur and a tibia. The knee joint prosthesis includes a femoral component, a tibial component, a bearing member, and a biologic ligament. The femoral component includes a first femoral bearing surface and a second femoral bearing surface. The tibial component includes a tibial bearing surface. The bearing member includes a first bearing surface which is operable to articulate with the first femoral bearing surface, a second bearing surface which is operable to articulate with the second femoral bearing surface and a third bearing surface which is operable to articulate with the tibial bearing surface. The biologic ligament is coupled to both the tibia and the femur to prevent the knee joint from dislocating and guiding the femoral component along a desired path during extension and flexion.

There is provided a method and system for determining a distal cut thickness and posterior cut thickness for a femur in a knee replacement operation, the method comprising: performing a tibial cut on a tibia; performing soft tissue balancing based on a desired limb alignment; measuring an extension gap between the femur and said tibial cut while in extension; measuring a flexion gap between the femur and the tibial cut while in flexion; calculating a distal cut thickness and a posterior cut thickness for the femur using the extension gap and the flexion gap and taking into account a distal thickness and posterior thickness of a femoral implant; and performing said femoral cut according to the distal cut thickness and posterior cut thickness.

The invention relates to a knee joint prosthesis for replacing the articulating knee portion of a femur and a tibia. The knee joint prosthesis includes a femoral component, a tibial component, a bearing member, a guide post and a mechanically reconstructed ligament. The femoral component includes a first femoral bearing surface and a second femoral bearing surface. The tibial component includes a tibial bearing surface. The bearing member includes a first bearing surface which is operable to articulate with the first femoral bearing surface, a second bearing surface which is operable to articulate with the second femoral bearing surface and a third bearing surface which is operable to articulate with the tibial bearing surface. The guide post extends from the tibial component. The mechanically reconstructed ligament is coupled to both the tibial component and the femoral component to prevent the knee joints from dislocating and guiding the femoral component along a desired path during extension and flexion.

A modular knee implant system allows a surgeon to select between several different styles of distal femoral implant components and several different styles of stem extensions while also allowing for use of a metaphyseal component. The metaphyseal component can be a universal one that is usable with all of the styles of distal femoral implant components through use of an adapter. A second adapter allows for use of stem extensions with different types of connectors with the metaphyseal component. A separate metaphyseal component could also be provided with a distal Morse taper post to mate with a distal femoral component having a proximal Morse taper bore. The metaphyseal component may have an outer surface that is configured to maximize contact area with the patient's bone, and may have a surface finish over a substantial part of its overall length that is conducive to bone ingrowth.

A knee replacement system provides a knee implant that may be used to more accurately replicate the diameter of a natural knee. In one embodiment, a patellofemoral component is connected to the posterior portion of a condylar component by screws that pass through the femur allowing the patellofemoral component and the condylar component to be torqued against opposing sides of the femur. Two additional screws are used to connect the patellofemoral component to an anterior portion of the condylar component. A gap may be left between the patellofemoral component and the anterior portion of the condylar component if needed to provide precise replication of the diameter of the natural knee from the patellofemoral component to the condylar component.

The present invention has multiple aspects relating to assembled self fixing bone-tendon-bone (BTB) grafts and BTB implants. A preferred application in which self fixing assembled bone-tendon-bone (BTB) grafts and implants of the present technology can be used is for ACL repairs in a human patient. In one embodiment, a self fixing BTB graft is characterized by the presence of threads along at least a portion of the exterior surface of one or both bone blocks. In another embodiment, a self fixing assembled bone-tendon-bone implant comprises a removable tendon tensioner which imparts a predetermined tension on the tendon of the BTB graft. In this embodiment, the tensioner can be narrower than the diameter of the bone blocks or can be threaded such that the threads are continuous with the threads of at least one of the bone blocks. The threads facilitate the simultaneous implantation of the leading and trailing bone blocks of the BTB graft in tapped (threaded) holes in the tibia and the femur of a recipient patient. The tensioner maintains the tension on the tendon and the spacing between the bone blocks until the leading bone block is fixed (threaded) in the tapped hole in the femur and the trailing bone block is fixed (threaded) into the tapped tibial bone tunnel. Once the bone blocks are substantially in their fixed positions, the tensioner is removed arthroscopically in the joint space between the tibia and the femur.

A soft tissue fixation system, most typically applicable to orthopedic joint repairs, such as anterior cruciate ligament (ACL) knee repair procedures, comprises an implant which is placeable in a tunnel disposed in a portion of bone, wherein the tunnel is defined by walls comprised of bone. A first member is deployable outwardly to engage the tunnel walls for anchoring the implant in place in the tunnel, and a second member is deployable outwardly to engage tissue material to be fixed within the tunnel. The second member also functions to move the tissue material outwardly into contact with the tunnel walls to promote tendon-bone fixation. Extra graft length is eliminated by compression of the tendon against the bone at the aperture of the femoral tunnel, which more closely replicates the native ACL and increases graft stiffness. The inventive device provides high fixation of tendon to bone and active tendon-bone compression. Graft strength has been found to be greater than 1,000 N (Newtons), which is desirable for ACL reconstruction systems.

A method of preparing a knee joint for receiving a unicondylar knee implant includes preparing a first seating surface at a proximal end of a tibia, and providing a combination bur template and spacer block, the bur template having an upper end, a lower end and a curved surface extending between the upper and lower ends thereof that is adapted to conform to a femoral condyle of a femur and the spacer block extending from the lower end of the bur template and having top and bottom surfaces. The method includes flexing the knee joint so that the prepared first seating surface at the proximal end of the tibia opposes a posterior region of the femoral condyle and inserting the combination bur template and spacer block into the knee joint so that the top surface of the spacer block engages the posterior region of the femoral condyle and the bottom surface of the spacer block engages the first seating surface at the proximal end of the tibia. While the spacer block is maintained between the femur and the tibia, the knee joint is extended until the curved surface of the bur template engages the femoral condyle of the femur. The bur template is anchored to the femur and used to guide burring of the femoral condyle for preparing a second seating surface on the femur. After burring the distal end of the femoral condyle, the posterior region of the femoral condyle is resected.

A system for preparing a trochlear region of a resected femur is disclosed. The system includes a reamer guide and a reamer. The reamer guide has a first arcuate portion, a second arcuate portion, a wall, a protrusion connected to the wall, a leg connected to one of the first or second arcuate portion, and a distal tip portion connected to the leg. The reamer is adapted to rotatably connect to the distal tip portion, and the reamer has a first end portion, a second end portion, and one or more flutes.

An all-inside double-socket ACL reconstruction technique, according to which a femoral socket and a closed tibial socket are provided to accommodate retrograde fixation of at least one graft (for example, a semitendonosus allograft) within the sockets. The closed tibial socket is formed by using a retrograde drill device provided with a retrograde drill cutter detachable from a retrograde drill guide pin. The femoral socket may be formed by the retrograde drill method or by a conventional method, and may be carried out before or after the formation of the tibial socket. The graft is secured in the knee by employing a transversal implant, or by employing an interference screw, and/or a continuous loop/button construct.

A system is disclosed for repairing and reconstructing an injured anterior cruciate ligament (ACL); This system may be used irrespective of the type of patient or the ACL graft selected. Means for performing single or multiple bundle reconstruction, primary ACL repair and physeal-sparing ACL reconstruction are disclosed. A guide for inside-out creation of a femoral tunnel independent of the tibial tunnel is also disclosed, as well as a series of implant options for tibial and femoral fixation of any bone-soft-tissue composite or soft-tissue-only graft.

A femoral component (100) for a total knee joint replacement has a modular structure including a number of segments (102, 112), each of the segments (102, 112) having a femoral fixation surface (104, 114) for attachment to the distal end of a femur and at least one assembly surface (108) for joining with an adjacent segment (102, 112) of the modular femoral component (100). The assembly surfaces (108) are generally planar and arranged to be oriented generally in a plane extending in a proximal-distal direction and in an anterior-posterior direction when the femoral fixation surface (104, 114) is positioned on the distal end of the femur. Although the assembly surfaces (108) are generally planar, they may be shaped or provided with complementary structures (120) to assure self-alignment when the segments (102, 112) are assembled.

A system and method for knee arthroplasty procedures, using a novel leg rotation fixture to enable the leg mechanical axis, the tibia and the femur to be mutually disposed such that the load bearing, mechanical axis of the leg runs through the center of the knee joint. A measurement gauge is provided for mounting on the tibia and for aligning a baseplate in a known position on the tibia. This baseplate supports an X-ray target plate in a known position relative to the tibia, used in determining the mechanical axis, and an optional surgical robot, used to perform tibial and femoral cuts. The position of the femur relative to the robot may be determined from X-ray imaging of the pelvic region after attachment to the baseplate of an additional target extending to the pelvic region. The system enables improvement in the accuracy of knee arthroplasty procedures.

A knee prosthetic including a tibial component defining medial and lateral concavities shaped to receive medial and lateral femoral condyles of the femur. The concavities have first portions for contact with the condyles during normal knee flexion and second portions for contact with the condyles during deep, or high, knee flexion. The medial concavity can include a conforming boundary that encompasses at least the first and second portions, wherein an area inside the conforming boundary has a generally flat surface. The flat surface allows the medial femoral condyle to slide and rotate posteriorly during high knee flexion. The conforming boundary can have a generally triangular shape with an apex extending anteriorly and a relatively wider base extending posteriorly, wherein the apex includes the first portion and the base includes the second portion. The relatively wider base portion advantageously allows additional area for posteriorly directed articulating contact during high knee flexion.

A method for treating a patient suffering from osteoarthritis and an internal brace for distraction arthroplasty including femoral and tibial components which can be fixed to a patient's femur and tibia and which in combination distract or separate the knee joint without substantially hindering mobility of the knee.

A combination of a first assembly for guiding resection of a femur and tibia of a knee joint and a second assembly including femoral and tibial knee components. The combination of the first assembly and the second assembly provides optimal placement and positioning of the femoral and tibial knee components to achieve near-normal knee kinematics and tension. The preparation for and placement of the prosthetic knee components provides medial-pivoting kinematics mimicking that of the natural knee thereby promoting improved outcome for the patient.

A bone plate(s) of complex form is provided, particularly suited to tibial plateau-leveling osteotomy and a distal femoral osteotomy. The bone plate has a main longitudinal axis, a bone-contacting bottom side (not shown) and a top side with at least three sets of overlapping holes which communicate through the plate from the top to the bottom side. The sets of overlapping holes define threaded apertures having multifaceted surfaces. When applied to a bone, two sets of such overlapping holes are located so as to lie on opposite sides of an osteotomy site and on the tibial plate; a third is aligned at approximately 60 degrees with the longitudinal axis. The configuration of this complex bone plate vary, depending on the physiology of the patient. An object of the invention is to provide an orthopaedic surgeon greater flexibility of choice in that a threaded peg providing secure fixing can be positioned at any interval along the bone plate, including at its extreme ends or on its elbow.

According to the invention, the system enables a preoperative study to be carried out wherein the tibia and/or femur is modelled on a computer (6) in 3D, the ideal cutting plane is defined and the position of the resection instruments (1, 2, 3) used to cut the bone is modelled. Additionally, according to the invention, the system enables redefinition of the ideal cutting plane and the positioning and orientation of the resection instruments (1, 2, 3) on the tibia and/or femur, in such a manner that the plane of the slot (4) of the cutting guide (3) through which the cutting tool is introduced coincides with the ideal cutting plane.

A ligament and bone conserving prosthesis for total knee resurfacing includes a distal femoral component which resurfaces the weight bearing portions of both femoral condyles and the trochlear groove. The prosthesis also includes implants to independently resurface the medial and lateral tibial plateaus in an inset manner. Also disclosed are apparatus and methods for performing the total knee resurfacing utilizing a minimally invasive, bone and ligament conserving manner.

A dynamic spacer is provided for measuring flexion-extension gap during total knee arthroplasty. The dynamic spacer is an improved surgical instrumentation system that it easy to use, simple in construction, and accurately measures flexion-extension gaps under repeatable soft tissue tension. The dynamic spacer generally comprises a first planar member having a lower tissue engaging surface, a second planar member having an upper tissue engaging surface. A tensioner is disposed between the first planar member and the second planar member for applying a tensile force acting upon the first and second planar members. The tensioner is fixedly attached to the first and second planar members, such that the first planar member is held substantially parallel to the second planar member in the absence of compressive load. The dynamic spacer allows for accurately measuring flexion-extension gaps and angular deviation in flexion indicating the appropriateness of femoral rotation.

An apparatus in a total knee replacement and arthroplasty operation for measuring a joint gap and ligament balance between a osteotomized surface at a femoral distal end and a osteotomized surface at a tibial proximal end. The apparatus is provided with a base 10, from which an engaging plate 14 extends by way of an arm, so that the engaging plate 14 contacts with the osteotomized surface at the tibial proximal end. A moving body 18 is vertically movably connected to the base 10, from which moving body 18 an arm 20 extends, to which arm a supporting plate 22 is rotatably mounted about a central axis. The supporting plate 22 has, at its top surface, a projected portion 48. to which an auxiliary guiding piece 50 is connected under a snap like fitted manner. A femoral component 52 is mounted, at its groove portion 54, to the osteotomized surface at the femoral distal end. The engaging plate 14 as well as the supporting plate 22 are under an offset arrangement with respect to the base and moving body, respectively.

A system and method for measuring biomechanical parameters of a knee prior to total knee replacement (TKR) surgery includes a plurality of microsensors removably attached to the femur, tibia and patella; at least one sensor communicating with the plurality of microsensors; a navigation system coupled to the at least one sensor; an imaging system coupled to the navigation system for performing imaging of the joint; and at least one display for displaying imaging and tracking data.

An artificial knee joint including a femoral component and a tibial component which are in relation of making relative rotation, in which the tibial component has a post that has an outwardly curving posterior surface and is disposed approximately in the longitudinal center between the articular surfaces so that the post is inside an intercondylar groove that is between the medial and lateral condyles and extends from the posterior end to the anterior end of the femoral component; and the femoral component has a cam that is disposed at the posterior portion of the intercondylar groove and comes into contact with the posterior surface of the post when the above-described rotation proceeds; and the post and the cam are shaped so that the femoral component is turned outwardly when the cam comes into contact with the post as a result of the rotation and as the rotation proceeds.

A knee replacement system includes a proximal tibial posterior camming portion defined by a first radius of curvature with a first origin in a first medio-lateral plane, a distal tibial posterior camming portion defined by a second radius of curvature with a second origin in a second medio-lateral plane, an anterior femoral camming portion of a posterior cam defined by a third radius of curvature with a third origin in the first medio-lateral plane, and a posterior femoral camming portion of the posterior cam and defined by a fourth radius of curvature with a fourth origin in the second medio-lateral plane, wherein the second origin is closer to the lateral tibial portion than the first origin, or the fourth origin is closer to the medial femoral portion than the third origin.