384 results about "Femoral component" patented technology

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 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.

Instrumentation for use in minimally invasive unicompartmental knee replacement includes a tibial cutting guide for establishing a planar surface along a tibial plateau and a tibial stylus having an anatomic contour for controlling the depth of the planar surface along the tibial plateau. The instrumentation further comprises a posterior resection block for preparing a posterior femoral resection, with a forward portion of the posterior resection block having a configuration corresponding to the configuration of a prosthetic femoral component. Instrumentation comprising a resection block and a resurfacing guide are provided for surgically preparing a femoral condyle to receive a prosthetic femoral component. The instrumentation further includes a resurfacing guide and a resurfacing instrument for resurfacing a femoral condyle to a controlled depth. Instrumentation is provided for intramedullary alignment of femoral instruments. Also, instrumentation is provided for preparing the femur and tibia to receive fixation structure of prosthetic femoral and tibial components.

Knee prostheses featuring components that more faithfully replicate the structure and function of the human knee joint in order to provide, among other benefits: greater flexion of the knee in a more natural way by promoting or at least accommodating internal tibial rotation in a controlled way, replication of the natural screw home mechanism, and controlled articulation of the tibia and femur respective to each other in a more natural way. In a preferred embodiment, such prostheses include an insert component disposed between a femoral component and a tibial component, the insert component preferably featuring among other things a reversely contoured postereolateral bearing surface that helps impart internal rotation to the tibia as the knee flexes. Other surfaces can also be specially shaped to achieve similar results, preferably using iterative automated techniques that allow testing and iterative design taking into account a manageable set of major forces acting on the knee during normal functioning, together with information that is known about natural knee joint kinetics and kinematics.

A method is provided for performing a total knee arthroplasty. The method includes making a primary incision near a knee joint of a patient and resecting medial and lateral condyles of the femur of the leg to create at least one femoral cut surface. The resecting step is performed without dislocating the knee joint. The method also includes balancing various ligament tensions to obtain desired tension and moving a femoral component of a total knee implant through the primary incision. The method further includes positioning the femoral component with respect to the at least one femoral cut surface.

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.

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.

Disclosed is a device and method of bicompartmental arthroplasty of the knee. The device permits arthroplasty of the medial or lateral and patellofemoral compartments of the knee while leaving the opposite compartments and the anterior and posterior cruciate ligaments intact. The device provides a femoral prosthesis component that includes a trochlear surface and a tibial prosthesis component which can be secured to the tibia. The femoral component is essentially “u” shaped having an anterior leg upon which the trochlear surface is positioned and a posterior leg which engages the posterior surface of the distal end of the femur. The femoral component also has a convex articulating surface which engages a concave articulating surface of the tibial prosthesis component to approximate the articulation of a healthy knee.

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 two-thirds prosthetic arthroplasty having a trochlear groove, a patello-femoral component, and either a lateral condyle or a medial condyle. The arthroplasty may be configured to be a prosthetic for either a right or left knee. The condyle and patello-femoral component are separated by a modified intercondylar notch that is blended to avoid protrusions or sharp angles. The prosthetic arthroplasty is inserted after preoperative MRI mapping of articular cartilage damage. The prosthetic arthroplasty may be cemented during surgery and the two-thirds design of the present invention obviates the problem of cement retrieval from remote parts of the prosthesis.

A prosthetic implant for replacing a facet joint of a spinal motion segment includes a generally conical superior component adapted to be implanted at a surgically prepared site on a lower articular process of a cephalad vertebra of a spinal motion segment, and a cup-shaped inferior component adapted to be implanted at a surgically prepared site on a superior articular process of a caudad vertebra of the spinal motion segment.

An acetabular shell liner having a variable rim surface geometry, which improves range of motion of the femoral component within the liner and decreases the incidence of dislocation and subluxation, and methods of making and using the acetabular shell liner. Prosthetic devices, more particularly hip joint prostheses, containing the acetabular shell liner having a variable rim surface geometry are also provided.

An orthopedic implant device and method is disclosed. Specifically, a knee mold system is disclosed, including elastic tibial and femoral molds, each of which may be configured and dimensioned as a unitary mold for in situ placement during a surgical procedure. Each mold may be manufactured from an elastic material that may be disposable. The tibial mold may further comprise a sidewall forming a cavity, markings for relative depth measurement, and depth rings for use as a guide for scoring, cutting, and / or trimming and tearing away an excess portion of the tibial mold. The femoral mold may further comprise a sidewall defining a cavity, two legs extending from a body of the femoral mold for forming the artificial condyles, and an eyelet for aiding in placement and removal of the femoral mold. The resulting prosthetic tibial and femoral components may form an articulation surface that mimics, at least in part, the natural articulation surface of the knee.

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.

Numerous joint replacement implant embodiments including a total knee replacement implant including a femoral component (102) having a wheel (104); and a tibial component (106) including a shock-adsorbing component with a piston assembly (110) and spring (112). Said implants contain a cushioning or shock-absorbing member to dampen axial loads and other forces. In many embodiments, fluid is force rapidly from the device wherein compression and dampening is achieved by valves or other pathways that allow for a slower return of the fluid back into the implant as the pressure is relieved.

Disclosed is a device and method of bicompartmental arthroplasty of the knee. The device permits arthroplasty of the medial or lateral and patellofemoral compartments of the knee while leaving the opposite compartments and the anterior and posterior cruciate ligaments intact. The device provides a femoral prosthesis component that includes a trochlear surface and a tibial prosthesis component which can be secured to the tibia. The femoral component is essentially “u” shaped having an anterior leg upon which the trochlear surface is positioned and a posterior leg which engages the posterior surface of the distal end of the femur. The femoral component also has a convex articulating surface which engages a concave articulating surface of the tibial prosthesis component to approximate the articulation of a healthy knee. The patellar prosthesis is applied to the posterior surface of the patella and articulates with the trochlear exterior surface of the femur.

A plurality of knee joint prostheses comprise a first femoral implant and a second femoral implant. The first femoral implant has a first maximum interior anterior to posterior dimension, a first maximum overall exterior anterior to posterior dimension, a first lateral condyle, and a first medial condyle. The second femoral implant has a second maximum interior anterior to posterior dimension that is substantially the same as the first maximum interior anterior to posterior dimension, a second maximum overall exterior anterior to posterior dimension that is different than the first maximum overall exterior anterior to posterior dimension, a second lateral condyle having a medial to lateral dimension that is substantially the same as a medial to lateral dimension of the first lateral condyle, and a second medial condyle having a medial to lateral dimension that is different than a medial to lateral dimension of the first medial condyle.

A knee prosthesis is provided that allows for increased flexion. The knee prosthesis includes (a) a femoral component adapted to fit on a distal end of the femur which includes a lateral condylar structure and a medial condylar structure and (b) an intermediate structure configured to cooperate with a femoral component of a knee prosthesis. The intermediate structure includes at least one surface for contacting the femoral component and a transition of a sagittal curvature of the at least one contact surface from a concave surface into a convex surface at the contact interface of the femoral component and the intermediate structure when the knee is flexed at approximately 120° to 140°. The knee prosthesis minimizes impingement on the femoral posterior cortex in deep flexion, increases the dislocation safety factor and allows for easier reengagement of the articular surface should the femoral component externally rotate off of the tibial plateau.

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.

In a knee prosthesis, the condylar surfaces of a femoral component engage corresponding articular surfaces of a tibial component along prescribed tracks of predetermined curvature which enable relative rotation between the femoral component and the tibial component about a longitudinal axis during articulation of the knee prosthesis, and at least the condylar surfaces or the articular surfaces are flared in a direction away from corresponding articular surfaces or condylar surfaces along engaged posterior and anterior portions of the condylar surfaces and articular surfaces to provide an increased area of contact in deep flexion and in extended hyperextension for reducing contact stresses and concomitant wear while militating against unwanted distraction of the knee prosthesis. In addition, the radius of curvature of the condylar surfaces is reduced along posterior portions of the condylar surfaces to further avoid distraction of the knee prosthesis in deep flexion, thereby enabling deep flexion with greater ease and without excessive contact forces between the femoral component and the tibial component in deep flexion.

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.

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.

An apparatus for resecting the distal face of either the left or right femur at a predetermined valgus angle relative to the patient's intramedullary canal prior to implanting the femoral component of a total knee prosthesis. The apparatus has a distal elongate sword having a longitudinal axis and being adapted for insertion into the intramedullary canal of the femur. A proximal handle is connected to and has a longitudinal axis coaxial with the sword. A base cartridge is fixed intermediate the sword and handle and has an axial passage extending therethrough. A face plate is fixed at the distal end of the base cartridge and is adapted to abut the face of the natural distal femur. The face plate is oriented at the predetermined valgus angle relative to the longitudinal axis of the sword. A cutting jig connects to the base cartridge. The cutting jig has a guide plate with at least one blade slot adapted to receive and guide a cutting blade, and a bracket that supports the guide plate and detachably engages the axial passage and orients the at least one blade slot at the predetermined valgus angle relative to the longitudinal axis.