Abstract:
Implant with multi-directional pivoting has a first component including a first articular surface and a fore-to-aft and side-to-side rotation device; and a second component including a second articular surface for mating with the first surface and a rotation device receptacle. The first component can be mated to the second through cooperation of the rotation device and receptacle, and the first component can cooperate with the second in articular surface contact. The joint may be a knee prosthesis comprising first femoral and second tibial components, with the first surface a femoral condylar surface and the second surface a tibial condylar surface. Therein, the fore-to-aft component can be considered flexion, with the side-to-side component considered version. A knee prosthesis can also be provided with a patella support on a smooth counter surface from full extension to flexion well past 100 degrees and/or with a mechanism preventing excessive downward tibial component travel.
Abstract:
A total joint arthroplasty (34) is described having a first bearing member (36) (e.g., the femoral head of the femoral component of a total arthroplasty hip joint) and a second bearing member (38) (e.g., an acetabular component) cooperable with the first bearing member (36)with the articulating surfaces of the bearing members (36, 38) in engagement with one another, and wherein at least one of the bearing members (36, 38) has a substrate (50) of a magnesia-stabilized zirconia ceramic material and a bearing surface having a carbon coating (52) applied to the bearing surface.
Abstract:
Apparatus and method for determining the kinematics of a large joint (e.g., a knee) undergoing arthroplasty, for comparing the kinematics of the joint undergoing surgery with the kinematics of the normal joint, and for providing the surgeon with information allowing the balancing of the ligaments of the joint upon the installation of a prosthesis replacement joint. The apparatus (1) includes optical targets (9) mounted on joint replacement components (5, 7) fitted to the resected bones of the joint. One or more video cameras (11) are used to obtain a series of images of the various optical targets as the extremity is flexed, extended, and rotated. A computer (17) is responsive to the images of the targets to determine the kinematics of the joint as it is flexed, extended and rotated. The computer compares the kinematics of the observed joint with the kinematics of a normal joint and determines, based on anomalies of the observed joint relative to the normal joint, whether other implant components or spacers are required, and determines which ligaments must be relaxed or contracted so that the ligaments are balanced. The computer displays suggestions to the surgeon for changing components and for relaxing or contracting specific ligaments such that the ligaments of the joint is balanced with the prosthesis joint in place. A method of computer ligament balancing is also disclosed.
Abstract:
Coated ceramic embraces a fired ceramic body having a surface, with at least part of the surface roughened to accommodate a metal and/or metal alloy coating. On at least part of the roughened surface, the metal/metal alloy coating is applied.
Abstract:
A surgical cable system is provided which includes a surgical cable (1) and a passer (21) for passing the cable (1) around a bone to which the cable (1) is to be secured. The cable (1) includes a main cable (3) having a lead cable (5) attached to one end of the main cable (3) and a fastener (9) preattached to the first end of the main cable (3). The lead cable (5) has an enlargement (7) affixed to its free end. The passer (21) includes a curved probe (25) and a recess or cavity (31) is provided in the probe (25) near its tip (27) and a slot (33) extends from the cavity (31) to the tip (27) of the probe (25). The cavity (31) is sized to accept the enlargement (7) of the lead cable (5) and the slot (33) is sized to receive the lead cable (5) so that as the probe (25) is withdrawn from under the bone, the lead cable (5) and the main cable (3) are pulled under the bone so as to minimize the space required to pass the cable (1).. The lead cable (5) and a portion of the main cable (3) may then be inserted in the fastener (9). The cable (1) is then tensioned to a desired level and the fastener (9) is crimped so as to secure the cable (1) around the bone with the desired level of tension.
Abstract:
A joint replacement component comprising a metal tray (3) and polymer liner (27). The metal tray having screw holes (7a, 7b) for fixation with screws (9) to bone, and a circumferential rim or wall (15) with a smooth inner surface (21). The liner having a flexible sealing ridge (39) around its entire periphery for tray engagement, forming a fluid-tight seal between the liner and tray. The liner having a locking mechanism comprised of tabs (35) at longitudinal ends of the liner, which engage grooves (23) in the tray's front and rear. Following tray fixation to the resected skeletal structure, a surgeon installs the liner within the tray by angling the liner, inserting first tab into its respective groove, pressing the liner downwardly into the tray causing the liners opposing tab to engage its respective groove, snap-locking the liner within the tray, and simultaneously sealing the liner to the tray by the flexible sealing ridge.
Abstract:
Implant with multi-directional pivoting has a first component including a first articular surface and a fore-to-aft and side-to-side rotation device; and a second component including a second articular surface for mating with the first articular surface and a rotation device receptacle. The first component can be mated to the second component through cooperation of the rotation device and the rotation device receptacle, and the first component can cooperate with the second component in contact of the first and second articular surfaces and in articulation of the joint when the first component is mated to the second component. The implant can be an artificial joint which generally has natural load transfer capability. In a particular embodiment, the joint is a knee prosthesis; therein, the first and second components are femoral and tibial components, with the first articular surface a femoral condylar surface and the second articular surface a tibial condylar mating surface. In such a knee, the fore-to-aft component can be considered flexion, with the side-to-side component considered version. As well, a knee prosthesis can be provided with a device to support the patella on a smooth counter surface from full extension to flexion well past 100° and/or with a mechanism to prevent excessive downward travel of the tibial component.
Abstract:
A total joint arthroplasty (34) is described having a first bearing member (36) (e.g., the femoral head of the femoral component of a total arthroplasty hip joint) and a second bearing member (38) (e.g., an acetabular component) cooperable with the first bearing member (36)with the articulating surfaces of the bearing members (36, 38) in engagement with one another, and wherein at least one of the bearing members (36, 38) has a substrate (50) of a magnesia-stabilized zirconia ceramic material and a bearing surface having a carbon coating (52) applied to the bearing surface.
Abstract:
Apparatus and method for determining the kinematics of a large joint (e.g., a knee) undergoing arthroplasty, for comparing the kinematics of the joint undergoing surgery with the kinematics of the normal joint, and for providing the surgeon with information allowing the balancing of the ligaments of the joint upon the installation of a prosthesis replacement joint. The apparatus (1) includes optical targets (9) mounted on joint replacement components (5, 7) fitted to the resected bones of the joint. One or more video cameras (11) are used to obtain a series of images of the various optical targets as the extremity is flexed, extended, and rotated. A computer (17) is responsive to the images of the targets to determine the kinematics of the joint as it is flexed, extended and rotated. The computer compares the kinematics of the observed joint with the kinematics of a normal joint and determines, based on anomalies of the observed joint relative to the normal joint, whether other implant components or spacers are required, and determines which ligaments must be relaxed or contracted so that the ligaments are balanced. The computer displays suggestions to the surgeon for changing components and for relaxing or contracting specific ligaments such that the ligaments of the joint is balanced with the prosthesis joint in place. A method of computer ligament balancing is also disclosed.
Abstract:
An orthopedic component for total joint replacement that comprises a metal tray (3) and polymer liner (27), the metal tray having screw holes (7a, 7b) for fixation with screws (9) to bone and a circumferential rim or wall (15) with a smooth inner surface (21). The liner (27) is provided with a flexible sealing ridge (39) around its entire periphery, the sealing ridge being positioned so that it sealingly engages the tray rim so as to form a fluid-tight seal between the liner and the tray. The liner is provided with a locking mechanism comprised of tabs at the longitudinal ends of the liner which engage grooves in the front and rear of the tray. In this manner, the surgeon can readily install the liner within the tray after the tray has been surgically affixed to the resected skeletal structure by angling the liner and inserting a first tab into its respective groove and then by pressing the liner downwardly into the tray so that another tab at the opposite end of the liner engages its respective groove thus positively locking the liner with respect to the tray. Simultaneously with snap locking the liner within the tray, the flexible sealing ridge on the tray seals the liner with respect to the tray.