Modular artificial knee system
View Patent ↗A modular knee joint prosthesis is configured to move between an extended position and a flexion position. The modular knee joint prosthesis includes a femoral component that is configured to be mounted to a femur. The femoral component has a first cutout or opening in a central region thereof for receiving a femoral insert. The modular knee joint prosthesis also includes a tibial component that is configured to (i) be mounted either directly or indirectly to a tibia, and (ii) engage the femoral component. The tibial component has a second cutout or opening in a central region thereof for receiving a tibial insert. A kit includes the modular knee joint prosthesis, at least two of the femoral inserts having different geometries, and at least two of the tibial inserts having different geometries.
1 . A modular knee joint prosthesis configured to move between an extended position and a flexion position, the modular knee joint prosthesis comprising:
a femoral component configured to be mounted to a femur, the femoral component having (i) condyles and (ii) a first cutout or opening located between the condyles,
a femoral insert removably mounted within the first cutout or opening of the femoral component by a first sliding rail and slot engagement, the first sliding rail and slot engagement including either elongated rails or elongated slots disposed on opposing sides of the femoral insert and extending in an anterior-posterior direction when the modular knee joint prosthesis is maintained in the extended position,
a tibial component configured to (i) be mounted either directly or indirectly to a tibia, and (ii) engage the femoral component,
the tibial component having (i) bearing surfaces for directly engaging the condyles of the femoral component, and (ii) a second cutout or opening located between the bearing surfaces,
a tibial insert removably mounted within the second cutout or opening of the tibial component by a second sliding rail and slot engagement, the second sliding rail and slot engagement including either elongated rails or elongated slots disposed on opposing sides of the tibial insert and extending in the anterior-posterior direction when the modular knee joint prosthesis is maintained in the extended position, and
a femoral gear disposed on the femoral insert and a tibial gear disposed on the tibial insert, wherein the femoral and tibial gears are configured to be meshed together.
2 . The modular knee joint prosthesis of claim 1 , wherein the femoral and tibial gears are configured to be meshed together in both the extended and flexion positions.
3 . The modular knee joint prosthesis of claim 1 , wherein the femoral and tibial gears have gear teeth.
4 . The modular knee joint prosthesis of claim 1 , wherein the tibial component comprises an articular insert, and the second cutout or opening is formed in the articular insert, and wherein the articular insert is configured to be sandwiched between the femoral component and a tibial baseplate that is mounted directly to the tibia.
5 . A kit comprising the modular knee joint prosthesis of claim 1 and further comprising at least two of the femoral inserts having different geometries, and at least two of the tibial inserts having different geometries.
6 . A modular knee joint prosthesis configured to move between an extended position and a flexion position, the modular knee joint prosthesis comprising:
a femoral component configured to be mounted to a femur, the femoral component having (i) condyles and (ii) a first cutout or opening located between the condyles,
a femoral insert mounted within the first cutout or opening of the femoral component, the femoral insert having a femoral gear,
a tibial component configured to (i) be mounted either directly or indirectly to a tibia, and (ii) engage the femoral component, the tibial component having (i) bearing surfaces for directly engaging the condyles of the femoral component, and (ii) a second cutout or opening located between the bearing surfaces,
a tibial insert mounted within the second cutout or opening of the tibial component, the tibial insert having a tibial gear, wherein the femoral and tibial gears are configured to be meshed together,
wherein at least one of the gears follows a helical trajectory to cause movement of the tibial component in either a medial or lateral direction as the knee joint prosthesis is moved to the extended position.
7 . A modular knee joint prosthesis configured to move between an extended position and a flexion position, the modular knee joint prosthesis comprising:
a femoral component configured to be mounted to a femur, the femoral component having (i) condyles and (ii) a first cutout or opening located between the condyles, and
a femoral insert mounted within the first cutout or opening of the femoral component, the femoral insert having a blade protruding therefrom,
a tibial component configured to (i) be mounted either directly or indirectly to a tibia, and (ii) engage the femoral component, the tibial component having (i) bearing surfaces for directly engaging the condyles of the femoral component, and (ii) a second cutout or opening located between the bearing surfaces, and
a tibial insert mounted within the second cutout or opening of the tibial component, the tibial insert having a slot disposed therein, wherein the blade is configured to be positioned within the slot in both the extended and flexion positions,
wherein the blade follows a helical trajectory to cause movement of the tibial component in either a medial or lateral direction as the knee joint prosthesis is moved to the extended position.
8 . A modular knee joint prosthesis configured to move between an extended position and a flexion position, the modular knee joint prosthesis comprising:
a femoral component configured to be mounted to a femur, the femoral component having (i) condyles and (ii) a first cutout or opening located between the condyles,
a femoral insert removably mounted within the first cutout or opening of the femoral component by a first sliding rail and slot engagement, the first sliding rail and slot engagement including either elongated rails or elongated slots disposed on opposing sides of the femoral insert and extending in an anterior-posterior direction when the modular knee joint prosthesis is maintained in the extended position,
a tibial component configured to (i) be mounted either directly or indirectly to a tibia, and (ii) engage the femoral component,
the tibial component having (i) bearing surfaces for directly engaging the condyles of the femoral component, and (ii) a second cutout or opening located between the bearing surfaces,
a tibial insert removably mounted within the second cutout or opening of the tibial component by a second sliding rail and slot engagement, the second sliding rail and slot engagement including either elongated rails or elongated slots disposed on opposing sides of the tibial insert and extending in the anterior-posterior direction when the modular knee joint prosthesis is maintained in the extended position, and
a post protruding from the tibial insert and an opening disposed on the femoral insert, wherein the post is configured to be positioned within the opening in both the extended and flexion positions, wherein the post protrudes from a concave surface formed on the tibial insert, and the opening is disposed on a convex surface formed on the femoral insert, wherein the concave surface is configured to be positioned against the convex surface in both the extended and flexion positions.