SCREW ANCHORED JOINT PROSTHESIS

摘要

Screw-based primary fixation (5) of the prosthetic components within the medullary cavity solves the problem of micro-movements encountered in conventional press fit cementless fixation. For a total hip prosthesis (10), the stem (1) is fixed to the medial cortex of the proximal femur by the medial approach alone, obviating the need for drilling of the lateral cortex. The stem (1) may be implanted using a special drill guide instrumentation. Anchoring screws (5) are locked into the stem (1) of the femoral component (10), while self cutting threads on the screw heads (17) engage the pre-drilled medial cortex. This novel fixation principle can also be applied to other joint prosthesis, e.g. finger, shoulder, elbow and knee, as well as to dental and spinal implants.