Single-condyle prosthesis matched with posterior condyle of femur

Abstract

The invention relates to the field of medical instrument design, in particular to a unicompartmental prosthesis matched with a posterior condyle of a femur, which comprises a joint friction surface, a bone cement binding surface, a distal condyle binding surface and a posterior condyle binding surface of the femur condyle which are integrally formed, the joint friction surface, the bone cement binding surface and the distal condyle binding surface of the femur condyle are three concentric spherical surfaces with different radiuses, the curvature radius RI of the joint friction face is larger than the curvature radius RII of the bone cement binding face, the curvature radius RII of the bone cement binding face is larger than the curvature radius RIII of the femoral condyle far-end binding face, and the femoral condyle posterior condyle binding face is a vertical plane and intersects with the femoral condyle far-end binding face to form an osseointegration face to be matched with a matched bone. According to the product provided by the invention, by changing the design of the bone binding surface of the single-condylar prosthesis, the movable single-condylar prosthesis is more adaptive to the posterior condyle of the femur, and the flexion and extension balance of the knee joint is more accurate, so that postoperative complications are reduced.

Description

technical field [0001] The invention relates to the field of medical device design, in particular to a unicondylar prosthesis adapted to the posterior femoral condyle. Background technique [0002] Unicompartmental knee arthroplasty (unicondylar knee arthroplasty, UKA) is a method for the treatment of unicompartmental knee joint disease. UKA provides more physiological knee kinematics, higher range of motion, and more natural knee joint perception. At present, active unicondylar is widely used in clinical practice, and its clinical results are quite excellent. However, it has been reported in the literature that liner dislocation is one of the main reasons for the failure of active unicompartmental surgery. [0003] The short-term (<5 years), mid-term (5-10 years) and long-term (>10 years) rates of UKA failure caused by dislocation of the active unicompartmental liner were 17%, 8%, and 2%, respectively, and The incidence was higher in Asian populations (kneeling and ...

AI Technical Summary

Problems solved by technology

The main reasons are insufficient liner accommodation: uneven flexion-extension gap; impact of liner; delayed elongation or injury of medial collateral ligament; frequent deep flexion and large medial gap between femoral and tibial components at implantation

With this type of design, it is difficult to achieve precise ligament flexion-extension balance or the ligament flexion-extension balance in the entire range of motion of the knee joint. If the intraoperative flexion-extension balance is inaccurate, it may cause prosthetic loosening, liner dislocation, etc. complication

[0007] There are fewer types of prosthesis. If you choose a smaller femoral prosthesis during the operation, the bone bed will not be fully covered, and the posterior condyle of the femur is prone to impact on the liner during high flexion, resulting in complications such as liner impact dislocation.

Images