Rolling artificial knee joint

Abstract

The present invention belongs to the field of artificial joint. The rolling artificial knee joint includes thigh part, roller, spindle and tibia part. The connection mode includes via the two roller tracks in the thigh part and the two roller tracks in the spindle to form one ring space, setting the roller in the ring space, connecting the libia part and the spindle, setting the spindle in the internal and external condyles and forming two rolling bearing-like structures with the thigh part, roller and spindle. The present invention has reduced prosthesis wear, prolonged use period, low production cost and no biological toxic action of polyethylene and can meet the treatment requirement of patient.

Description

Technical field [0001] The invention relates to an artificial knee joint, particularly a rolling artificial knee joint, which belongs to the field of artificial joints. Background technique [0002] The existing basic structure of artificial knee joints has three kinds of prostheses: restrictive, semi-restrictive and non-restrictive. Their structures are different, but the articular surface between the femur and tibia adopts a sliding friction method. The shortcomings of these artificial knee joints are: (1) In order to reduce the friction coefficient between the femoral and tibial joint surfaces, artificial knee joints mostly use ultra-high molecular weight polyethylene with low friction coefficient and metal as the friction pair. However, UHMWPE has a large amount of wear, which easily leads to long-term failure of the prosthesis. In addition, the severe osteolysis caused by its abrasive particles leads to a high rate of middle and long-term loosening of the prosthesis, which s...

AI Technical Summary

Problems solved by technology

The defects of these artificial knee joints are: (1) in order to reduce the friction coefficient between the femoro-tibial articular surfaces, artificial knee joints mostly adopt ultra-high molecular weight polyethylene and metal with low friction coefficient as the friction pair

However, ultra-high molecular weight polyethylene has a large amount of wear and tear, which can easily lead to long-term failure of the prosthesis

Moreover, the severe osteolysis caused by the abrasive particles will lead to a high loosening rate of the prosthesis in the medium and long term, which will shorten the service life of the artificial joint.

(2) The restrictive prosthesis is limited to a single plane of movement, which can easily cause abnormal concentration of stress at the prosthesis-bone cement-bone tissue interface

The flat polyethylene platform has a small degree of knee joint activity, but because the tibiofemoral joint is in point contact when the knee is flexed, the local compressive stress load is greatly increased, which aggravates the wear of polyethylene and affects its service life

If the articular surface of the polyethylene platform is cup-shaped and the curvature matches the shape of the femoral condyle, increasing the contact of the tibiofemoral articular surface can reduce the compressive stress load per unit area of ​​the joint, but this design also limits joint motion, especially Rotational movement, causing the interface stress of prosthesis-bone cement-bone tissue to increase

After literature search, it was found that H.ThabeBad Kreuznach.Germany wrote an article "Mobile Bearing Total Knee Arthroplasty (Mobile Meniscal Type Total Knee Arthroplasty) in "Proceedings of the Seventh World Artificial Joint Academic Association and International Symposium" p112-115 )”, this paper proposes a design concept of a movable meniscus type artificial knee joint, which is used to solve the contradiction between the matching between the articular surfaces and the range of motion of the joint. However, due to the extremely strict requirements for medical implant materials, it is extremely difficult to improve and obtain approval of materials, and it still cannot avoid the problem of polyethylene wear. In addition, this artificial knee joint also increases A new wear area is the wear between the substrate and the mobile meniscus of polyethylene

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