Laskin R S, Bucknell A
Department of Orthopaedic Surgery, Long Island Jewish Medical Center, New Hyde Park, NY 11042.
Clin Orthop Relat Res. 1990 Nov(260):52-5.
Metal backing of polyethylene prosthesis components decreases deformity of the overlying polyethylene and enhances fixation to the underlying bone. Previous metal-backed patellar designs have often failed, primarily because of implant design and implantation technique. In 451 total knee arthroplasties using metal-backed patellar prostheses, there were no implant failures. The implants were dome shaped and did not have a metal endoskeleton. The component was inset into the patellar bone so that the base plate was below the superficial surface of the bone. These factors maximized polyethylene thickness and prevented wearing through to the metal base plate. The advantage of metal backing is that it strengthens the component and allows for possible biologic ingrowth. In this series, the combination of implant design and implantation technique may have eliminated serious problems seen with other metal-backed patellar implants.
聚乙烯假体部件的金属背衬可减少覆盖其上的聚乙烯的变形，并增强与下方骨骼的固定。以往的金属背衬髌骨设计常常失败，主要原因在于植入物设计和植入技术。在451例使用金属背衬髌骨假体的全膝关节置换术中，没有出现植入物失败的情况。这些植入物呈圆顶形状，没有金属内骨骼。该部件嵌入髌骨骨质中，使基板低于骨的表面。这些因素使聚乙烯厚度最大化，并防止磨损至金属基板。金属背衬的优点是它增强了部件强度，并允许可能的生物向内生长。在本系列研究中，植入物设计和植入技术的结合可能消除了其他金属背衬髌骨植入物所出现的严重问题。
