Santavirta S, Takagi M, Gómez-Barrena E, Nevalainen J, Lassus J, Salo J, Konttinen Y T
Department of Orthopaedics and Traumatology, Helsinki University Central Hospital, Finland.
J Long Term Eff Med Implants. 1999;9(1-2):67-76.
The use of implanted biomaterials in orthopedic surgery has increased rapidly during the past two decades. Total joint replacement of the hip or knee joint has become common treatment; at the same time, an increasing number of fractures are treated with osteosynthesis. The original Charnley low-friction arthroplasty of the hip is still widely used and gives in large series excellent results. Aseptic loosening of this arthroplasty has been thought to be due to wear debris of the methylmethacrylate used for fixation of the implants, or to debris generated from wear of the polyethylene socket. To date, many different materials have been tried in order to reduce wear and generation of macrophage irritating submicron sized particles, or to provide more biocompatible components. However, trials to improve the methylmethacrylate cement or to invent better polyethylenes have often failed. Diamond coating of the metallic components seems promising: there is less wear and diamond is very biocompatible in bulk and small particulate form. Biodegradable implants have also been found useful in treating fractures. Bioactive bioabsorbable materials may also make possible a tissue engineering approach and can be used as carriers for selected drugs and cytokines. Because many promising materials and designs have failed in clinical use, extensive theoretical and experimental testing is mandatory before introducing new materials and implants in a clinical setting.
在过去二十年中，骨科手术中植入生物材料的使用迅速增加。髋关节或膝关节的全关节置换已成为常见的治疗方法；与此同时，越来越多的骨折采用骨固定术治疗。最初的Charnley髋关节低摩擦置换术仍被广泛使用，并且在大量病例中都取得了优异的效果。这种置换术的无菌性松动被认为是由于用于固定植入物的甲基丙烯酸甲酯的磨损碎片，或者是聚乙烯髋臼杯磨损产生的碎片所致。迄今为止，人们已经尝试了许多不同的材料，以减少磨损和巨噬细胞刺激性亚微米级颗粒的产生，或者提供更具生物相容性的部件。然而，改进甲基丙烯酸甲酯骨水泥或发明更好的聚乙烯的尝试往往失败了。金属部件的金刚石涂层似乎很有前景：磨损较少，而且金刚石在块状和小颗粒形式下都具有很好的生物相容性。可生物降解的植入物在治疗骨折方面也已被证明是有用的。生物活性可生物吸收材料也可能使组织工程方法成为可能，并可作为选定药物和细胞因子的载体。由于许多有前景的材料和设计在临床应用中失败了，因此在临床环境中引入新材料和植入物之前，必须进行广泛的理论和实验测试。
