McMinn D, Treacy R, Lin K, Pynsent P
Midland International Orthopaedic Service, Birmingham Nuffield Hospital, United Kingdom.
Clin Orthop Relat Res. 1996 Aug(329 Suppl):S89-98. doi: 10.1097/00003086-199608001-00009.
The historical failure of surface replacement has been due to the production of wear debris with subsequent bone resorption, loosening, and failure. To avoid these problems, a surface replacement using a metal on metal bearing allowing thin components and femoral design and instrumentation to avoid varus alignment has been designed. Two hundred thirty-five joints have been resurfaced with this prosthesis in almost 5 years. There have been no femoral neck fractures and no dislocations. There have been 4 designs differing in the method of fixation. In the press fit group, 6 of 70 hips had to be revised for aseptic loosening. In the cemented group, debonding of the cup occurred in 3 of 43 cases. Six patients had hydroxyapatite coated components and have had excellent clinical outcomes. The current design uses a peripherally expanded hydroxyapatite coated cup and a cemented metal head; 116 of this design have been implanted during a 19-month period with excellent outcome. Despite short followup the authors are hopeful that the combination of a polar metal on metal bearing with appropriate fixation will yield a method of preserving bone stock in the younger patient requiring arthroplasty.
以往表面置换失败的原因在于产生磨损碎屑，继而导致骨吸收、松动和失败。为避免这些问题，设计了一种采用金属对金属关节面的表面置换方式，其部件较薄，股骨设计及器械使用可避免内翻对线。在近5年时间里，已有235个关节采用这种假体进行了表面置换。未发生股骨颈骨折和脱位情况。共有4种固定方法不同的设计。在压配组中，70例髋关节中有6例因无菌性松动而需翻修。在骨水泥固定组中，43例中有3例发生髋臼杯脱粘。6例患者使用了羟基磷灰石涂层部件，临床效果极佳。目前的设计采用外周扩展羟基磷灰石涂层髋臼杯和骨水泥固定金属股骨头；在19个月期间已植入116个这种设计的假体，效果良好。尽管随访时间较短，但作者希望极性金属对金属关节面与适当固定方式相结合，能够为需要进行关节置换术的年轻患者提供一种保留骨量的方法。
