Dorr L D, Wan Z
University of Southern California Center for Arthritis and Joint Implant Surgery, Los Angeles 90033, USA.
J Arthroplasty. 1996 Jun;11(4):419-28. doi: 10.1016/s0883-5403(96)80032-5.
One hundred forty-eight primary Anatomic Porous Replacement II (APR-II, Intermedics Orthopaedics, Austin, TX) noncemented total hip arthroplasties were studied at follow-up periods of 2 to 5 years. Because the stem geometry has not changed since 1988, it was possible to study three adjunctive criteria for porous-coated hip arthroplasties. The APR-II stem geometry was used in three groups: APR-II stem in 56 hips, APR-IIS stem with distal sleeve in 44 hips, and APR-IIT stem with circumferential coating and hollow stem in 48 hips. The APR-IIT was followed 2 years; the APR-II and APR-IIS were followed an average of 3.4 years (range, 2-5 years). For comparison of the results within these three groups 2-year results were compared. The results of the APR-II and APR-IIS at the last follow-up examination are also reported. There was no statistical difference within the three groups for any clinical comparison: 82% had excellent results, 14% good, 2% fair, and 2% poor. At the 2-year follow-up examination, radiographic fixation of the APR-IIS was worse than that of the APR-II and APR-IIT (P < .0005). The APR-IIS uses a distal sleeve, which results in an adverse stiffness ratio between bone and stem. Fixation of the APR-IIT was better than that of the APR-II (P < .0005), probably because the APR-IIT had an increased volume and circumferential level of porous coating and was hollowed for stiffness relief. At final follow-up examination, fixation of the APR-IIS was still worse than that of the APR-II (P < .0005). There was no progressive loss of fixation for either the APR-II or APR-IIS between 2 and 5 years. Only 1 of 148 patients was revised for osteolysis. No other stem or acetabular component is loose. The adjunctive use of a modular sleeve seems to have little advantage, whereas stiffness relief of the stem seems to be beneficial. Circumferential porous coating seems the most important factor for durable fixation.
对148例初次使用解剖型多孔置换II型（APR-II，Intermedics Orthopaedics公司，奥斯汀，德克萨斯州）非骨水泥型全髋关节置换术患者进行了2至5年的随访研究。由于自1988年以来柄部几何形状未发生改变，因此有可能对多孔涂层髋关节置换术的三个辅助标准进行研究。APR-II柄部几何形状用于三组：56髋使用APR-II柄，44髋使用带远端套筒的APR-IIS柄，48髋使用带环形涂层和空心柄的APR-IIT柄。对APR-IIT随访2年；对APR-II和APR-IIS平均随访3.4年（范围2至5年）。为比较这三组的结果，对2年的结果进行了比较。还报告了APR-II和APR-IIS在最后一次随访检查时的结果。三组之间的任何临床比较均无统计学差异：82%结果优秀，14%良好，2%一般，2%差。在2年随访检查时，APR-IIS的影像学固定比APR-II和APR-IIT差（P<0.0005）。APR-IIS使用远端套筒，这导致骨与柄之间的刚度比不利。APR-IIT的固定比APR-II好（P<0.0005），可能是因为APR-IIT的多孔涂层体积和环形水平增加，并且为减轻刚度而制成空心。在最后一次随访检查时，APR-IIS的固定仍比APR-II差（P<0.0005）。APR-II或APR-IIS在2至5年之间均未出现固定的进行性丢失。148例患者中仅1例因骨溶解而翻修。没有其他柄或髋臼组件松动。模块化套筒的辅助使用似乎没有什么优势，而柄部的刚度减轻似乎是有益的。环形多孔涂层似乎是持久固定的最重要因素。
