Milosev Ingrid, Trebse Rihard, Kovac Simon, Cör Andrej, Pisot Venceslav
Orthopaedic Hospital Valdoltra, Jadranska c. 31, 6280 Ankaran, Slovenia.
J Bone Joint Surg Am. 2006 Jun;88(6):1173-82. doi: 10.2106/JBJS.E.00604.
Second-generation metal-on-metal total hip replacements were introduced in the early 1990s with the aim of eliminating polyethylene wear and the resulting complications of osteolysis and aseptic loosening. The goal of the present study was to evaluate the intermediate-term results in a series of patients who were managed with one of these implants.
Between 1994 and 2002, we performed 640 total hip replacements in 591 patients with use of a Bicon-Plus cementless threaded cup with a polyethylene liner housing a metal inlay made of Sikomet low-carbon cobalt-chromium-molybdenum alloy that articulates with a Sikomet metal femoral head. Clinical and radiographic evaluation was performed retrospectively at a mean of 7.1 years postoperatively. Histologic analysis was performed on specimens retrieved from seventeen hips that were revised, and wear measurements were made for six hips that were revised.
Thirty-four hips (thirty-four patients) were revised because of infection (six hips), aseptic loosening (twenty-three hips), pain without loosening (two hips), or other reasons (three hips). The survival rate of the prosthesis as a whole at ten years, with revision for any reason as the end point, was 0.91 (95% confidence interval, 0.88 to 0.95). The survival rate of the cup was 0.94 (95% confidence interval, 0.90 to 0.97), and that of the stem was 0.96 (95% confidence interval, 0.94 to 0.98). Linear or expansile osteolysis, or both, was observed on the radiographs of sixteen (64%) of the twenty-five hips that were revised because of aseptic loosening and/or pain. Histological analysis of pericapsular tissue was performed for seventeen of the twenty-five hips that were revised because of aseptic loosening and/or pain. Thirteen of these seventeen hips demonstrated a hypersensitivity-like reaction with aseptic inflammatory changes accompanied by moderate to extensive diffuse and perivascular infiltration of lymphocytes. In the six retrieved specimens that were subjected to wear analysis, the main wear mode was abrasive wear. The mean cumulative linear wear for the bearing was 31.3 microm, and the mean annual wear rate was 6.3 microm/yr. The mean clearance was 87.6 microm.
After a mean duration of follow-up of seven years, aseptic loosening was the major reason for failure of Sikomet metal-on-metal prostheses. The histological findings and the prevalence of osteolysis suggest the possibility of a hypersensitivity-like immunological response to wear particles.
第二代金属对金属全髋关节置换术于20世纪90年代初开始应用，旨在消除聚乙烯磨损以及由此产生的骨溶解和无菌性松动并发症。本研究的目的是评估使用其中一种植入物治疗的一系列患者的中期结果。
1994年至2002年期间，我们对591例患者实施了640例全髋关节置换术，使用的是带有聚乙烯内衬的Bicon-Plus无水泥螺纹杯，内衬中容纳由Sikomet低碳钴铬钼合金制成的金属嵌体，该嵌体与Sikomet金属股骨头相铰接。术后平均7.1年进行回顾性临床和影像学评估。对17例翻修髋关节取出的标本进行组织学分析，对6例翻修髋关节进行磨损测量。
34例髋关节（34例患者）因感染（6例髋关节）、无菌性松动（23例髋关节）、无松动疼痛（2例髋关节）或其他原因（3例髋关节）而进行翻修。以任何原因翻修为终点，假体10年的总体生存率为0.91（95%置信区间，0.88至0.95）。髋臼杯的生存率为0.94（95%置信区间，0.90至0.97），股骨柄的生存率为0.96（95%置信区间，0.94至0.98）。在因无菌性松动和/或疼痛而翻修的25例髋关节中，16例（64%）的X线片上观察到线性或膨胀性骨溶解，或两者皆有。对因无菌性松动和/或疼痛而翻修的25例髋关节中的17例进行了关节周围组织的组织学分析。这17例髋关节中有13例表现出类似超敏反应，伴有无菌性炎症改变，伴有中度至广泛的淋巴细胞弥漫性和血管周围浸润。在6例进行磨损分析的取出标本中，主要磨损模式为磨粒磨损。关节面的平均累积线性磨损为31.3微米，平均年磨损率为6.3微米/年。平均间隙为87.6微米。
平均随访7年后，无菌性松动是Sikomet金属对金属假体失败的主要原因。组织学发现和骨溶解的发生率提示对磨损颗粒可能存在类似超敏反应的免疫反应。
