Department of Orthopaedic Surgery, Haukeland University Hospital, Bergen 5021, Norway.
Clin Orthop Relat Res. 2012 Nov;470(11):3007-13. doi: 10.1007/s11999-012-2396-2.
High prosthesis survival is reported for total hip prostheses with metal and alumina heads, but direct comparisons of a single prosthesis design with one of two different head materials has seldom been studied. Prostheses with zirconia heads are less commonly used than metal and alumina heads, and the few reports suggest variable results with zirconia heads.
QUESTIONS/PURPOSES: We therefore asked: (1) Would metal heads provide better survival of a cemented total hip arthroplasty (THA) than alumina heads? (2) Would metal heads provide better survival of a cemented THA than zirconia heads?
We searched in the Norwegian Arthroplasty Register for cemented primary THA cup/stem combinations that simultaneously had been used with different head materials. The only THA that fulfilled these inclusion criteria was the cemented Reflection All-Poly/Spectron EF (cup/stem) that had during 2001 to 2006 been used both with alumina (n = 448) and cobalt-chromium (n = 5229) heads; that implant had also been used with zirconia (n = 275) and cobalt-chromium heads (n = 3195) during 1997 to 2003, and we included patients with this THA from these two time intervals in the study. All cups were conventional polyethylene. We estimated prosthesis survival and relative revision risks adjusting for age, sex, and diagnosis. The followup in the two study materials was until December 2010.
The survival at 8 years of the Spectron EF/Reflection THAs, inserted with alumina and cobalt-chromium heads during 2001 to 2006, was 92.3% and 94.0%, respectively. The Reflection/Spectron EF THA had inferior survival with zirconia heads compared with cobalt-chromium heads (relative risk, 1.7). At 12 years, the survival rate was 88.1% with cobalt-chromium heads and 74.8% with zirconia heads.
Alumina femoral heads provided no advantage over cobalt-chromium heads on midterm prosthesis survival. THAs with zirconia heads had inferior survival.
Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
全髋关节置换术使用金属和氧化铝头的假体存活率较高，但很少有研究对单一假体设计与两种不同头材料之一进行直接比较。氧化锆头的假体比金属和氧化铝头使用得更少，少数报告表明氧化锆头的结果存在差异。
问题/目的：因此，我们提出了以下问题：（1）金属头是否会比氧化铝头提供更好的骨水泥全髋关节置换术（THA）存活率？（2）金属头是否会比氧化锆头提供更好的骨水泥 THA 存活率？
我们在挪威关节置换登记处搜索了同时使用不同头材料的骨水泥初次 THA 杯/柄组合。只有满足这些纳入标准的是骨水泥反射全聚/光谱 EF（杯/柄），该假体在 2001 年至 2006 年间同时使用了氧化铝（n=448）和钴铬（n=5229）头；该植入物在 1997 年至 2003 年间还使用了氧化锆（n=275）和钴铬头（n=3195），我们将这两个时间段内使用该 THA 的患者纳入研究。所有的杯子都是常规聚乙烯。我们通过调整年龄、性别和诊断来估计假体存活率和相对翻修风险。两种研究材料的随访时间截至 2010 年 12 月。
在 2001 年至 2006 年间插入氧化铝和钴铬头的 Spectron EF/Reflection THA 的 8 年生存率分别为 92.3%和 94.0%。与钴铬头相比，氧化锆头的 Reflection/Spectron EF THA 存活率较低（相对风险，1.7）。在 12 年时，钴铬头的生存率为 88.1%，氧化锆头的生存率为 74.8%。
在中期假体存活率方面，氧化铝股骨头没有优于钴铬头。氧化锆头的 THA 存活率较低。
III 级，治疗研究。有关证据水平的完整描述，请参见作者指南。
