Division of Orthopaedic Surgery, University of Ottawa, Ottawa, 501 Smyth Road, CCW 1646, Box 502, Ottawa, ON K1H 8L6, Canada.
J Bone Joint Surg Am. 2011 May;93 Suppl 2:118-21. doi: 10.2106/JBJS.J.01848.
Metal-on-metal bearings for hip arthroplasty have been in clinical use for over twenty years with excellent clinical results reported worldwide. A small percentage (<1%) of patients have developed an inflammatory response, and a more severe inflammatory response termed pseudotumor has been more recently reported. The primary purpose of this study was to determine the prevalence of pseudotumor following metal-on-metal hip resurfacing in Canadian academic centers.
Nine of the fourteen centers that perform metal-on-metal hip resurfacings were surveyed. The number of metal-on-metal hip resurfacing arthroplasties performed at each center was determined, as was the number of patients who presented with a pseudotumor and subsequently required revision hip surgery between 2002 and December 2008.
At the nine centers, 3432 hip resurfacing arthroplasties were performed; 76.9% of the patients were male, the mean age was 51.2 years (range, sixteen to eighty-three years), and the mean body-mass index was 28.1 (range, 17 to 55). The mean length of follow-up was 3.4 years (range, two to nine years). A pseudotumor developed after four of the 3432 arthroplasties, for a prevalence of 0.10%.
Although pseudotumors remain a concern after metal-on-metal hip resurfacing, the prevalence at short to midterm follow-up is very low in this multicenter survey. Continued close monitoring is required to determine what clinical factors are involved with the uncommon pseudotumor formation.
金属对金属髋关节置换术在临床上已经使用了二十多年，全世界都报告了出色的临床效果。一小部分(<1%)患者出现了炎症反应，最近还报告了一种更严重的炎症反应，称为假肿瘤。本研究的主要目的是确定加拿大学术中心金属对金属髋关节表面置换术后假肿瘤的患病率。
对 14 个进行金属对金属髋关节表面置换术的中心中的 9 个进行了调查。确定了每个中心进行的金属对金属髋关节表面置换术的数量，以及 2002 年至 2008 年 12 月期间出现假肿瘤并随后需要进行髋关节翻修手术的患者数量。
在这 9 个中心，共进行了 3432 例髋关节表面置换术；76.9%的患者为男性，平均年龄为 51.2 岁（范围 16 至 83 岁），平均体重指数为 28.1（范围 17 至 55）。平均随访时间为 3.4 年（范围 2 至 9 年）。在 3432 例关节置换术后，有 4 例发生了假肿瘤，患病率为 0.10%。
尽管金属对金属髋关节表面置换术后仍存在假肿瘤的担忧，但在这项多中心调查的短期至中期随访中，其患病率非常低。需要继续密切监测，以确定哪些临床因素与罕见的假肿瘤形成有关。
