Department of Orthopaedic Surgery, The University of Arkansas for Medical Sciences, Little Rock, AR.
Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, MO.
J Arthroplasty. 2018 Dec;33(12):3712-3718. doi: 10.1016/j.arth.2018.08.019. Epub 2018 Aug 22.
Total hip arthroplasty (THA) remains a successful procedure for most patients. However, there is a paucity of information regarding the long-term performance of conventional polyethylene (CPE) bearings in young patients undergoing THA.
After accounting for incomplete follow-up of a prospective cohort of 123 THAs in patients ≤50 years, we performed a retrospective review of 101 hips in 84 patients (82.1%) with an average 17.1-year follow-up (14.7-19.6 years). Outcomes of interest included linear and volumetric wear, clinical outcome scores, implant survivorship, and patient mortality. Wear rates were calculated using Martell Software.
Wear analysis revealed median linear and volumetric wear rates of 0.106 mm/y (confidence interval, 0.079-0.133) and 43.58 mm/y (confidence interval, 33.4-53.75). The modified Harris hip scores improved by 36 points while University of California, Los Angeles activity scores improved by 2.0 points at 15-year follow-up (P < .0001). Twenty-two hips (21.8%) were revised, 13 of which (12.8%) were for wear-related causes at an average of 14.9 years (range, 9.2-21 years) from index arthroplasty. There was significantly higher mortality in patients with a preoperative diagnosis of inflammatory avascular necrosis (P = .015).
Because CPE was commonly used in THA over the last 25 years, it is important to understand its implications on the growing revision burden. Significant concerns exist with regard to the long-term durability of CPE bearings in young, moderately active patients 15 years after THA. These patients should be followed closely for wear-related problems. Our results should be used as a comparison when evaluating the outcomes of more modern bearing surface combinations.
全髋关节置换术（THA）仍然是大多数患者的成功手术。然而，对于接受 THA 的年轻患者，常规聚乙烯（CPE）轴承的长期性能信息很少。
在对一个前瞻性队列的 123 例≤50 岁患者的 THA 进行不完全随访后，我们对 84 例患者的 101 髋（82.1%）进行了回顾性研究，平均随访时间为 17.1 年（14.7-19.6 年）。感兴趣的结果包括线性和体积磨损、临床结果评分、植入物存活率和患者死亡率。使用 Martell 软件计算磨损率。
磨损分析显示中位线性和体积磨损率分别为 0.106 毫米/年（置信区间，0.079-0.133）和 43.58 毫米/年（置信区间，33.4-53.75）。在 15 年随访时，改良 Harris 髋关节评分提高了 36 分，加州大学洛杉矶分校活动评分提高了 2.0 分（P<0.0001）。22 髋（21.8%）进行了翻修，其中 13 髋（12.8%）因与磨损相关的原因在指数关节置换术后平均 14.9 年（9.2-21 年）进行了翻修。术前诊断为炎症性缺血性坏死的患者死亡率明显更高（P=0.015）。
由于过去 25 年来 CPE 通常用于 THA，因此了解其对不断增加的翻修负担的影响非常重要。在 THA 后 15 年，对于年轻、活动量适中的患者，CPE 轴承的长期耐用性存在重大问题。这些患者应密切随访磨损相关问题。在评估更现代的轴承表面组合的结果时，应将我们的结果用作比较。
