Glyn-Jones Siôn, Thomas Geraint E R, Garfjeld-Roberts Patrick, Gundle Roger, Taylor Adrian, McLardy-Smith Peter, Murray David W
Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, NIHR Musculoskeletal Biomedical Research Unit, Nuffield Orthopaedic Centre, University of Oxford, Windmill Road, Oxford, OX3 7LD, UK.
Clin Orthop Relat Res. 2015 Feb;473(2):432-8. doi: 10.1007/s11999-014-3735-2.
The use of highly crosslinked polyethylene (HXLPE) is now commonplace for total hip arthroplasty. Hip simulator studies and short-term in vivo measurements suggest that the wear rate of some types of HXLPE is significantly less than conventional ultrahigh-molecular-weight polyethylene (UHMWPE). However, there are few long-term data to support its use.
QUESTIONS/PURPOSES: The aim of this study was to measure the long-term steady-state wear of HXLPE compared with UHMWPE liners in a prospective, double-blind, randomized controlled trial using radiostereometric analysis.
Fifty-four patients were randomized to receive hip arthroplasties with either UHMWPE liners or HXLPE liners. Complete followup was available on 39 of these patients (72%). All patients received the same cemented stem and an uncemented acetabular component. Three-dimensional penetration of the head into the socket was determined at 10 years using a radiostereometric analysis system, which has an in vivo accuracy of <0.1 mm. Oxford Hip Scores were compared between the groups.
At 10 years there was significantly less wear of HXLPE (0.003 mm/year; 95% confidence interval [CI], ±0.010; SD 0.023; range, -0.057 to 0.074) compared with UHMWPE (0.030 mm/year; 95% CI, ±0.012; p<0.001; SD 0.0.27; range, -0.001 to 0.164). The volumetric penetration from 1 to 10 years for the UHMWPE group was 98 mm3 (95% CI, ±46 mm3; SD 102 mm3; range, -4 to 430 mm3) compared with 14 mm3 (95% CI, ±40 mm3; SD 91 mm3; range, -189 to 242 mm3) for the HXLPE group (p=0.01).
This study demonstrates that HXLPE has little detectable steady-state in vivo wear. This may result in fewer reoperations from loosening; however, careful clinical followup into the second decade still needs to be performed.
Level I, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
高度交联聚乙烯（HXLPE）如今在全髋关节置换术中的应用已很普遍。髋关节模拟器研究和短期体内测量表明，某些类型的HXLPE磨损率明显低于传统超高分子量聚乙烯（UHMWPE）。然而，几乎没有长期数据支持其使用。
问题/目的：本研究的目的是在一项使用放射立体测量分析的前瞻性、双盲、随机对照试验中，比较HXLPE与UHMWPE衬垫的长期稳态磨损情况。
54例患者被随机分为接受使用UHMWPE衬垫或HXLPE衬垫的髋关节置换术。其中39例患者（72%）获得了完整随访。所有患者均接受相同的骨水泥柄和非骨水泥髋臼部件。使用体内精度<0.1 mm的放射立体测量分析系统在10年时测定股骨头在髋臼中的三维穿透情况。比较两组之间的牛津髋关节评分。
10年时，HXLPE的磨损（0.003 mm/年；95%置信区间[CI]，±0.010；标准差0.023；范围，-0.057至0.074）明显低于UHMWPE（0.030 mm/年；95% CI，±0.012；p<0.001；标准差0.027；范围，-0.001至0.164）。UHMWPE组1至10年的体积穿透为98 mm³（95% CI，±46 mm³；标准差102 mm³；范围，-4至430 mm³），而HXLPE组为14 mm³（95% CI，±40 mm³；标准差91 mm³；范围，-189至242 mm³）（p = 0.01）。
本研究表明HXLPE在体内几乎没有可检测到的稳态磨损。这可能会减少因松动导致的再次手术；然而，仍需要对第二个十年进行仔细的临床随访。
I级，治疗性研究。有关证据水平的完整描述，请参见作者指南。
