Wakefield Orthopaedic Clinic, 270 Wakefield Street, Adelaide, SA, 5000, Australia.
Clin Orthop Relat Res. 2010 Oct;468(10):2704-9. doi: 10.1007/s11999-010-1259-y. Epub 2010 Feb 12.
First-generation highly cross-linked polyethylene liners have reduced the incidence of wear particle-induced osteolysis. However, failed acetabular liners have shown evidence of surface cracking, mechanical failure, and oxidative damage. This has led to the development of second-generation highly cross-linked polyethylene, which has improved wear and mechanical properties and resistance to oxidation in vitro. Owing to its recent introduction, there are no publications describing its clinical performance.
QUESTIONS/PURPOSES: We assessed early clinical wear of a second-generation highly cross-linked polyethylene liner and compared its clinical performance with the published results of hip simulator tests and with first-generation highly cross-linked polyethylene annealed liners.
Twenty-one patients were enrolled in a prospective cohort study. Clinical outcome and femoral head penetration were measured for 19 patients at 6 months and 1 and 2 years postoperatively.
The median proximal head penetration was 0.009 mm and 0.024 mm at 1 and 2 years, respectively. The median two-dimensional (2-D) head penetration was 0.083 mm and 0.060 mm at 1 and 2 years, respectively. The median proximal wear rate between 1 and 2 years was 0.015 mm/year.
The wear rate calculated was similar to the in vitro wear rate reported for this material; however, it was less than the detection threshold for this technique. Although longer followup is required for wear to reach a clinically quantifiable level, this low level of wear is encouraging for the future clinical performance of this material.
Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
第一代高度交联聚乙烯衬垫降低了磨损颗粒诱导性骨溶解的发生率。然而，失败的髋臼衬垫已显示出表面裂纹、机械故障和氧化损伤的证据。这导致了第二代高度交联聚乙烯的发展，它在体外提高了耐磨性和机械性能以及抗氧化能力。由于它是最近引入的，因此没有描述其临床性能的出版物。
问题/目的：我们评估了第二代高度交联聚乙烯衬垫的早期临床磨损，并将其临床性能与髋关节模拟器试验的已发表结果以及第一代高度交联聚乙烯退火衬垫进行了比较。
21 名患者被纳入前瞻性队列研究。19 名患者在术后 6 个月、1 年和 2 年时测量临床结果和股骨头穿透。
中位数近端头部穿透分别为 0.009 毫米和 0.024 毫米，分别为 1 年和 2 年。中位数二维（2-D）头部穿透分别为 0.083 毫米和 0.060 毫米，分别为 1 年和 2 年。1 年至 2 年间的中位数近端磨损率为 0.015 毫米/年。
计算的磨损率与该材料的体外磨损率相似，但低于该技术的检测阈值。尽管需要更长的随访时间才能使磨损达到可临床量化的水平，但这种低水平的磨损对该材料的未来临床性能是令人鼓舞的。
IV 级，治疗研究。请参阅作者指南，以获得完整的证据水平描述。
