Implant Research Center, Drexel University, Philadelphia, Pennsylvania.
Orthopaedic Surgery, Rothman Institute, Philadelphia, Pennsylvania.
J Arthroplasty. 2018 Apr;33(4):1235-1241. doi: 10.1016/j.arth.2017.09.036. Epub 2017 Sep 25.
Sequentially annealed, highly crosslinked polyethylene (HXLPE) has been used clinically in total knee arthroplasty (TKA) for over a decade. However, little is known about the revision reasons; its surface damage mechanisms; or its in vivo oxidative stability relative to conventional polyethylene. We asked whether retrieved HLXPE tibial inserts exhibited: (1) similar revision reasons; (2) improved resistance to surface damage; and (3) improved oxidative stability, when compared with conventional gamma inert sterilized polyethylene inserts.
A total of 456 revised tibial inserts were collected in a multicenter retrieval program between 2000 and 2016. The implantation time for the HXLPE components was 1.8 ± 1.8 years, and for the control inserts it was 3.4 ± 2.7 years. Revision reasons were assessed based on medical records, radiographs, and examinations of the retrieved components. Surface damage was assessed using a semi-quantitative scoring method. Oxidation was measured using Fourier transform infrared spectroscopy.
The tibial inserts in both cohorts were revised most frequently for loosening, infection, and instability. The most commonly observed surface damage modes were burnishing, pitting, and scratching. Oxidation of the HXLPE inserts was, on average, low and similar to the control inserts at the bearing surface and the stabilizing post.
We observed evidence of in vivo oxidation in both HXLPE and control tibial inserts. We found no association between the levels of oxidation and the clinical performance of the HXLPE tibial components. The findings of this study document the revision reasons, surface damage modes, and oxidative behavior of sequentially annealed HXLPE for TKA.
连续退火的高交联聚乙烯（HXLPE）已在全膝关节置换术（TKA）中临床应用超过十年。然而，对于其翻修原因、表面损伤机制以及相对于传统聚乙烯的体内氧化稳定性知之甚少。我们想知道回收的 HLXPE 胫骨衬垫是否表现出：（1）相似的翻修原因；（2）改善的表面损伤抗性；以及（3）与传统伽马惰性消毒聚乙烯衬垫相比，改善的氧化稳定性。
在 2000 年至 2016 年的多中心回收计划中，共收集了 456 个修订后的胫骨衬垫。HXLPE 组件的植入时间为 1.8±1.8 年，而对照组件的植入时间为 3.4±2.7 年。根据病历、X 光片和回收组件的检查评估 HXLPE 组件的翻修原因。使用半定量评分法评估表面损伤。使用傅里叶变换红外光谱法测量氧化。
两组的胫骨衬垫最常因松动、感染和不稳定而翻修。最常见的表面损伤模式是抛光、点蚀和划伤。HXLPE 衬垫的氧化程度平均较低，与对照衬垫在承载表面和稳定柱上相似。
我们在 HXLPE 和对照胫骨衬垫中都观察到了体内氧化的证据。我们没有发现氧化水平与 HXLPE 胫骨部件临床性能之间的关联。本研究的结果记录了连续退火 HXLPE 在 TKA 中的翻修原因、表面损伤模式和氧化行为。
