BACKGROUND AND PURPOSE Unicompartmental knee arthroplasty (UKA) has increased in use. We investigated changes to UKA revision risk over the last 20 years compared with total knee arthroplasty (TKA), examined external and patient factors for correlation to UKA revision risk, and described the survival probability for current UKA and TKA practice. PATIENTS AND METHODS All knee arthroplasties reported to the Danish Knee Arthroplasty Register from 1997 to 2017 were linked to the National Patient Register and the Civil Registration System for comorbidity, emigration, and mortality information. All primary UKA and TKA patients with primary osteoarthritis were included and propensity score matched 4 TKAs to 1 UKA. Revision and mortality were analyzed using competing risk cox regression with a shared gamma frailty component. RESULTS The matched cohort included 48,195 primary knee arthroplasties (9,639 UKAs). From 1997-2001 to 2012-2017 the 3-year hazard ratio decreased from 5.5 (95% CI 2.7-11) to 1.5 (CI 1.2-1.8) due to increased UKA survival. Cementless fixation, a high percentage usage of UKA, and increased surgical volume decreased UKA revision risk, and increased in occurrence parallel to the decreasing revision risks. Current UKA practice using cementless fixation at a high usage unit has a 3-year implant survival of 96% (CI 97-95), 1.1% lower than current TKA practice. INTERPRETATION UKA revision risk has decreased over the last 20 years, nearing that of TKA surgery. High usage rates, surgical volume, and the use of cementless fixation have increased during the study and were associated with decreased UKA revision risks.

中文翻译：

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优化的内侧单间室膝关节置换术结果：从 20 年倾向评分匹配的注册数据中学习。


背景和目的单间室膝关节置换术（UKA）的使用有所增加。我们调查了过去 20 年来 UKA 翻修风险与全膝关节置换术 (TKA) 相比的变化，检查了外部因素和患者因素与 UKA 翻修风险的相关性，并描述了当前 UKA 和 TKA 实践的生存概率。患者和方法 1997 年至 2017 年向丹麦膝关节置换登记册报告的所有膝关节置换术均与国家患者登记册和民事登记系统相关联，以获取合并症、移民和死亡率信息。所有患有原发性骨关节炎的原发性 UKA 和 TKA 患者均纳入其中，倾向评分将 4 个 TKA 与 1 个 UKA 相匹配。使用竞争风险 cox 回归和共享的伽马衰弱成分来分析翻修和死亡率。结果 匹配队列包括 48,195 例初次膝关节置换术（9,639 例 UKAs）。从 1997-2001 年到 2012-2017 年，由于 UKA 生存率增加，3 年风险比从 5.5 (95% CI 2.7-11) 降至 1.5 (CI 1.2-1.8)。无骨水泥固定、UKA 的高比例使用以及手术量的增加降低了 UKA 翻修风险，并且与翻修风险降低的同时发生率也增加。目前 UKA 实践在高使用率单位使用无骨水泥固定，3 年种植体存活率为 96% (CI 97-95)，比当前 TKA 实践低 1.1%。解释 UKA 翻修风险在过去 20 年中有所下降，接近 TKA 手术。研究期间高使用率、手术量和无骨水泥固定的使用有所增加，并且与 UKA 翻修风险降低相关。