BACKGROUND AND PURPOSE The risk of dislocation after primary total hip arthroplasty (THA) is affected by several factors, which increases the possibility of substantial differences among hospitals. We compared cumulative incidences of dislocation between regions and hospitals after primary THA surgery in osteoarthritis (OA) patients. PATIENTS AND METHODS From the Danish Hip Arthroplasty Register, we included 31,105 THAs performed from 2010 to 2014 with 2 years' follow-up. Dislocations treated by closed reduction were identified in the Danish National Patient Register combined with patient file review. The results are presented as 2-year cumulative incidence on national, regional, and hospital level as proportions with 95% confidence intervals (CI) and as adjusted odds ratios (OR) analyzed by multiple logistic regression. RESULTS 1,861 dislocations in 1,079 THAs were identified from 59 orthopedic departments. The 2-year cumulative incidence ranged from 2.2% to 4.3% between the 5 regions in Denmark. Hospital variation was 0-12%. For hospitals with a 5-year volume of more than 100 procedures, the incidence was 0.9-7.4%. Using the highest volume hospital as the reference, ORs for dislocation for the remaining hospitals were between 0.3 (CI 0.1-0.6) and 2.7 (1.9-4.0) after adjusting for age, sex, head size, and fixation method. Low-volume hospitals showed a higher dislocation risk than high-volume units with an adjusted OR of 1.2 (1.1-1.4). INTERPRETATION We found substantial variation in the incidence of dislocation between hospitals within Denmark, which can be explained by a combination of patient-, component-, and surgery-related factors. There is a need for continuous monitoring of THA dislocation on regional and hospital levels to reduce overall and local dislocation risk for future patients.

中文翻译：

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原发性骨关节炎初次全髋关节置换术后脱位风险的医院差异很大：来自丹麦髋关节置换登记册的 59 家医院的 31,105 名患者。

背景和目的 初次全髋关节置换术 (THA) 后脱位的风险受多种因素的影响，这增加了医院之间存在实质性差异的可能性。我们比较了骨关节炎 (OA) 患者初次 THA 手术后不同地区和医院的累计脱位发生率。患者和方法 我们从丹麦髋关节置换登记册中纳入了 2010 年至 2014 年进行的 31,105 例全髋关节置换术，并进行了 2 年的随访。通过闭合复位治疗的脱臼在丹麦国家患者登记处结合患者档案审查进行了鉴定。结果显示为国家、地区和医院水平的 2 年累积发病率与 95% 置信区间 (CI) 的比例和通过多元逻辑回归分析的调整比值比 (OR)。结果 1, 从 59 个骨科部门确定了 1,079 个 THA 中的 861 个脱臼。丹麦 5 个地区的 2 年累积发病率在 2.2% 到 4.3% 之间。医院差异为 0-12%。对于 5 年手术量超过 100 例的医院，发生率为 0.9-7.4%。以容量最大的医院为参考，在调整年龄、性别、头部大小和固定方法后，其余医院脱位的 OR 介于 0.3 (CI 0.1-0.6) 和 2.7 (1.9-4.0) 之间。低容量医院显示出比高容量单位更高的错位风险，调整后的 OR 为 1.2 (1.1-1.4)。解释 我们发现丹麦各医院之间的脱臼发生率存在显着差异，这可以通过患者、组件和手术相关因素的组合来解释。