BACKGROUND AND PURPOSE In the last decade, the direct anterior approach (DAA) for total hip arthroplasty (THA) has become more popular in the Netherlands. Therefore, we investigated the learning curve and survival rate of the DAA in primary THA, using data from the Dutch Arthroplasty Register (LROI). PATIENTS AND METHODS We identified all patients who received a primary THA using the DAA in several high-volume centers in the Netherlands between 2007 and 2019 (n = 15,903). Procedures were ordered per surgeon, using date of operation. Using the procedure number, operations were divided into 6 groups based on the number of previous procedures per surgeon (first 25, 26-50, 51-100, 101-150, 151-200, > 200). Data from different surgeons in different hospitals was pooled together. Revision rates were calculated using a multilevel time-to-event analysis. RESULTS Patients operated on in group 1-25 (hazard ratio [HR] 1.6; 95% CI 1.1-2.4) and 26-50 (HR 1.6; CI 1.1-2.5) had a higher risk for revision compared with patients operated on in group > 200 THAs. Between 50 and 100 procedures the revision risk was increased (HR 1.3; CI 0.9-1.9), albeit not statistically significant. From 100 procedures onwards the HR for revision was respectively 1.0 (CI 0.6-1.6) and 0.8 (CI 0.5-1.4) for patients in operation groups 101-150 and 151-200. Main reasons for revision were loosening of the stem (29%), periprosthetic infection (19%), and dislocation (16%). INTERPRETATION We found a 64% increased risk of revision for patients undergoing THA using the DAA for the first 50 cases per surgeon. Between 50 and 100 cases, this risk was 30% increased, but not statistically significant. From 100 cases onwards, a steady state had been reached in revision rate. The learning curve for DAA therefore is around 100 cases.

中文翻译：

---

直接前路入路的学习曲线为 100 例：基于荷兰关节置换术登记册中 15,875 例全髋关节置换术的分析。

背景和目的在过去十年中，直接前路入路（DAA）进行全髋关节置换术（THA）在荷兰变得越来越流行。因此，我们利用荷兰关节置换术登记处 (LROI) 的数据研究了初次 THA 中 DAA 的学习曲线和存活率。患者和方法 我们确定了 2007 年至 2019 年间在荷兰几个大容量中心使用 DAA 接受初次 THA 的所有患者 (n = 15,903)。手术是由每位外科医生根据手术日期进行的。根据手术次数，根据每位外科医生之前接受的手术次数将手术分为 6 组（前 25 次、26-50 次、51-100 次、101-150 次、151-200 次、> 200 次）。来自不同医院的不同外科医生的数据被汇总在一起。使用多级事件时间分析计算修订率。结果 与组中接受手术的患者相比，第 1-25 组（风险比 [HR] 1.6；95% CI 1.1-2.4）和 26-50（HR 1.6；CI 1.1-2.5）接受手术的患者翻修风险较高> 200 THA。在 50 到 100 次手术之间，翻修风险增加（HR 1.3；CI 0.9-1.9），尽管没有统计学意义。从 100 次手术开始，手术组 101-150 和 151-200 的患者翻修 HR 分别为 1.0 (CI 0.6-1.6) 和 0.8 (CI 0.5-1.4)。翻修的主要原因是假体柄松动（29%）、假体周围感染（19%）和脱位（16%）。解释 我们发现，对于每位外科医生前 50 例使用 DAA 进行 THA 的患者，翻修风险增加了 64%。在 50 到 100 例之间，这种风险增加了 30%，但没有统计学意义。从100例开始，修改率已达到稳定状态。因此，DAA 的学习曲线约为 100 个案例。