de Steiger Richard Noel, Lorimer Michelle, Solomon Michael
Department of Surgery, Epworth Healthcare, University of Melbourne, AOA National Joint Replacement Registry, Hoddle Street, Richmond, VIC, 3121, Australia.
Data Management and Analysis Centre, Discipline of Public Health, University of Adelaide, Adelaide, Australia.
Clin Orthop Relat Res. 2015 Dec;473(12):3860-6. doi: 10.1007/s11999-015-4565-6.
There are many factors that may affect the learning curve for total hip arthroplasty (THA) and surgical approach is one of these. There has been renewed interest in the direct anterior approach for THA with variable outcomes reported, but few studies have documented a surgeon's individual learning curve when using this approach.
QUESTIONS/PURPOSES: (1) What was the revision rate for all surgeons adopting the anterior approach for placement of a particular implant? (2) What was the revision rate for surgeons who performed > 100 cases in this fashion? (3) Is there a minimum number of cases required to complete a learning curve for this procedure?
The Australian Orthopaedic Association National Joint Replacement Registry prospectively collects data on all primary and revision joint arthroplasty surgery. We analyzed all conventional THAs performed up to December 31, 2013, with a primary diagnosis of osteoarthritis using a specific implant combination and secondarily those associated with surgeons performing more than 100 procedures. Ninety-five percent of these procedures were performed through the direct anterior approach. Procedures using this combination were ordered from earliest (first procedure date) to latest (last procedure date) for each individual surgeon. Using the order number for each surgeon, five operation groups were defined: one to 15 operations, 16 to 30 operations, 31 to 50 operations, 51 to 100 operations, and > 100 operations. The primary outcome measure was time to first revision using Kaplan-Meier estimates of survivorship.
Sixty-eight surgeons performed 5499 THAs using the specified implant combination. The cumulative percent revision at 4 years for all 68 surgeons was 3% (95% confidence interval [CI], 2.5-3.8). For surgeons who had performed over 100 operations, the cumulative revision rate was 3% (95% CI, 2.0-3.5). It was not until surgeons had performed over 50 operations that there was no difference in the cumulative percent revision compared with over 100 operations. The cumulative percent revision for surgeons performing 51 to 100 operations at 4 years was 3% (95% CI, 1.5-5.4) and over 100 operations 2% (95% CI, 1.2-2.7; hazard ratio, 1.40 [95% CI, 0.7-2.7]; p = 0.33).
There is a learning curve for the anterior approach for THA even when using a prosthesis combination specifically marketed for that approach. We found that 50 or more procedures need to be performed by a surgeon before the rate of revision is no different from performing 100 or more procedures. Surgeons should be aware of this initial higher rate of revision when deciding which approach delivers the best outcome for their patients.
有许多因素可能影响全髋关节置换术（THA）的学习曲线，手术入路就是其中之一。人们对THA的直接前路入路重新产生了兴趣，报道的结果各不相同，但很少有研究记录外科医生使用这种入路时的个人学习曲线。
问题/目的：（1）所有采用前路入路植入特定假体的外科医生的翻修率是多少？（2）以这种方式完成超过100例手术的外科医生的翻修率是多少？（3）完成该手术的学习曲线所需的最少病例数是多少？
澳大利亚骨科协会国家关节置换登记处前瞻性收集所有初次和翻修关节置换手术的数据。我们分析了截至2013年12月31日进行的所有传统THA，其主要诊断为骨关节炎，使用特定的假体组合，其次分析了与进行超过100例手术的外科医生相关的病例。这些手术中有95%是通过直接前路入路进行的。对于每位外科医生，使用这种组合的手术按最早（第一个手术日期）到最晚（最后一个手术日期）排序。根据每位外科医生的序号，定义了五个手术组：1至15例手术、16至30例手术、31至50例手术、51至100例手术以及超过100例手术。主要结局指标是使用Kaplan-Meier生存估计法计算的首次翻修时间。
68位外科医生使用指定假体组合进行了5499例THA。所有68位外科医生在4年时的累积翻修率为3%（95%置信区间[CI]为2.5 - 3.8）。对于进行了超过100例手术的外科医生，累积翻修率为3%（95%CI为2.0 - 3.5）。直到外科医生进行了超过50例手术后，累积翻修率与超过100例手术时才没有差异。在4年时，进行51至100例手术外科医生的累积翻修率为3%（95%CI为1.5 - 5.4），超过100例手术的为2%（95%CI为1.2 - 2.7；风险比为1.40[95%CI为0.7 - 2.7]；p = 0.33）。
即使使用专门为此入路销售的假体组合，THA的前路入路也存在学习曲线。我们发现，外科医生需要进行50例或更多手术，之后翻修率才与进行100例或更多手术时没有差异。在决定哪种入路能为患者带来最佳结果时，外科医生应意识到这种初始较高的翻修率。
