Hemiarthroplasty Versus Total Hip Arthroplasty for Femoral Neck Fracture in Elderly Patients: Twelve-Month Risk of Revision and Dislocation in an Instrumental Variable Analysis of Medicare Data.

There is practice variation in the selection of a total hip arthroplasty (THA) or a hemiarthroplasty (HA) for the treatment of displaced femoral neck fractures in elderly patients. Large data sets are needed to compare the rates of rare complications following these procedures. We sought to examine the relationship between surgery type and secondary hip surgery (revision or conversion arthroplasty) at 12 months following the index arthroplasty, and that between surgery type and dislocation at 12 months, among elderly Medicare beneficiaries who underwent THA or HA for a femoral neck fracture, taking into account the potential for selection bias. We performed a population-based, retrospective study of elderly (>65 years of age) Medicare beneficiaries who underwent THA or HA following a femoral neck fracture. Two-stage, instrumental variable regression models were applied to nationally representative Medicare medical claims data from 2017 to 2019. Of the 61,695 elderly patients who met the inclusion criteria, of whom 74.1% were female and 92.2% were non-Hispanic White, 10,268 patients (16.6%) underwent THA and 51,427 (83.4%) underwent HA. The findings from the multivariable, instrumental variable analyses indicated that treatment of displaced femoral neck fractures with THA was associated with a significantly higher risk of dislocation at 12 months compared with treatment with HA (2.9% for the THA group versus 1.9% for the HA group; p = 0.001). There was no significant difference in the likelihood of 12-month revision/conversion between THA and HA. The use of THA to treat femoral neck fractures in elderly patients is associated with a significantly higher risk of 12-month dislocation, as compared with the use of HA, although the difference may not be clinically important. A low overall rate of dislocation was found in both groups. The risk of revision/conversion at 12 months did not differ between the groups. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

在老年患者移位性股骨颈骨折的治疗中，全髋关节置换术（THA）和半髋关节置换术（HA）的选择存在实践差异。需要大量数据集来比较这些手术后罕见并发症的发生率。我们试图在因股骨颈骨折接受THA或HA的老年医保受益人中，考虑到选择偏倚的可能性，研究手术类型与初次关节置换术后12个月的二次髋关节手术（翻修或转换关节置换术）之间的关系，以及手术类型与12个月时脱位之间的关系。 我们对股骨颈骨折后接受THA或HA的老年（>65岁）医保受益人进行了一项基于人群的回顾性研究。对2017年至2019年具有全国代表性的医保医疗索赔数据应用了两阶段工具变量回归模型。 在符合纳入标准的61695名老年患者中，74.1%为女性，92.2%为非西班牙裔白人，10268名患者（16.6%）接受了THA，51427名（83.4%）接受了HA。多变量工具变量分析的结果表明，与HA治疗相比，用THA治疗移位性股骨颈骨折在12个月时脱位的风险显著更高（THA组为2.9%，HA组为1.9%；p = 0.001）。THA和HA在12个月翻修/转换的可能性方面没有显著差异。 与使用HA相比，在老年患者中使用THA治疗股骨颈骨折与12个月时脱位的风险显著更高相关，尽管这种差异可能在临床上并不重要。两组的脱位总体发生率都较低。两组在12个月时翻修/转换的风险没有差异。 治疗级别III。有关证据级别完整描述，请参阅作者须知。