Background: 

There is scant evidence to guide decision-making for patients considering total femoral replacement (TFR). We aimed to identify the indication, patient, disease, and surgical technique-related factors associated with failure. We hypothesized that failure occurs more frequently in the setting of revision surgical procedures, with infection as the predominant failure mode.

Methods: 

We performed a retrospective cohort study of patients receiving total femoral endoprostheses for oncological and revision arthroplasty indications; 166 patients met these criteria. Our primary independent variable of interest was TFR for a revision indication (arthroplasty or limb salvage); the primary outcome was failure. Analyses were performed for patient variables (age, sex, diagnosis group, indication), implant variables (model, decade, length, materials), and treatment variables. We analyzed TFR failures with respect to patient factors, operative technique, and time to failure. We conducted bivariate logistic regressions predicting failure and used a multivariate model containing variables showing bivariate associations with failure.

Results: 

Forty-four patients (27%) had treatment failure. Failure occurred in 24 (23%) of 105 primary TFRs and in 20 (33%) of 61 revision TFRs; the difference was not significant (p = 0.134) in bivariate analysis but was significant (p = 0.044) in multivariate analysis. The mean age at the time of TFR was 37 years in the primary group and 51 years in the revision group (p = 0.0006). Of the patients who had mechanical failure, none had reoccurrence of their original failure mode, whereas all 8 patients from the nonmechanical cohort had reoccurrence of the original failure mode; this difference was significant (p = 0.0001).

Conclusions: 

TFR has a high failure rate and a propensity for deep infection, especially in the setting of revision indications and prior infection. All failed TFRs performed for revision indications for infection or local recurrence failed by reoccurrence of the original failure mode and resulted in amputation.

Level of Evidence: 

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

中文翻译：

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非机械性修订指征预示股骨置换后重复肢体救助失败。

背景： 

没有足够的证据指导考虑全股骨置换（TFR）的患者的决策。我们旨在确定与失败相关的适应症，患者，疾病和与手术技术相关的因素。我们假设在修订手术程序中失败发生的频率更高，而感染是主要的失败模式。

方法： 

我们进行了一项回顾性队列研究，研究了接受全股内假体治疗肿瘤和翻修关节置换指征的患者。166名患者符合这些标准。我们感兴趣的主要独立变量是TFR的适应证（人工关节成形术或肢体挽救）；主要结果是失败。对患者变量（年龄，性别，诊断组，适应症），植入物变量（模型，年龄，长度，材料）和治疗变量进行了分析。我们根据患者因素，手术技术和失败时间分析了TFR失败。我们进行了预测故障的双变量逻辑回归，并使用了一个包含变量的多元模型，该变量显示了与故障的双变量关联。

结果： 

四十四名患者（27％）治疗失败。105个主要TFR中有24个（23％）发生故障，而61个修订TFR中有20个（33％）发生故障；在双变量分析中差异不显着（p = 0.134），而在多变量分析中显着（p = 0.044）。小学组TFR发生时的平均年龄为37岁，修订组为51岁（p = 0.0006）。机械性衰竭患者中，无一例恢复其原始衰竭模式，而非机械性队列中的所有8例患者均恢复了原始衰竭模式。这种差异是显着的（p = 0.0001）。

结论： 

TFR的失败率高，容易发生深层感染，尤其是在修订适应症和先前感染的情况下。为恢复感染或局部复发的适应症指示而执行的所有失败的TFR均由于再次出现原始失败模式而失败，并导致截肢。

证据级别： 

治疗级别IV。有关证据水平的完整说明，请参见《作者说明》。