Knee disarticulation vs. transfemoral amputation after failed transtibial amputation: Surgical outcome and prosthetic fitting in patients with peripheral vascular disease.

OBJECTIVE: Our aim was to compare transfemoral amputation (TFA) to knee disarticulation (KD) as a reamputation level after failed transtibial amputation (TTA) in patients with peripheral vascular disease and/or diabetes.

METHODS: We studied 152 patients undergoing reamputation, 86 TFA and 66 KD, after a failed TTA. The primary outcome was reamputation and reoperation, and secondary outcomes were prosthetic fitting and mortality. Logistic regression analyses were performed to identify factors associated with the outcome.

RESULTS: The reamputation rate was 36% after KD and 15% after TFA (p = 0.004). The multivariable analysis showed that TFA was associated with a significantly reduced risk of reamputation, odds ratio (OR) = 0.31 (95% confidence interval [95% CI], 0.1-0.7). The overall reoperation rate was 38% after KD and 22% after TFA (p = 0.03). This reduction of risk for TFA was not significant in the multivariable analysis, OR = 0.49 (95% CI, 0.2-1.0). Prosthetic limb fitting was possible in 30% after KD and 19% after TFA (p = 0.1). Previous amputation in the contralateral leg was the only factor associated with reduced ability for prosthetic fitting in the multivariable analysis, OR = 0.15 (95% CI, 0.03-0.7). Mortality at 30 d was 17% and 53% at 1 year. No independent factors affected 30-d mortality in the multivariable analysis.

CONCLUSIONS: In this study, we found a significantly lower risk of reamputation after TFA compared with KD after a failed TTA. We consider TFA to be the reamputation level of choice, especially when there is a need of reducing risk of further reamputations.