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

Abstract

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. 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. 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. 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.