Outcomes of minor amputations in patients with peripheral vascular disease over a 10-year period at a tertiary care institution

Abstract

Objectives Choosing an optimal amputation level requires balance between maximizing limb salvage while minimizing chances of non-healing wounds and re-amputation. Our aim was to assess the long-term outcome for minor amputations in patients with peripheral vascular disease. Methods A retrospective study of minor amputations between January 1, 2005 and December 31, 2015 was performed. Electronic medical records of eligible patients were examined to extract demographics, co morbidities and clinical data. Results Within the study period, 220 patients underwent 296 primary minor amputations in 244 lower extremities. Wound healing was achieved in 18.2% (54 of 296 amputations) and 43.6% (129 of 296 amputations) at 90 days and 365 days, respectively. Rates of progression to major amputation were 16.4% (40 or 244 limbs) and 21.7% (53 of 244 limbs) at 90 days and 365 days, respectively. In the final multivariate model, lower ipsilateral posterior tibial waveforms predicted poor 90-day healing (OR = 2.22, p = 0.01) as well as limb loss (OR = 3.02, p = 0.02) in a dose-response manner. In the final logistic regression model, emergency department admission (OR = 0.20, p < 0.01), ipsilateral posterior tibial waveform (OR = 2.63, p < 0.01), and post-operative infection (OR = 0.30, p < 0.01) were predictors of poor healing status at study endpoint. Conclusion This study shows that a majority of foot amputees require ongoing care for non-healing wounds and a proportion necessitate conversion to major amputation. Adequate vascularization is essential to promote and maintain healing.