Validation of an algorithm to predict reulceration in amputation patients with diabetes

Abstract

The aim of this article was to assess the ability to predict reulceration in people with diabetes and a history of minor amputation according to the formula proposed by Miller et al. A retrospective study was performed on 156 consecutive records of patients with a recent history of simple or multiple forefoot amputation. The sample was divided according to Miller's formula into patients at low risk of reulceration and those at high risk; those were further divided into two subgroups according to whether or not the first segment of the forefoot had been amputated. Forty-eight (47·1%) individuals suffered forefoot reulceration, showing a median reulceration-free survival time of 8 months [interquartile range (IR) 3·6-14·8]. Nephropathy (P = 0.005) and Miller's formula (P = 0.028) were risk factors for reulceration-free survival time in the univariate analysis. The pattern relating to the first segment amputated [hazard ratio (HR) 2·853; P = 0·004; 95% confidence interval (CI) 1·391-5·849] and nephropathy (HR 2·468; P = 0.004; 95% CI 1.328-4.587) showed a significant hazard ratio in the multivariate Cox model. Participants with first segment amputation and one other amputation showed an association with the probability of reulceration in comparison with any other specific type of minor amputation.