Identifying the incidence of and risk factors for reamputation among patients who underwent foot amputation.

BACKGROUND

Many patients who have lower-extremity amputations secondary to peripheral vascular disease or diabetes require reamputation eventually. This study was designed to identify the incidence of and risk factors for ipsilateral reamputation after forefoot amputation, to evaluate whether postoperative infection increases the risk of reamputation, and to evaluate whether the risk of reamputation was reduced by the duration of antimicrobial therapy after amputation.

METHODS

A retrospective analysis of patients who underwent foot amputation for nontraumatic reason from January 2002 to December 2004 at the Veterans Affairs Pittsburgh Healthcare System was performed.

RESULTS

Among 116 patients, 57 (49.1%) had ipsilateral reamputation within 3 years after their first surgeries; 78.9% received reamputation in the first 6 months; 53 (45.7%) died within 3 years; and 16 (13.8%) developed postoperative infections. Upper level of amputation, long duration of hospitalization, insulin-dependent diabetes, and gangrene on physical examination on admission were risk factors for reamputation in univariate analysis. Gangrene (odds ratio: 3.81, 95% confidence interval: 1.60-9.12, P = 0.003) and insulin-dependent diabetes (odds ratio: 2.93, 95% confidence interval: 1.26-6.78, P = 0.012) were risk factors in multivariate analysis. Postoperative infection did not increase the risk of reamputation. Longer than 2-week course of antibiotic use after amputation did not prevent reamputation.

CONCLUSIONS

Approximately one-half of patients required ipsilateral reamputation and died in 3 years. Gangrene on admission and history of insulin-dependent diabetes were significant risk factors (P = 0.003, P = 0.028). Long duration of antibiotic use after amputation and postoperative infection did not change the risk of reamputation.