Major re-amputation after initial diabetic foot amputation: A retrospective cohort study

Reamputation after initial diabetic foot amputation remains a major clinical challenge associated with substantial morbidity. Identifying factors related to major reamputation may improve patient management and limb preservation. This study evaluated the impact of clinical, metabolic, nutritional, and vascular parameters on the risk of major reamputation. This retrospective cohort study included 141 patients who underwent lower-extremity amputation for diabetic foot disease between 2020 and 2025. Demographic variables, body mass index (BMI), smoking status, peripheral arterial disease (PAD), infection history, glycated hemoglobin (HbA1c) levels, and Prognostic Nutritional Index (PNI) were analyzed. Major reamputation was defined as a subsequent ipsilateral amputation progressing to a below-knee or above-knee level; contralateral amputations and more proximal minor amputations confined to the foot were not considered outcome events. The median follow-up was 3.0 years (range, 1-5). Continuous variables were compared using the Mann-Whitney U test and categorical variables using the Pearson chi-square test. Kaplan-Meier analysis was used to estimate major reamputation-free survival, and Cox proportional hazards regression was performed to evaluate factors associated with time to major reamputation. A Fine-Gray competing-risk analysis was additionally performed considering death before major reamputation as a competing event. Major reamputation occurred in 31 patients (22.0%). Patients with reamputation had significantly lower BMI and PNI values and higher HbA1c levels (all P < .001). Smoking and PAD were significantly more frequent in the reamputation group (both P < .001), whereas no significant between-group differences were observed for age, sex, serum albumin, or infection history. In multivariable Cox regression analysis, PAD (adjusted hazard ratio [HR] 6.25, 95% confidence interval [CI] 2.13-18.32, P < .001) and higher HbA1c (adjusted HR 1.40, 95% CI 1.19-1.65, P < .001) were independently associated with an increased hazard of major reamputation, whereas higher PNI was associated with a reduced hazard (adjusted HR 0.95, 95% CI 0.91-0.99, P = .009). Lower BMI, higher HbA1c, reduced PNI, smoking, and PAD were associated with major reamputation. In multivariable time-to-event analysis, PAD, HbA1c, and PNI remained independently associated with the outcome. These findings demonstrate associations between routinely available clinical parameters and major reamputation and warrant further evaluation in prospective studies.