Risk Factors for Major Amputation on Hindfoot Ulcers in Hospitalized Diabetic Patients

Objective: The purpose of this study was to investigate the risk factors for major amputation in patients hospitalized with diabetic foot ulcers involving the hindfoot. Approach: Between January 2003 and October 2017, a total of 1,657 diabetic patients were admitted to the diabetic wound center of Korea University Guro Hospital, for the management of foot ulcers. Among the admitted patients, 117 diabetic patients with hindfoot ulcers were included in this study. One hundred and four patients (89%) healed without major amputation, while 13 patients (11%) healed with major amputation. Data related to 88 potential risk factors, including demographics, ulcer condition, vascularity, bioburden, neurology, and serology, were collected from patients in these two groups for comparison. Results: Among the 88 potential risk factors, 15 showed statistically significant differences between the two groups. In univariate analysis of 88 potential risk factors, nine showed statistically significant differences. In stepwise multiple logistic regression analysis, three of the nine risk factors remained statistically significant. Multivariate-adjusted odds ratios for pulmonary disorders, erythrocyte sedimentation rate (ESR) levels, and total iron-binding capacity (TIBC) levels were 38.525, 1.047, and 0.976, respectively. Innovation: Compared with forefoot and midfoot ulcers, diabetic foot ulcers involving the hindfoot are at increased risk of major amputation because infection may spread proximal to the ankle. However, large-scale cohort studies that specifically discuss the outcomes and characteristics of diabetic hindfoot ulcers are not widely available. Conclusion: Risk factors for major amputation in patients hospitalized with diabetic hindfoot ulcers include pulmonary disorders, high levels of ESR, and decreased TIBC levels.