Reliability and validation of three scoring systems in the assessment of diabetic foot ulcers

Abstract

Introduction Diabetic foot ulcers represent a major cause of morbidity and are frequently associated with infection, delayed healing, and limb loss. Accurate risk stratification using standardized scoring systems is essential for predicting outcomes and guiding management decisions. The present study aimed to evaluate and compare three ulcer scoring systems (Diabetic Ulcer Severity Score (DUSS), Site, Ischemia, Neuropathy, Bacterial Infection, Area, and Depth (SINBAD) scoring, and University of Texas classification) in predicting clinical outcomes, specifically secondary healing, requirement of split-thickness skin grafting (STSG), and lower limb amputation, among patients with diabetic foot ulcers. Materials and methods This prospective observational study included 107 patients aged ≥35 years with diabetic foot ulcers treated at a tertiary care centre over two years. Ulcers were assessed at baseline using the Diabetic Ulcer Severity Score, the University of Texas (UT) classification, and the SINBAD scoring system. Patients were followed until a definitive outcome. Clinical outcomes were categorized as secondary healing, requirement of split thickness skin grafting, or lower limb amputation. Non-parametric statistical analysis was performed using the Kruskal-Wallis test, and a p-value <0.05 was considered statistically significant. Results The mean age of participants was 56.84 ± 12.32 years, with a male predominance (84, 78.3%). Most ulcers were located in the midfoot (45, 42.1%) and forefoot (44, 41.1%). STSG was required in 84 (78.5%) patients, amputation was performed in 18 (16.8%), and secondary healing occurred in five (4.7%). DUSS and UT classification did not show statistically significant differences across outcome groups. In contrast, SINBAD scores were significantly higher in the amputation group (median 5, IQR 4-6) compared to the STSG group (median 4, IQR 3-5) and secondary healing group (median 2, IQR 1-2) (H=8.02, p=0.018), demonstrating better discriminatory ability. Conclusion Among the evaluated scoring systems, SINBAD showed superior predictive performance for adverse clinical outcomes and may serve as a practical tool for risk stratification in diabetic foot ulcer management.