Heel Diabetic Foot Osteomyelitis: A Current Challenge in the Clinical Practice

The current study aimed to evaluate the outcomes of heel diabetic foot osteomyelitis (DFO) managed in a specialized diabetic foot service. The research is a single-center retrospective observational study including a population of patients with diabetic foot ulcers (DFUs) complicated by DFO and requiring hospitalization, managed between 2019 and 2022 in a tertiary level diabetic foot service. According to the location of bone infection, patients were divided into two groups: those with heel DFO and those with forefoot/midfoot DFO. After one year of follow-up, the following outcomes were evaluated and compared between groups: healing, healing time, major amputation, and mortality. Overall, 114 patients were included. The mean age was 67.9 ± 12, most of them were male (72.8%) and had type 2 diabetes (91.2%); 84 (73.7%) of patients reported forefoot/midfoot DFO, while 30 (26.3%) reported heel DFO. Patients with heel DFO showed greater rates of soft tissue infection (80 vs 68.7%, p = 0.04), ulcer size >5 cm (93.3 vs 34.3%, p = <0.0001), gangrene (63.3 vs 22.9%, p = <0.0001), higher C-reactive protein values (67.6 ± 25 vs 24 ± 16 mg/dl, p = 0.0002) and concomitant peripheral arterial disease (PAD) (83.3 vs 52.4%, p = 0.0002). Outcomes for heel DFO and forefoot/midfoot DFO were: wound healing (66.7 vs 97%, p = <0.0001), healing time (14 ± 6 vs 6.8 ± 5 weeks, p=<0.0001), major amputation (10 vs 0%, p = 0.0002), and mortality (6.6 vs 4.8%, p = 0.3) respectively. At the multivariate logistic regression analysis, heel DFO [OR 8.4, CI95% (2.1–14.8), p=<0.0001] and PAD [OR 3.5, CI95% (1.1–4.2), p = 0.001] were independent predictors of major amputation, while heel DFO [OR 6.8, CI95% (1.9–10.5), p=<0.0001], PAD [OR 4.8, CI95% (1.4–7.6), p = 0.0001], and ulcer size [OR 1.5, CI95% (1.2–2.6), p=<0.0001] were independent predictors of non-healing. Heel DFO resulted associated with a higher risk of major amputation and reduced chance of healing.