CLINICAL AND FUNCTIONAL OUTCOMES OF CHRONIC CALCANEAL DIABETIC OSTEOMYELITIS TREATED WITH A PARTIAL CALCANECTOMY WITH ANTIBIOTIC-LOADED CALCIUM SULPHATE HYDROXYAPATITE BIOCOMPOSITE APPLICATION VIA THE SILO TECHNIQUE

Introduction: Partial calcanectomy is an established alternative to amputation in diabetic calcaneal osteomyelitis, with recent studies utilising adjuvant local antibiotic delivery devices to improve outcomes. The Silo technique is a novel approach involving an antibiotic-loaded hydroxyapatite calcium sulphate bioceramic (Cerament G or V) implanted into pre-drilled holes in the calcaneum. Method: This retrospective case series involved 30 patients with chronic diabetic calcaneal osteomyelitis that underwent partial calcanectomy with Cerament G or V application via the Silo technique between 2014 and 2024. Patients were also followed up on their mobility via telephone consultation. Primary outcomes were infection eradication, ulcer healing, limb salvage, patient mortality and ambulatory status. Results: Infection eradication was achieved in 29 (97%) patients, ulcer healing in 27 (90%), ulcer recurrence in 8 (26.7%), and limb salvage in 28 (93.3%). The all-cause mortality rate was 6.7% at 1-year and 43.3% at 5-years. From baseline, 6 (20.0%) patients improved their mobility status, 20 (66.7%) maintained their mobility status, and 4 (13.3%) deteriorated in mobility status. Conclusion: This is the second study to report on outcomes of the Silo technique and has demonstrated good clinical outcomes in infection eradication, ulcer healing, ulcer recurrence, limb salvage, 1-year mortality, and mobility. However, there was a high 5-year all-cause mortality rate. Further studies are warranted to assess the efficacy and factors affecting outcomes.