Circular external fixation for reverse sural flap protection after partial calcanectomy in a diabetic heel with distal tip necrosis

Reverse sural artery flaps are susceptible to venous congestion, while posterior heel coverage requires strict protection from pressure. A 48-year-old woman with poorly controlled type 2 diabetes, anaemia and chronic calcaneal osteomyelitis had a persistent 4×5 cm left heel defect. Magnetic resonance imaging showed acute-on-subacute osteomyelitis with an intraosseous abscess. After multidisciplinary preparation, partial calcanectomy and a pedicled reverse sural flap with split-thickness skin grafting were performed. A circular external fixator was configured to suspend the heel, protect the pedicle and permit wound surveillance. The flap remained viable, but repeated supine positioning was followed by congestion and, at one month, 1 cm distal tip necrosis that was debrided and resutured. At 10 weeks, the flap was well settled with a residual 2×4 cm healing distal wound. Circular fixation can provide contact offloading and access, but does not replace positioning, congestion surveillance, metabolic optimisation and structured follow-up.