Limb Salvage After Chronic Nonunion Following Deformity Correction in Congenital Fibular Deficiency: A Cautionary...

Background: Congenital fibular deficiency is a rare longitudinal deficiency of the lower extremity associated with limb-length discrepancy, ankle and foot deformity, soft-tissue imbalance, and functional impairment. Reconstruction may be challenging because bone healing, regenerate maturation, and mechanical stability can be less predictable in selected patients. Case Presentation: A man with congenital fibular deficiency developed chronic distal tibial nonunion after corrective osteotomy at another institution. The nonunion persisted for four years, and the patient presented to our hospital with inability to bear weight and wheelchair dependence. A comprehensive salvage strategy was performed, including Achilles tendon lengthening using the Vulpius technique, removal of retained fixation material, debridement and refreshment of the nonunion site, negative bacteriological cultures, autologous cancellous iliac bone grafting, acute shortening and compression of the docking site, circular external fixation, proximal tibial osteotomy, and gradual lengthening. Low-intensity pulsed ultrasound was applied postoperatively as an adjunctive biological stimulus. Results: Bone union was achieved, and the external fixator was removed approximately one year after surgery. A total lengthening of 78 mm was achieved. At 12-year follow-up, the AOFAS ankle-hindfoot score was 90, ankle range of motion was 5° dorsiflexion and 40° plantarflexion, and the JOA knee score was 95. The patient walked independently without assistive devices and continued to work. Mild residual varus deformity of the proximal tibia was present, but the patient reported no knee pain, ankle pain, or ankle instability, and radiographs showed no progressive osteoarthritic changes. Conclusions: In selected patients with congenital fibular deficiency and chronic nonunion after previous treatment, durable limb salvage may be achieved using an individualized strategy that addresses both biological and mechanical factors.