Hybrid Illizarov Fixation for Atrophic Nonunion Following Failed AO External Fixation of Open Humerus Fracture – A Case Report

Abstract

Background: Atrophic nonunion of the humerus is a challenging condition, especially following failure of conventional fixation methods such as the AO external fixator for open fractures. The Ilizarov technique provides a biologically favourable mechanical environment for bone healing in such complex cases. Case Presentation: A 35-year-old male presented with atrophic nonunion of the midshaft humerus, six months after a failed AO external fixator application for an open humerus fracture. The patient had a restricted range of motion, pain, and functional disability. Radiographs revealed hypertrophic callus absence and a significant bone gap. The patient was managed with a hybrid Ilizarov external fixator incorporating both Schantz pins and half rings for optimal stability. Union was achieved at 4 months. Conclusion: This case highlights the utility of hybrid Ilizarov fixation in complex nonunions, the critical role of accurate classification using Weber-Cech and Paley systems, and the importance of restoring both mechanical and biological environments for bone healing. Hybrid Ilizarov fixation offers a viable salvage treatment for atrophic nonunion of the humerus, especially after failure of previous fixation. It provides stable fixation, stimulates osteogenesis, and allows early rehabilitation.