Nonunion in Long Bone Fractures: A Comprehensive Review of Current Treatment Strategies.

Nonunion is a significant complication of long bone fractures, occurring when bone healing fails to progress despite adequate time and appropriate initial management. This condition affects a significant proportion of fractures, with rates varying considerably based on the anatomical location, fracture pattern, patient factors, and treatment methods. The management of nonunion remains challenging and requires a comprehensive understanding of the mechanical and biological factors influencing bone healing. This narrative review systematically examines the current treatment options available for managing nonunion in long bone fractures, including both nonoperative and operative approaches. Nonoperative management encompasses the optimization of patient factors, pharmacological interventions, and biophysical stimulation techniques. Operative treatment strategies include revision internal fixation, bone grafting, biological augmentation with growth factors, distraction osteogenesis, and vascularized bone transfer. The selection of an appropriate treatment modality depends on multiple factors, including the type of nonunion, anatomical location, presence of infection, bone quality, soft-tissue condition, and patient comorbidities. Recent advances in surgical techniques, biological augmentation, and fixation devices have improved outcomes; however, successful management fundamentally requires restoration of mechanical stability combined with enhancement of the biological environment. This review synthesizes the current evidence regarding various treatment modalities, their indications, techniques, outcomes, and complications, providing a practical framework for clinicians managing this complex orthopedic problem.