Femoral diaphysis malunion: An overview.

Femoral diaphyseal fractures are commonly treated with intramedullary nailing; however, malunion remains a clinically significant complication, particularly following delayed presentation, non-operative management, or treatment in resource-limited settings. Femoral diaphyseal malunion may be angular, rotational, longitudinal, or multiplanar and can result in gait disturbance, limb-length discrepancy, patellofemoral overload, secondary joint degeneration, and chronic pain. Given the substantial functional impact, corrective osteotomy is often indicated. This narrative review presents a structured approach to the assessment and management of femoral diaphyseal malunion. Key elements include comprehensive patient evaluation, detailed clinical and radiological deformity analysis, and contemporary operative strategies aimed at restoring alignment, rotation, and limb length while minimising morbidity. Successful correction requires meticulous preoperative planning and careful intraoperative execution, according to available resources. Treatment options include intramedullary nailing, plate fixation, hybrid constructs, and external fixation techniques, each with specific indications. Although circular external fixators allow accurate multiplanar correction, their prolonged use in the femur is poorly tolerated. Fixator-assisted correction has evolved to improve intraoperative control while avoiding long-term external fixation. Modern techniques such as Computer Hexapod-Assisted Orthopaedic Surgery (CHAOS) utilise a temporary intraoperative hexapod frame to achieve precise multiplanar correction, followed by definitive internal fixation within the same procedure. Adjuncts including poller screws, three-dimensional planning, and patient-specific guides further enhance accuracy and stability. Femoral diaphyseal malunion presents complex diagnostic and technical challenges. A systematic, patient-specific approach incorporating modern fixator-assisted and computer-guided techniques enables reliable restoration of alignment and rotation, improving function and quality of life.