Coronal shear fractures of distal humerus: Diagnostic and treatment protocols

Coronal shear fractures of distal humerus involving the capitellum and the trochlea are rare injuries with articular complexity, and are technically challenging for management. With better understanding of the anatomy and imaging advancements, the complex nature of these fractures is well appreciated now. These fractures involve metaphysealcomminution of lateral column and associated intraarticular injuries are common. Previously, closed reduction and excision were the accepted treatment but now preference is for open reduction and internal fixation with an aim to provide stable and congruent joint with early range of motion of joint. Various approaches including extensile lateral, anterolateral and posterior approaches have been described depending on the fracture pattern and complexity. Good to excellent outcome have been reported with internal fixations and poor results are noted in articular comminution with associated articular injuries. Various implants including headleass compression screws, minifragment screws, bioabsorbable implants and column plating are advocated for reconstruction of these complex fractures. Inspite of articular fragments being free of soft tissue attachments the rate of osteonecrosis and osteoarthritis is reported very less after internal fixation. This article summarizes the diagnostic and treatment strategies for these rare fractures and recommendations for management.