Functional and Radiological Outcome of Shaft Humerus Fracture Treated By Extension Cast

Introduction: Shaft humerus fractures, accounting for 3% of all fractures, are typically caused by falls, sports injuries, or road traffic accidents. While various operative techniques are available, nonoperative methods like extension casting, based on functional bracing principles, are effective and widely practiced. These methods promote fracture healing by preserving the biological environment, offering high union rates with minimal complications. Material and Methods: This prospective observational study included patients aged 18-65 years with closed shaft humerus fractures (AO/OTA classification 12-A and 12-B), treated using an extension cast under fluoroscopic guidance. Functional and radiological outcomes were assessed using DASH and Constant-Murley scores over a 6-month follow-up, with results statistically analyzed for significance. Results: Shaft humerus fractures were most common in individuals aged 41-50 years (28%), with a male predominance (64%) and the middle shaft being the most frequently affected region (44%). Clinical, functional, and radiological outcomes varied across age groups, with older patients showing longer union times and slightly reduced composite movements. When outcomes were analyzed by sex, males had better composite shoulder and elbow movements, which were statistically significant, while time to union and angulation showed no significant differences. Based on topographical type, middle shaft fractures demonstrated the shortest time to union and superior composite movements, with statistically significant differences in elbow movement (p = 0.048). Morphological comparisons showed no significant differences in union time, but intermediate fractures had better composite shoulder movement (p = 0.027), highlighting the influence of fracture characteristics on recovery outcomes. Conclusion: The shaft humerus fractures treated with extension casts demonstrated favorable clinical, functional, and radiological outcomes, with union rates influenced by age, sex, topographical type, and fracture morphology. Middle shaft fractures and intermediate morphologies showed better overall recovery, emphasizing the importance of individualized treatment approaches.