Criterios radiográficos para la reducción rotatoria en fracturas diafisarias de húmero

Introduction: Humeral shaft fractures are frequent and surgical treatment is currently favored. Consolidation in malrotation is a complication that can lead to impaired function and long-term osteoarthritis. In minimally invasive techniques, it is difficult to manage intraoperative rotation as there is no direct view of the fracture reduction. Objective: To describe radiological criteria for rotational reduction in humeral shaft fractures. Materials and Methods: Retrospective study of humerus radiographs comparing radiological criteria of the distal humerus between radiographs with internal rotation (without proximal retroversion) and radiographswith external rotation (with physiological retroversion). Criteria studied: Overprojection of the lateral epicondyle over the capitellum of more than 50%; sclerosis of the lower border of the olecranon fossa (OF); sclerosis of the lateral border of the OF; and asymmetry of the OF. Results: 200 radiographs were studied; 97% met the inclusion and exclusion criteria. Overprojection ofthe epicondyle over the capitellum was found in 83.3% of the cases. Sclerosis of the inferior border of the OF in 30%, sclerosis of the lateral border of the OF in 86.6%, and asymmetry of the OF in 80%. All criteria were statistically significant (p<0.001). When analyzing the 3 positive signs, we found a sensitivity of 70% and a specificity of 98%. The positive predictive value was 95.5% and the negative predictive value was 84.5%. Conclusions: Correct humeral rotation is difficult to reproduce when performing minimally invasive surgeries in patients with a diaphyseal fracture. We describe 4 radiological criteria that allow inferring a correct humeral rotation.