Isolated Avulsion of Extensor Carpi Radialis Longus and Brachioradialis Origins: A Case Report and Surgical Repair Technique.

The mobile wad of the elbow provides a tremendous mechanical advantage with respect to elbow flexion and wrist extension. Injury to these structures causes significant upper extremity dysfunction. In this article, we report the case of a 31-year-old right hand-dominant man who sustained an isolated avulsion of the extensor carpi radialis longus and brachioradialis origins from the lateral epicondyle and lateral supracondylar ridge. We describe our diagnostic workup and present our surgical repair technique. The literature includes only 2 case reports of bony avulsion fracture of the origin of the brachioradialis and, up until now, no case reports of isolated avulsion of the extensor carpi radialis longus and brachioradialis origins. Given the biomechanics and anatomy of the dorsal mobile wad, we posit that our patient's injury occurred secondary to an overwhelming eccentric muscle contracture. The rarity of this injury led to a substantial delay in diagnosis. Because of the potential morbidity, surgical intervention is recommended.