RESUMO
Overuse elbow injuries in young throwing athletes are generally defined as 'Little Leaguer's elbow'. Repetitive submaximal valgus forces on the medial epicondylar apophysis in such athletes can result in apophyseal separation or chronic apophyseal fragmentation, which would usually take over more than a year to heal. We report of a unique case of a 13-year-old male baseball pitcher who, due to the traction of the medial collateral ligament, presented with an acute intra-apophyseal avulsion fracture of the medial epicondyle. The fracture was successfully healed using a long arm cast, and correct union was confirmed by 3 dimensional computed tomography at 8 weeks post-trauma. This acute avulsion fracture is a variant of Little Leaguer's elbow and should be distinguished in terms of diagnosis and treatment from common lesion such as chronic fragmentation of the medial epicondylar apophysis.