MR arthrogram findings of luxatio erecta in a pediatric patient-arthroscopic confirmation and review of the literature.

Abstract

Luxatio erecta or inferior glenohumeral dislocation is a rare type of shoulder dislocation, accounting for less than 1 % of all reported shoulder dislocations. We describe a 15-year-old male who presented with luxatio erecta following an injury to his shoulder that resulted from a mountain biking accident. Clinically, the patient had shoulder pain and fixed abduction of the arm. Radiographs confirmed the diagnosis of luxatio erecta. A magnetic resonance arthrogram (MRA) performed 9 days after presentation demonstrated both a greater tuberosity fracture and avulsion of the anterior and posterior inferior glenohumeral ligaments from their humeral attachment. The MR findings were confirmed on arthroscopy. The bone and soft tissue injury pattern seen in our patient clearly supports the described mechanism of injury for luxatio erecta and lends credence to the theory that a fracture of the greater tuberosity spares injury to the rotator cuff, especially in children. A review of the literature failed to reveal any prior description of the MRI or MRA findings of luxatio erecta in a pediatric patient or any publication with arthroscopic confirmation of the MR findings.