MR imaging of the shoulder in youth baseball players: Anatomy, pathophysiology, and treatment.

Overview

With an increasing participation in youth sports and a growing popularity of overhead sports, shoulder pain and injuries are common in pediatric baseball players. In contrast to traumatic and collision injuries, which are more frequent with high-impact sports, many of the shoulder injuries are the result of repetitive overuse. Undiagnosed and untreated injury to the growth plates of skeletally immature athletes can lead to remodeling, which can negatively impact the biomechanics of the shoulder and produce long-term morbidity. Recently, there is an increasing emphasis on the association between skeletal maturation and injury patterns. The increasing use of magnetic resonance (MR) imaging has led to a better characterization of the traditionally radiographically-diagnosed growth plate injuries and awareness of other soft tissue and cartilaginous injuries that were previously thought to predominately occur in adult baseball players. The goal of this review is to: 1) highlight the normal anatomic changes that occur in the shoulder girdle during development and maturation; 2) discuss the biomechanical forces that are applied to the shoulder during a pitch; and 3) highlight the various injury patterns and adaptive remodeling that can occur in the shoulders of youth baseball athletes along with the current treatment options. These topics include growth plate injury, osteochondral injury, labral tear, capsular remodeling and rotator cuff tendinopathy.