Chronic Overuse Injuries in Young Athletes-Upper Extremity

Young athletes are uniquely susceptible to overuse injuries of the upper extremity because their open physes and apophyses are structurally weaker than adjacent bone, ligament, and tendon. Repetitive sport-specific loading-torsional stress in throwers, axial compression in gymnasts and climbers-can outpace the repair capacity of growing tissues, producing a spectrum of physeal and apophyseal stress injuries from widening and sclerosis to frank epiphysiolysis. This review examines the mechanisms, clinical presentation, and imaging findings of chronic overuse injuries at key upper extremity sites, including the proximal humeral physis (Little Leaguer's shoulder), glenoid and coracoid, acromion, medial epicondyle (Little Leaguer's elbow), capitellum, olecranon, distal radius (gymnast's wrist), and finger phalanges of adolescent climbers. Emphasis is placed on MRI for early detection, differentiation from normal developmental variants, and guidance of management to prevent growth disturbance.