Musculoskeletal Injuries of the Upper Extremity
Shoulder
Know the anatomy of the rotator cuff, labrum, and glenohumeral stabilizers. Differentiate impingement, rotator cuff tendinopathy, SLAP tears, and instability. The apprehension/relocation test assesses anterior instability; the Neer and Hawkins tests assess impingement. Trap: confusing AC joint separation (point tenderness, step-off) with clavicle fracture (deformity, crepitus).
Elbow
Medial epicondylitis (golfer's) versus lateral epicondylitis (tennis); valgus extension overload in throwers causes ulnar collateral ligament injury. The moving valgus stress test and milking maneuver assess the UCL.
Wrist and hand
Scaphoid fracture is the most commonly missed carpal injury-snuffbox tenderness warrants immobilization and imaging even with normal radiographs. Distinguish de Quervain tenosynovitis (Finkelstein test) from thumb base arthritis. Gamekeeper's thumb is a skier's thumb UCL injury at the MCP joint. Jersey finger is flexor digitorum profundus avulsion; mallet finger is extensor avulsion.
Rule of thumb
Snuffbox tenderness = treat as scaphoid fracture until proven otherwise. For throwers with medial elbow pain and valgus instability, suspect UCL injury and refer for advanced imaging.