Musculoskeletal Emergencies and the Limping Child
Musculoskeletal complaints require a systematic approach: inspect for swelling, deformity, and symmetry; palpate; and always perform a neurovascular and vascular exam distal to the injury, documenting it before and after any intervention. Pediatric fractures differ from adult ones because of the physis and the thick periosteum. Know the Salter-Harris classification (SALTR: I Slipped, II Above, III Lower, IV Through, V cRush) and that Type I and V injuries may be radiographically silent and treated on clinical suspicion alone.
High-risk injuries
The supracondylar humerus fracture is the most common elbow fracture in young children and the most dangerous: it threatens the brachial artery and anterior interosseous nerve. A "pink, pulseless" hand after reduction still needs urgent orthopedic evaluation. Orthopedic emergencies to recognize on the exam include open fractures, compartment syndrome (pain out of proportion, pain with passive stretch, pallor, paresthesia, pulselessness - the 6 Ps), and a limb that is pale, cool, or painful after a cast.
Limp and atraumatic pain
Distinguish septic arthritis from transient synovitis using the Kocher criteria (fever, refusal to bear weight, elevated ESR, elevated WBC); septic arthritis demands joint aspiration and drainage. A limping child with hip or knee pain needs consideration of Legg-Calvé-Perthes and slipped capital femoral epiphysis (obesity, adolescence, external rotation). Nursemaid's elbow occurs in children under 5 after a pull; reduction via supination and flexion is straightforward, and radiographs are usually unnecessary. Growing pains are bilateral and night-time; unilateral persistent pain is never growing pains.
Red flag: a femur fracture or spiral rib fracture in a nonambulatory infant suggests abuse until proven otherwise - report and document.