Chronic musculoskeletal pain in children: part I. Initial evaluation.

Musculoskeletal pain can be difficult for children to characterize. Primary care physicians must determine whether the pain may be caused by a systemic disease. Change in activity, constitutional symptoms such as fevers and fatigue, or abnormal examination findings without obvious etiology should raise suspicion for rheumatic disease. A complete physical examination should be performed to look for extra-articular signs of rheumatic disease, focusing on but not limited to the affected areas. A logical and consistent approach to diagnosis is recommended, with judicious use of laboratory and radiologic testing. Complete blood count and erythrocyte sedimentation rate measurement are useful if rheumatic disease is suspected. Other rheumatologic tests (e.g., antinuclear antibody) have a low pretest probability in the primary care setting and must be interpreted cautiously. Plain radiography can exclude fractures or malignancy; computed tomography and magnetic resonance imaging are more sensitive in detecting joint inflammation. Family physicians should refer children to a subspecialist when the diagnosis is in question or subspecialty treatment is required. Part II of this series discusses rheumatic diseases that present primarily with musculoskeletal pain in children, including juvenile arthritis, the spondyloarthropathies, acute rheumatic fever, Henoch-Schönlein purpura, and systemic lupus erythematosus.