The acutely limping child

Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.     

The chronically limping child

Chronic limping in children usually indicates the presence of an underlying organic lesion. Clinical evaluation establishes the site and type of limping. It may suggest a neurological or mechanical lesion or locoregional etiology at the level of the hip or pelvis. Plain radiographs and ultrasound are firstline imaging techniques. The diagnosis may be delayed either due to ignorance of age-specific entities or false positive or negative results on plain films and ultrasound. MRI now plays a major role for diagnosis. Multiple potential underlying etiologies including trauma, infections, arthritides or tumors are best evaluated with MRI. The MRI examination should not be limited only to the hip joint.