Diagnostic Approach for Hip Pain and Limping in Children

Initial Diagnostic Approach

Radiographs of the hip and lower extremities should be the first imaging test for a child presenting with hip pain and limping to rule out fractures, osteonecrosis, or other bony pathologies, as recommended by the American College of Radiology 1, 2
Septic arthritis is a medical emergency requiring urgent diagnosis and treatment to prevent permanent joint damage, according to the American College of Radiology 3, 4

Osteomyelitis may present with hip pain and limp, often associated with septic arthritis, as noted by the American College of Radiology 4, 5
Fracture, particularly spiral tibial fractures ("toddler's fracture"), should be considered in the differential diagnosis, as recommended by the American College of Radiology 2
Juvenile idiopathic arthritis is an inflammatory condition affecting joints that may present with hip pain and limp, according to the American College of Radiology 4

Assess for fever, which raises concern for infection (septic arthritis, osteomyelitis), as recommended by the American College of Radiology 4
Evaluate for history of trauma, as suggested by the American College of Radiology 2
Plain radiographs of the hip and pelvis are the first-line imaging test to evaluate for fractures, Legg-Calvé-Perthes disease, slipped capital femoral epiphysis, and other bony abnormalities, according to the American College of Radiology 1, 2
Ultrasound of the hip is particularly useful for detecting joint effusions and guiding aspiration if septic arthritis is suspected, as recommended by the American College of Radiology 4

If fever present or elevated inflammatory markers, urgent ultrasound of the hip to assess for effusion is recommended by the American College of Radiology 4
If effusion present, ultrasound-guided aspiration for cell count, Gram stain, and culture is suggested by the American College of Radiology 4
Consider MRI if osteomyelitis is suspected, as recommended by the American College of Radiology 4, 5

Pain due to hip pathology can be referred to the thigh, knee, or buttock, leading to misdiagnosis, as noted by the American College of Radiology 2
Negative radiographs do not completely exclude fractures; approximately 10% of tibial fractures are only visible on follow-up radiographs, according to the American College of Radiology 2
Septic arthritis requires rapid diagnosis and intervention to prevent permanent joint damage, as emphasized by the American College of Radiology 3, 4

MRI without contrast should be the next imaging step when plain radiographs are negative or equivocal, as it reliably detects soft‑tissue pathology, cartilage abnormalities, bone‑marrow edema, and early infectious or inflammatory changes that are not visible on radiographs. Evidence level: not specified. [6][7]

Ultrasound is useful only for identifying joint effusions; it has limited value for evaluating deeper structures because of its small field of view and inability to assess deep soft‑tissue pathology. Evidence level: not specified. 8

Hip pathology frequently refers pain to the thigh, knee, or buttock; therefore clinicians must examine and image the hips even when the child points to more distal locations in the lower extremity. Evidence level: not specified. 8