Trauma or overuse Fracture Osteochondroses Stress fracture Soft tissue injury Spondylolisthesis Herniated nucleus pulposus Infectious Septic arthritis Osteomyelitis Lyme arthritis Discitis Epidural abscess Appendicitis Pelvic inflammatory disease Deep cellulitis/abscess Inflammatory Transient synovitis Reactive arthritis Rheumatic disease Myositis Chronic recurrent multifocal osteomyelitis (CRMO) Developmental or acquired Developmental dysplasia of the hip Blount disease Limb-length discrepancy Torsional deformities Avascular necrosis Slipped capital femoral epiphysis Testicular torsion Congenital Vertical talus Tarsal coalition Other congenital limb abnormalities Spinal dysraphism