Growth arrest and leg-length discrepancy.

Identification of congenital and acquired etiologies causing alignment disorders and leg-length discrepancies (LLD) in children is important for management. Minor differences in the lengths of the lower extremities are considered a normal variation and usually have no clinical significance. However, LLD of greater than 1 cm can cause altered biomechanics, resulting in scoliosis, back and lower extremity joint pain, pelvic tilt, abnormal gait and premature degenerative joint disease. The purpose of this pictorial essay is to review the imaging spectrum of growth arrest and resultant alignment and leg-length discrepancies in children.