Congenital anomalies and vascular birthmarks of the lower extremities.

MR imaging is an invaluable tool for the evaluation of congenital abnormalities and vascular birthmarks of the extremities in children. These abnormalities of the immature musculoskeletal system are often underestimated by radiography. MR imaging is useful for diagnosis, assisting in therapy, showing response to treatment, and determining prognosis. Localized and generalized abnormalities of the lower extremities and issues pertinent to their MR imaging are illustrated in this article.