Lower leg pain in a 17-year-old boy.

From the 1 Clinical Research Coordinator, Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA; 1 Attending Physician, Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA; 1 Attending Radiologist, Department of Radiology, The Children's Hospital of Philadelphia, Philadelphia, PA; 1 Assistant Professor of Pathology and Laboratory Medicine University of Pennsylvania Staff Pathologist, The Children's Hospital of Philadelphia, Philadelphia, PA; and 1 Chief, Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA.