[1] Drexel Univ, Coll Med, 60 N 36th St, Philadelphia, PA 19104 USA
[2] Allegheny Gen Hosp, Dept Diagnost Imaging & Radiol Allegheny Hlth Netw, 320 East North Ave, Pittsburgh, PA 15212 USA
[3] Allegheny Gen Hosp, Allegheny Hlth Network, Dept Orthopaed Surg, 320 East North Ave, Pittsburgh, PA 15212 USA