He earned his medical doctorate at Creighton University in Omaha, Nebraska and completed his internship at the University of California, Los Angeles Medical Center, then completed his Orthopaedic Surgery residency at LAC + University of Southern California Medical Center. He completed his Sports Medicine Fellowship at Kerlan-Jobe Orthopaedic Clinic, a founding partner of the Cedars-Sinai Kerlan-Jobe Institute. Dr. Shields is an Associate Clinical Professor in the Department of Orthopaedic Surgery at USC and Assistant Clinical Professor at the Charles R. Drew University of Medicine and Science. He is an orthopaedic consultant to the University of California, Irvine Medical Center and Rancho Los Amigos Hospital. Dr. Shields is a Neutral Physician for the National Football League and is the former orthopaedic consultant to the Los Angeles Rams.