Orthopedic Physician Associates (Seattle). Orthopedic Physician Associates includes two practices, one in Seattle and a newly-opened location in Issaquah. The physicians are board-certified in orthopedics and each has advanced subspecialty fellowship training in sports medicine, joints, foot and ankle, spine or trauma. OPA also has diagnostic services, including MRI and diagnostic X-ray equipment. E. Edward Khalfayan, MD, is among the only physicians in the country to serve as a head team physician for both a National Football League and a Major League Baseball team, the Seattle Seahawks and Mariners.