Many assume that the only reason to visit an orthopedic surgeon (specialist) is for surgery, but that's simply not the case. Orthopedic doctors specialize in the musculoskeletal system: the muscles, nerves, bones, joints, and connective tissues. They see patients with a variety of conditions such as arthritis, bursitis, osteoporosis, tumors, pain (such as knee pain, hip pain, joint pain, and muscle pain).