What's the difference between an orthopedic and a physical therapist?

Different training. An orthopedic surgeon is trained in disease of the joints and bones. A physical therapist is usually not a physician. Physicians trained in that area are physical medicine specialists. The last to field are involved in the rehabilitation of patients with many diseases.
Orthopedic vs PT. Orthopedic surgeon is md or do surgeon. Pt has ms or doctorate in physical therapy. Orthopedist can rx medications.