Physiotherapist vs. Personal Trainer?
Physiotherapy and physical therapy are the same as far as I can tell. Your experience as a personal trainer should greatly enhance your base skill set which should correlate well with a physical therapy education.
Physical therapy is a health care profession, a little beyond the expertise of a personal trainer. However, the two disciplines have a lot in common and should integrate well. Both require a love for maximizing quality of life for the client.
PT works on balance issues, orthopedic/musculoskeletal injuries and requires evaluating strength, flexibility and ROM. These are much the same as addressed in Personal Training.
Combining these two doctrines you should be able to identify a niche where you can become the “expert” and serve a small, focused audience who require you specialized brand of service. I believe you are making a wise decision and wish you the very best.