I can only echo Pearson even though I believe that a physical therapist’s scope goes way beyond what a personal trainer does.
There was only one caution that I have: make sure you have everything cleared well with liability insurance. When you have a client relatioinship as a personal trainer and only have the corresponding insurance: where is your scope of practice and what can you be held liable for when you also act as a physical therapist? I really don’t have an answer to that but my gut feel tells me that you need to investigate this issue very carefully.
I wish you best of luck!