you picked in interesting example because I have a client almost like that – without carpal tunnel (and I am confident that I would have been able to work around that one as well).
Of course, I obtained a physician’s approval, and then I did what I do with every client: assess, observe, interact, communicate and find the path that will help the client get to a better place without aggravating any of the complications.
If I find myself in a situation like that, I try to break it down into manageable parts. I am often familiar with the individual problems, and may only deal with one at a time.
Frankly, referring out is often not possible. In all modesty, I would not have known where to refer the client. She has made significant progress to the astonishment of her health care providers and found myself in a position where I explained to the doctors my approach.
This was a situation which I was comfortable with. However, I like to think that I also know when I am over my head.