Just to throw out an idea but if you have to use crutches have you thought of maybe getting something that would strap onto one of the crutches. I think that would be pretty easy to do.
I actually have thought of that. One time, at one of my ortho appts there was a teenager there that was on crutches and it looked like she had been on them awhile. She had taken colored string of some kind and had covered her crutches with the brightly different colored strings. They were some great looking crutches, really showed her spirit.
I have a couple of handlebar grips that I might have to get out and see if I can get creative.

I never use a pattern I just look at what I need and make it. I added pockets for cartos and atties. A pocket could also be added for a juice bottle. I thought it was better than keeping my Chuck in my bra.