A few years ago I was stuck in a wheelchair for over 6 months. That's when I bought my Glock 27 subcompact because it was easier to conceal. I took an Uncle Mikes Kydex paddle holster and removed the paddle and attached it to the inside arm of the wheelchair.
Then I practiced drawing and firing from the chair. I practiced shooting from as many different angles as possible. I also practiced shooting strong and weak handed while moving the chair with the other hand.
I wish I'd have taken pictures (I have since removed the holster since I no longer use the wheelchair).
Once on crutches it was a whole different ballgame. I carry on my right hip, so I had to practice balancing with the left crutch, tossing the right crutch, drawing and firing strong hand only (a history of bullseye helped).
Once I graduated to a cane, things became a little easier. I toss the cane and shoot the same as anyone else would. My problem comes with movement scenarios. Squatting, kneeling, diving, or going prone is next to impossible without injury. My tactics here involve side-stepping to cover and accurate fire.
I have been kind of on my own since there are not any training schools in my area. My good friend owns a shooting range close by so that helps with a location to shoot. Some training schools will come to you if you have a large enough class enrollment.
Even Massad Ayoob will come to your location if you meet a minimum enrollment number. I guess you just have to make a lot of inquiries.