Wow, that was amazing progress. If you did it once, you can definitely do it again. I have also lost a lot of weight and then put it on again. I have learned that when I stop tracking my food, I go back to bad habits and bad choices. It's a real pain to constantly be inputting food info, but it keeps me honest. Weight is about 80% diet and 20% exercise, so if your injuries prevent you from exercising, then focus harder on diet. I have a lot of health problems even though I'm not that old, and sometimes can't exercise as much as I would like either, but I try to get something in at least 5 days a week. Maybe you could switch to something different on bad days - just work on your arms, or just walk slowly, or get a stationary cycle, or gentle yoga - whatever low impact exercise wouldn't aggravate your problems. I put in as hard as I can when I feel good, and cut myself some slack when I feel awful.
Bohemian and adrienne121 like this comment.