Hope you get to the bottom of it soon!

Sounds like you still have lots of options for maintaining fitness:

• pretty much any upper body exercises
• bodyweight single-leg squats?
• if you can get to a cheap gym you've got a myriad of resistance machines available they don't need balance etc..but maybe cost is an issue.

Anyway I'm sure you've thought of all of this - just know this one stranger wants you to be able to lead a healthier life soon!