ive had my fair share of injuries, im only 27 but my competitive days are gone with my shoulder and knee issues,,, just try and look on your training in a different light when u get back, ditch anything high risk..
For example,if its your knees, stop squating and just pump out on leg extensions and do small movements on the leg press... pre exhaust everything, do supersets, higher reps, less time between sets etc etc... dont go chasing weight or youl spend more time injured than u will training.. just remember, a little of somthing is better than nothing.
I do think some structures are more injury prone than others, my younger brother is starting to develop the same problems that i had