I am 76 and a year of accidents to my already damaged back, a torn rotator cuff in my right shoulder, a broken radius in 4 places in my previously broken left arm and shoulder, etc left me with the same problem. However, a yoga Chair Pose done daily 10 times followed by rising from a sitting position in a straight chair again 10 times daily worked for me. A chair pose is simply sitting with your rear stuck out behind you without touching a chair seat (it’s probably on the internet). I also try to walk 30 mins a day which has revived my leg muscles.
I do understand your desire to avoid surgery. However, from my own experience, postponing surgery can get you to a point where something’s is so far gone that recovery is seriously difficult and painful as it was for my left knee TKR or no longer possible as it is for my S1 and L3-5 spinal stenosis and my torn rotator cuff. I wish you the best and will pray for you. Leslie