I dislocated my right shoulder in 2000. This did for the rotator cuff..and ripped the axilliary nerve, too. I fought furiously to get surgery to repair the rotator cuff, and was finally successful, Coming to in the recovery room I heard the surgeon say "In the end we didn't proceed with the repair...." which really cheered me up. I was later told "It isn't a vastly successful operation, anyway"... The nerve took months to regrow. Physiotherapy was of limited effectiveness...couldn't get the arm above shoulder height. So I got a pulley and some rope and weights...and that counterbalanced the weight of the arm, so that I could raise it above my head. Bit by bit I reduced the counterbalance until I could raise the arm unaided. I still have problems trying to do such things as reaching up with a hammer and bashing things.... but the arm is quite usable now.
Then in 2014 I dislocated the left shoulder....(!)