I dont know about old wounds but there are some recent development that is really interesting.
Just a couple of years ago we thought that knee-pain was necessary, that was until the "knees-over-toes-guy" understood that lifting with your knees extending over your toes is the only thing that strengtens, not hurts it (at least in a particular way!?!?) Which was what was spread far and wide and in every strata of society for decades, thereby eliminating the only cure there was for hurting knee... but is this the same for wounded shoulder.. i want to guess i know but i dont. If it was someone who would know if it helps or not - its him. He is shoulder (heh) above "everyone" else - there are some who also have renown, but I dont know their names on the top of my head...
Check out "knees over toes guy", he had a lot of surgery but it didnt help. He knows alot about everything, and has contact and experience with a lot of people that rehabilitates.. his regime which is mainly for free, but I think you can contact him through an app if you pay a certain fee or something, and he should have more experience concering all kinds of these problems. Check him out!
Or just take the risk of letting me teach you (and then we learnt that in that particular instance... it just made everything worse! lol)