Im on HRT so I have been taking Test E for over 3 years. Only think it has done for my back (2 back surgeries due to rupture L3, L4 & L5/S1) is help get back in shape and strengthen up. I find that is the key and biggest help. Of course I was told to NOT lift, especially dont do squats or dead lifts but I find doing them properly, light weights and listening to my body it helped with the back a lot and they doctor has said since then to just keep doing whatever I'm doing. I'm not saying it's a cure all, I still have back issues, pain, numbness, limited mobility to a point but I know it would be a lot worse if I was not working out.
The deca did not seem to do much for me as in joint recovery. It did nothing for my back at least but I didnt have any shoulder issues at the time. Honestly though I also have serous doubts on the quality of the Deca due to very lack luster gains. I think most of the gains were due to my T increase. Only think that makes me think the Deca may have been real was after the cycle things just didnt feel quite the same. Everything worked fine and still does but the libido just didnt seem the same and it took longer to get things done.
I know it was 3 or 4 weeks into using the winstrol that both my shoulders tweaked at the same time and I was not lifting heavy.

I wont use it again. I had problems with my right one before due to an accident cracking the ball and of course rearing the rotator cuff lining but never with my left shoulder. The right one has gotten mostly better but the left is still a big problem.
I hear you on wanting to get back faster. I have been looking into other things the last couple of years due to my back and old shoulder problems mostly being tendons issues now. There seems to be quite a bit for animals, dogs and horses when it comes to ligament repair but next to nothing for people. Look into Adaquen or Alflutop. There is some interesting information out there. I cant say personally if either of these work but a lot of people seem to think so.