Prolo is a good treatment to tighten up the shoulder capsule.
I just had my shoulder done 2 days ago, and my doc pointed out that my pain was being caused by an imingement due to a laxed joint. He hit both the front and back of the shoulder capsule to begin to tighten it up.
You will find that Prolo DOcs are always trying to treat the cause of pain and dysfunctioning joints, not just the pain.
I cant recommend it too much. Zyg and Buffdoc are also up on prolo as well.
Good luck!!