I used to play a lot of squash back in the day, and i had severe shoulder ligament impingement problems. Any activity (throwing, most racquet sports) that have a very fast deccelerating component make your shoulder joint very vulnerable and prone to injury.
I had dislocated my shoulder twice and sufferec from acute impingement of some of my shoulder ligaments. Physiotherapy really helps, but one thing that became my best friend after was "tubing."
The way tubing works is that it increases strength at end Range of Motion, making the joint less susceptible to repeated injuries and also strengthens the ligaments. See if you think about it, in weight training, the way lever arms work and the way weight are lifted, you usually lift less and slower at end ranges of motion. The lever arm is usually shorter and so the torque generated by a muscle is less.
Tubing, is opposite, because tension in the weight increases as the tube is stretched.
Also, after the injuries, i can do dumbell presses fine, but have a tough time doing military barbell presses, so i use the smith machine.
Remember, if you feel any pain doing any exercise, stop!!!!
Work yourself back slowly, very slowly, because reinjury will cost you more time and headaches.
If you want to know more details etc. just PM me
Good luck, its a hard way back to recovery, but you wil recover close to 100%.