I used to have constant shoulder pain, very dull, low level, but enough to make it uncomfortable sleep at night.
I started doing these exercises a few years ago and have never had problems since:
I dont know what they are called, but i will describe them...
take a dumbbell, very low weight, 5 or 10 lbs.
put your arm straight to the side, then bend your elbow up 90 degrees. so now your in like a bicep pose. this is the starting position.
now keep the elbow locked at 90, but rotate the shoulder forward, bring the weight down, then raise it back up. done.
good for the rotator cuff.
other low weight shoulder exercise on the cable machine:
put cable at elbow level, left shoulder to machine, take grip in right hand. elbow bend 90 degrees, righ hand extending across stomach, keep upper arm tight along body. rotate right shoulder, pulling grip out from machine, you should get about 130 degrees of rotation.
together these exercise eliminated all my shoulder pain by strengthening the rotator cuff, which is often a culprit in shoulder pain.
I hope this helps!
by the way, what the hell are these exercises called?