[Physioguy]

Some great replies in this thread. Hopefully you have received a diagnosis.

I will piggy back on Vickie's comments. I have an interest in shoulders (having dislocated my own a few years back), and what I commonly see is that the shoulder blade gets "out of synch" with the arm. The shoulder blade relies heavily on the musculature around it, as its only connection to the skeleton is at the sternum, through the collar bone.

What I tend to see is significant tightness around the shoulders, typically involving the pecs, lats, and one of the rotator cuff muscles (subscapularis), and often weakness of the muscles between the shoulder blades. To make matters worse, there is commonly poor posture, associated with a head-forward carriage, and rounded forward shoulder girdles. This is more common than you may think.

What then happens is that the shoulder blade doesn't rotate in synch with the upper arm, particularly with overhead and elevation movements. When this happens, you can often get a pinching (impingement) of the shoulder rotator cuff muscles. I shouldn't neglect to mention that a fully functioning shoulder requires decent mobility of the upper thoracic spinal (upper back) segments, and this is another area that gets quite stiff.

Like most injuries, once it has settled down, proper rehabilitation should include stabilization exercises. Stabilization is simply the ability to control whatever mobility you have. From what I mentioned above, the first thing I usually work on is mobility of the shoulder girdle muscles. As the mobility comes, you strengthen/stabilize it with appropriate exercise.