Upper Back Pain

I was doing some rack deadlifts at my gym tonight. On my last set, I felt a considerablly sharp pain on the upper right side of my back (around my teres minor/infraspinatus). I lifted my arm up to feel the area where the pain originated. The area felt hard as a rock and quite stiff. I am concerned that I might have strained/possibly torn something in that area.

It does not hurt much currently, but the area is quite stiff.

Any suggestions for methods to remedy this and/or avoid more serious injuries in the future?

Any suggestion is greatly appreciated.

see if it is injured beyond just tightness. If it is just tightness and the pain starts to subside, break out a racketball. get very familiar with it. roll around the back of your arm right at those rotator cuff muscles.

thank you for your response. What method of rehabilitation would you suggest I begin if the pain does not subside?

I think if you can use the arm in regular activities, the pain does not require surgery. If you think you torn something, get it looked at. If all comes back clear, then begin the work on it right away, and after each session, stretch the muscles. Also stretch the muscles multiple times a day to get movement back that is no doubt lost.