The rotator cuff is a group of muscles and tendons extremely important for the function of the shoulder. Tearing of the rotator cuff tendons represents one of the most common reasons of shoulder pain, weakness and poor function (Acute Tears of the Rotator Cuff: Why seek Help Immediately?; A Few Common Questions About Rotator Cuff Tears: … More A tiny nerve in the shoulder can create so much trouble! All you need to know about the suprascapular nerve