Rotator Cuff Muscles The rotator cuff is a group of muscles and tendons that both articulate and stabilize the shoulder joint. Despite their small size and relative lack of strength, they play a crucial role in upper body movements. ▪️ Supraspinatus at the top contracts to initiate the lifting of your arm out to the side (abduction) ▪️ Teres Minor on the back contracts to create lateral rotation and stabilization ▪️ Infraspinatus on the back side contracts as you wind up, preparing to throw a ba