The greater and lesser tubercles of the humerus provide attachment points for the muscles of the rotator cuff, a group of four distinct muscles: the supraspinatus, infraspinatus, teres minor, and subscapularis. The muscles connect the scapula to the head of the humerus, forming a cuff at the glenohumeral joint. The rotator cuff muscles are used for flexion, abduction, and internal and external rotation of the arm. The muscles are all used when lifting the arm overhead, as their resultant force serves to pull the humeral head into the glenoid cavity and stabilize the joint.
