Rotator cuff exercise device

An apparatus, comprising:

• a plate comprising an internal side configured to be secured against a torso of a person, an external side opposite the internal side, and a female trough extending outwardly and vertically from middle of a lower portion of the external side, the female trough having a cylindrical shape;
• a forearm cuff comprising a base and a sleeve formed within the base and configured to secure a forearm of the person, the base having a cylindrical post configured to be placed into the female trough of the plate, the forearm cuff rotabably coupled to the plate via the post, wherein the forearm cuff is operable to rotate along the person's vertical axis of rotation and the post is configured to act as a pivot upon which the person rotates the forearm cuff, wherein the post is not fixed within the female trough, wherein the post is held in place when scapular stabilizing muscles of the person are contracted;
• wherein when the apparatus is secured to an elbow of an arm of the person, the forearm of the arm of the person forms a fixed angle between eighty-five degrees and ninety-five degrees with a humerus of the arm of the person, the torso of the person forming a fixed angle with the humerus, the angle being less than ninety degrees, and wherein movement of the person's arm is limited such that rotation of the forearm cuff follows a rotation of the person's humerus such that movement of the person's arm is limited to perform at least one of an internal rotation and an external rotation of the humerus.