Origin Insertion Action Nerve Supply Anterior surface of scapula Greater tubercle of humerus Abducts the arm Suprascapular nerve
-The supraspinatus is the muscle that runs along the top of the shoulder. -The distal supraspinatus tendon connects the supraspinatus to the upper arm bone, or humerus, and forms part of the rotator cuff, a group of muscles and tendons that support the shoulder. -The other three muscles whose connections to the arm constitute the rotator cuff are the subscapularis, which controls internal rotation; the teres minor, which controls external rotation; and the infraspinatus, which assists the arm in elevating during external rotation. -Supraspinatus muscle stabilizes the head of the arm bone in the shoulder joint preventing it from slipping upwards during shoulder movements.
Origin Insertion Action Nerve Supply Tubercle below glenoid cavity and lateral an medial surfaces of humerus Olecranon process of ulna Extends elbow Radial nerve
-They are named as triceps group of muscles, because it is not a single muscle. -These muscles make up over two thirds of your upper arm and work with the biceps muscles. -Triceps means three heads and that each of these heads (long, lateral and medial) performs a different function - -Anything that requires you to use straight arms generally means you are using your triceps. -The most common triceps injury is a pull or rupture, this can occur during overexertion in sports or weight lifting.
Origin Insertion Action Nerve Supply Acromion Process, spine of the scapula, the clavicle Deltoid tuberosity of humerus Abducts, extends, and flexes arm Axillary Nerve
-The deltoid is broken up into three parts the front deltoid, the side deltoid, and the posterior -Deltoids are one of the hardest muscles to develop while working out. -Constantly being involved in upper body movement the deltoid hardly gets and rest. -The name deltoid was originally called the Deltoideus. This name came about by the shape of the Greek letter Delta which is a triangle.