Sports Medicine - Muscles of the Shoulder

Where does the pectoralis major originate?

Medial half of the clavicle, the sternum, the costal cartilages of the upper six ribs, and the aponeurosis of the external oblique muscle

Where does the pectoralis major insert?

Greater tubercle of the humerus

What are the actions of the pectoralis major?

Flexes, adducts, and medially rotates the arm

Where does the latissimus dorsi originate?

Spinous processes of the lower six thoracic and the lumbar vertebrae, the sacrum, and the posterior iliac crest – all via the lumbodorsal fascia

Where does the latissimus dorsi insert?

Medial margin of the intertubercular groove of the humerus

What are the actions of the latissimus dorsi?

Extends, adducts, and medially rotates the arm; pulls the shoulder downward

Where does the deltoid originate?

Lateral third of the clavicle, the acromion process, and the spine of the scapula

Where does the deltoid insert?

Deltoid tuberosity of the humerus

What are the actions of the deltoid?

Abducts the arm; anterior fibers flex and medially rotate the arm; posterior fibers extend and laterally rotate the arm

Where does the supraspinatus originate?

Supraspinatus fossa of the scapula

Where does the supraspinatus insert?

Greater tubercle of the humerus

What are the actions of the supraspinatus?

Abducts the arm; slight lateral rotation

Where does the infraspinatus originate?

Infraspinatus fossa of the scapula

Where does the infraspinatus insert?

Greater tubercle of the humerus (posterior to the supraspinatus)

What are the actions of the infraspinatus?

Laterally rotates the arm; slight adduction

Where does the subscapularis originate?

Subscapular fossa of the scapula

Where does the subscapularis insert?

Lesser tubercle of the humerus

What are the actions of the subscapularis?

Medially rotates the arm

Where does the teres minor originate?

Axillary border of the scapula

Where does the teres minor insert?

Greater tubercle of the humerus (posterior to the infraspinatus)

What are the actions of the teres minor?

Laterally rotates the arm

Where does the trapezius originate?

Occipital bone, the ligamentum nuchae, and the spinous processes of the seventh cervical and all the thoracic vertebrae

Where does the trapezius insert?

Lateral third of the clavicle, the acromion process, and the spine of the scapula

What are the actions of the trapezius?

Elevates (upper portion) or depresses (lower portion), rotates, adducts, and stabilizes the scapula

Where does the rhomboid major originate?

Spinous processes of the seventh cervical and first thoracic vertebrae

Where does the rhomboid major insert?

Vertebral border of the scapula, below the spine of the scapula

What are the actions of the rhomboid major?

Adduct, stabilize, and rotate the scapula, lowering its lateral angle

Where does the rhomboid minor originate?

Spinous processes of the second through the fifth thoracic vertebrae

Where does the rhomboid minor insert?

Vertebral border of the scapula, at the base of the spine of the scapula

What are the actions of the rhomboid minor?

Adduct, stabilize, and rotate the scapula, lowering its lateral angle

Where does the serratus anterior originate?

Outer surface of the first nine ribs

Where does the serratus anterior insert?

Entire length of the ventral surface of the vertebral border of the scapula

What are the actions of the serratus anterior?

Stabilizes, abducts, and rotates the scapula

What muscle is this?

Pectoralis Major

What muscle is this?

Latissimus dorsi

What muscle is this?

Deltoid

What muscle is this?

Supraspinatus

What muscle is this?

Infraspinatus

What muscle is this?

Subscapularis

What muscle is this?

Teres minor

What muscle is this?

Trapezius

What muscle is this?

Rhomboid major

What muscle is this?

Rhomboid minor

What muscle is this?

Serratus anterior