Human Anatomy Muscles Part 1

sternocleiodmastoid (action)
Flexes and laterally rotates the head
Scalenes (Ant, mid, post)
Elevate fist two ribs,
Aid in inspiration
Splenius capitis and cervicis
Extension/hyperextension of head
Erector spinae
(iliocostalis, Longissimus, spinalis)
trunk extension, rotation, and lateral flexion of vertebral column
(Thoracis, cervicis, capitis region)
Extends vertebral column
Quadratus lumborum (action)
Flexes vertebral column laterally, pelvic elevation
External intercostals (action)
Pulls ribs toward one another to elevate rib cage
Internal intercostals (action)
Draws ribs together and depress rib cage
Diaphragm (innervation)
Phernic n. C4
Diaphragm (action)
Prime mover of inspiration; flattens on contraction
External / Internal oblique (action)
Compresses abdominal contents

Trunk rotation and lateral flexion
Transversus abdominis (action)
Compresses abdominal contents
Rectus abdominis (action)
Flex and rotate lumbar region of vertebral column
Pectoralis major (action)
Prime mover of arm flexion;
rotates arm medially;
adducts arm
Pectoralis major (origin)
Sternal end of clavicle, sternum, cartilage of ribs 1-6, and aponeurosis of external oblique m.
Pectoralis major (insertion)
Fibers converge to insert by a short tendon into lateral side of the intertubercular sulcus of the humerus
Pectoralis major (innerveration)
Lateral and medial pectoral nn. C5-8, T1
Pectoralis minor (origin)
Anterior surface of ribs 3-5 (or 2-4)
Pectoralis minor (insertion)
Coracoid process of scapula
Pectoralis minor (innervation)
Medial and lateral pectoral nn. C6-8
Pectoralis minor (action)
With ribs fixed, draws scapula forward
Serratus anterior (origin)
muscle slips from ribs 1-8 or 9
Serratus anterior (insertion)
Entire anterior surface of vertebral border of scapula
Serratus anterior (innervation)
Long thoracic n. C5-7
Serratus anterior (action)
Rotates scapula so that its inferior angle moves laterally and upward
Scapular abduction
Trapezius I ( upper fibers) (Origin)
Occipital protruberance,
spinous processes C1-7
Trapezius I ( upper fibers) (Insertion)
Lateral 1/3 of clavicle and acromion of scapula
Trapezius I ( upper fibers) (Innervation)
Accessory n. C3-4
Trapezius I ( upper fibers) (Action)
Scapular elevation, scapular upward rotation
Trapezius II (middle fibers) (origin)
spinous processes C1-T5
Trapezius II (middle fibers) (insertion)
Medial margin of acromion process, superior spine of scapula
Trapezius II (middle fibers) (innervation)
Accessory n. ,C3-4
Trapezius II (middle fibers) (action)
Scapular adduction
Trapezius III (lower fibers) (origin)
spinous processes T6-12
Trapezius III (lower fibers) (insertion)
Medial spine of scapula and tubercle at apex of spine of scapula
Trapezius III (lower fibers) (innervation)
Accessory n. C3-4
Trapezius III (lower fibers) (action)
Scapular depression, and upward rotation
Levator scapulae (origin)
Transverses processes of C1-4
Levator scapulae (insertion)
Medial border of scapula, superior to the spine
(superior angle of scapula)
Levator scapulae (innervation)
dorsal scapular n. C4-5
Levator scapulae (action)
Elevates /adducts scapula
Rhomboid major (origin)
spinous processes of T2-5
Rhomboid major (insertion)
Medial border of scapula
Rhomboid major (Innervation)
Dorsal scapular n. C4-5
Rhomboid major (action)
scapula adduction and downward rotation
Rhomboid minor (origin)
Ligamentum nuchae and Spinous processes C7- T1
Rhomboid minor (insertion)
Medial border of scapula
Rhomboid minor (innervation)
Dorsal scapular n. C4-5
Rhomboid minor (action)
Stabilize and addicts scapula
Latissimus dorsi (origin)
Spinous processes of T7 -T12, thoracolumbar fascia, iliac crest, and inferior 3 or 4 ribs
Latissimus dorsi (insertion)
intertubercular sulcus of humerus
Latissimus dorsi (innervation)
Thoracodorsal n. C6-8
Latissimus dorsi (action)
Prime mover of arm extension; adduction and medial rotation at shoulder