1. Sternocleidomastoid
    • Two-headed muscle located deep to platysma on anterolateral surface of neck
    • O-manubrium of sternum and medial portion of clavicle
    • I-mastoid process of temporal bone and superior nuchal line of occiptial bone
    • Action - Flexes and laterally rotates the head
  2. Erector Spinae
    • Action - Prime move of back extension
    • Three column: iliocostalis, logissimus, and spinalis muscles
  3. Rectus abdominis
    • Medial muscle pair; extend from pubis to rib cage; ensheathed by aponeuroses of lateral muscles; segmented by three tendinous intersections
    • O-pubic crest and symphysis
    • I-xiphoid process and costal cartilages of ribs
    • A-Flex and rotate lumbar region of vertebral column
  4. Pectoralis minor
    • Flate, thin muscle directly beneath and obscured by pectoralis major
    • O-anterior surfaces of ribes 3-5
    • I-coracoid process of scapula
    • A-With ribs fixed, draws scapula forward and downward
  5. Serratus anterior
    • Fan-shaped muscle; lies deep to scapula, deep and inferior to pectoral muscles on later rib cage
    • O-by series of muscle slips from ribs 1-8
    • I-entire anterior surface of vertebral borders scapula
    • A-Rotates scapula so that its inferior angle moves laterally and upward
  6. Subclavius
    • Small cylindrical muscle extending from rib 1 to clavicle
    • O-costal cartilage of rib 1
    • I-groove on inferior surface of clavicle
    • A-Help stablize and depress pectoral girdle
  7. Trapezius
    • Most superficial muscle of posterior thorax; flat and triangular
    • O-occipital bone, ligamentum nuchae, and spines of C7 and all thoracic vertebrae
    • I-a continuos insertion along acromion and spine of scapula and lateral third of clavicle
    • A-Stabilizes, raises, retracts, and rotates scapula
  8. Levator scapulae
    • Located at back and side of neck, deep to trapezius; thick, traplike muscle
    • O-transverse processes of C-1-C4
    • I-medial border of the scapula, superior to the spine
    • A-Elevates/adducts scapula
  9. Rhomboids
    • Two rectangular muscles lying deep to trapezius and inferior to levator scapulae; rhomboid minor is the more superior muscle
    • O-Spinous processes of C7 and T1 and spinjous processes of T2-T7
    • I-medial border of scapula
    • A-Stabilize scapula
  10. Pectoralis major
    • Large, fan shaped muscle covering upper porrtion of chest
    • O-Sternal end of clavicle, sternum, cartilage of ribs
    • I-fibers converge to insert by a short tendon into greater tubercle of humerus
    • A-Prime mover of arm flexion; rotates arm medially; adducts arm
  11. Deltoid
    • Thick, multipennate muscl forming rounded shoulder muscle mass
    • O-embraces inserstion of the trapezius; lateral third of clavicle; acromion and spine of scapula
    • I-deltoid tuberosity of humerus
    • A-Prime mover of arm abduction when all its fiber contract simultaneously
  12. Latissimus dorsi
    • Broad, flat, triangular muscle of lower back (lumbar region)
    • O-indirect attachment via thoracolumbar fascia into spines of lower six thoracic vertebrae, lumbar vertebrae, lower 3 to 4 ribs and iliac crest
    • I-spirals around teres major in insert in floor of intertubercular sulcus of humerus
    • A-Prime movers of arm extension; adduction and medial rotation at shoulder
  13. Teres major
    • thick, rounded muscle; located inferior to teres minor;
    • O-posterior surface of scapula at inferior angle
    • I-crest of lesser tubercle on anterior humerus; insertion tendon fused with that of latissimus dorsi
    • A-Extends, medially rotates, and adducts humerus
  14. Coracobrachialis
    • Small, cylindrical muscle
    • O-coracoid process of scapula
    • I-medial surface of humerus shaft
    • A-Flexion and adduction of the humerus
  15. Subscapularis
    • Forms part of posterior wall of axilla
    • O-subscapular fossa of scapula
    • I-lesser tubercle of humerus
    • A-Chief meidal rotator of humerus
  16. Supraspinatus
    • Named for its location on posterior aspect of scapula
    • O-supraspinous fossa of scapula
    • I-superior part of greater tubercle of humerus
    • A-initiates abduction
  17. Infraspinatus
    • Partially coverd by deltoid and trapezius
    • O-infraspinous fossa of scapula
    • I-greater tubercle of humerus posterior to insertion of supraspinatus
    • A-Rotates humerus laterally
  18. Teres minor
    • small, elongated muscle; lies inferior to infraspinatus and may be inseparable from that muscle; a rotator cuff muscle
    • O-lateral border of dorsal scapular surface
    • I-greater tubercle of humerus inferior to infraspinatus insertion
  19. Triceps brachii
    • Large fleshy muscle; the only muscle of posterior eompartment of arm
    • O-long head; infraglenoid tubercle of scapula
    • I-by common tendon into olecranon process of ulna
    • A-Powerful forearm extensor
  20. Biceps brachii
    • Two headed fusiform muscle; bellies unite as insertion point is approached
    • O-short head; coracoid process; long head: supraglenoid tubercle and lip of glenoid cavity
    • I-by common tendon into radial tuberosity
    • A-Flexes elbow joint and supinates forearm
  21. Brachialis
    • Strong muscle that is immediately deep to beceps brachii on distal humerus
    • O-front of distal humerus
    • I-coronoid process of ulna and capsule of elbow joint
    • A-A major forearm flexor
  22. Pronator teres
    • Two-headed muscle; seen in superficial view between proximal margins of brachioradialis and flexor carpi radialis
    • O-medial epicondyle of humerus; coronoid process of ulna
    • I-by common tendon into lateral radius, midshaft
    • A-Pronates forearm
  23. Flexor carpi radialis
    • Runs diagonally across forearm;
    • O-medial epicondyle of humerus
    • I-base of second and third metacarpals
    • A-Powerful flexor of wrist
  24. Palmaris longus
    • Small fleshy muscle with a long insertion tendon
    • O-medial epicondyle of humerus
    • I-fascia of palm (palmar aponeurosis)
    • A-Tenses skin and fascia of palm during hand movements
  25. Flexor carpi ulnaris
    • Most medial muscle of this group; two headed
    • O-medial epicondyle of humerus; olecranon process an dposterior surface of ulna
    • I-pisiform and hamate bones and base of fifth metacarpal
    • A-Powerful flexor of wrist; also adducts hand
  26. flexor digitorum
    • two head muscle; more deeply placed
    • O-medial epicondlye of humerus, coronoid process of ulna
    • I-by four tendons into middle phalanges of fingers 2-5
    • A-Flexes wrist and middle phalanges of fingers 2-5
Card Set
Description of muscles