Anatomy Chapter 18

  1. Origin- Sternal ends of the 3rd, 4th, and 5th ribs
    Insertion- Coracoid process of the scapula
    Action- Pulls scapula forward and downward
    pectoralis minor
  2. Origin- External surfaces of lateral parts of ribs 1 - 8/9
    Insertion- Anterior vertebral border of the scapula
    Action- Pulls scapula forward and downward
    serratus anterior
  3. Origin- Posterior tubercles of transverse process of C1-C4
    Insertion- Superior part of vertebral border of scapula
    Action- Elevates scapula and tilts its glenoid cavity inferiorly by rotating scapula
    levator scapulae
  4. Origin- Spinous process of T2-T5
    Insertion- Vertebral border of the scapula from the inferior border of the rhomboideus minor to the inferior angle of the scapula
    Action- Adducts scapula and rotates it to depress glenoid cavity
    rhomboideus major
  5. Origin- Medial 1/3 of superior nuchal line, external occipital protuberance, nuchal ligament, and spines of C7 and all thoracic vertebrae
    Insertion- Lateral third of clavicle, acromion process, and spine of scapula
    Action- Elevates, retracts, and rotates scapula; superior fibers elevate; middle fibers retracts; inferior fibers depress scapula; superior and inferior fibers work together in superior rotation of scapula
  6. Origin- Spines of sacral, lumbar, and lower thoracic vertebrae; iliac crest and lower 4 ribs
    Insertion- intertubercular groove of the humerus
    Action- extends, adducts, and rotates humerus medially; retracts shoulder
    latissimus dorsi
  7. Origin- Clavicular Head: anterior surface of medial half of clavicle. Sternocostal Head: anterior surface of sternum, superior six costal cartilages and aponeurosis of external abdoninal oblique
    Insertion- Crest of greater tubercle
    Action- Adducts and medially rotates humerus; draws shoulder joint anteriorly and inferiorly
    pectoralis major
  8. Origin- Clavicle, acromion process, spine of the scapula
    Insertion- Deltoid tuberosity of the humerus
    Action- Anterior Part: Flexes and medially rotates arm. Middle Part: Abducts arm. Posterior Part: Extends and laterally rotates arm
  9. Origin- Coracoid process of the scapula
    Insertion- Middle third of medial surface of humerus
    Action- Flexes and adducts arm at shoulder joint
  10. Origin- Inferior angle and lateral border of scapula
    Insertion- Crest of lesser tubercle of the humerus
    Action- Medially rotates and adducts arm
    teres major
  11. Origin- Subscapular fossa
    Insertion- Lesser tubercle of humerus
    Action- Extends humerus, adducts and rotates arm medially
  12. Origin- Supraspinous fossa of the scapula
    Insertion- Greater tubercle of the humerus
    Abducts and laterally rotates humerus
  13. Origin- Infraspinous fossa of the scapula
    Insertion- Greater tubercle of the humerus
    Action- Rotates arm laterally
  14. Origin- Superior part of axillary border of scapula
    Insertion- Greater tubercle of humerus
    Action- Rotates arm laterally
    teres minor
  15. List the four muscles that make up the rotator cuff.
    subscapularis, supra spinatous, infraspinatus, & teres minor
  16. What is hte main function of the rotator cuff?
    holds the head of the humerus in the glenoid cavity during movements of the shoulder joint
  17. What separates the limbs into compartments?
    deep fascia
  18. What two compartments occur in the brachium?
    anterior & posterior
  19. Origin- Short Head: Coracoid process of scapula. Long Head: Supraglenoid tubercle of scapula.
    Insertion- Radial tuberosity and fascia of forearm via bicipital aponeurosis
    Action- Flexes and supinates forearm
    biceps brachii
  20. Origin-Distal half of anterior shaft of the humerus
    Insertion- Coronoid process of ulna
    Action- Flexes forearm
  21. Origin-Proximal two thirds of lateral supracondylar ridge of humerus
    Insertion- Lateral surface of distal end of radius
    Action- Flexes forearm
  22. Origin- Long Head: Infraglenoid tubercle of scapula. Lateral Head: Posterior surface of humerus superior to radial nerve groove. Medial Head: Posterior surface of humerus inferior to radial nerve groove
    Insertion- Olecranon process of the ulna
    Action- Extends forearm; Long head steadies ehad of abducted humerus
    triceps brachii
  23. Origin- Medial epicondyle of the humerus and coronoid process of ulna
    Insertion- Middle of lateral surface of the radius
    Action- Pronates forearm
    pronator teres
  24. Origin- Distal fourth of anterior surface of ulna
    Insertion- Distal fourth of anterior surface of radius
    Action- Pronates hand
    pronator quadratus
  25. Origin- Lateral epicondyle of the humerus and crest of the ulna
    Insertion- Lateral surface of the proximal third of radius
    Action- Supinates forearm
  26. Origin- Medial epincondyle of the humerus; anterior, proximal ulna and radius; interosseous membrane
    Insertion- Carpals, metacarpals, and phalanges
    Action- Flex wrist and digits
  27. Origin- Lateral epicondyle of the humerus; posterior surfaces of the radius and ulna; interosseous membrane
    Insertion- Carpals, metacaroals, and phalanges
    Action- Extend wrist and digits
  28. What is another name for the flexor retinaculum of the wrist?
    carpal ligament
  29. The flexor retinaculum of the wrist and the arch of the carpals form what structure?
    carpal tunnel
  30. What group of muscles forms the thick, fleshy mass at the base of the thumb and work to abduct, flex or oppose the thumb?
    thenar group
  31. What group of muscles forms the small fleshy mass at the base of the fifth digit of the hand and work to abduct, flex, and oppose the 5th digit?
    hypothenar group
  32. Within the hand, what group of muslces lies between the 1st and 5th digits?
    midpalmar group
  33. Origin- Tendons of a flexor which sends a tendon to the distal phlanx of digits 2-5
    Insertion- Lateral sides of extensor expansions of digits 2-5
    Action- Flex digits at metacarpophalangeal joints and extend interphalangeal joints
    lumbrical muscles
  34. Origin- Adjacent sides of two metacarpal bones
    Insertion- Extensor expansions and bases of proximal phalanges of digits 2-4
    Action- Abducts digits 2-4
    dorsal interossei
  35. Origin- Palmar surfaces of metacarpals 2, 4, and 5
    Insertion- Extensor expansions of digits and bases of proximal phalanges of digits 2, 4, and 5
    Action- Adduct digits 2, 4, and 5
    palmar interossei
  36. What muscle flexes the elbow but neither originates nor inserts on the humerus?
    biceps brachii
  37. The tendons of what muscle group can be seen on the dorsum of the hand?
    extensor groove
  38. What muscle forms the anterior border of the axilla?
    pectoralis major
  39. What muscle lies in the infraspinous fossa?
  40. What muscle inserts on the olecranon process?
    triceps brachii
Card Set
Anatomy Chapter 18
Muscles, Part 2