Rutgers Functional Human Anatomy lec 19a (upper extremity musculature)

appendicular musculature

- stabilize pectoral and pelvic girdle

- moving upper & lower limbs

- absorbs shocks and jolts when you walk, run & jump

- aiding in strengthening joint area

muscles that position the pectoral girdle (origin & insertion)

originate on the axial skeleton and insert on the clavicle and scapula

muscles that move the arm (origin & insertion)

originate on pectoral girdle and thoracic cage and insert on humerus

muscles that move the forearm and hand (origin & insertion)

originate on pectoral girdle and humerus and insert on radius, ulna and/or carpals

extrinsic muscles of the hand and fingers (origin & insertion)

originate on humerus, radius, ulna and insert on metacarpals and phalanges

intrinsic muscles of the hand

originate on carpal and metacarpal bones and insert on phalange

action line/direction of pull

shoulder joint:

flexion/extension

adduction/abduction

medial/lateral rotation

spurt and shunt muscles

- flexors and extensors

spurt - muscles that inserts close to the joints (biceps brachii)

shunt - muscles that inserts far away from joint (brachioradialis)

agonist muscles

prime movers; perform an action

antagonist muscle

performs the opposite movement of the agonist

synergistic muscles

assist a agonist/primary mover

stabilizer muscles

stabilize joint so movement can occur at another joint

4 groups of muscles in pectoral girdle and upper limb

muscles that:

position pectoral girdle

move the arm

move forearm and hand

move hand and fingers

muscles that position pectoral girdle

trapezius

rhomboid

levator scapulae

pectoralis minor

serratus anterior

subclavius

trapezius

- originate skull, spinous processes

- insert clavicle & scapula

- elevate, retract, adduction, depress, rotate, extend neck

rhomboid

- originate ligamentum nuchae & sp T2-T5 (major)

- originate C7-T1 (minor)

- insert medial border of scapula from spine to inferior angle

- adduct, opposite-side rotation (major & minor)

levator scapulae

- originate transverse process of 1st 4 cervical processes

- insert medial border of scapula (superior angle)

- elevate

pectoral minor

- originate anterior superior margin fo ribs 2-5

- insert coracoid process of scapula

- protraction, rotate, elevate ribs

serratus anterior

- originate ribs 1-10

- insert anterior surface of scapula

- protract scapula, abduction, rotate scapula

Subclavius

- originate 1st rib

- insert clavicle

- protraction & depress shoulder

muscles that move the arm

deltoid

supraspinatus

infraspinatus

subscapularis

teres major/minor

coracobrachialis

pectorlis major

latissimus dorsi

triceps brachii

biceps brachii

deltoid

- originate clavicle & scapula

- insert deltoid tuberosity of humerus

- abduct, flexion, extension

- horizontal adduction

supraspinatus

- originate supraspinous fossa

- insert greater tubercle of humerus

- rotate humerus medial

- abduction

infraspinatus

- originate infraspinous fossa

- insert greater tubercle of humerus

- external rotation

Subscapularis

- originate sub-scapular fossa of scapula

- insert lesser tubercle of humerus

- internal rotation & adduction

teres major/minor

- originate inferior angle of scapula (major)

- originate lateral border of scapula (minor)

- insert inter-tubercle surface of humerus (major)

- insert at greater tubercles of humerus (minor)

- extension & internal rotation, adduction (major)

- external rotation (minor)

coracoidbrachialis

- originate coracoid process

- insert shaft of humerus

- flexion, horizontal adduction

pectoralis major

- originate ribs 2-6, body of sternum, inferior & medial portion of clavicle

- insert crest of greater tubercle of humerus & intertubercule sulcus

- flexion, adduction, medial rotation, horizontal adduction

Lattisimus Dorsi

- originate sp of inferior thoracic, lumbar vertebrae, ribs 8-12, thoracolumbar fascia

- insert floor of intertubercule surface of humerus

- extend, abduct, medial/internal rotation

triceps brachii (long-head)

- originate infraglenoid tubercle of scapula (long-head)

- insert olecranon of ulna (long-head)

- extend, adduct

biceps brachii

- originate from superglenoid tubercle of scapula (long- head)

- coracoid process (short-head)

- insert radial tuberosity

- flexion

rotator cuffs

supraspinatus, infraspinaturs, teres minor, subscapularis (SITS muscles)

- stabilizers for shoulder

- can tear an tendon attachments (mainly supraspinatus)

horizontal abductors (move arm at shoulder)

posterior deltoid

middle/lower trapezius

infraspinatus

supraspinatus

teres minor

rhomboid major

horiztonal adductos (move arm at shoulder)

anterior deltoid

pectoral major

coracobrachialis