Musculoskeletal 2 Human Anatomy

bones of pectoral girdle

clavicle, scapula, humerus

dermatomes

map of where our sensations are in limbs from spinal cord

thumb gets sensation from which spinal nerve?

C6 (cervical 6)

why are dermatomes important?

depending on sensation loss, can pinpoint which specific intervertebral disc was problem

posterior root

sensory input to spinal cord

anterior root

motor info

spinal nerve diagram

dermatomes use posterior root or anterior root

posterior root

posterior ramus

goes into muscles of back

anterior ramus

goes into our front + limbs

brachial plexus

roots, trunk, division, cords, branches

roots are from which vertebraes

C5-T1

types of branches

axillary, musculocutaneous, median, radial, ulnar

all the branch nerves are what kind of nerves

peripheral nerves

trapezius fibers

superior, middle, inferior

superior fibers action

elevate scapula

middle fibers action

adduct scapula

inferior fibers action

depress scapula

trapezius innervation

CN XI

levator scapulae action

elevates scapula

rhomboid action

elevates + adduct scapula

protraction in other words mean

abduction

retraction in other words mean

adduction

serratus anterior action

depress + abduct scapula

pectoralis minor action

depress + abduct scapula

subclavius action

depress clavicle

muscles on arm that comes from axial skeleton

pectoralis major + latissimus dorsi

pectoralis major action

flex, adduct, + medially rotate arm

pectoralis major innervation

pectoral nerves

latissimus dorsi action

extend, adduct, + medially rotate arm

latissimus dorsi innervation

thoracodorsal nerve

deltoid action

flex, abduct, extend, medially + laterally rotate arm

deltoid innervation

axillary nerve

coracobrachialis action

flexes + adducts arm

coracobrachialis innervation

musculocutaneous nerve

biceps brachii action

flexes + supinates forearm, flexes arm

biceps brachii innervation

musculocutaneous nerve

teres major action

extend, adduct, medially rotate arm

teres major innervation

subscapular nerve

triceps brachii medial + lateral head action

extend elbow

triceps brachii long head action

extends elbow, extends + adducts shoulder

triceps brachii innervation

radial nerve

rotator cuff muscles

supraspinatus, infraspinatus, teres minor, subscapularis

rotator cuff action

abduct, external rotation, external rotation, internal rotation

rotator cuff innervation

posterior branches of brachial plexus

why is anterior dislocation so common?

scapula covering shoulder, so cannot move as freely and get dislocated