OINAs Exam 1

Trapezius - Origin

Trapezius - Origin

Medial 1/3 superior nuchal line of occipital; external occipital protuberence (inion); ligamentum nuchae; spinous process of C7-T12 and supraspinous ligament

Trapezius - Insertion

Lateral 1/3 of posterior border of clavicle; medial margin of acromion process; superior lip of scapular spine; base of scapular spine

Trapezius - Nerve Innervation

Accessory (CN XI) motor / C3-C4 sensory

Trapezius - Action

Scapular elevation (superior fibers); retraction/adduction (middle fibers); depression (inferior fibers); superior (upward) rotation of the scapula (superior & inferior fibers)

Latissimus Dorsi - Origin

Spinous processes of lower 6 thoracic vertebrae (T7-T12); supraspinous ligament; spinous processes of lumbar & sacral vertabrae through thoracolumbar fascia; external lip of iliac crest (lower 3-4 ribs by fleshy attachments)

Latissimus Dorsi - Insertion

Floor of the intertubercular groove

Latissimus Dorsi - Nerve Innervation

thoracodorsal (C6-C7)

Latissimus Dorsi - Action

Arm extension, hyperextension, adduction and medial rotation. Most powerful action is drawing the arm down from above the head

Levator Scapulae - Origin

Transverse processes of vertebrae C1-C4

Levator Scapulae - Insertion

Posterior surface of medial border of scapula from superior angle to base of spine

Levator Scapulae - Nerve Innervation

Dorsal Scapular (C5); Cervical (C3-C4)

Levator Scapulae - Action

Elevates scapula; tilts glenoid cavity downward by rotating the scapula

Rhomboid Minor - Origin

Spinous processes of C7 & T1

Rhomboid Minor - Insertion

Medial border of scapula from base of spine to inferior angle

Rhomboid Minor - Nerve Innervation

Dorsal scapular (C5)

Rhomboid Minor - Action

Scapular elevation; retraction (adduction); downward rotation, fix scapula to thoracic wall

Rhomboid Major - Origin

Spinous processes of T2-T5; supraspinous ligament

Rhomboid Major - Insertion

Medial border of scapula from base of spine to inferior angle

Rhomboid Major - Nerve Innervation

Dorsal Scapular (C5)

Rhomboid Major - Action

Scapular elevation; retraction (adduction); downward rotation, fix scapula to thoracic wall

Deltoid - origin

lateral third of clavicle

anterior border

lateral border of acromion process

inferior lip of spine to smooth triangular space

deltoid - insertion

deltoid tuberosity of humerus

deltoid - nerve innervation

axillary (C5)

deltoid - action

can act as whole or

anterior: flexor and medial rotator

middle: chief abductor of humerus

posterior: extensor and lateral rotator of humerus

subscapularis - origin

subscapular fossa (medial 2/3)

subscapularis - insertion

lesser tuberosity of humerus

subscapularis - nerve innervation

upper and lower subscapular (C5-C6)

subscapularis - action

medial rotation and adduction of arm

holds head of humerus in glenoid cavity

supraspinatus - origin

medial 2/3 of supraspinous fossa

supraspinatus - insertion

superior facet of greater tuberosity of humerus

supraspinatus - nerve innervation

suprascapular (C5)

supraspinatus - action

arm abduction

holds heads of humerus in glenoid cavity

infraspinatus - origin

medial 2/3 of infraspinous fossa

infraspinatus - insertion

middle facet of greater tuberosity of humerus

infraspinatus - nerve innervation

suprascapular (C5)

infraspinatus - action

external (lateral) rotation of humerus

holds head of humerus in glenoid cavity

teres major - origin

dorsal surface of scapula near inferior angle

teres major - insertion

medial lip of inter tubercular sulcus of humerus (crest of lesser tubercle)

teres major - nerve innervation

lower subscapular (C5,C6)

teres major - action

adduction and internal (medial) rotation of humerus

important stabilizer of proximal end of humerus during adduction

teres minor - origin

upper 2/3 lateral border of scapula

teres minor - insertion

inferior facet of greater tuberosity of humerus

teres minor - nerve innervation

axillary (C5)

teres minor - action

external rotation of humerus

adduction/extension of humerus

holds humerus in glenoid cavity

pectoralis major - origin

anterior surface

medial half of clavicle

costal cartilage of upper 6 ribs

aponeurosis of external oblique muscle

pectoralis major - insertion

lateral lip of intertubercular groove (crest of greater tuberosity of humerus)

pectoralis major - nerve innervation

lateral pectoralis (C6)

medial pectoralis (C7,C8)

pectoralis major - action

adduction and medial rotation of arm

horizontal adduction

flexion (clavicular head)

extension (sternal head)

pulls trunk up with arms stabilized

pectoralis minor - origin

anterior surface and upper margin of ribs 3-5

pectoralis minor - insertion

medial border of coracoid process of scapula

pectoralis minor - nerve innervation

medial pectoral (C8)

pectoralis minor - action

scapular abduction

depresses tip of shoulder joint (downward and forward)

subclavius - origin

costal cartilage of rib 1

subclavius - insertion

inferior surface of clavicle (subclavian groove)

subclavius - nerve innervation

nerve to the subclavius (C5)

subclavius - action

depresses clavicle (lateral end)

assists in scapular depression and abduction

serratus anterior - origin

outer surfaces and superior border of ribs 1-8

midway between angles and costal cartilages (lower 3 digitations interdigitate with origin of external oblique muscles)

serratus anterior - inserition

anterior surface of entire medial border of scapula

serratus anterior - nerve innervation

long thoracic (C6-C7)

serratus anterior - action

protraction and rotation of scapula

fixes scapula for other muscles (anchor)

biceps brachii - origin

long head: supraglenoid tubercle of scapula

short head: tip of coracoid process

biceps brachii - insertion

radial tuberosity and bicipital aponeurosis

biceps brachii - nerve innervation

musculocutaneous (C6)

biceps brachii - action

flexion of arm, internal rotation and adduction, forearm flexion and supination

coracobrachialis - origin

tip of coracoid process

coracobrachialis - insertion

middle half of medial surface of humerus

coracobrachialis - nerve innervation

musculocutaneous (C6)

coracobrachialis - action

flexion of arm, internal rotation and adduction

brachialis - origin

distal half of anterior, medial and lateral surface of humerus, medial and lateral inter muscular septum

brachialis - insertion

ulnar tuberosity

brachialis - nerve innervation

musculocutaneous (C6)

brachialis - action

forearm flexion

triceps brachii - origin

long head - infraglenoid tubercle of scapula

lateral head: proximal 1/3 of posterior humerus

medial head: distal 2/3 of posterior humerus and medial IM septum

triceps brachii - insertion

upper surface of posterior part of olecranon process of ulna

triceps brachii - nerve innervation

radial nerve (C7-C8)

triceps brachii - action

extension and hyperextension of arm

elbow extension

(arm adduction by long head)

anconeus - origin

posterior surface of lateral epicondyle of humerus

anconeus - insertion

lateral side of olecranon process and upper posterior surface of ulna

aconeus - nerve innervation

radial (C7-C8)

aconeus - action

forearm extension

pronator teres - origin

humeral head: medial supracondylar ridge of humerus and medial epicondyle of humerus via common flexor tendon ulnar head: medial margin of coronoid process of ulna

pronator teres - insertion

middle of lateral side of shaft of radius

pronator teres - nerve innervation

median (C7)

pronator teres - action

forearm pronation and flexion of elbow

flexor carpi radialis - origin

medial epicondyle of humerus by common flexor tendon (CFT)

flexor carpi radialis - insertion

base of 2nd and 3rd metacarpal

flexor carpi radialis - nerve innervation

median (C7)

flexor carpi radialis - action

forearm pronation, elbow flexion wrist flexion and abduction (radial deviation)

palmaris longus - origin

medial epicondyle of humerus by common flexor tendon (CFT)

palmaris longus - insertion

palmar aponeurosis

palmaris longus - nerve innervation

median (C7-8)

palmaris longus - action

forearm pronation, wrist flexion tenses palmar fascia

flexor carpi ulnaris - origin

humeral head: medial epicondyle of humerus via common flexor tendon (CFT) ulnar head: medial border of olecranon process and posterior border of ulna (upper 2/3) by common aponeurosis

flexor carpi ulnaris - insertion

pisiform bone and hook of hamate (by pisohamate ligt) and base of 5th metacarpal (by pisometacarpal ligt)

flexor carpi ulnaris - nerve innervation

ulnar (C8)

flexor carpi ulnaris - action

forearm flexion and wrist flexion adduction (ulnar deviation)

flexor digitorum superficialis - origin

humeral head: medial epicondyle by common flexor tendon (CFT) ulnar head: medial surface of coronoid process of ulna radial head: upper half of anterior border of radius

flexor digitorum superficialis - insertion

palmar aspect, sides of shafts, middle phalanges of fingers 2 to 5 by split tendon

flexor digitorum superficialis - nerve innervation

median (C8)

flexor digitorum superficialis - action

forearm flexion, wrist flexion finger flexion at MPs and proximal IPs