Kines 262 Posterior Muscles

Scapular and Humerus Muscles

Scapular and Humerus Muscles

Orange Section

Upper Trapezius

Upper Trapezius Action

elevation of scapula

upward rotation of scapula

Upper Trapezius Origin

base of skull to occipital protuberance (inion)

Upper Trapezius Insertion

posterior lateral 1/3 of clavicle

Upper Trapezius Innervation

CN XI (accessory)

C3-C4 spinal nerves

Red Section

Middle Trapezius

Middle Trapezius Action

elevation of scapula

retraction of scapula

upward rotation of scapula

Middle Trapezius Origin

spinous processes of C7-T3

Middle Trapezius Insertion

medial border of the acromion process and superior border of the scapular spine

Middle Trapezius Innervation

CN XI (accessory)

C3-C4 spinal nerves

Dark Red Section

Lower Trapezius

Lower Trapezius Action

retraction of scapula

depression of scapula

upward rotation of the scapula

Lower Trapezius Origin

spinous process of T4-T12 thoracic vertebrae

Lower Trapezius Insertion

triangular space at the base of the scapular spine

Lower Trapezius Innervation

CN XI

C3-C4 spinal nerves

Rhomboid Minor

Rhomboid Minor Action

downward rotation

retraction of the scapula

Rhomboid Minor Origin

spinous processes of C7-T1

Rhomboid Minor Insertion

medial border of scapula (below the spine of scapula)

Rhomboid Minor Innervation

Dorsal Scapular Nerve (C5)

Rhomboid Major

Rhomboid Major Action

downward rotation

retraction of scapula

Rhomboid Major Origin

spinous processes of T2-T5

Rhomboid Major Insertion

medial border of scapula (below the spine of scapula)

Rhomboid Major Innervation

Dorsal Scapular Nerve (C5)

Serratus Anterior

Serratus Anterior Action

protraction of scapula

upward rotation of scapula

Serratus Anterior Origin

upper 8 or 9 ribs

Serratus Anterior Insertion

medial border of scapula

Serratus Anterior Innervation

Long Thoracic Nerve (C5-C7)

Levator Scapulae

Levator Scapulae Action

elevation of the scapula

Levator Scapulae Origin

transverse processes of C1-C4

Levator Scapulae Insertion

medial border of scapula

Levator Scapulae Innervation

Dorsal Scapular Nerve (C5)

C3-C4 spinal nerves

Teres Major

Teres Major Action

extension of scapula

internal rotation of the humerus

Teres Major Origin

inferior angle of scapula

Teres Major Insertion

medial lip of bicipital groove of humerus

Teres Major Innervation

Lower subscapular nerve (C5-C6)

Teres Minor

Teres Minor Action

external rotation

adduction of the humerus

Teres Minor Origin

lateral border of scapula

Teres Minor Insertion

greater tubercle of humerus

Teres Minor Innervation

Axillary Nerve (C5)

Infraspinatus

Infraspinatus Action

external rotation of humerus

Infraspinatus Origin

infraspinous fossa of scapula

Infraspinatus Insertion

greater tubercle of humerus

Infraspinatus Innervation

Suprascapular nerve (C5-C6)

Green Section

Supraspinatus

Supraspinatus Action

abduction of humerus

Supraspinatus Origin

supraspinous fossa of scapula

Supraspinatus Insertion

greater tubercle of humerus

Supraspinatus Innervation

Suprascapular nerve (C5)

Subscapularis

Subscapularis Action

internal rotation of humerus

Subscapularis Origin

subscapular fossa of scapula

Subscapularis Insertion

lesser tubercle of humerus

Subscapularis Innervation

Subscapular nerve (C5-C6)

Posterior Deltoid

Posterior Deltoid Action

extension of humerus

external rotation of humerus

abduction of humerus

Posterior Deltoid Origin

inferior edge of spine of scapula

Posterior Deltoid Insertion

deltoid tuberosity of humerus

Posterior Deltoid Innervation

Axillary nerve (C5-C6)

Latissimus dorsi

Latissimus dorsi Action

extension of humerus

adduction of humerus

internal rotation of humerus

Latissimus dorsi Origin

thoracolumbar fascia and spinous process of the lumbar spine and lower 6 thoracic vertebrae

Latissimus dorsi Insertion

floor of bicipital groove of humerus

Latissimus dorsi Innervation

Thoracodorsal nerve (C6-C8)

Brachium

Brachium

Triceps Brachii (long head)

Triceps Brachii (long head) Action

extension of elbow

extension of shoulder

adduction of shoulder

Triceps Brachii (long head) Origin

infraglenoid tubercle of scapula

Triceps Brachii (long head) Insertion

olecranon process of ulna

Triceps Brachii (long head) Innervation

Radial Nerve (C6-C8)

Triceps Brachii (lateral head)

Triceps Brachii (lateral head) Action

extension of elbow

Triceps Brachii (lateral head) Origin

Supero-lateral surface of humerus

Triceps Brachii (lateral head) Insertion\`

olecranon process of ulna

Triceps Brachii (lateral head) Innervation

Radial nerve (C6-C8)

Very Small Green Section

Triceps Brachii (medial head)

Triceps Brachii (medial head) Action

extension of elbow

Triceps Brachii (medial head) Origin

posterior surface of humerus, inferior to radial groove

Triceps Brachii (medial head) Insertion

olecranon process of ulna

Triceps Brachii (medial head) Innervation

Radial nerve (C6-C8)

Brachioradialis

Brachioradialis Action

flexion of elbow

pronation of forearm

supination of forearm

Brachioradialis Origin

lateral supracondylar ridge of humerus

Brachioradialis Insertion

styloid process of radius

Brachioradialis Innervation

Radial nerve (C6-C8)

Antebrachium & Hand

Extensor Carpi Ulnaris

Extensor Carpi Ulnaris Action

extension and adduction at wrist

weak extension of elbow

Extensor Carpi Ulnaris Origin

lateral epicondyle of humerus and dorsal surface of ulna

Extensor Carpi Ulnaris Insertion

base of 5th metacarpal

Extensor Carpi Ulnaris Innervation

Deep radial nerve (C6-C8)

Extensor Carpi Radialis Brevis

Extensor Carpi Radialis Brevis Action

extension and abduction of wrist

weak elbow extension