Human Anatomy

Latissmus Dorsi Origin

Inferior angle of scapula, last 6 thoracic vertebrae, last 3-4 ribs, thoracolumbar fascia, posterior iliac crest.

Latissimus Dorsi Insertion

intertubercular groove of humerus

latissmus dorsi action

extends, adducts, and medially rotates shoulder

latissmus dorsi nerve

Thoracodorsal nerve (C6-C8)

Trapezius Origin

external occipital protuberance, medial portion of superior nuchal line of the occiput, ligamentum nuchae and spinous processes of c7-T12.

Trapezius Insertion

lateral 1/3 of clavicle, acromion, spine of scapula

trapezius action upper fibers

Bilaterally: Extend the head and neck

Unilaterally: Laterally Flex the head and neck to the same side

Rotate the head and neck to the opposite side

Elevate and Upwardly rotate the scapula

trapezius middle fibers action

adduct and stabilize the scapula (ST joint)

trapezius lower fibers action

depress and upwardly rotate the scapula (ST joint)

trapezius nerve

spinal portion of cranial nerve xi (Accessory) and ventral ramus c2, 3,4.

rhomboid major action

adduct, elevate and downwardly rotation of scapular (s/t joint)

rhomboid major origin

spinous processes of T2-T5

rhomboid major insertion

medial border of scapula between spine and inferior angle

rhomboid major nerve

dorsal scapular nerve (C4-5)

rhomboid minor action

Adduct, elevate, and downwardly rotate the scapula

rhomboid minor origin

spinous processes of C7-T1

rhomboid minor insertion

Upper portion of medial border of the scapula, across from spine of the scapula

rhomboid minor nerve

dorsal scapular nerve (C4-5)

levator scapulae action

Unilaterally:

Elevate and Downwardly rotate the Scapula

Laterally Flex and Rotate the head and neck same side.

Bilaterally: Extend the head and neck

levator scapulae origin

transverse processes of C1-C4

levator scapulae insertion

Medial border of scapula between superior angle and superior portion of spine of scapula.

levator scapulae nerve

C3 to C4 and dorsal scapular nerve (C4, C5)

serratus posterior inferior action

depress ribs during exhalation

serratus posterior inferior origin

Spinous processes of T12-L3

serratus posterior inferior insertion

Posterior surface of ribs 9-12

serratus posterior inferior nerve

T9-T12

serratus posterior superior action

elevate ribs during inhalation

serratus posterior superior origin

Spinous processes of C7-T3

serratus posterior superior insertion

Posterior surface of ribs 2-5th

serratus posterior superior nerve

Intercostal nerves T1-T4

quadratus lumborum action

Unilaterally: Laterally tilt (elevate) the pelvis, laterally flex the vertebral column to the same side, Bilaterally: Fix the last rib during forced inhalation and exhalation. Assist to extend the vertebral column.

quadratus lumborum origin

posterior iliac crest

quadratus lumborum insertion

12th rib, transverse processes L1-4

quadratus lumborum nerve

lumbar plexus T12-L4

deltoid all fibers actions

Abduct the shoulder (glenohumeral joint)

deltoid anterior fibers actions

flexes arm, medially rotates arm, horizontally adduct the shoulder

deltoid posterior fibers actions

extend and laterally rotate, horizontally abduct the shoulder.

deltoid origin

lateral 1/3 of clavicle, acromion, spine of scapula

deltoid insertion

deltoid tuberosity of humerus

deltoid nerve

Axillary nerve (C5, C6)

serratus anterior action with origin fixed

abduct, upwardly rotate, depress scapula, hold medial border of scapula against rib cage

serratus anterior action with fixed scapula

may act to elevate the thorax during forced inhalation.

serratus anterior origin

upper ribs 1-9 ribs.

serratus anterior insertion

anterior surface of medial border of scapula

serratus anterior nerve

Long thoracic nerve (C5, C6, C7, C8)

Pectoralis major all fibers action

Adduct and Medially rotate the shoulder

assist to elevate the thorax during forced inhalation (with flexed arm).

pectoralis major upper fibs action

flex and horizontally adduct the shoulder

pectoralis major lower fibers action

extend shoulder

pectoralis major origin

medial half of clavicle, sternum, and costal cartilages of ribs 1-6

pectoralis major insertion

crest of greater tubercle of humerus

pectoralis major nerve upper fibers

Lateral pectoral C5, 6, 7

pectoralis major nerve lower fibers

Lateral and medial pectoral C6, 7, 8, T1

pectoralis minor action

Depress, abduct, and downwardly rotate the scapula

pectoralis minor action with scapula fixed

Assist to elevate the thorax during forced inhalation

pectoralis minor origin

ribs 3-5

pectoralis minor insertion

medial surface of coracoid process of the scapula.

pectoralis minor nerve

Medial pectoral w/ fibers from a communicating branch of the lateral pectoral (C8, T1)

artery appearance

thicker in size.

nerve appearance

thinner.

subscapularis nerve location

under the scapula

subscapularis artery location

over the scapula

suboccipitals (rectus posterior major/minor & oblique capitis superior) action

Rock and tilt the head back into extension

suboccipitals (rectus capitis posterior majpr & oblique capitis inferior) action

Rotate the head to the same side

suboccipitals (oblique capitis superior)

Laterally flex the head to the same side

suboccipitals origin

axis C2, Tubercle of the posterior arch of the atlas C1, Transverse process of the atlas C1, Spinous process of the axis C2.

Suboccipitals insertion

inferior & between the nuchal line of occiput. Transverse process of the atlas.

suboccipital nerve

suboccipital

Teres Major action

extend, adduct, and medially rotate the shoulder (glenohumeral joint).

teres major origin

inferior angle and lower 1/3 of lateral border of scapula

teres major nerve

Lower subscapular nerve (C5, C6, C7)

Splenius Capitis action

Unilaterally: rotation/laterally flex the head and neck same side.

Bilaterally: extension of head and neck

Splenius Capitis origin

Inferior 1/2 of ligamentum nuchae and spinous processes of C7-T4

Splenius Capitis insertion

mastoid process and lateral portion of superior nuchal line

splenius capitis nerve

cervical

Splenius Cervicis action

Unilaterally:

Rotate and laterally flex the head and neck to the same side

Bilaterally:

Extend the head and neck

Splenius Cervicis origin

Spinous processes of T3-T6

Splenius Cervicis insertion

transverse processes of C1-C3

splenius cervicis nerve

cervical

Infraspinatus action

laterally rotates arm, adduct the shoulder (glenohumeral joint). Stablize the head of the humerus in a glenoid cavity.

Infraspinatus origin

infraspinous fossa of scapula

Infraspinatus insertion

greater tubercle of humerus

infraspinatus nerve

Suprascapular nerve (C4, C5, C6)

Supraspinatus action

abducts the shoulder & stabilize the head of the humerus in a glenoid cavity.

Supraspinatus origin

supraspinous fossa of scapula

Supraspinatus insertion

greater tubercle of humerus

supraspinatus nerve

Suprascapular nerve (C4, C5, C6)

subscapularis action

Medially rotate the shoulder

Stabilize the head of humerus in glenoid cavity

subscapularis origin

subscapular fossa of scapula

Subscapularis insertion

lesser tubercle of humerus

Subscapularis nerve

upper and lower subscapular nerve C5, C6, C7.

teres minor action

laterally rotate adduct the shoulder, stabilize the head of the humerus in a glenoid cavity.

teres minor origin

upper 2/3 of lateral border of scapula

teres minor insertion

greater tubercle of humerus

teres minor nerve

Axillary nerve (C5, C6)

iliocostalis action

Unilaterally: Laterally flex vertebral column to the same side

Bilaterally: Extend the vertebral column

iliocostalis origin

Common tendon (lumborum)

Posterior surface of ribs 1-12 (thoracis and cervicis)

iliocostalis insertion

Transverse processes of lumbar vertebrae 1-3 and posterior surface of ribs 6-12 (Lumborum)

Posterior surface of ribs 1-6 (Thoracis)

Transverse processes of lower cervicals (Cervicis)

Iliocostalis nerve

spinal

longissimus action

Unilaterally: Laterally flex vertebral column to the same side

Bilaterally: Extend the vertebral column

Longissimus origin

Common tendon (thoracis)

Transverse processes of upper five thoracic vertebrae (cervicis and capitis)