muscles of the axial body

• supraspinatus

• infraspinatus

• teres minor

• subscapularis

rotator cuff muscles: SITS

origin- Pubis bones

insertion- costal cartilage, xiphoid process

function- compress abdomen, flexes trunk, and involved in breathing

Rectus abdominis

origin- lower ribs

insertion- linea alba, iliac crest

function- flexes vertebral column, tenses abdominal wall, rotates trunk and bends it laterally

External oblique

origin- iliac crest and lumbodorsal fascia

insertion- lower ribs, linea alba, and xiphoid

function- compresses abdomen, spine/trunk flexion, and spine rotation and lateral flexion

internal oblique

origin- iliac crest, Lumbar vertebrae, lower ribs

insertion- linea alba, pubis

function- flexes trunk, compresses abdomen

Transverse abdominis

• main muscle of respiration

• provides passageway for structures from thorax to abdomen

• 2 surface: thoracic and abdominal

diaphragm

origin- occipital bone of skull and vertebral spines

insertion- clavicle, spine, and acromion process of scapular

function- raises/lowers shoulders

Trapezius

origin- cervical/thoracic spinal processes

insertion- medial border of scapula

function- retracts, elevates, and rotates scapula

Rhomboid

origin- transverse process of cervical vertebra

insertion- medial scapula

function- elevates scapula

Levator scapula

origin- outer surface of ribs

insertion- ventral surface of scapula

function- moves scapula forward and downward, thrust shoulders when pushing forward

serratus anterior

origin- sternal end of upper ribs

insertion- corocoid process of scapula

function- moves scapula forward/backward, raises ribs in inhalation

Pectoralis minor

origin- clavicle, sternum, costal cartilages of upper ribs

insertion- greater tubercle of humerus

function- flex, adduct, and rotate arm medially

Pectoralis major

origin- lateral scapula

insertion- intertubercular groove of humerus

function- extend, adduct, and rotate arm medially

Teres major

origin- clavicle, acromion, and spine of scapula

insertion- deltoid Tuberosity

function- flex, extend, and abduct arm

Deltoid

origin- thoracic/Lumbar spine, ribs 8-12

insertion- intertubercular groove of humerus

function- extend, adduct, and rotate arm medially

latissimus dorsi

origin- anterior scapula

insertion- lesser tubercle of humerus

function- rotate arm medially

subscapularis

origin- lateral scapula

insertion- greater tubercle of humerus

function- rotates arm laterally

Teres minor

origin- inferior posterior surface below spine of scapula

insertion- greater tubercle of humerus

function- rotate arm laterally

Infraspinatus

origin- superior scapula above spine

insertion- greater tubercle of humerus

function- abduct arm

supraspinatus