Muscles Flashcards
Latissimus dorsi
O: ribs, thoracic and lumbar vertebrae, ilium
I: humerus
Action: prime mover of arm extension (extends shoulder joint) adducts and medially rotates arm
Deltoid
O: clavicle, scapula
I: humerus
Action : prime mover of arm abduction, aids in flexion, extension and rotation of humerus
Frontalis
O: Cranial aponeurosis
I: Skin of the eyebrows and root of nose
Action: Raises eyebrows, wrinkles skin of forehead
Orbicularis oculi
O: frontal and maxillary bone
I: tissue of eyelids
Action: closes eyelids, produces blinking and squinting
Orbicularis oris
O:Maxillary bones and mandible
I: muscle and skin at lips
Action: Kissing muscle- purses lips, closes lips
Masseter
O:Zygomatic arch
I: mandible
Action: Closes jaw and elevates mandible
Sternocleidomastoid
O: Sternum and clavicle
I: Temporal bone
Action: Flexion of neck, rotation of head towards shoulders
Trapezius
O:Occipital bone, cervical and thoracic vert.
I: Scapula, clavicle
Action: extends neck, adducts scapula
External intercostal
O: Inferior border of each rib
I: Superior border of next rib
Action: Elevates ribs, inspiration
Internal intercostal
O:Superior border of each rib
I: inferior border of previous rib
Action: Depresses ribs for expiration
Diaphragm
O: Xiphoid process, ribs, lumbar vert.
I: Central tendinous sheet
Action: Expands thoracic cavity for inspitation, prime mover, compresses abdominopelvic cavity to aid in urination, deification, labor and delivery
Suprasinatus
O: Scapula
I: Humerus
Action: adducts arm and assists deltoid, helps stabilize shoulder joint
Infraspinatus
O: Scapula
I: Humerus
Action: lateral rotation of humerus, helps stabilize shoulder joint
Subscapularis
O:Scapula
I: Humerus
Action: medial rotation of humerus, helps stabilize shoulder joint
Tres minor
O: Scapula
I: humerus
Action: Lateral rotation of humerus, helps stabilize shoulder joint
