Head
Closes the Eyelid
orbicularis oculi
Laterally rotates arm, works with infraspinatus
Teres Minor
Tenses skin of neck
platysma
prime mover of inspiration
diaphragm
What is the action of the serratus anterior
Rotates scapula upward. Holds scapula to chest wall
Moves the lips, used for kissing
Orbicularis oris
Prime mover of arm abduction when muscles contract simultaneously.
Deltoid
extends the head
splenius
Draws ribs together and depress rib cage
Internal intercostals
Insertion: central Tendon
Diaphragm
Elevates the mandible
Masseter
Prime mover of arm flexion, rotates arm medially, and adducts arm
Pectoralis Major
Flexes the cervical spine
sternocleidomastoid
flexes and laterally rotates lumbar of vertebral column.
Also stabilizes pelvis.
Rectus abdominus
Origin: lateral third of clavicle, acromion and spine of scapula.
Insertion: deltoid tuberosity of humerus
Deltoid
Origin: Zygomatic arch and zygomatic bone.
Insertion: angle and ramus of mandible
Masseter
Origin: posterior surface of scapula, at inferior angle
Insertion: crest of lesser tubercle on the anterior humerus
Teres Major
Stabilizes scapula
Rhomboids
What is the action of the external oblique
flexes vertebral column and compresses abdominal wall. Aides in trunk rotation and lateral flexion
What is the action of the subscapularis
Medially rotates arm (assisting pectoralis major)
Origin: Epicranial Aponeurosis
Insertion: skin of eyebrows and root of nose
Frontalis
Origin: coracoid process of scapula
Insertion: medial surface of humerus shaft
Coracobrachialis
Origin: Occipital bone, ligamentum nuchae and spines of C7 and all thoracic vertebrae.
Insertion: continuous insertion on acromion and spine of scapula
Trapezius
origin: fleshy strips from outer surfaces of lower 8 ribs.
Insertion: mostly into the linea alba, some into the pubic crest, and iliac crest.
External Oblique
Origin: by a series of muscle slips from ribs 1-8
Insertion: entire anterior surface of vertebral(medial) border of scapula.
Serratus anterior