PE 4 (Muscles) Flashcards
Frontalis
Action: Raises eyebrows
Temporalis
Action: Closes jaw
Occipitalis
Action: Pulls scalp posteriorly
Orbicularis Oculi
Action: Closes eye, blinking, squinting
Orbicularis Oris
Action: Closes lips
Trapezius*
Action: Stabilizes, raises, retracts, rotates scapula
Origin: Occipital bone, C7, Thoracic vertebrae
Insertion: Scapula, Clavicle
Masseter*
Action: Prime mover of jaw closure
Origin: Zygomatic bone
Insertion: Mandible
Zygomaticus (Major)
Action: Raises lateral corners of mouth (smiling)
Sternocleidomastoid*
Action: Flexes and laterally rotates the head
Origin: Manubrium (sternum) and clavicle
Insertion: Mastoid process of temporal bone, Occipital bone
Pectoralis Major*
Action: Prime mover of arm flexion
Origin: Sternal end of clavicle, sternum
Insertion: Greater tubercle of humerus
Pectoralis Minor*
Action: Draws scapula forward and down
Origin: Anterior surfaces of ribs
Insertion: Scapula
Latissimus Dorsi*
Action: Prime mover of arm extension
Origin: Thoracic vertebra, Ribs, Iliac crest, (inferior angle of) Scapula
Insertion: Humerus
Serratus anterior*
Action: Rotates scapula so inferior angle moves up
Origin: Ribs
Insertion: Vertebral border of scapula
Trapezius*
Action: Stabilizes, raises, retracts, rotates scapula
Origin: Occipital bone, C7, Thoracic vertebrae
Insertion: Scapula, Clavicle
Teres Major*
Action: Extends, medially rotates, adducts humerus
Origin: Inferior angle of scapula
Insertion: Lesser tubercle of humerus
Infraspinatus
Action: Rotates humerus laterally
Rhomboid Major
Action: Stabilizes scapula
Rectus abdominis*
Action: Flex and rotate lumbar vertebral column
Origin: Pubic crest
Insertion: Xiphoid process, Ribs
External oblique
Action: Flex vertebral column and compress abdominal wall
Deltoid*
Action: Prime mover of arm abduction
Origin: Clavicle, Acromiom, Spine of scapula
Insertion: Humerus