Muscle Types
& Names
Muscles
• Muscles cause movement primarily @ the
joints
• Muscles can attach to the body in 3 ways:
-directly to the bone
-by tendons (cords of connective tissue)
-by an aponeurosis (sheet of connective tissue)
Types of Muscles
 Prime mover – muscle with the major
responsibility for a
certain movement
 Antagonist – muscle that opposes or
reverses a prime mover
Types of Muscles
 Synergist – muscle that aids a prime
mover in a movement and
helps prevent rotation
 Fixator – stabilizes the origin of a prime
mover
Naming of Skeletal Muscles
 Direction of muscle fibers
Example: rectus (straight)
 Relative size of the muscle
Example: maximus (largest)
Naming of Skeletal Muscles
 Location of the muscle
Example: many muscles are named
for bones (e.g., temporalis)
 Number of origins
Example: triceps (three heads)
Naming of Skeletal Muscles
 Location of the muscles origin and
insertion
Example: sterno (on the sternum)
 Shape of the muscle
Example: deltoid (triangular)
 Action of the muscle
Example: flexor and extensor (flexes or
extends a bone)
Muscles of
the Head
(Face/Neck)
Muscles of Facial Expression
• Frontalis:
Origin - cranial aponeurosis
Insertion - skin of eyebrows
Action - raises eyebrows
Muscles of Facial Expression
• Orbicularis oculi:
Origin - frontal bone & maxilla
Insertion - tissue around eyes
Action - blinks and closes eyes; squinting
*spincter muscle of eyelids*
Muscles of Facial Expression
• Zygomaticus
Origin - zygomatic bone
Insertion - skin & muscle @ corner of lips
Action - raises corner of mouth
(smiling muscle)
*extends diagonally from corner of mouth to
cheekbone*
Muscles of Facial Expression
• Orbicularis oris
Origin - mandible & maxilla
Insertion - skin & muscle around mouth
Action - closes mouth, purses and protrudes lips
(kissing muscle)
*encircles mouth; sphincter muscle of lips with
fiber that run in many different directions*
Muscles of mastication (chewing)
• Masseter
Origin - zygomatic arch of temporal bone
Insertion - mandible
Action - closes jaw & elevates mandible
*extends across jawbone*
Muscles of mastication (chewing)
• Temporalis
Origin - temporal bone
Insertion - mandible
Action - closes jaw & elevates mandible
*fan-shaped muscle over temporal bone*
Muscles of mastication (chewing)
• Buccinator:
Origin - maxilla and mandible near molars
Insertion - orbicularis oris
Action - compresses cheek (as in whistling &
sucking); holds food between teeth
during chewing
*principal muscle of cheek; runs horizontally,
deep to masseter*
Neck Muscles
• Sternocleidomastoid
Origin - sternum & clavicle
Insertion - mastoid process of temporal bone
Action - flexes neck forward; rotates head
*two-headed muscle located deep to platysma
on anterolateral surface of neck*
Neck Muscles
• Platysma
Origin - connective tissue covering
superior chest muscles
Insertion - tissue around the mouth
Action - depresses the mandible, pulls
corners of mouth inferiorly (frowning
muscle)
*thins, sheet-like superficial muscle, plays a
role in facial expression*
Head and Neck Muscles
The End!