superficial muscles locations & functions

Buccinator

principal muscle of cheek essential for keeping food in cheek & b/w teeth

• also movement like whistling, blowing, sucking

• ex. playing a wind instrument

Masseter

elevates, protrude & retracts the mandible — essential for mastication (CHEWING)

Temporalis

responsible for moving the mandible (w/ masseter), clenching the jaw, & side-to-side chewing

muscles for mastication

only need to know 3 superficial ones

1. Masseter

2. Temporalis

3. Buccinator

(Lateral pterygoid & Medial pterygoid)

frontalis

forehead muscle responsible for raising the eyebrows & wrinkling the forehead

Nasalis

covers bridge & sides of the nose, responsible for furrow/opening/flaring the nostrils

Orbicularis Oculi

muscle encircling the eye; responsible for open (uncontracts) & closing (contracts) eyelids; includes blinking

Orbicularis Oris

muscle encircling the mouth; responsible for allowing lips to pucker (ex. whistling, kissing)

Levator Labii Superioris

lifts upper lip; for expressions such as sadness, distain, snarling; AKA Elvis muscle

Trapezius

diamond-shaped upper back and neck muscle; responsible for posture, neck, & arm movement; stabilizes the shoulder blades (w/ scapula)

Depressor Labii Inferioris

pulls lower lip down & slightly out for expressions of sadness, doubt, or bare the lower teeth when smiling

Depressor Anguli Oris

pulls corners of mouth downward & slightly sideways

Mentalis

chin muscle elevates and protrudes lower lip for expressions like pouting & chin wrinkling

Platysma

broad, thin muscle from neck to shoulder/collarbone area; depresses lower lip for frowning & mandible

Zygomaticus muscles

muscles that lift the corners of moth upwards for smiling; creates expressions like happiness & joy

Occipitalis Aponeurosis (aka Galea Aponeurotica or Epicranial Aponeurosis)

broad, fibrous sheet of muscle covering scalp responsible for scalp mobility; connects occipitalis to frontalis muscle —> occipitofrontalis muscle

Deltoid

triangular muscle on rounded contour of the shoulder; responsible for arm movement & stabilizing the shoulder joint

Pectoralis major

large, fan-shaped muscle in upper chest

Adductors

located on inner thigh responsible for pulling leg towards midline of body for hip stability & balance

Quadriceps

group of 4 muscles on anterior of thigh responsible for activities like walking, running, & jumping:

1. Rectus Femoris

2. Vastus Lateralis

3. Vastus Medialis

4. Vastus Intermedius (don’t need to know b/c deep muscle)

biceps brachii

2-headed muscle on anterior of humerus

Gastrocnemius

two-headed back of lower leg muscle; flexes the knee (bending the leg) & ankle for walking, running, & jumping

External Obliques

muscles on side of trunk essential for stabilization, posture, & flexing

Rectus abdominis

long, vertical muscles on front of abdomen; flexes trunk & stabilizes core

Gluteus maximus

largest & most powerful muscle in human body; crucial for hip stability/extension (moving leg back), lateral rotation, & upright posture

Triceps brachii

3-headed (long, lateral, medial) muscle on back of upper arm; responsible for elbow extension (straightening of arm), shoulder extension, & pushing motion

Latissimus dorsi

broad, triangular muscles covering the lower back that extends from lumbar to upper humerus; responsible for extending, adducting, & rotating for movements like swimming & rowing

Hamstrings

group of 3 muscles (semimembranosus, semitendinosus, biceps femoris) located on back of the thigh; stabilizes hip & knee joints for walking, running, & jumping; prone to injury in athletes

Brachioradialis

forearm muscle essential for flexing the elbow

Sartorius

longest muscle in the body, running diagonally across the thigh; responsible for rotate thigh & crossing the legs

Vastus lateralis

largest muscle in the quadriceps group; crucial for extending knee joint & stability

Vastus medialis

muscle in the quadriceps group

Rectus femoris

muscle in the quadriceps group

Tensor fasciae latae

small muscle on outer hip & thigh

Wrist flexors

Tibialis anterior

Erector spinae

crucial for posture & spinal extension

Semitendinosus

part of hamstring group w/ biceps femoris & semimembranosus

Semimembranosus

part of hamstring group

Wrist extensors

Peroneus

Soleus

Sternocleidomastoid

side of neck muscle attached to sternum & clavicle; responsible to enable head & neck movement

Occipitalis

thin, paired muscle at the back of the head; part of occipitofrontalis muscle group; moves scalp backwards