Frontalis (frontal belly)
A: draws scalp anteriorly, raises eyebrows, wrinkles skin of the forehead
Origin: Epicranial Aponeurosis
Occipitalis (occipital belly)
A: draws scalp posteriorly
I: Epicranial Aponeurosis
Obicularis Oculi
A: closes the eye
Obicularis Oris
A: closes and protrudes lips (kissing), compresses lips against teeth, shapes lips for speech
Buccinator
A: presses cheeks against teeth and lips (like for blowing, whistling, sucking, assists with chewing, draws corners of mouth laterally
Zygomatic Major
A: draws angles of mouth superiorly and laterally (smiling)
Risorius
A: draws angles of mouth laterally
Levator Labii Superioris
A: raises upper lip
Depressor Labii Inferioris
A: depresses/lower lower lip
Levator Anguli Oris
A: draws angle of mouth laterally and superiorly
Depressor Anguli Oris
A: draws angle of mouth laterally and inferiorly (like when opening mouth)
Mentalis
A: elevates and protrudes lower lip, pulls skin of chin up (pouting)
Platysma
A: draws outer part of lower lip inferiorly and posteriorly, depresses mandible
Masseter
A: elevates mandible (closes mouth)
Temporalis
A: elevates and retracts mandible
Superior Rectus
A: moves eye superiorly/elevates
Inferior Rectus
A: moves eye inferiorly/depresses
Lateral Rectus
A: moves eye laterally (abduction)
Medial Rectus
A: moves eye medially (adduction)
Superior Oblique
A: moves eye inferiorly and laterally, rotates them medially
Inferior Oblique
A: moves eye superiorly and medially, rotates them laterally
Sternocleidomastoid (SCM)
Action when acting together: flexes neck/cervical vertebral column, extends head at atlanto-occipital joint
Action unilaterally: lateral flexion of head and neck to same side, rotate head to opposite side, can elevate sternum during forced breathing
Splenius Capitus
A: extend head and vertebral column
Erector Spinae (group):
Spinalis Thoracis
Longissimus Thoracis
Iliocostalis Thoracis
A: All 3 extend the vertebral column at their respected regions
Digastric
A: elevates hyoid bone
Stylohyoid
A: elevates hyoid bone
Mylohyoid
A: elevates hyoid bone
Omohyoid
A: depresses hyoid bone
Semispinalis Capitis
Action when acting bilaterally: extend head and vertebral column
Action when acting unilaterally: rotate head to opposite side
Levator Scapulae
A: elevates scapula, rotates it downward
Pectoralis Minor
A: abducts scapula, rotates it downward
I: Coracoid Process of Scapula
Rhomboid Major
A: elevates and adducts the scapula, rotates it downward, stabilizes scapula
Rhomboid Minor
A: elevates and adducts the scapula, rotates it downward, stabilizes scapula
Serratus Anterior
A: stabilizes the scapula
known as the “BOXER’s MUSCLE”, useful with horizontal arm movements like punching and pushing
Trapezius
Action of superior portion: upward rotation of scapula
Action of middle fibers: adduct scapula
Action of inferior fibers: depress scapula
Coracobrachialis
A: flexes and adducts arm at the shoulder joint
O: corocoid process of the scapula
Pectoralis Major
A: adducts and medially rotates the arm
Teres Major
A: extends arm at the shoulder joint, medially rotates arm
Latissimus Dorsi
A: extends, adducts, and medially rotates the arm
Supraspinatus
A: assists with abduction of arm
Infraspinatus
A: laterally rotates arm
Subscapularis
A: medially rotates the arm
Deltoid
A: abducts the arm, flex the arm, medially rotate the arm
Teres Minor
A: laterally rotates the arm, extends the arm
Rotator Cuff
SITS
Supraspinatous
Infraspinatous
Teres Minor
Subscapularis
Biceps Brachii (long head, short head)
A: flexes forearm, supinates forearm, flexes arm at shoulder joint
O: short head originates from Coracoid Process
Brachialis
A: flexes forearm
Brachioradialis
A: flexes forearm
Triceps Brachii (long head, lateral head, medial head)
A: extends forearm, extends arm at the shoulder joint
I: Olecranon Process of the Ulna
Pronator Teres
A: pronates the forearm
Supinator
A: supinates the forearm
Pronator Quadratus
A: pronates forearm
Flexor Carpi Radialis
A: flexes ad abducts hand (radial deviation)
O: Medial Epicondyle of Humerus
Flexor Carpi Ulnaris
A: flexes and adducts the hand (ulnar deviation)
O: Medial Epicondyle of Humerus
Palmaris Longus
A: weakly flexes the hand
O: Medial Epicondyle of Humerus
Flexor Digitorum Superficialis
A: flexes middle and proximal phalanx of each finger, flexes hand
O: Medial Epicondyle of Humerus
Flexor Digitorum Profundus
A: flexes distal and middle phalanx of each finger, flexes hand
Flexor Pollicis Longus
A: flexes distal phalanx of thumb
Extensor Carpi Radialis Longus
A: extends and abducts hand
Extensor Carpi Radialis Brevis
A: extends and abducts hand
O: Lateral Epicondyle of Humerus
Extensor Carpi Ulnaris
A: extends wrist/hand, radial deviates hand
O: Lateral Epicondyle of Humerus
Extensor Digitorum
A: extends distal and middle phalanx of each finger, extends hand
O: Lateral Epicondyle of Humerus
Extensor Pollicis Longus
A: extends distal and middle phalanx of thumb, abducts hand
Extensor Pollicis Brevis
A: extends proximal phalanx of thumb, extends hand
External Obliques
Action bilaterally: flex abdomen/vertebral column
Action unilaterally: flex spine/trunk
Internal Obliques
Action bilaterally: flex abdomen/spine
Action unilaterally: laterally flex spine
Transverse Abdominus
A: compresses abdomen
Rectus Abdominus
A: flexes spine, compresses abdomen
Diaphragm
A: compresses abdomen, increases vertical dimension of thoracic cavity for inhalation to occur
Quadratus Lumborum
Action bilaterally: extend spine
Action unilaterally: laterally flex spine
External Intercostals
A: elevate ribs for inhalation
Internal Intercostals
A: depresses ribs with forceful expiration
Psoas Major
A: flex the thigh, rotate it laterally, flex trunk (like sitting up from supine position)
Iliacus
A: flex the thigh, rotate it laterally, flex trunk (like sitting up from supine position)
Gluteus Maximus
A: extend the thigh, extends torso, laterally rotates thigh
Gluteus Minimus
A: abducts thigh, medially rotates thigh
Tensor Fasciae Latae
A: flexes and abducts thigh
Iliotibial Tract
connects Tensor Fascia Latae to lower leg
Adductor Longus
A: adducts and flexes thigh
Adductor Magnus
A: adducts thigh, anterior part flexes thigh, posterior part extends thigh
Gracilis
A: adducts thigh, medially rotates thigh, flexes leg
Gluteus Minimus
A: abducts thigh, medially rotates thigh
Piriformis
A: laterally rotates and abducts thigh
I: Greater Trochanter of Femur
Biceps Femoris
A: flexes leg, extends thigh
Semimembranosus
A: flexes leg, extends thigh
Semitendinosus
A: flexes leg, extends thigh
Rectus Femoris
A: extend leg, flex thigh
O: AIIS
Vastus Lateralis
A: extend leg, flex thigh
Vastus Medialis
A: extend leg, flex thigh
Vastus Intermedius
A: extend leg, flex thigh
Sartorius
A: flexes leg, flexes thigh, abducts thigh, laterally rotates thigh
O: ASIS
Tibialis Anterior
A: dorsiflexion, inversion
Fibularis Longus
A: plantar flexion, eversion
Fibularis Brevis
A: plantar flexion, eversion
Gastrocnemius
A: plantar flexion, flexes leg
Soleus
A: plantar flexion
Tibialis Posterior
A: plantar flexion, inversion
Extensor Digitorum Longus
A: dorsiflexion, extends distal and middle phalanx of each toe
Extensor Hallucis Longus
A: dorsiflexion, extends proximal phalanx of great toe
Flexor Digitorum Longus
A: plantar flexion, flexes distal and middle phalanx of each toe
Flexor Hallucis Longus
A: plantar flexion, flexes distal and middle phalanx of great toe
Plantaris
A: plantar flexion, flexes leg
Calcaneal Tendon
aka “Achille’s Tendon”
Made of these 3 muscles:
Gastrocnemius
Soleus
Plantaris
Inserts onto the Calcaneus Bone