Muscles: Location and Action

Action of Frontalis

Elevates eyebrows

Action of Occipitalis

Pulls scalp posteriorly

Action of Orbicularis Oculi

Closes the eye

Action of Orbicularis oris

Closes and protrudes the lips

Action of Platysma

Depresses lower lip and opens mouth by depressing mandible

Action Zygomaticus Major

Pulls the angle of the mouth superiorly and laterally

Action of Zygomaticus minor

Elevates lateral portion of upper lip

Action of Risorius

Pulls angle of mouth laterally to make closed mouth smile or smirk

Action of Lateral Pterygoid

Protracts and depresses the mandible

Action of Medial Pterygoid

Elevates and protracts the mandible

Action of Buccinator

Pulls the cheeks in

Action of Temporalis

Elevates and retracts mandible

Action of Masseter

Elevates the mandible

Action of Sternocleidomastoid

Together they flex the head; individually the flex and rotate head towards opposite side

Action of Scalenes

Move head laterally when contacted individually; elevates rib cage when vertebral column is fixed

Action of Trapezius in head

Extends the head

Action of Iliocostalis Thoracis

Extends the vertebral column; maintains posture; laterally flexes vertebral column when contracting only one side

Action of Longissimus Thoracis

Extends the vertebral column; laterally flex vertebral column when contracting only one side

Action of Spinalis Thoracis

Extends vertebral column

Action of Trapezius (all sections)

Retracts and depresses scapula; rotates scapula superiorly; elevates scapula

Action of Latisimus Dorsi

Adducts and extends the arm; rotates arm medially

Action of Quadratus Lumborum

Extends the vertebral column; laterally flexes vertebral column when contracted individually

Action of Rectus Abdominis

Flexes the trunk; compresses abdominal cavity

Action of External Oblique

Flexes and laterally flexes trunk; compresses abdominal cavity

Action of Internal Oblique

Flexes and laterally flexes trunk; compresses abdominal cavity

Action of Transverse Abdominis

Compress abdominal cavity

Action of Pectoralis Major

Flexes and adducts arm; rotates arm medially

Action of Serratus Anterior

Prime mover of scapula in protraction; assists in superior rotation of scapula

Action of Pectoralis Minor

Protracts and depresses scapula

Action of Levator Scapulae

Elevates scapula

Action of Rhomboid Major

Retracts scapula

Action of Rhomboid minor

Retracts scapula

Action of Deltoid

Abducts the arm; secondary flexes and extends arm

Action of Supraspinatus

Assists abduction; holds humerus; stabilizes shoulder joint

Action of Infraspinatus

Laterally rotates the humerus; stabilizes shoulder joint

Action of Teres Minor

Laterally rotates the humerus; stabilizes shoulder joint

Action of Triceps Brachii

Extends the forearm

Action of Biceps Brachii

Supinates the forearm; flexes the forearm

Action of Brachialis

Flexes the forearm (prime mover)

Action of Flexor Digitorum Superficialis

Flexes the fingers; flexes the hand

Action of Flexor Carpi Ulnaris

Flexes the hand; adducts the hand

Action of Palmaris Longus

Flexes the hand; tenses the dense connective tissue in palm of hand

Action of Flexor Carpi Radialis

Flexes hand toward anterior forearm; abducts hand

Action of Pronator Teres

Pronates forearm

Action of Brachioradialis

Flexes the forearm

Action of Extensor Carpi Radialis Longus

Extends the hand; abducts the hand

Action of Extensor Carpi Radialis Brevis

Extends the hand; abducts the hand

Action of Extensor Digitorum

Extends the fingers; extends the hand

Action Extensor Digiti Minimi

Extends the fifth finger

Action of Extensor Carpi Ulnaris

Extends the hand; adducts the hand

Action of Iliacus

Flexes thigh

Action of Psoas Major

Flexes thigh; flexes and laterally flexes the vertebral column

Action of Sartorius

Flexes the thigh and flexes the leg; abducts and laterally rotates the thigh

Action of Rectus Femoris

Extends the leg; flexes the thigh

Action of Vastus Intermedius

Extends the leg

Action of Vastus Medialis

Extends the leg; stabilizes patella

Action of Vastus Lateralis

Extends the leg; stabilizes the patella

Action of Adductor Longus

Adducts the thigh; flexes thigh; rotates thigh

Action of Gracilis

Adducts the thigh; flexes the leg; rotates the thigh

Action of Gluteus Maximus

Extends the thigh; laterally rotates the thigh; abducts thigh

Action of Gluteus Medius

Abducts the thigh; medially rotates the thigh; stabilizes the pelvis while walking

Action of Biceps Femoris

Extends the thigh; flexes the leg

Action of Semitendinoses

Extends the thigh; flexes the leg

Action of Semimembranosus

Extends the thigh; flexes the leg

Action of Fibularis Longus

Everts the foot; planterflexes the foot

Action of Tibialis Anterior

Dorsiflexes the foot; inverts the foot

Action of Soleus

Plantarflexes the foot

Action of Gastrocnemius

Plantarflexes the foot; flexes the leg

Action of Fibularis Longus

Everts the foot; plantarflexes the foot

Action of Fibularis Brevis

Everts the foot; plantarflexes the foot

Action of Extensor Digitorum Longus

Extends the toes; dorsiflexes the foot

Action of Extensor Hallucis Longus

Extends the hallux; dorsiflexes the foot

Erector Spinae: I Long for Spinach

Iliocostalis Thoracis, Longissimus Thoracis, Spinalis Thoracis

Main Abdominal Muscles: “Spare TIRE”

Transverse abdominis, Internal oblique, Rectus abdominis, External oblique

Rotator Cuff: SITS

Supraspinatus, Infraspinatus, Teres minor, Subscapularis

Iliopsoas: Party Indeed

Psoas major, Iliacus

Quadriceps Femoris: Really Lazy Interns Memorize

Rectus Femoris, Vastus Lateralis, Vastus Intermedius, Vastus Medialis

Hamstrings: Be Smart Sometimes

Biceps femoris, Semitendinosus, Semimembranosus

Epicranial aponeuroses

Extensor hallucis longus

Extensor digitorum longus

Fibularis longus

Achillies’ tendon

Gastrocnemius

Soleus

Tibialis anterior

Fibularis longus

Semimembranosus

Semitendinosus

Biceps femoris

Gluteus Medius

Gluteus maximus

Patellar tendon

Gracilis

Adductor longus

Vastus medialis

Vastus intermedius

Vastus lateralis

Rectus Femoris

Sartorius