Section 3: Muscle Functions

Biceps Brachii
Flexion at elbow joint
Flexion at elbow joint to flex forearm
Triceps Brachii
Extension at elbow joint to extend forearm
Flexion at elbow; supination and pronation of forearm
Pronator Teres
Pronates the forearm and weak flexion at elbow joint
Flexor Carpi Radialis
Flexion at wrist; abduction of hand
Palmaris Longus
Flexion at wrist; weak flexion at elbow joint
Extensor Digitorum
Extension at wrist
Psoas Major
Flexion at hip joint, bends lumbar vertebral column
Flexion and external rotation at hip joint
Gluteus Maximus
Extension of flexed femur in hip joint
Gluteus Medius
Abducts the hip and stabilizes pelvis
Rectus Femoris
Flexion at hip joint; extension at knee joint
Vastus Lateralis
Extension at Knee joint; lateral
Vastus Medialis
Extension at knee joint; medial
Vastus Intermedius
Extension at knee joint; beneath rectus femoris
Flexion, abduction and external rotation at hip joint
Tensor Fasciae Latae
Abduction, flexion and internal rotation at hip joint
Adduction and flexion at hip joint; flexion and internal rotation at knee joint
Adductor Magnus
Adduction, extension, weak flexion, internal rotation and stabilization of pelvis
Adductor Longus
Adduction and Flexion at Hip Joint
Biceps Femoris
Flexion and external rotation at knee joint
Extension at hip joint; stabilization of pelivs; flexion and internal rotation at knee joint
Extension at hip joint; stabilization of pelvis; flexion and internal rotation in knee joint; medial
Tibialis Anterior
Dorsal flexion at talocrural joint and inversion at sub talar joint
Extensor Digitorum Longus
Dorsal flexion at talocrural joint, eversion in subtalar joint
Fibularis Longus
Eversion and plantar flexion of ankle
Plantar flexion at talocrural joint and plantar flexion of foot
Plantar flexion at talocrural joint; flexion at knee joint
Inclines head ipsilaterally, rotates contralaterally
Elevates hyoid bone, depresses the mandible
Elevates and draws the hyoid bone forward; elevates the tongue; depresses the mandible
Depresses and stabilizes the hyoid; elevates larynx during swallowing
Pectoralis Major
Prime mover of arm flexion
Pectoralis Minor
Draws scapula forward and inferiorly
Serratus Anterior
Prime mover to protract and hold scapula against chest wall; rotates scapula
External Intercostals
Pull ribs toward one another to elevate rib cage
Internal Intercostals
Draw ribs together to depress rib cage
Prime mover of inspiration flattens on contraction
Raises Brow
Pulls Scalp posteriorly
Elevation and retraction of mandible
Elevation and protraction of mandible
Compresses cheeks against teeth
ex: Blowing, Chewing
Orbicularis Oris
Used to pucker lips
Draws angle of mouth upward and laterally
Draw back angle of mouth
Depressor anguli oris
Depresses angle of mouth
Elevates and wrinkles skin of chin, protrudes lower lip
Levator labii superioris
Elevates upper lip
Orbicularis Oculi
Closes eyelids
Point of derivation; more fixed portion of a muscle
point of attachment of a muscle to the bone it moves
Muscle with main movement
Assists prime mover
Opposes prime mover
Manubrium sterni
Origin of Sternocleidomastoid
Mastoid Process
Insertion of Sternocleidomastoid
Medial Half of Clavicle, Manubrium, Body of Sternum
Origin of Pectoralis Major
Crest of Greater Tubercle of Humerus
Insertion of Pectoralis Major
Superior Rib
Origin of External Intercostals
Inferior Rib
Insertion of External Intercostals
Xiphoid Process
Origin of Diaphragm
Central Tendon
Insertion of Diaphragm
Inferior angle of scapula
Origin of Latissimus Dorsi
Crest of Lesser Tuberosity of Humerus
Insertion of Latissimus Dorsi
Origin of Deltoid
Deltoid Tuberosity of Humerus
Insertion of Deltoid
Pubis and Pubic Symphysis
Origins of Rectus Abdominis
Xiphoid Process
Insertions of Rectus Abdominis
Coracoid Process of Scapula
Origin of Short Head of Biceps Brachii
Supraglenoid Tubercle of Scapula
Origin of Long Head of Biceps Brachii
Radial Tuberosity
Insertion of Biceps Brachii
Lateral Epicondyle of Humerus
Origin of Extensor Digitorum
2nd and 5th digits
insertion of extensor digitorum
Origin of Gluteus Maximus
Gluteal Tuberosity of Femur
Insertion of Gluteus Maximus
Anterior Inferior Iliac Spine
Origin of Rectus Femoris
Tibial Tuberosity and Patella
Insertion of Rectus Femoris
Greater Trochanter of Femur
Origin of Vastus Lateralis
Tibial Tuberosity and Patella
Insertion of Vastus Lateralis
Ischial Tuberosity
Origin of Biceps Femoris
Head of Fibula and Lateral Condyle of Tibia
Insertion of Biceps Femoris
Head of Fibula
Origin of Fibularis Longus
First Metatarsal
Insertion of Fibularis Longus
Origin of Gastrocnemius
Calcaneal Tendon
Insertion of Gastrocnemius