Muscles of Chapter 24-26

What is the primary function of the Epicranius

To raise the eyebrows

What is the primary function of the Orbicularis Oculi

To close the eyelid

What is the primary function of the Orbicularis Oris

To close or “purse” the lips

What is the primary function of the Zygomaticus Major

To elevate and retract corners of the mouth

What is the origin of the Zygomaticus Major

The origin is the Zygomatic bone

What is the insertion of the Zygomaticus Major?

The superolateral region of the mouth

What is the primary function of the Masseter

The primary action is to elevate the mandible

What is the origin of the Masseter

The Zygomatic arch and Maxilla

What is the insertion of the Masseter

The Angle and Ramus of the Mandible

What is the primary function of the Temporalis?

To elevate the Mandible

What is the origin of the Temporalis

The Parietal bone

What is the insertion of the Temporalis

Coronoid Process of the Mandible

What is the primary function of the Platysma

To depress the Mandible

What does the Superior Rectus do?

Rotates the eye to look Superiorly

What does the Inferior Rectus do?

Rotates the eye to look inferiorly

What does the Medial Rectus do?

Rotates the eye to look medially

What does the Lateral Rectus do?

Rotates the eye to look laterally

What is the primary function of the Sternocleidomastoid

There are two functions depending on if one or both muscles contraction:

One Muscle: The head rotates contralaterally

Both Muscles: The head flexes

What is the origin of the Sternocleidomastoid

The Manubrium and Clavicle

What is the insertion of the Sternocleidomastoid

The Mastoid process

What is the primary function of the Splenius Capitis

There are two functions depending on if one or both muscles contraction:

One Muscle: The head rotates ipsilaterally

Both Muscles: The head extends

What is the primary function of the Diaphram

Inhalation

What is the primary function of the External Intercostals

Elevates the Rib cage for inhalation

What is the primary function of the Internal Intercostals

Depresses the Ribs for exhalation

What is the primary function of the Erector Spinae

Extends the vertebral column

What is the primary function of the Rectus Abdominis

Flexes the vertebral column

What is the origin of the Rectus Abdominis

The Pubis

What is the insertion of the Rectus Abdominis

The Xiphoid process (and some costal cartilages)

What is the primary function of the External Oblique

There are two functions depending on if one or both muscles contraction:

One Muscle: Trunk rotates ipsilaterally

Both Muscles: Vertebral column flexes

What is the primary function of the Internal Oblique

There are two functions depending on if one or both muscles contraction:

One Muscle: Trunk rotates contralaterally

Both Muscles: Vertebral column flexes

What is the primary function of the Transversus Abdominis

To compress the abdomen

What is the primary function of the Pectoralis Minor

To protract and depress the scapula

What is the origin of the Pectoralis Minor

On Ribs 3-5

What is the insertion of the Pectoralis Minor

The Coracoid process of Scapula

What is the primary function of the Serratus Anterior

Protract the Scapula (also holds the scapula in place)

What is the primary function of the Trapezius (Superior, middle , and inferior)

Superior: Elevates the Scapula

Middle: Retracts Scapula
Inferior: Depresses Scapula

What is the primary function of the Pectoralis Major

Flexes and Adducts the arm

What is the primary function of the Latissimus Dorsi

Extends and adducts arm

What is the primary function of the Deltoid

Abducts the arm

What is the origin of the Deltoid

The Clavicle, Acromion, and Spine of Scapula

What is the insertion of the Deltoid

Deltoid Tuberosity of Humerus

What is the primary function of the Teres Major

Adducts and extends the arm

What is the primary function of the Subscapularis

Medially rotates the arm

What is the primary function of the Supraspinatus

Abducts the arm

What is the primary function of the Infraspinatus

Adducts and Laterally rotates the arm

What is the primary function of the Teres Minor

Adducts and laterally rotates the arm

What is the primary function of the Biceps Brachii

To Flex the Forearm

What is origin of the Biceps Brachii

Coracoid Process and Edge of Glenoid Cavity

What is the insertion of the Biceps Brachii

Radial Tuberosity

What is the primary function of the Brachialis

Flex the Forearm

What is the primary function of the Brachioradialis

Flexes the foramen

What is the primary function of the Triceps Brachii

Extends the Forearm

What is the origin of the Triceps Brachii

The Scapula and Posterior Shaft of Humerus

What is the insertion of Triceps Brachii

Olecranon Process

What is the primary function of the Supinator

Supination of Forearm

What is the primary function of the Pronator Teres

Pronation of the Forearm

What is the primary function of the Flexor Carpi Radialis?

To flex and abduct the hand

What is the primary function of the Flexor Carpi Ulnaris

Flexes and adducts the hand

What is the primary function of the Extensor Carpi Radialis Longus

Extends the hand and abducts the hand.

What is the primary function of the Extensor Carpi Ulnaris

Extends and adducts the hand

What is the primary function of the Iliacus

To flex the thigh

What is the primary function of the Sartorius

Flexes and laterally rotates the thigh

What is the primary function of the Adductor Magnus

Adducts the thigh

What is the primary function of the Adductor Longus

Adducts the Thigh

What is the primary function of the Gracilis

Adducts the Thigh

What is the primary function of the Tensor Fascia Latae

Flexes and Abducts the thigh

What is the primary function of the Gluteus Maximus

Extends Thigh

What is the primary function of the Gluteus Medius

Abducts the thigh

What is the origin of the Gluteus Medius

Lateral surface of Ilium

What is the insertion of the Gluteus Medius

Greater Trochanter of Femur

What is the primary function of the Rectus Femoris

Extends the Leg

What is origin of the Rectus Femoris

The origin is the ilium

What is the insertion of the Rectus Femoris

The insertion is the patella

What is the primary function of the Vastus Lateralis

Extends the leg

What is the primary function of the Vastus Medialis

Extends the leg

What is the primary function of the Vastus Intermedius

Extends the leg

What is the primary function of the Biceps Femoris

Flexes the leg

What is the origin of the Biceps Femoris

The origin on the Ischial Tuberosity and Linea Aspera

What is the insertion of the Biceps Femoris

The insertion is on The Head of Fibula and Lateral Condyle of Tibia

What is the primary function of the Semitendinosus?

Flexes the leg

What is the primary function of the Semimembranosus

Flexes the leg

What is the primary function of the Tibialis Anterior

Dorsiflexion

What is the primary function of the Gastronemius

Plantar Flexion

What is the origin of the Gastrocnemius

Medial and Lateral Condyles of Femur

What is the insertion of Gastrocnemius

Achilles Tendon (Also known as Calcaneal tendon)

What is the primary function of the Soleus

Plantar Flexion