Head and Neck Muscles Origins/Insertions/Actions

Temporalis Origin and Insertion

Origin: Temporal fossa

Insertion: Mandible

Temoralis Action

Elevates and retracts the mandible

Masseter Origin and Insertion

Origin: Zygomatic Arch

Insertion: Mandible

Masseter Action

Elevates and protrudes mandible

Medial Pterygoid Origin and Insertion

Origin: pterygoid plate of sphenoid bone (also maxilla and palatine)

Insertion: Mandible

Medial Pterygoid Action

Action: Elevates and protrudes mandible, side to side grinding

Lateral Pterygoid Origin and Insertion

Origin: pterygoid plate of sphenoid bone

Insertion: Mandible

Sternocleidomastoid

Origin: Sternal head, clavicular head

Insertion: Mastoid process of temporal bone

Sternocleidomastoid Action

Bilaterally: Anterior neck flexion

Unilaterally: Ipsilateral (same sided) lateral flexion of the neck and contralateral (different sided) rotation. 

Lateral pterygoid Action

Depresses and protrudes the mandible

Splenius capitis

Origin: Ligamentum nucha and spinous process of thoracic vert 1-3

Insertion: Mastoid process of temporal bone

Spelnius Capitis Action

Bilaterally: Neck extension

Unilaterally: Ipsilateral neck flexion/rotation

Anterior/Middle Scalene

Origin: Cervical vertabrae

Insertion: First Rib

Anterior/Middle Scalene Action

Elevation of first rib (inspiration)

Ipsilateral neck flexion/rotation

Posterior scalene

Origin: Cervical vertabrae

Insertion: 2nd Rib

Posterior scalene action

Elevation of second rib (inspiration) inhaling

Unilaterally: Neck flexion and rotation

Anterior Digastric belly

Origin: Mandible

Insertion: Hyoid (via tendon)

Anterior Digastric belly Actions

Elevate hyoid and larynx and depresses mandible

Posterior Digastric Belly Action

Origin: Mastoid process

Insertion: Hyoid

Stylohyoid

Origin: Styloid

Insertion: Hyoid

Stylohyoid Action

Elevation of hyoid and larynx

Mylohyoid

Origin: Mandible

Insertion: Hyoid

Mylohyoid action

Elevation Hyoid and larynx (also forces food back) muscular floor of mouth

Geniohyoid

Origin: Genial spine of mandible

Insertion: Hyoid

Geniohyoid action

Elevate hyoid and larynx

Omohyoid

Origin: scapula and clavicle

Insertion: hyoid

Omohyoid

Depresses hyoid

Sternohyoid Origin/Insertion/Action

Origin: Manubrium sternum and clavicle

Insertion: Hyoid

Action: Depresses hyoid

Thyrohyoid Origin/Insertion/Action

Origin: Thyroid

Insertion:Hyoid

Action: Depresses hyoid

Superior Rectus Origin/Insertion/Action

Origin: sphenoid

Insertion: sclera of eye

Action: Eye looks superior/medial

Inferior rectus Origin/Insertion/Action

Origin: sphenoid

Insertion: sclera of eye

Action: Eye looks inferior/medial

Medial rectus

Origin: sphenoid

Insertion: sclera of eye

Action: Eye looks medial (adduction)

Lateral rectus

Origin: maxilla

Insertion: sclera of eye

Action: Eye looks lateral (abduction)

External Intercostals

Origin: Superior Rib

Insertion: Inferior Rib

Action: Elevate ribs for inhalation

Internal Intercostals

Origin: Inferior rib

Inhalation: Superior rib

Depresses rib for exhalation

Diaphragm

Origin: Sternum, costal cartilages, ribs 7-12, lumbar vertabrae

Insertion: central tendon

Action: Increase volume of thoracic cavity which will increase IAP

Pre-vertebral muscles

Flexes head, neck trunk

Post-vertabral muscles

Extends head, neck, trunk

Superior Oblique

Origin: Sphenoid

Insertion: Sclera of eye

Action: Eye looks inferior and lateral intorsion ( eye roll in)

Inferior oblique

Origin: Maxilla

Insertion: Sclera of eye

Action: looks superiority and lateral extortion

External Oblique

Origin: Lower 8 ribs

Insertion: Iliac crest and linea alba

Action: lateral flexion and rotation of trunk increase IAP

Transverse Abdominis

Increase IAP

Rectus Abdominis

Anterior Trunk Flexion and increased IAP

Psoas major

Origin: T12 of lumbar vertabrae

Insertion: Lesser trochanter of femur

Bilaterally: Anterior flexion of trunk

Unilaterally: Flexion of thigh and ipsilateral flexion of trunk

iliacus

Origin: Iliac fossa

Insertion: Lesser trochanter of femur

Action:

Bilaterally: Anterior flexion of trunk

Unilaterally: flexion of thigh

Quadratus lumborum

Origin: iliac crest

Initiation: Rib 12/ Lumbar vertabrae

Action: 

Bilaterally: extension of vertebral column

Unilaterally: Ipsilateral flexion of vertebral trunk

Deltoid

Origin: Clavicle, acromion, spine of scapula

Insertion: deltoid tuberosity of humerus

Action:

1. Abduction of arm

2. Flexion and medial rotation of arm (Anterior fibers)

3. Extensor and lateral rotation (Posterior fibers)

Pectoralis major

Origin: Clavicle, sternum, costal cartilages 1-6

aponeurosis of external oblique

Insertion: Hummerus

Action: Flexion/ adduction and medial rotation

Latissimus dorsi

Thoracolumbar facia, lower thoracic and lumbar vertabrae and iliac crest, lower 3 ribs

Insertion: humerus

Action: Extension addictoon and medial rotation of arm (swimming)

Trapezius

Origin: Occipital bone, ligamental nuchae all thoracic vertebrae

Insertion: Clavicle and acromion and spine of scapula

Actions:

Adduction and rotation of scapula

Inferior fibers: Depression of scapula

Superior fibers: Elevation of scapula

Bilaterally: Extension of head and neck

Unilaterally: Ipsilateral flexion of neck

Serratus anterior

Origin;Ribs 1-8 anteriorly

Insertion: vertebral border of scapula

Action: stabilizes scapula

protraction and upward rotPectation of scapula (push up and punch)

Pectoralis minor

Origin: Ribs 3-5

Insertion: Coracoid process of scapula

Action: Depression and protraction scapula elevation of ribs

Levator scapulae

Origin: Cevical vertabrae

Insertion: Scapula

Action: Elevates and adducts scapula

Rhomboid major/minor

Origin: Thoracic vertebrae

Insertion: Scapula

Action: Retraction and adduction of scapula

Teres major

Origin: Scapula

Insertion: Humerus

Action: Adduction, and extenstion and medial rotation of arm

Supraspinatus

Origin: Supraspinous fossa of scapula

Insertion: Greater tubercle of hume