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8.4: MODELS- Head and Neck and Torso

  • Page ID
    59404
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    Name

    Action

    Origin

    Insertion

    Muscles of facial expression

    Frontalis (epicranius)

    Raises eyebrows , wrinkles forehead

    Frontal Bone

    Skin of the brow

    Occipitalis (epicranius)

    Pull scalp posteriorly

    Occipital bone

    Aponeurosis connecting to frontalis

    Orbicularis oris

    Closes mouth

    Maxillae and Mandible

    Lips

    Zygomaticus (major/minor)

    smile 

    Zygomatic Bone

    mouth

    Orbicularis oculi

    Closes eye

    Margin of Orbit

    Eyelid

    Masseter

    Elevates mandible

    Zygomatic Arch

    Mandible

    Temporalis

    Elevates mandible

    Temporal Bone

    Mandible

    Buccinator

    Presses cheek inward

    Maxillae and Mandible

    orbicularis oris

    Muscles of the head, vertebral column and abdominal wall

    Splenius capitis

    extend + laterally flex head

    upper spine

    Temporal & occipital

    Sternocleidomastoid

    Flexes + rotates neck (also elevates ribs)

    Sternum & Clavicle

    Mastoid Process

    Scalenes

    Flexes neck (also elevates ribs)

    Cervical Vertebrae

    1st Two Ribs

    Rectus abdominus

    Flexes vertebral column , compresses abdomen

    Pubis

    Lower Ribs and Xiphoid

    External oblique

    Flexes + rotates vertebral column,

    compresses abdomen

    Lower Ribs

    Linea alba and Ilium

    Internal oblique

    Flexes + rotates vertebral column, compresses abdomen

    Lumbar Vertebrae & Ilium

    Lower Ribs, Linea alba, Sternum

    Transverse abdominus

    Compresses abdomen

    Lower Ribs, Ilium, Lumbar

    Vertebrae

    Linea Alba & Pubis

    Erector spinae group

    Extends vertebral column

    Ilium, Sacrum, Ribs, Vertebrae

    Ribs, Vertebrae, Base of Skull

    Levator scapulae

    Extends neck (also elevates scapula)

    Cervical Vertebrae

    Scapula

    Name

    Action

    Origin

    Insertion

    Thoracic & shoulder muscles

    Pectoralis major

    Flexes, adducts + medially rotates arm at shoulder

    Sternum & Clavicle

    Humerus

    Pectoralis minor

    Elevates ribs (also moves scapula anterior and inferior)

    Ribs

    Scapula

    External intercostals

    Elevates ribs

    Inferior Rib

    Superior rib

    Internal intercostals

    Depresses ribs

    Superior rib

    Inferior Rib

    Diaphragm

    Increases thoracic volume

    Xiphoid Process, Ribs, Lumbar Vertebrae

    Central Tendinous Sheet

    Arm movers

    Serratus anterior

    Moves and fixes scapula anteriorly

    Ribs

    Scapula

    Trapezius

    Elevates, retracts, depresses+ rotates scapula upward (also extends neck)

    Occipital Bone & Thoracic Vertebrae

    Scapula

    Rhomboids (major & minor)

    Elevates + adducts scapula

    Cervical & Thoracic

    Vertebrae

    Scapula

    Latissimus dorsi

    Extends, adducts + medially rotates arm at shoulder

    Thoracic, Lumbar Vertebrae, Ribs

    Humerus

    Deltoid

    Abducts arm at shoulder (also anterior fibers flex + posterior fibers extend arm at shoulder)

    Clavicle & Scapula

    Humerus

    Teres major

    Medially rotate arm

    Scapula

    Humerus

    Rotator cuff (SITS)

    Infraspinatus

    Laterally rotates shoulder

    Scapula

    Humerus

    Supraspinatus

    Abducts shoulder

    Scapula

    Humerus

    Subscapularis

    Medially rotates shoulder

    Scapula

    Humerus

    Teres minor

    Laterally rotates shoulder

    Scapula

    Humerus


    This page titled 8.4: MODELS- Head and Neck and Torso is shared under a CC BY-SA license and was authored, remixed, and/or curated by Laird C. Sheldahl.

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