Functional Anatomy - Neck (Detailed)

Question 1

State the origin, insertion, isometric, concentric and eccentric functions for the muscle in yellow:

Answer 1

STERNOCLEIDOMASTOID

ORIGIN
Sternal head: top of manubrium of the sternum; Clavicular head: Medial
one-third of the clavicle

INSERTION
Mastoid process, lateral superior nuchal line of the occiput of the skull

ISOLATED FUNCTION
Concentric Action
Cervical flexion, rotation, and lateral flexion

Eccentric Action
Cervical extension, rotation, and lateral flexion

Isometric Action
Stabilizes the cervical spine and acromioclavicular joint

INNERVATION
Cranial nerve XI

Question 2

State the origin, insertion, isometric, concentric and eccentric functions for the muscle in yellow:

Answer 2

SCALENES

ORIGIN
Transverse processes of C3–C7

INSERTION
First and second ribs

ISOLATED FUNCTION
Concentric Action
Cervical flexion, rotation, and lateral flexion; Assists rib elevation during
inhalation

Eccentric Action
Cervical extension, rotation, and lateral flexion

Isometric Action
Stabilizes the cervical spine

INNERVATION
Ventral rami (C3–C7)

Question 3

State the origin, insertion, isometric, concentric and eccentric functions for the muscle in yellow:

Answer 3

LONGUS COLLI

ORIGIN
Anterior portion of T1–T3

INSERTION
Anterior and lateral C1

ISOLATED FUNCTION
Concentric Action
Cervical flexion, lateral flexion, and ipsilateral rotation

Eccentric Action
Cervical extension, lateral flexion, and contralateral rotation

isometric Action
Stabilizes the cervical spine

INNERVATION
Ventral rami (C2–C8)

Question 4

State the origin, insertion, isometric, concentric and eccentric functions for the muscle in yellow:

Answer 4

LONGUS CAPITIS

ORIGIN
Transverse processes of C3–C6

INSERTION
Inferior occipital bone

ISOLATED FUNCTION
Concentric Action
Cervical flexion and lateral flexion

Eccentric Action
Cervical extension

Isometric Action
Stabilizes the cervical spine

INNERVATION
Ventral rami (C1–C3)