O & I: Neck Muscles Part 2

Question 1

Origin: Splenius

Answer 1

Nuchal ligament and spinous processes of C7-T6 vertebrae

Question 2

Insertion: Splenius

Answer 2

Splenius capitis: mastoid process of temporal bone and lateral third of superior nuchal line of occipital bone

Splenius Cervicis: tubercles of transverse processes of C1-C3 or C4 vertebrae

Question 3

Innervation: Splenius

Answer 3

Posterior rami of spinal nerves

Question 4

Action: Splenius

Answer 4

Acting unilaterally: laterally flex the neck and rotate the head to side of active muscles

Acting bilaterally: extend the head and neck

Question 5

Origin: Anterior Scalene

Answer 5

Transverse processes of C3-C6

Question 6

Insertion: Anterior Scalene

Answer 6

1st rib

Question 7

Innervation: Anterior Scalene

Answer 7

Cervical Spinal nerves C4-C6

Question 8

Action: Anterior Scalene

Answer 8

Flex Head

Question 9

Origin: Middle Scalene

Answer 9

Posterior rubercles of transverse processes of C5-C7

Question 10

Insertion: Middle Scalene

Answer 10

superior surface of 1st rib; posterior to groove for subclavian artery

Question 11

Innervation: Middle Scalene

Answer 11

Anterior rami of cervical spinal nerves

Question 12

Action: Middle Scalene

Answer 12

Flexes neck laterally at C2-C7; elevates 1st rib during forced inspiration

Question 13

Origin: Posterior Scalene

Answer 13

Posterior rubercles of transverse processes of C5-C7

Question 14

Insertion: Posterior Scalene

Answer 14

External border of 2nd rib

Question 15

Innervation: Posterior Scalene

Answer 15

Anterior rami of cervical spinal nerves of C7 & C8

Question 16

Action: Posterior Scalene

Answer 16

Flexes neck laterally at C2-C7; elevates 2nd rib during forced inspiration

Question 17

Origin: Platysma

Answer 17

Inferior border of mandible, skin, and subcutaneous tissues of lower face

Question 18

Insertion: Platysma

Answer 18

Fascia covering superior parts of pectoralis major and deltoid muscles

Question 19

Innervation: Platysma

Answer 19

Facial nerve (CN VII) via its branches of the parotid plexus

Question 20

Action: Platysma

Answer 20

Depresses mandible (against resistance); tenses skin of inferior face and neck (conveying tension and stress

Question 21

Origin (distal attach): Sternocleidomastoid (SCM)

Answer 21

lateral surfcae of mastoid process of temporal bone and lateral half of superior nuchal line

Question 22

Insertion (proximal attach): Sternocleidomastoid (SCM)

Answer 22

Sternal head: anterior surface of manubrium of sternum

Clavicular Head: superior surface of medial third of clavicle

Question 23

Innervation: Sternocleidomastoid (SCM)

Answer 23

Spinal Accessory nerve (CN XI; motor) & C2 and C3 nerves (pain and proprioception)

Question 24

Action: Sternocleidomastoid (SCM)

Answer 24

Unilateral Contraction: tilts head to same side (lateral flexion) and rotates it so face is turned superiorly toward opposite (contralateral) side

Bilateral contraction: (1) extends neck at atlantooccipital joints, (2) flexes cervical vertebrae so that chin approaches manubrium, or (3) extends superior cervical certebrae while flexing inferior vertebrae so chin is thrust forward with head kept level W/ cervical certebrae fixed, may elevate manubrium and medial ends of clavicles, assisting pumphandle action of deep respiration

Question 25

Origin: Omohyoid

Answer 25

Inferior border of Hyoid

Question 26

Insertion: Omohyoid

Answer 26

Superior border of scapula near suprascapular notch

Question 27

Innervation: Omohyoid

Answer 27

C1-C3 by a branch of ansa cervicalis

Question 28

Action: Omohyoid

Answer 28

depresses , retracts, and steadies hyoid