Posterior Neck Muscles

Question 1

Sternocleidomastoid (SCM) Sternal Head Origin

Answer 1

Lateral surface of mastoid process of temporal bone and lateral half of superior nuchal line

Question 2

Sternocleidomastoid (SCM) Sternal Head Insertion

Answer 2

Anterior surface of manubrium of sternum

Question 3

Sternocleidomastoid (SCM) Sternal Head Innervation

Answer 3

Spinal accessory nerve (CN XI, motor); C2 and C3 nerves (pain and proprioception)

Question 4

Sternocleidomastoid (SCM) Sternal Head Unilateral Action

Answer 4

Tilts head to same side (i.e., laterally flexes neck) and rotates it so face is turned superiorly toward opposite side

Question 5

Sternocleidomastoid (SCM) Sternal Head Bilateral Contraction Action

Answer 5

(1) Extends neck at atlanto-occipital joints (2) flexes cervical vertebrae so that chin approaches manubrium or (3)

Question 6

Trapezius Superior Fibers Origin

Answer 6

Medial third of superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7-T12 vertebrae, and lumbar and sacral spinous processes

Question 7

Trapezius Superior Fibers Insertion

Answer 7

Lateral third of clavicle, acromion, and spine of scapula

Question 8

Trapezius Superior Fibers Innervation

Answer 8

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

Question 9

Trapezius Superior Fibers Action

Answer 9

Elevates, retracts, and rotates scapula superiorly. Descending (superior)fibers: elevate pectoral girdle, maintain level of shoulders against gravity or resistance

Question 10

Splenius Capitis Origin

Answer 10

Inferior half of nuchal ligament and spinous processes of superior six thoracic vertebrae

Question 11

Splenius Capitis Insertion

Answer 11

Lateral aspect of mastoid process and lateral third of superior nuchal line

Question 12

Splenius Capitis Innervation

Answer 12

Posterior rami of middle cervical spinal nerves

Question 13

Splenius Capitis Action

Answer 13

Laterally flexes and rotates head and neck to same side; acting bi-laterally extends head and neck

Question 14

Levator Scapulae Origin

Answer 14

Posterior tubercles of transverse processes C2-C6 vertebrae

Question 15

Levator Scapulae Insertion

Answer 15

Superior part of medial border of scapula

Question 16

Levator Scapulae Innervation

Answer 16

Dorsal scapular nerve C5 and cervical spinal nerves C3 and C4

Question 17

Levator Scapulae Action

Answer 17

Downward rotation of scaula and tilts its glenoid cavity inferiorly by rotating scapula

Question 18

Anterior Scalene Origin

Answer 18

Transverse processes of C3-C6 vertebrae

Question 19

Anterior Scalene Insertion

Answer 19

1st rib

Question 20

Anterior Scalene Innervation

Answer 20

Cervical spinal nerves C4-C6

Question 21

Anterior Scalene Action

Answer 21

Flex head

Question 22

Anterior Scalene Root

Answer 22

C4-C6

Question 23

Middle Scalene Origin

Answer 23

Posterior tubercles of transverse processes of C5-C7 vertebrae

Question 24

Middle Scalene Insertion

Answer 24

Superior surface of 1st rib; posterior to groove for sub-clavian artery

Question 25

Middle Scalene Innervation

Answer 25

Anterior rami of cervical spinal nerves

Question 26

Middle Scalene Action

Answer 26

Flexes neck laterally; elevates 1st rib during forced inspiration

Question 27

Middle Scalene Root

Answer 27

C7,C8

Question 28

Posterior Scalene Origin

Answer 28

Posterior tubercles of transverse processes of C5-C7 vertebrae

Question 29

Posterior Scalene Insertion

Answer 29

External border of 2nd rib

Question 30

Posterior Scalene Innervation

Answer 30

Anterior rami of cervical spinal nerves C7 and C8

Question 31

Posterior Scalene Action

Answer 31

Flexes neck laterally; elevates 2nd rib during forced inspiration

Question 32

Posterior Scalene Root

Answer 32

C7,C8