Myology of the Back

Question 1

The trapezius is innervated by what nerve?

Answer 1

the spinal accessory nerve

Question 2

What forms the spinal accessory nerve innervating the trapezius?

Answer 2

C1-C5 cord levels contribute to the spinal root of the spinal accessory nerve

Question 3

The latissimus dorsi is innervated by what nerve?

Answer 3

the thoracodorsal nerve

Question 4

What forms the thoracodorsal nerve innervating the latissimus dorsi?

Answer 4

ventral rami from C6-C8

Question 5

What forms the dorsal scapular nerve?

Answer 5

the ventral ramus of C5

Question 6

What is the innervation of the splenius capitis?

Answer 6

dorsal rami of middle cervical spinal nerves (C3-C5 cord levels)

Question 7

Splenius cervicis will attach to what locations on the spine?

Answer 7

lateral mass of C1 and posterior tubercle of transverse process on C1-C4

Question 8

Which muscles are identified as erector spinae or sacrospinalis muscles?

Answer 8

iliocostalis, longissimus, spinalis

Question 9

What is the innervation of the iliocostalis lumborum?

Answer 9

dorsal rami of lower thoracic and all lumbar spinal nerves

Question 10

What osseous parts of the vertebral column serve as an origin to the iliocostalis thoracis?

Answer 10

none

Question 11

What is the insertion for the iliocostalis thoracis?

Answer 11

costal angles of the upper 6-7 ribs, transverse process of C7

Question 12

What osseous parts of the vertebral column serve as an origin to the longissimus thoracis?

Answer 12

accessory process and transverse process of L1-L5, spinous processes of L3-L5 and median sacral crest S1-S3

Question 13

What is the innervation of longissimus cervicis?

Answer 13

dorsal rami C4-C8 and T1-T2 spinal nerves

Question 14

What osseous parts of the vertebral column serve as an origin to the spinalis thoracis?

Answer 14

spinous processes of T11 and T12-L1 and L2

Question 15

Which muscles are identified as transversospinalis muscles?

Answer 15

semispinalis, multifidis, and rotators

Question 16

How many vertebrae can be attached to a single segment by transversospinalis muscles?

Answer 16

as many as nine vertebrae

Question 17

What segment will represent the lowest attachment site for the semispinalis thoracis?

Answer 17

T12

Question 18

What osseous parts of the vertebral column serve as an origin to the semispinalis cervicis?

Answer 18

transverse tubercles of T1-T5 or T6 and articular processes of C4-C7

Question 19

What osseous parts of the vertebral column serve as an origin to the semispinalis capitis?

Answer 19

transverse tubercles of C7, T1-T6 or T7 and articular processes of C4-C6

Question 20

The semispinalis capitis and spinalis capitis may fuse to form what muscle?

Answer 20

biventer cervicis

Question 21

What osseous parts of the vertebral column serve as an origin to the classic multifidis?

Answer 21

articular process of C4-C7, transverse processes of T1-T12, mammillary processes of L1-L5 and the dorsal surface of S1-S4 or S5

Question 22

Contraction of the classic multifidis will result in what movements of the vertebral column?

Answer 22

lateral flexion and rotation of the spine, maintains the lumbar lordotic curve and prevents entrapment of zygapophyseal capsular ligament during movement

Question 23

Contraction of multifidis cervicis will result in what movements?

Answer 23

alters the zygapophyseal capsular ligament response to load distribution determines the cervical spine response to injury as evidenced by neck pain and is a significant contributor to postural control of the head and neck

Question 24

Contraction of multifidis lumborum will result in what movements?

Answer 24

lateral flexion and rotation of the lumbar spine, maintains the lumbar lordotic curve and prevents entrapment of lumbar zygapophyseal capsular ligament during movement

Question 25

Which muscles of the spine exhibit a reversal of the expected origin- insertion combination?

Answer 25

iliocostalis lumborum pars lumborum, longissimus thoracic pars lumborum and multifidis lumborum

Question 26

Rotator muscles are typically identified in what region of the spine?

Answer 26

the thoracic region

Question 27

Which suboccipital muscle lacks an attachment to the skull?

Answer 27

obliquus capitis inferior

Question 28

Which nerve will innervate all suboccipital muscles?

Answer 28

dorsal ramus of C1, the suboccipital nerve

Question 29

What is the origin of the obliquus capitis inferior?

Answer 29

C2 spinous process and lamina

Question 30

An increase in the density of muscle spindles is most apparent in which suboccipital muscle?

Answer 30

obliquus capitis inferior

Question 31

What is the proposed function of the suboccipital muscle group?

Answer 31

postural stabilizers of the atlanto-occipital and atlanto-axial joints

Question 32

Which suboccipital muscles are known to attach to dura mater?

Answer 32

rectus capitis posterior major, rectus capitis posterior minor and obliquus capitis inferior

Question 33

Interspinalis is paired in which regions of the spine?

Answer 33

cervical and lumbar regions

Question 34

Based on the density of muscle spindles what is the proposed function of the interspinalis?

Answer 34

acts as a proprioceptive transducer in conjunction with intertransversarii to coordinate the smooth movement of the spine and to maintain appropriate posture

Question 35

Which is the cervical intertransversarii is innervated by dorsal rami of cervical spinal nerves?

Answer 35

posterior medial belly, cervical intertransversarii

Question 36

What is the origin of the medial belly of the lumbar intertransversarii?

Answer 36

accessory process of transverse process L1-L4 and mammillary process of superior articular process L1-L4

Question 37

Which muscle group in innervated by both dorsal rami and ventral rami of spinal nerves?

Answer 37

intertransversarii

Question 38

Based on the density of muscle spindles what is the proposed function of the intertransversarii?

Answer 38

acts as a proprioceptive transducer in conjunction with interspinalis to coordinate the smooth movement of the spine and to maintain appropriate posture

Question 39

What is the origin of longus colli?

Answer 39

vertebral bodies of C5-C6, T1-T3 and anterior tubercles of transverse processes C3-C5

Question 40

What is the origin of the rectus capitis anterior?

Answer 40

lateral mass and costal element of the transverse process of C1

Question 41

What will innervate the rectus capitis anterior?

Answer 41

ventral rami of C1-C2 spinal nerves

Question 42

What will innervate the rectus capitis lateralis?

Answer 42

ventral rami of C1-C2 spinal nerves

Question 43

What is the insertion of the anterior scalene?

Answer 43

ridge and anterior scalene tubercle of the first rib

Question 44

What is the insertion of the middle scalene?

Answer 44

between the tubercle and groove for the subclavian artery on the first rib

Question 45

What is the insertion of the posterior scalene

Answer 45

outer surface of second rib

Question 46

What will innervate the posterior scalene?

Answer 46

the ventral rami of C6-C8 spinal nerve

Question 47

The quadratus lumborum is implicated in the formation of which ligament?

Answer 47

the iliolumbar ligament

Question 48

What is the origin of the psoas major?

Answer 48

vertebral bodies T12, L1-L5, S1 and transverse processes of L1-L5

Question 49

What is the origin of psoas minor?

Answer 49

vertebral bodies T12, L1

Question 50

What will innervate the psoas minor?

Answer 50

the ventral ramus of L1 spinal nerve