Dermatomes and myotomes

Question 1

What does the sclerotome give rise to

Answer 1

Vertebrae and ribs

Question 2

What forms the dermatomyotome

Answer 2

Dorsal surface of somites

Question 3

What does the dermatomyotome give rise to

Answer 3

Dermis and muscle

Question 4

What is a neural level

Answer 4

Neural segment of the CNS

Question 5

Development of DMT Innervation

Answer 5

DMT develops in association with a specific neural level and takes nerve supply from the neural tube with it as a spinal (segmental) nerve

Question 6

What are spinal nerves

Answer 6

Parallel bundles of motor and sensory axons encased in CT

Question 7

What divides CNS and PNS

Answer 7

Intervertebral foramen

This marks termination of spinal nerves

Question 8

How many spinal nerves exist

Answer 8

31 pairs

Question 9

How are spinal nerves named

Answer 9

According to level of vertebral column from which it emerges

Question 10

What do spinal nerve roots connect

Answer 10

Each spinal nerve to a segment of the spinal cord

Question 11

What do dorsal and ventral roots contain

Answer 11

Dorsal - afferent nerve fibres

Ventral - efferent nerve fibres

Question 12

What is the dorsal root ganglion

Answer 12

Collection of cell bodies of afferent neurones in the PNS

Question 13

Where does the spinal cord run from and to

Answer 13

Start - inferior margin of medulla oblongata

End - conus medullaris at L2

Question 14

Where do the long roots of lumbar sacral and coccygeal segments descend before exiting at respective intervertebral foramina

Answer 14

Cauda equina

Question 15

Where do C1 spinal nerves emerge

Answer 15

Between occipital bone and atlas

Question 16

Where do C2-7 spinal nerves emerge

Answer 16

Above their corresponding vertebrae

Question 17

Where does C8 spinal nerve emerge

Answer 17

Between vertebrae of C7 and T1

Question 18

Where do T1-L5 spinal nerves emerge

Answer 18

Below their corresponding vertebrae

Question 19

Where do S1-4 spinal nerves emerge

Answer 19

Via 4 pairs of sacral foramina

Question 20

Where do S5 and Co1 spinal nerves emerge

Answer 20

Via sacral hiatus

Question 21

What do spinal nerves divide into

Answer 21

Posterior and anterior rami

Meningeal branch

Question 22

What does the posterior rami supply

Answer 22

Deep muscles and skin of dorsal trunk

Question 23

What does the anterior rami supply

Answer 23

Muscles and skin of limbs, lateral trunk and ventral trunk

Question 24

Course of meningeal branch of spinal nerves

Answer 24

Re-enters spinal canal through intervertebral foramina

Question 25

What do the meningeal branches of spinal nerves supply

Answer 25

Vertebrae Ligaments BVs Meninges

Question 26

What's an axial line

Answer 26

Junction between 2 adjacent dermatomes that are supplied from discontinuous spinal levels

Question 27

What axial lines do limbs have

Answer 27

Anterior and posterior

Question 28

What do axial lines mark

Answer 28

Centre of either the pre-axial or post-axial compartments of limbs

Question 29

What are the boundaries of pre and post axial compartments marked by

Answer 29

Veins

Question 30

Definition of dermatome

Answer 30

Strip of skin supplied by a single spinal nerve that can be examined clinically

Question 31

Definition of myotome

Answer 31

Group of muscles innervated by a single spinal nerve that can be examined clinically

Question 32

What is a peripheral nerve territory

Answer 32

Area of skin supplied by a single peripheral nerve | Within a peripheral nerve there may be fibres from more than 1 spinal nerve

Question 33

What's the scientific name for shingles

Answer 33

Herpes zoster

Question 34

Why does herpes zoster affect one dermatome

Answer 34

Chickenpox virus travels through a cutaneous nerve and remains dormant in a dorsal root ganglion When host is immunosuppressed, the virus reactivates and travels through a peripheral nerve to the skin of a single dermatome

Question 35

What forms the sclerotome

Answer 35

Ventral surface of somites

Question 36

What is the neural level of injury

Answer 36

Lowest level of full sensation and function

Question 37

Spinal roots responsible for lateral rotation of shoulder

Answer 37

C5

Question 38

Spinal roots responsible for medial rotation of shoulder

Answer 38

C6-8

Question 39

Spinal roots responsible for Flexion at shoulder

Answer 39

C5

Question 40

Spinal roots responsible for extension at shoulder

Answer 40

C6-8

Question 41

Spinal roots responsible for abduction at shoulder

Answer 41

C5

Question 42

Spinal roots responsible for adduction at shoulder

Answer 42

C6-8

Question 43

Spinal roots responsible for supination

Answer 43

C6

Question 44

Spinal roots responsible for pronation

Answer 44

C7-8

Question 45

Spinal roots responsible for Flexion at elbow

Answer 45

C5-6

Question 46

Spinal roots responsible for extension at elbow

Answer 46

C6-7

Question 47

Spinal roots responsible for Flexion at wrist

Answer 47

C6-7

Question 48

Spinal roots responsible for extension at wrist

Answer 48

C7-8

Question 49

Spinal roots responsible for abduction and adduction of digits

Answer 49

T1

Question 50

Spinal roots responsible for extension of fingers

Answer 50

C7-8

Question 51

Spinal roots responsible for Flexion of fingers

Answer 51

C6-8

Question 52

Spinal roots responsible for lateral rotation at hip

Answer 52

L5 and S1

Question 53

Spinal roots responsible for medial rotation at hip

Answer 53

L1-3

Question 54

Spinal roots responsible for adduction at hip

Answer 54

L1-3

Question 55

Spinal roots responsible for abduction at hip

Answer 55

L5 and S1

Question 56

Spinal roots responsible for Flexion at hip

Answer 56

L2-3

Question 57

Spinal roots responsible for extension at hip

Answer 57

L4-5

Question 58

Spinal roots responsible for Flexion at knee

Answer 58

L5 and S1

Question 59

Spinal roots responsible for extension at knee

Answer 59

L3-4

Question 60

Spinal roots responsible for dorsiflexion

Answer 60

L4-5 | L5 and S1 for metatarsophalangeal and interphalangeal joints

Question 61

Spinal roots responsible for plantarflexion

Answer 61

S1-2

Question 62

Spinal roots responsible for eversion

Answer 62

L5 and S1

Question 63

Spinal roots responsible for inversion

Answer 63

L4-5