Myotomes and dermatomes

Question 1

Important dermatomes

Answer 1

Upper limb

C5- anterior stops at wrist. in between T1 and C6
C6- outside of arm
C7- posterior arm
C8- inside ulnar part of arm
T1- Inside arm and across chest in corresponding rib section.

Question 2

C5 myotome

Answer 2

Deltoids

Question 3

C6 myotome

Answer 3

wrist extensors

Question 4

C7 myotome

Answer 4

Elbow extensors

Question 5

C8 myotome

Answer 5

Long finger flexors

Question 6

T1 myotome

Answer 6

Small hand muscles

Question 7

L2 myotome

Answer 7

Hip flexor

Question 8

L,3 myotome

Answer 8

Knee extensors

Question 9

L4-5 (s1 hamstrings) myotome

Answer 9

Knee flexion, ankle dorsiflexion

Question 10

L5 myotome

Answer 10

ankle dorsiflexors and long toe extensors

Question 11

S1 myotome

Answer 11

Ankle plantar flexion

Question 12

ASIA classification

Answer 12

A- complete: no motor or sensory preserved in sacral segments.
B- Incomplete: sensory, no motor function in sacral
C- Incomplete- lower than 3 power graded
D- Incomplete- higher than 3 graded.

Question 13

Central cord syndrome

Answer 13

flaccid weakness of arms> legs

Some lower extremity movement and sensation preserved

Question 14

Anterior cord syndrom

Answer 14

Loss of motor

Decreased pain and sensation below lesion

Question 15

Posterior cord syndrom

Answer 15

Proprioception affected- ataxia

usually good power and sensation

Question 16

Brow-Sequard Syndrome

Answer 16

Half of spinal cord injured

Paralysis on affected side

Pain and temp loss on opposite side.

Question 17

Cauda Equina syndrome

Answer 17

Back pain

Bowel and bladder dysfunction
Leg numbness and weakness