LE Dermatomes, Myotomes, and Reflexes

Question 1

hip flexion myotome

Answer 1

L1, L2

Question 2

knee extension myotome

Answer 2

L3, L4

Question 3

ankle dorsiflexion myotome

Answer 3

L4, L5

Question 4

great toe extension

Answer 4

L5

Question 5

Bowel/bladder myotome

Answer 5

S2-S4

Question 6

inguinal area dermatome

Answer 6

L1

Question 7

anterior mid-thigh dermatome

Answer 7

L2

Question 8

Distal anterior thigh and medial knee dermatome

Answer 8

L3

Question 9

medial lower leg and foot dermatome

Answer 9

L4

Question 10

Lateral lower leg and foot dermatome

Answer 10

L5

Question 11

posterior calf dermatome

Answer 11

S1

Question 12

medial calcaneus dermatome

Answer 12

S2

Question 13

ankle eversion myotome

Answer 13

S1, S2

Question 14

Ankle plantarflexion myotome

Answer 14

S1, S2

Question 15

Achille’s reflex

Answer 15

S1, S2

Question 16

Patellar reflex

Answer 16

L2-L4

Question 17

Posterior tibial reflex

Answer 17

L5

Question 18

Heel walking

Answer 18

L5

Question 19

Toe walking

Answer 19

S1

Question 20

What are the grades for reflexes and what do they mean?

Answer 20

4+ : hyper-reflexive and indicative of upper motor neuron dysfunction or myelopathy
3+ : Reflex in upper half of normal
2+ : Refles in lower half of normal
1+ : present but diminished either as compared to the other side or as compared to normal
0 : absent