Session 2: Myotomes

Question 1

Define myotome.

Answer 1

A group of muscles supplied by a single spinal nerve.

Question 2

Define motor unit.

Answer 2

A motor neurone and the skeletal muscle fibres that the motor neurone innervates.

Question 3

Movements of: C5

Answer 3

Shoulder abduction and external rotation.

Question 4

Movements of: C6

Answer 4

Elbow flexion, wrist extension and supination.

Question 5

Movements of: C7

Answer 5

Elbow extension, wrist flexion and pronation. Basically the opposite of C6!

Question 6

Movements of: C8

Answer 6

Finger flexion and finger extension.

Question 7

Movements of: T1

Answer 7

Finger abduction and adduction.

Question 8

Movements of: L2

Answer 8

Hip flexion.

Question 9

Movements of: L3

Answer 9

Knee extension

Question 10

Movements of: L4

Answer 10

Ankle dorsiflexion

Question 11

Movements of: L5

Answer 11

Great toe extension

Question 12

Movements of: S1

Answer 12

Ankle plantar-flexion

Question 13

Movements of: S2

Answer 13

Great to flexion

Question 14

What is Hilton’s law?

Answer 14

The nerves supplying the joint capsule also supply the muscles that move the joint and the skin overlying the insertions of the muscles.

Question 15

Define neural level.

Answer 15

The lowest level of fully intact sensation and motor function.

Question 16

If you have a patient with femoral nerve injury in the inguinal region (groin). Where will the patient have anaesthesia most likely?

Answer 16

In the cutaneous distribution of the femoral nerve. (Anterior femoral cutaneous nerve and the saphenous branch).

Question 17

If you have a patient with femoral nerve injury in the inguinal region (groin).
Where will the patient have paralysis most likely?

Answer 17

In the muscles that are supply by the femoral nerve distal to the site of injury. This means that any muscles supplied proximally to the injury will be spared.