Dermatomes & Myotomes UL

Question 1

Define dermatome & myotome

Answer 1

Dermatome: Area of skin supplied by a single spinal nerve
Myotome: Muscles supplied by a single spinal nerve

Question 2

Myotomes of Upper limb

Answer 2

C5: (hug) Shoulder abduction, external rotation, (elbow flexion)

C6: (idk) Elbow flexion, wrist extension, supination, (internal rotation of shoulder)

C7: (zombie) Elbow extension, wrist flexion, pronation, finger flexion, extension)

C8: (hi) finger flexion, extension, thumb extension, wrist ulnar deviation

T1: (alien) finger abduction, adduction

Question 3

How can axons form within a single spinal nerve enter multiple peripheral nerves via the brachial plexus

Question 4

How may a peripheral nerve obtain axons from multiple spinal nerves via the brachial plexus

Question 5

At the divisions what do the anterior and posterior supply?

Answer 5

Anterior: Flexors
Posterior: Extensors

Question 6

Where will the reassortment of fibres for the distribution to limb compartments occur

Answer 6

At the level of cords
e.g.) The axillary and radial nerves run posteriorly to supply the extensors

Question 7

The no. of spinal nerves contributing to a terminal branch is proportional to…

Answer 7

the no. of joints that the muscle it supplies act upon