The Musculotaneous Nerve

Question 1

Muscles Innervated

Answer 1

BBC = Biceps, Brachialis, Coracobrachialis

Question 2

Motor Functions

Answer 2

Flexion of the arm at the elbow, supination of the forearm

Question 3

Sensory

Answer 3

Lateral Surface of forearm through the lateral antebrachial cutaneous nerve

Question 4

What muscle does the MCN travel through?

Answer 4

Coracobrachialis

Question 5

MOTOR (i.e. motor to the muscles of the anterior upper arm).

Answer 5

• Coracobrachialis
• Biceps Brachii
• Brachialis

Question 6

SENSORY

Answer 6

• Lateral forearm

Question 7

Causes of Musculocutaneous nerve lesions: name 5?

Answer 7

• Very rarely damaged
• Most common upper limb nerve affected by diabetic neuropathy.
• Direct trauma: proximal humeral fracture, gunshot wounds, shoulder dislocation
• Rapid extension of forearm
• Entrapment in coracobrachialis

Question 8

Injury to the musculocutaneous nerve may lead to:

Answer 8

Weakness in elbow flexion, supination, loss of biceps DTR, sensory deficits and/or pain over lateral forearm