MSK

Question 1

What occurs with long thoracic nerve injury?

Answer 1

Winging of the scapula as it innervates serratus anterior.

Question 2

What occurs with axillary nerve injury?

Answer 2

Loss of shoulder abduction past 15 degrees and weakened external rotation. Prone to injury with fracture of surgical neck of humerus

Question 3

What does the radial nerve innervate?

Answer 3

Triceps brachii, extensor compartment of forearm, brachioradialis and supinator.

Question 4

What can occur with radial nerve injury?

Answer 4

Wrist drop and loss of sensation over the thumb. Prone to injury with midshaft fracture of humerus and compression with crutches

Question 5

What does the musculocutaneous nerve innervate?

Answer 5

Flexors of the arm: Coracobrachialis, brachialis and biceps brachii.
Cutaneous sensation to skin of lateral forearm.

Question 6

What occurs with injury to the musculocutaneous nerve?

Answer 6

Loss of elbow flexion

Question 7

What does the ulnar nerve innervate?

Answer 7

• Motor innervation to flexor carpi ulnaris, ulnar half of flexor digitorum profundus, hypothenar muscles and intrinsic muscles of hand except medial two lumbricals.
• Cutaneous innervation to medial 1/3rd of hand.

Question 8

What occurs with ulnar nerve injury?

Answer 8

• With entrapment it can result in tardy ulnar palsy which will cause loss of cutaneous sensation and loss of fine motor control of the hand.
• With fracture of medial epicondyle of humerus it will result in claw hand

Question 9

What is claw hand?

Answer 9

Occurs with ulnar nerve injury. There is hyperextension at the metacarpal-phalangeal joint and hyperflexion of the interphalangeal joints. This is the appearance of the hand at rest.

Question 10

What is APE hand?

Answer 10

• Sign of low median nerve injury.
• Thenar muscles are paralysed so the thumb lays in the same plane as the other digits at rest. This is because the adductor pollicis is innervated by the ulnar nerve.

Question 11

What is the sign of benediction?

Answer 11

• Occurs with a high median nerve injury.
• It is an active deformity, meaning when you ask a person to form a fist, only the 4th and 5th digit flex. The first 3 digits cannot flex.

Question 12

What does the median nerve innervate?

Answer 12

• Flexor compartment of the forearm except those supplied by ulnar nerve,
• Thenar muscles and medial two lumbricals.

Question 13

What occurs with median nerve entrapment/inflammation.

Answer 13

Carpal tunnel syndrome. Symptoms include:

• Pain and paraesthesia or the thumb, 2nd and 3rd digits.
• Atrophy of thenar muscles and decreased movement of the thumb.