Clinical Correlates

Question 1

What is the pathway for referred pain from the heart to the medial side of the arm? Why?

Answer 1

1. Medial brachial cutaneous nerve supplies sensation to the skin on the medial side of the proximal arm. Often, there is communication between this nerve and the intercostobrachial nerve (lateral cutaneous branch) from the second intercostal space.
2. T1-2 spinal cord segments receives afferent input from both the heart and the skin of the medial arm.

(Heart pain is more commonly referred to the left arm but may be referred to the right arm.)

Question 2

Due to collateral circulation of the elbow, where is it safe to surgically clamp the main artery of the upper extremity (subclavian, axillary, brachial)?

Answer 2

distal to the profunda brachii artery

(if it were clamped more distally, hypoxia would ensue)

Question 3

The ulnar nerve passes _____ , where it is vulnerable to being bumped or injured in a fracture.

Answer 3

posterior to the medial epicondyle

Question 4

Define pronator teres syndrome.

Answer 4

Median nerve becomes entrapped by hypertrophy, inflammation or fibrosis of the pronator teres muscle.

(sometimes the deep head of pronator teres is missing)

Question 5

A 24 year-old female presents at the ED w/a mid-shaft humeral fracture. What deficits do you expect to see? Which nerve is most likely damaged?

Answer 5

• Wrist drop (inability to extend the wrist)
• radial nerve

(she will still be able to extend the elbow after the fracture heals because there are branches that go to the medial and long head of the triceps before it enters the radial groove)

Question 6

Why would the palmaris longus tendon be electively removed during surgery?

Answer 6

For use in transplants.

Question 7

What is the presentation for cubital tunnel syndrome?

Answer 7

• Weak and a grip
• Weekend wrist flexion and adduction
• Paraesthesia
• Numbness along the medial side of the hand and medial 1 1/2 fingers

Question 8

Define the cubital tunnel.

Answer 8

A space between the humeral and ulnar heads of flexor carpi ulnaris.

(The ulnar nerve runs through the cubital tunnel and maybe come and trapped here close parentheses.)

Question 9

Define Tenosynovitis.

Answer 9

Synovial sheath inflammation.

Question 10

What are the signs and symptoms of tenosynovitis?

Answer 10

• edema
• pain
• compressression of adjacent structures (nerves)

(chronic inflammation can lead to a tendon rupture. Tendon rupture may also occur following a course of antibiotics such as fluoroquinolones/Levaquin)

Question 11

Define anterior interosseous syndrome.

Answer 11

Entrapment of the anterior interosseous nerve.

Question 12

What are the signs and symptoms of anterior interosseous syndrome?

Answer 12

• Weekend pronation
• Inability to flex:

1. dip joints Fingers 2 and 3
2. Inability to flex: Interphalangeal joint of thumb

Question 13

Define volkmann’s ischemic contracture.

Answer 13

Flexor compartment syndrome of the forearm.

Question 14

What are examples of causes of Volkmann’s ischemic contracture?

Answer 14

Traumatic injuries to collateral circulation of the elbow.

(ligation during surgery needs to happen after branching of the profunda brachii a. in order to avoid ischemic necrosis of the extremity)