Loco1

Question 1

1. Which nerve is most at risk of damage from a mid-shaft humeral fracture? (1 mark) Which movements of the limb are bought about from the muscle compartments it supplies? (2 marks)

Answer 1

Radial nerve (1 mark)

Elbow extension (1 mark)

Wrist and finger extension (1 mark)

Award 1 out of 2 for just stating ‘extension’

Question 2

1. Name the FOUR main pulse points of the upper limb and a brief description of where you would palpate them (4 marks)

Answer 2

Axillary – in the armpit

Brachial – either medial to biceps brachii in the mid-arm or in the cubital fossa

Radial – lateral to flexor carpi radialis tendon or on the lateral aspect of the anterior forearm (in anatomical snuffbox could also be acceptable)

Ulnar – medial aspect of the wrist or by the ulnar styloid process

½ mark for pulse point and ½ mark for location

Question 3

1. Name TWO common causes of compartment syndrome (1 mark)

Answer 3

Any two from (½ mark each): Trauma.(Fractures of the midshaft radius and/or ulna, distal radius fractures, or supracondylar humerus fractures, crush injuries, contusions, gunshot wounds to the forearm).
Tight casts, dressings, or external wrappings, extravasation of intravenous fluids/infusions, burns, bleeding disorders, post-ischemic swelling, arterial injuries, intensive use of muscles during exercise, seizures, eclampsia, tetany,

intravenous drug administration, anticoagulation therapy increases the risk of compartment syndrome in patients who sustain an injury to their forearm

rare causes such as snake bites or carbon monoxide intoxication

Question 4

1. What name is given to the procedure carried out to enable decompression of a limb with compartment syndrome? (1 mark) Why is there a delay in closing the wound after surgical intervention? (1 mark)

Answer 4

Fasciotomy (1 mark). The delay in closing the wound allows for debridement of tissue to occur if required and allows for further decompression (1 mark for either answer)

Question 5

define compartment syndrome

Answer 5

1. Compartment syndrome is a pathological condition characterised by elevated interstitial pressure in a closed osteofascial compartment that results in microvascular compromise (restriction of capillary blood flow).[1]

Question 6

where does compartment syndrome commonly occur?

Answer 6

1. Most commonly in the anterior compartment of the forearm:
2. deep posterior or anterior compartment of the leg

Question 7

what are the two types of comparment sydrome?

what causes each

Answer 7

1. Acute compartment syndrome
   
   1. Sudden, usually after a fracture or severe injury
   2. Burns
   3. Compression support (application of tight casts / dressings)
   4. Surgery to repair a damaged or blocked blood vessel
   5. Anabolic steroid use
2. Chronic compartment syndrome
   
   1. Regular repetitive exercise
   2. Progressively worsens as you exercise but can stop completely after 15mins of stopping activity
   3. Unknown cause

Question 8

explain pathophysilogy of CS

Answer 8

1. Pathophysiology:
   
   1. Due to fascia not stretching, when trauma, oedema or haemorrhage occurs within the compartment, it can lead to increased pressure to above the capillary level, which restricts capillary inflow.
      
      1. Causes ischemia.
      2. This results in tissue & muscle necrosis
   2. As pressure increases, veins become compressed: increasing hydrostatic pressure in the veins.
      
      1. Causes fluid to move out of vein into compartment
      2. Increases intra-compartmental pressure even more
   3. Traversing nerves are compressed
      
      1. Sensory and or motor deficit in the distal distribution
   4. Irreversible muscle and nerve damage after 8 hours

Question 9

what do u need to monitor for after treating CS?

Answer 9

1. Monitor for reperfusion injury (sudden delivery of oxygen to muscle after sudden ischemia)
   
   1. Toxins come out that region into body
   2. Oxygen going into area can trigger stress response

Question 10

What is the carpal tunnel? What is contained within it? (you’re looking for 10 items you might want to draw a simple diagram to help)

Answer 10

The carpal tunnel is created by a thick band of retinacula spanning between the carpal bones of the wrist, creating a tunnel. Passing through this tunnel are the tendons of

• Flexor digitorum superficialis (4)
• Flexor digitorum profundus (4)
• Flexor pollicis longus (1)
• And the Median nerve

Question 11

What causes the symptoms of carpal tunnel syndrome?

Answer 11

Swelling of the tendons can compress the median nerve, leading to a median nerve palsy

Question 12

Two muscles that are affected by carpal tunnel syndrome are the abductor pollicis brevis and the opponens pollicis. How would you test their function?

Answer 12

Abduction of the thumb, and opposition of the thumb.