OSCE practise

Question 1

1. What are different types of arterial diseases?
2. What is the main pathology?
3. What are the risk factors?

Answer 1

1. PAD, atherosclerosis, acute limb ischaemia, buerger’s disease
2. narrowing or blockage of arteries -> reduced oxygenated blood to tissue
3. smoking, diabetes, hypertension, hyperlipidaemia, age, family history

Question 2

What findings would you find in arterial diseases regarding the following:

1. pain
2. pulses
3. skin
4. ulcers
5. colour

Answer 2

1. intermittent claudication (pain on walking, relieved by rest) -> may progress to rest pain
2. weak or absent distal pulses
3. cool, pale, hair loss, thin skin
4. “punched-out” edges, often over pressure points (toe, lateral malleolus)
5. pallor on elevation

Question 3

Why is PAD worse at night sometimes? What would this indicate?

Answer 3

When you’re upright during the day, gravity helps pull blood down into your legs, so even with narrowed arteries, some flow still makes it through.

At night, lying flat removes that help — your legs are at heart level, so the already low perfusion pressure in PAD drops even more.

muscle tissues hurting at rest because of low oxygen supply

Question 4

What would indicate mild PAD?

What would indicate severe PAD?

Answer 4

mild: only claudication (pain on walking) - stenosed arteries cant dilate enough to meet the higher demand

severe: rest pain, especially at night = red flag for critical limb ischaemia

Question 5

1. What are examples of venous diseases?
2. What is the main pathophysiology?
3. What are risk factors?

Answer 5

• chronic venous insufficiency
• varicose veins
• DVT
• post-thrombotic syndrome

2. impaired venous return -> blood pooling in veins -> increased venous pressure
3. prolonged standing, obesity, DVT history, age and family history

Question 6

What is the difference in the images?

Answer 6

left: venous ulcer
- varicose veins, previous DVT, obesity
- usually between lower calf and medial malleolus
- shallow and flat margins, mod to heavy exudate, slough at base with granulation tissue
- treated with compression therapy, leg elevation, surgical management

right: arterial ulcer
- diabetes, htn, smoking, previous vascular disease
- pressure points, toes and feet, lateral malleolus and tibial areas
- punched out and deep, irregular shape, unhealthy wound bed, necrotic tissue, minimal exudate unless infected
- treated with revascularisation, anti-platelet medication, manage risk factors

Question 7

A 58-year-old smoker develops calf pain after walking 200 m, which resolves after resting for 5 minutes. On exam, dorsalis pedis pulse is weak.

What is the most likely diagnosis and pathophysiology?

Answer 7

PAD due to atherosclerotic narrowing of leg arteries, causing reduced oxygen supply during exercise → intermittent claudication.

Question 8

A 70-year-old man with atrial fibrillation presents with sudden-onset severe left leg pain, pallor, and absent distal pulses.

What is the most likely cause?

Answer 8

Arterial embolism (often from left atrium in AF) causing acute arterial occlusion — “6 P’s”: pain, pallor, pulselessness, paresthesia, paralysis, poikilothermia

Question 9

A 64-year-old woman with PAD has a painful ulcer on her lateral malleolus. The ulcer has a “punched-out” edge, pale base, and minimal exudate.

What type of ulcer is this and why is it painful?

Answer 9

arterial ulcer — due to ischaemia; pain worsens with elevation because gravity no longer assists perfusion

Question 10

A 55-year-old man with varicose veins complains of ankle swelling and dull aching after standing all day. Brownish skin changes are seen above the medial malleolus.

What is the underlying mechanism?

Answer 10

incompetent venous valves cause venous hypertension → capillary leakage → hemosiderin deposition and oedema

Question 11

A 62-year-old woman has a shallow, exudative ulcer above the medial malleolus with surrounding hyperpigmentation.

What is the most likely diagnosis and key difference from arterial ulcer?

Answer 11

venous ulcer - occurs with venous hypertension, usually less painful, with more exudate and irregular edges, compared to the dry, punched-out arterial ulcer

Question 12

Which bedside test assesses ulnar artery patency before radial artery cannulation?

Answer 12

modified allen test

Question 13

Which test distinguishes superficial from deep venous valve incompetence?

Answer 13

trendelenburg

Question 14

Which test involves elevating the leg to 45° to assess for pallor and reactive hyperaemia?

Answer 14

buerger’s test