Limb Circulation

Question 1

Describe the fate of the femoral artery

Answer 1

The femoral artery runs through the adductor hiatus to the back of the leg and becomes the popliteal artery. It then splits into anterior tibial artery and posterior tibial artery

Question 2

What artery supplies the muscles of the back of the thigh?

Answer 2

Deep artery of thigh

Question 3

Where does the hip joint circulation come from?

Answer 3

The medial and lateral circumflex branches which are from the deep artery of thigh.

Question 4

What is the role of the obturator artery?

Answer 4

This is a continuation of internal iliac, and it assists the deep artery of thigh to supply the adductor muscles.

Question 5

Where is the femoral pulse found?

Answer 5

At the midpoint between ASIS and the pubic symphysis, inferior to the inguinal ligament.

Question 6

What is the blood supply to the knee joint?

Answer 6

The genicular arteries. There are four, superior medial and lateral and inferior medial and lateral.

Question 7

Why is it necessary for arteries to anastomoses around the knee joint?

Answer 7

To ensure that blood supply to the lower limb is maintained in both flexion and extension.

Question 8

What is the origin of the Dorsalis pedis artery?

Answer 8

This is a branch of the popliteal artery which passes through the interosseous membrane to the front of the leg. It then continues down the front of the leg, onto the dorsum of the foot.

Question 9

What is intermittent claudication?

Answer 9

This is where there is pain on walking/exercise, relieved by rest and is usually due to atheromatous plaque which leads to limited blood supply and ischaemia to muscles of the legs.

Question 10

What is ankle-brachial pressure index?

Answer 10

This is taken with the patient lying down and is calculated leg/arm. Normal range is 0.9-1.2.

Question 11

Why is occlusion of blood vessels so clinically important?

Answer 11

If radius decreases by 1/2, then this means flow rate will decrease by 1/16 because flow is proportional to r^4.

Question 12

Name some signs of peripheral arterial disease.

Answer 12

Lack of hair, skin problems, ulcers, infection, skin necrosis, loss of pulses, cold to touch.

Question 13

When can ischaemia happen in the leg?

Answer 13

Atheromatous plaque and thrombus formation, or also because of swelling/inflammation or bleeding within a tight fascial compartment leading to increased pressure.

Question 14

What is the cause of a palpable pulsating mass in the popliteal fossa?

Answer 14

Popliteal aneurysm.

Question 15

When is the popliteal artery at risk of rupture?

Answer 15

Distal fracture of the femur or dislocation of the knee.

Question 16

What is saphenous cut down?

Answer 16

If struggling to canulate then can use this method. Saphenous vein is fairly deep. Risk of damage to saphenous nerve, and therefore loss of sensation on medial border of the foot.

Question 17

Name two ways in which blood flow in the legs is assisted.

Answer 17

Venae comitantes, pumping action of the calf muscles.

Question 18

When do varicose veins occur?

Answer 18

When the valves don’t meet. This can cause the veins to become engrossed.

Question 19

What can venous insufficiency in the leg cause?

Answer 19

Stasis of blood and ulcers on the medial aspect of the leg

Question 20

Name three factors which can lead to DVT

Answer 20

Stasis of blood, hypercoaguability and vascular damage.

Question 21

How will a person with a DVT present?

Answer 21

Warm, swollen calf and erythema of the affected limb.