Anatomy - Leg circulation

Question 1

What are the two different types of fascia ?

Answer 1

Superficial and deep

Question 2

What is fascia lata ?

Answer 2

Deep fascia of the thigh

Question 3

What does deep fascia form ?

Answer 3

Forms compartments separated by intermuscular speta which is deep fascia that separates two muscles

Question 4

Describe the main overview of the arterial blood supply of the upper limb down to the anastomoses in the hand

Answer 4

Subclavian ===> Axillary ====> Brachial ===> Branches into radial (more lateral one) and ulner (more medial one) ===> deep and superficial plamar arches

Question 5

What artery predominatley forms the superficial palmar arch and what artery also contributes ?

Answer 5

Predominatley formed by the ulner artery with a contribution from the superficial palmar branch of the radial artery.

Question 6

What arteries is the deep palmar arch formed by?

Answer 6

Formed mainly from the terminal part of the radial artery, with the ulnar artery contributing via its deep palmar branch, by an anastomosis.

Question 7

Describe the vneous draing of the upper limb

Answer 7

Cephalic (more lateral) and basilic (more medial) veins drain to ====> axillary vein ====>

R subclavian vein

Question 8

What is the vein which runs horizontal between the cephalic and basilic veins ?

Answer 8

The median cubital vein

Question 9

Describe the arterial supply of the lower limb

Answer 9

Femoral (which has a deep branch off it called the profunda femoris) =====> popliteal ====> Branches into the posterior and anterior tibial arteries

Anterior tibial ===> dorsalis pedis ===> arcuate artery (dorsum of foot)

Posterior tibial artery (has a branch come off it called the fibular artery) ===> Branches into the medial and lateral plantar arteries

Lateral plantar artery ===> plantar arch (sole of foot)

Question 10

At what anatomical location does the femoral artery pass through and then become the popliteal artery ?

Answer 10

The adductor hiatus

Question 11

Describe the venous drainage of the lower limb

Answer 11

Small saphenous ====> Popliteal vein ====> femoral vein

Great saphenous vein ===> femoral vein

Question 12

Roughly in what region does the great saphenous vein join onto the femoral vein ?

Answer 12

The inguinal region

Question 13

Roughly where does the popliteal vein become the femoral vein ?

Answer 13

As it passes through the adductor hiatus

Question 14

Describe the route of the small saphenous vein

Answer 14

Arises from the dorsal venous arch ===> goes behind the lateral malleolus and then runs up the back of the calf drainging into the popliteal vein (posterior to the knee)

Question 15

Describe the route of the great saphenous vein

Answer 15

Arsies from the dorsal venous arch ===> runs in front of the medal malleolus and then rises up the mdial side of the upper leg to join with femoral vein roughly at the inguinal region (around the femoral triangle)

Question 16

Describe venous blood flow

Answer 16

• Musculovenous pump pushes blood back towards the heart
• Flow from superficial veins into deep veins through perforating veins

Question 17

What is the function of valves in terms of venous blood flow and what can happen if valves become incompetent ?

Answer 17

Venous valves ensure unidirectional blood flow against gravity (prevent back flow)

• When valves become incompetent it results in reverse flow into superficial veins.
• These veins become weak and dilated
• Resulting in Varicose veins

Question 18

Clinical note

Answer 18

CLINICAL NOTE

• Digital arteries are end arteries
• The ONLY blood supply to a given area of the body (no collaterals)
• Untreated occlusion of an end artery results in infarction of the area of tissue it supplies resulting in amputation
• Do not use adrenaline-containing local anaesthetic near end arteries

Question 19

What are the main pulse points in the body ?

Answer 19

• Carotid
• In the upper limb - brachial and radial
• In the lower limb - Femoral, popliteal, posterior tibial and dorsalis pedis

Question 20

Define what is meant by ischaemia

Answer 20

Inadequate oxygenation of cells/tissues/organ due to an interruption to blood supply (arterial or venous)

Question 21

What are the two main overall causes of Ischaemia ?

Answer 21

• Reduced arterial perfusion pressure
• Increased venous drainage pressure

Question 22

What are some of the causes of reduced arterial perfusion pressure ?

Answer 22

• Left ventricular failure
• Arterial bleed (injury)
• Arterial rupture (aneurysm)
• Occlusion of lumen (atherosclerosis: PVD)
• Arterial spasm
• External compression of arterial supply (e.g. tumour/compartment syndrome/crossing legs!!/inflammation/ tamponade)

Question 23

What are some of the causes of increased venous drainage pressure ?

(back pressure into capillary bed then into the arteriole…preventing normal arterial in-flow)

Answer 23

• Right (or congestive) cardiac failure
• DVT
• External compression (e.g. tumour)

Question 24

Describe the pathway of skin ulceration formation (overview not as specific as the other flashcard)

Answer 24

1. Venous valve failure of any cause or immobility of any cause
2. Resulting in (chronic) venous insufficiency (venous blood not efficiently returned to heart)
3. Resulting in superficial microcirculatory deficiencies
4. Then skin ulceration formation

Note after step 2 it can go either the skin ulceration pathway or DVT pathway

Question 25

Describe the pathway of DVT formation

Answer 25

1. Venous valve failure of any cause or immobility of any cause
2. Resulting in (chronic) venous insufficiency (venous blood not efficiently returned to heart)
3. Deep venous stasis
4. Thrombosis/embolism formation

Note again after stage 2 it can either go DVT pathway or skin ulceration pathway

Question 26

Describe venous ulceration formation

Answer 26

• Venous pressure increases
• Damages blood vessels in skin
• Skin becomes dry, itchy and inflamed
• Cannot heal well due to poor blood supply
• Begins to break down

Question 27

What is the most common site of venous ulceration formation ?

Answer 27

The “gaiter area” - medial aspect distal leg

Question 28

What are the important lymph nodes in the upper limb ?

Answer 28

Cubital and axillary lymph nodes

Question 29

Generally what does the path of lymphatics follow ?

Answer 29

The pathway of veins

Question 30

What is the flow of lymphatics in the lower limb ?

Answer 30

Popliteal nodes ===> Superficial and deep inguinal lymph nodes