Anatomy - Vascular anatomy of the limbs Flashcards
describe the arteries
- Carry blood away from the heart
- Branch, divereg and fork as they form smaller vessels
- Highest pressure is in the arteries
describe the veins
- Carry blood towards the heart
- Join, merge and convereg into larger vessels
what happens to the pressure between the arteries and the vena cava
- it decreases
- Arteries have the highest pressure
- Vena cava has the lowest blood pressure
how much blood volume is in the material and Venus systems
- 20% in arteries
- 80% in veins (large diameter and ability to expand)
describe the subclavian artery
Subclavian arises from the aorta
- Suppies upper limb
- Goes underneath the clavicle
where does the axillary artery start and end
- Continuation of subclavain arteries
- Starts at lateral border of the 1st rib, it is sandwiched between the first rib and the clavicale on top
- Ends at lateral border of teres major (m) this is a muscle in the back it travels from the back of the scapula across the humerus
where does the axillary artery run through
- Runs through the axilla – armpit
- Branches to chest wall and shoulder girdle – this is where the humeral circumflex is, it goes round the neck of the humerous and supplies the humerus itself
what are the three parts that the axillary artery is divided in to
- 1 = enclosed in axillary sheath lateral border of 1st rib and medial border of pectoralis minor
- 2 = posterior to pectoralis minor
- 3 = lateral border of pectolaris minor and inferior border of teres major
where does the brachial artery start and end
- starts at lateral border of teres major (m) this is a muscle in the back it travels from the back of the scapula across the humerus
- Ends 1cm below the elbow
- continuation of the axillary artery
what does the brachial after divide into
- It has one major branch this is called the profunda brachii (deep artery of the arm)
where is the brachial pulse
this medial to the distal tendon of biceps brachii
what does the brachial artery run through
- Branchial artery runs superficial on the antieror medial side
what does the profounda branch of the brachii run through and supply
- this runs down the posterior side and supplies the triceps
- The profunda brachii (branch of the bracial artery)accompanies the radial nerve on the posterior side of the arm
what is collateral circulation in the brachial artery
- Some structures reconnect with the ulnar artery and some connect with the radial artery and this allows for a colleatral circulation, allows circulation if there is block to the arteries
where does the ulnar artery run and what does it supply
- Ulnar arter runs down the medial aspect of the forearm and is more deeper and supplies medial muscles of the foremarm
what is bigger the ulnar artery or the radial artery
The ulnar is the bigger of the two branches, it further subdivides this is why it is bigger
what does the ulnar branch into
- The ulnar a has One branch – commmon interosseous supplies deep flexors and extensors of the forearm, it goes through the interosseous membrane between the radiusa and the ulnar so there is a blood supply to the back fo the forearm
describe where the radial artery goes and what it supplies
- Radial runs down the lateral asepct of the foremar and supplies the lateral muscles of the forearm mainly in the anterior compartment
what do the radial and ulnar arteries form when they anastomise
form the deep and superifical palmer arches
what do the palmer arteries have
- they both have contributions from the radial and ulnar arteries, this means that one of the palmer arches can always supply the heart either the superficial or deep palmer arches
what are the two palmer arches
deep and superficial
describe the superficial arch
- mainly receives blood from the ulnar artery
- curves across palm at level of distal border of extended thumb
describe the deep arch
- Deep arch from the radial artery
= lies across metacarpal at their bases
where is the radial pulse
lateral to the tendon of the FCR
where is the ulnar pulse
lateral to tendon of FCU, more difficult to palpate because it runs deeper and lies under the pisiform and the palmar fascia
describe how to do the Allens test
- Step 1 the hand is exsanguinated by making a fist and digital pressure on both radial and ulnar arteries at the distal end of forearm
- Step 2 patient opens hand (hand should be pale) pressure released of either radial or ulnar arteries individually and capillary refill of entire hand indicates patent artery and palmar arches
- Normal filling time <5 seconds
- If it stays white then there is no collarteral circulation and there is an interruption of the circulation of blood flow
what does the Allens test measure
collateral circulation
describe deep drainage
- deep veins are inside the fascia compartment
- they have the same name as the artery
- there is usually two deep veins for each artery for example there are two brachial veins and they lie on either side of the artery
- drain from inside the fascia compartment
what are the two superficial veins in the upper limb
basilica vein
cephalic vein
what joins the cephalic and basilica vein
- Median cubital vein across the cubital fossa
what is common in the median cubital vein
- venipuncture
how do the superficial veins in the upper limb drain
- 2 superficial veins start from the dosral venous network these are the basillic vein and cephalic vein, these drain the superficial drainage, which is directedinto the deep veins so you can get it back more easily into the Venus drainage
- the basilica and cephalic plus the deep veins drain into the axillary vein
- the axillary vein becomes the subclavian veins
- the subclavian veins drains into the brachiocephalic vein and then into the superior vena cava to the heart
where does the abdominal aorta end and become the common iliac arteries
- ends at L4 dividing into the common iliac arteries
what does the common iliac divide into
- internal iliac artery
- external iliac artery
where does the common iliac divide
- At level of sacroiliac joints, common iliac arteries divided into 2 branches, S1
what is the internal iliac supply
supplies pelvic walls and plevic visceral, and gluteal region
- Superior and inferior gluteal arteries supply the gluteal muscles
- Obturator artery – comes forward and off the anterior division of the internal illac and goes through and goes to the hip
what does the external iliac supply
supplies the lower limbs
what does the internal iliac divide into
- Divides into posterior and aniterior
- Posterior = superior gluteal arteery – comes from inside the pelvis and through nothces
- Anterior – obtruatory and inferior gluteal artereis
where does the obturator artery go and what does it supply
- Passes through the obturator froamen
- Acetabular branch supplies the hip joint and head of the femur – important in children
- This is the antieror division
where does the femoral artery start
- Continuation of external iliac artery as it passes under the inguinal ligament, this changes from the external iliac to the femoral artery
- Passes down anteromedial thigh giving off several branches
what is the femoral triangle
- it is the place where there is an artery (femoral artery), vein and nerve in a consistent location that can be located easily so therefore it is popular in surgery
where is the femoral pulse
• Below inguinal ligament and mid-inguinal point
– Half-way between pubic symphysis and anterior superior iliac spine
what is the deep inguinal ring
- This is a hole in the traversalise fasica that lies 3cm superior to the mid point of inguinal ligament
- The vas deferens passes through this strucutre
- Direct hernias are medial to this point
what are indirect hernias
- Indirect hernias are loops of intestines that push throught the deep ring down the inguinal canal and out into the scrotum via the superifical ring
what is the branch of the femoral artery called
- profunda femoris - this means that it is the deep artery of the thigh
what does the profunda femoris supply
- This is the main arteiral supply to the thigh muscles (quardriceps, hamstrings and adductors)
- From profunda femoris arise the lateral and medial circumflex artereis
- The circumflex arteries supply the neck and head of the femur
what does the profunda femoris split into
lateral circumflex
medial circumflex
- they anatomise
where does the lateral circumflex go
– heads laterally and passes anteriorly around neck of femur and head
where does the medial circumflex go
– Initially goes medially then passes posteriorly around neck of femur and head
where does the popliteal artery start
- Enters the popliteal fossa (back of the knee)
* Changes its name to popliteal artery
where is the popliteal artery
- Close to knee the femoral artery passes through a gap in the adductor magnus muscle
- The adductor hiatus
what does the popliteal artery split into
- it has lots of collateral circulation
- splits into the anterior tibial artery and posterior tibial artery
describe where the popliteal pulse is
- Diffiuclt to find because it is deep in the politeal fossa
- Person prone with knee flexed to relax the popliteal fascia and hamstrings
- Pulsations are best felt in the inferior part of the fossa where the popliteal artery is closer to the tibia
- Tend to ignore if you can find the distal pulses then you know the popliteal pulse is there
where does the anterior tibia artery run and what does it supply
- Runs through the anterior compartment of the leg
- Supplies the dorsiflexors and extensors of the ankle and foot
what is larger the posterior tibial or the anterior tibial
posterior tibial - Larger of the two arteries from popliteal artery because it is suppling a bigger compartment
what does the posterior tibial divide into
- fibular artery/ peroneal arteyr
where does the posterior tibial artery run
• Passes down the posteromedial side of the leg.
- supplies the plantarflexors and lateral muscles of the legs
what is the branch called of the posterior tibial artery
• Fibular or peroneal artery is deeper branch from posterior tibial artery
describe the dorsalis pedis artery, what it supplies
- Continuation of the antieror tibial artery distal to the infieror extensor retinaculum
- Supplies the dorsum of the foot giving off branches to the arcuate artery from which the metatarsal arteries arise
what does the dorsalis pedis artery split into
- arcuate artery from which the metatarsal arteries rise
where do you feel the dorsalis pedis pulse
– Lateral to tendon of extensor hallucis longus
where do you feel the posterior tibial pulse
– Half-way between medial malleolus and calcaneal tendon
what does the posterior tibial artery divide at the ankle in to
– Lateral plantar
– Medial plantar
what does the lateral plantar form
• Lateral plantar forms lateral end of plantar arch from which the digital arteries arise.
what are the types of veins in the leg
deep
superficial
describe deep veins
• Deep veins run within the fascia and take the name of the artery they run with e.g. popliteal, femoral etc.
what are the two superficial veins in the lower limb
• Superficial veins run outside of fascia 2 main veins
– Small saphenous
– Great saphenous
there is smooth muscle in these veins
where does the small saphenous drain
- Small saphenous drains into the popliteal vein at the knee
where does the great saphenous drain
- Great saphenous is the longest vein in the body, it drains into the femoral vein just distal to the inguinal ligament
what allows the movement of blood from superficial to deep
- Superficial veins have numoerus perforating veins that connect with the deep veins
- Valves only allow blood to flow from suerpficial to deep
what controls venous return
- Movement from superficial to deep veins
- Respiratory pump
- Muscular pump
- Smooth muscle (venoconstriction)
- Valves
describe peripheral artery disease
• Occlusive disease of the arteries of the lower extremities
• Most common cause
– Atherosclerosis, arteritis, aneurysm and embolism
• Pathophysiology
– Arterial narrowing = decreased blood flow = pain
– Pain results from an imbalance between supply and demand
