nerves and vessels of lower limb

Question 1

what spinal levels supply which region *

Answer 1

c1-4 neck

c5-t1 upper limb

t2-l1 trunk

l2-s3 lower limb

s2-c1 perineum

Question 2

what are teh 2 types of innervation *

Answer 2

segmental - dermatomes

peripheral - nerves to muscles and cutaneous nerves

Question 3

where do peripheral nerves emerge from *

Answer 3

nerve plexuses

Question 4

what is a nerve plexus *

Answer 4

it is formed when peripheral spinal nerve roots merge and split to produce a network of nerves from which new multi-segmental peripheral nerves emerge

multi-segmental means that fibres come from >1 spinal root

Question 5

what are the 3 main nerves that supply the lower limb that come off the lumbosacral plexus *

Answer 5

femoral

obturator

sciatic

Question 6

summarise the organisation of the lumbosacral plexus *

Answer 6

come of levels L2-S3

derived from the anterior rami of the spinal nerves

terminal branches have fibres off different roots

the lumbar plexus is derived from L1-L4, branches are:

• iliohypogastric and ilioinguinal nerves
• genitofemoral nerve
• lateral cutaneous nerve of thigh
• femoral nerve
• obturator nerve
• lumbosacral trunk

sacral plexus is derived from lumbosacral trunk and s1-4 anterior rami

• sciatic nerve
• nerve to piriformis
• posterior cutaneous nerve of the thigh
• pelvic splanchnic nerves - pns
• pudendal nerves
• nerve to obturator internus
• superior gluteal nerve
• inferior gluteal nerve

Question 7

describe the anatomy of the gluteal region and the course of the sciatic nerve through it *

Answer 7

piriformis is one of the lateral rotator cuff muscles - important landmark

superior to piriformis have the superior gluteal nerve and vessels

inferior to the piriformis have the inferior gluteal nerve and vessels, and large nerves - the sciatic and posterior cutaneous nerve of thigh

sciatic then passes posterior in thigh and divides into tibial and common peroneal nerve

Question 8

describe the femoral nerve *

Answer 8

L2-4

supplies - anterior compartment of the thigh and iliacus (hip flexor in pelvis - L1-4) [psoas and iliacus, pectineus, sartorius, rectus femoris, vastus medialis, vastus intermedius, vastus lateralis]

from lumbosacral plexus, passes under the inguinal canal, enters the femoral triangle and branches

it is a posterior division of the plexus but supplies anterior muscles because of the pronation that occurs in development

sensory to front of thigh and anteromedial knee

terminal branch is saphenous nerve - sensory to medial leg and foot

Question 9

describe teh obturator nerve *

Answer 9

L2-4

supplies the medial - adductor compartment of thigh [obturator externus, adductor brevis and longus, part of adductor magnus, gracilis]

sensory to pelvis and upper medial aspect of thigh

comes off the lumbrosacral plexus and emerges on medial border of psoas muscle, runs inferiorly and anteriorly on pelvis and passes through the obturator foramen by piercing the fibrous membrane and muscle covering

is anterior division of the plexus

Question 10

describe the sciatic nerve *

Answer 10

L4-S3

2 nerves that are stuck together - 1 anterior and 1 posterior division

passes through the greater sciatic foramen, behind the hip, then passes in posterior part of thigh

sciatic nerve proper supplies hamstring muscles in posterior part of thigh [biceps femoris, semimembranosus and semitendinosus, part of adductor magnus]

also has some sensory branches to back of thigh, lateral side of leg and foot, dorsal surface of foot

nerve divides just above the knee

branches are tibial and common peroneal branches

supply posterior thigh, anterior and posterior leg and foot ie all muscles in leg and foot

Question 11

describe the tibial nerve *

Answer 11

l4-s3

branch of the sciatic nerve

stays posteriorly, runs on teh surface of the tibialis posterior and supplies posterior leg [gastrocnemius and soleus, plantaris, popliteus, tibialis posterior]

runs posterior to the medial malleolus, passes under the plantar aporneurosis where it divides into medial (L4 5)and lateral (S1 2) plantar nerves - supplies all muscles of the foot [flexor hallucis longus, flexor digitorum longus and brevis, abductor hallucis, fkexor hallucis brevis, interossei and lumbricles]

sensory to the back of teh leg and the sole of the foot and lateral side of foot

Question 12

describe the common peroneal nerve *

Answer 12

L4-S2

branch of the sciatic nerve in posterior compartment of thigh/popliteal fossa

follows the medial margin of the biceps femoris tendon over the lateral head of the gastrocneumius to the fibular (here gives off sural nerve)

passes laterally round neck of fibular

give off deep (L5-S2) and superficial (L4-S1) peroneal nerves

superficial descends in lateral compartment, deep to fibularis longus and brevis

superficial supplies the lateral compartment of the leg ie the peroneus longus and brevis

a branch of superficial emerges just superior to the ankle joint where it divides into medial and lateral branches that supply cutaneous dorsum of foot - except for the web space between digits 1 and 2 (supplied by deep peroneal) and lateral side of little toe (supplied by tibial)

deep passes anteromedially from lateral part of leg through the intermuscular septum into the anterior compartment of the leg the passes deep to the extensor digitorum longus, reaches the nterosseous membrane where it meets and descends with the tibial artery

the deep supplies the anterior compartment of the leg [tibialis anterior, extensor hallucis longus, peroneus tertius, extensor digitorum longus], the goes to dorsal foot - innervates extensor digitorum brevis, contributes to innervation of the 1st two dorsal interossei muscles

deep supplies skin between teh 1st adn 2nd digits

Question 13

where is the common peroneal nerve suseptible to damage *

Answer 13

round teh neck of the fibula

Question 14

describe the saphenous nerve *

Answer 14

it is a branch of the femoral nerve

accompanies femoral artery through adductor canal but doesnt pass through adductor hiatus; instead it penetrates through connective tissue in canal - appears between sartorius and gracialis muscles on medial side of knee

here penetrates deep facia and continues down medial side of leg to foot

it a cutanous nerve of medial knee, leg and foot

Question 15

what does the femoral nerve supply *

Answer 15

anterior compartment of thigh - motor

medial leg and foot - sensory via the saphenous nerve

Question 16

describe the sural nerve *

Answer 16

formed from branches of the common peroneal nerve and tibial nerve

tibial part originate between heads of gastrocnemius, descends superficially to gastrocnemius, penetrates the deep fascia

here joined by sural communicating nerve from common peroneus

passes down leg and round the lateral malleolus and into the foot

it is a cutanous nerve of the lateral leg and foot and little toe

Question 17

describe the superior gluteal nerve *

Answer 17

L4-S1

pass into gluteal region via the greater sciatic foramen superior to piriformis

supplies glut med and min and tensor fascia lata

Question 18

describe inferior gluteal nerve *

Answer 18

L5-S2

pass into the gluteal region via greater sciatic foramen inferior to the piriformis

supplies glut max

Question 19

summarise the segmental supply to the limbs *

Answer 19

groups of motor nerve cell bodies in teh spinal cord

plexi for each limb

anterior division/rami - flexor muscles which are posterior

posterior division/rami - extensor muscles which are anterior

muscles are supplied by 2 adjacent segments

if muscles have the same action on a joint - have same nerve supply

opposing muscles have supply from 1-2 segments above/below

the more distal the muscle, the more caudal in spine the segment

Question 20

spinal segments that are involved in movementof the limbs *

Answer 20

hip - flex L2-3, extend L4 5

knee extend l3 4 flex l5 s1

ankle dorsiflex (extension) - l4 5, plantarflex s1-s2

Question 21

what are dermatomes *

Answer 21

fields of the cutaneous surface whose sensation is supplied by a single spinal nerve

Question 22

what is an axial line in reference to dermatomes *

Answer 22

boundary between lower and higher spinal roots

where the dermatomes are not linked at the spinal level eg s2 and l2 lie next to each other in posterior thigh

Question 23

who is the peripheral nerve supply different to the dermatomes *

Answer 23

peripheral supply refers to peripheral nerves not the spinal roots

not all fibres from 1 spinal root go via 1 peripheral nerve

also, peripheral nerves contain fibres from >1 spinal roots

for example posterior cutaneous nerve comes from S1 2

Question 24

what are autonomous sensory zones *

Answer 24

dermatomes overlap - so difficult to know what has been affected in spinal root damage

autonomous sensory zones are zones taht if you have abnormal sensation in them, it is indicative of spinal root damage for a particular dermatome

eg L3 region on thigh, L4 knee, S1 back of calf

obturator nerve enters medially and supplies muscle and skin of medial thigh - autonomous sensory zone

deep fibular nerve supplies cleft between 1st and 2nd digit - autonomous sensory zone

Question 25

describe the cutanous innervation of foot \*

Answer 25

saphenous nerve supply medial side of ankle and foot deep and superficial peroneal nerves - become dorsal digital nerves dorsal lateral cutaneous nerve - from sural nerve supplies lateral of foot have common and proper plantar digital nerves and lateral and medial plantar nerve and medial calcaneal nerve on sole of foot

Question 26

what do you assess in assessment of nerve function \*

Answer 26

motor, sensory, reflex, autonomic and trophic

Question 27

effect of prolapsed intervertebral disk at L5/S1 \*

Answer 27

cause pressure on S1 nerve root - cause segmental loss motor - loss of eversion and weakness elsewhere sensory - loss of sensation on outer border of foot reflex - loss of ankle jerk S1 autonomic - minimal - abnormalities in sweating in the S1 cutaneous nerve distribution trophic - in long standing lesions there might be trophic changes in the lateral aspect of the foot

Question 28

effect of lesion of common peroneal nerve at fibular neck \*

Answer 28

peripheral nerve loss motor - foot drop because of paralysis of anterior and lateral compartments of legs (cant raise toes so scuff front of shoes and have high stepping/swinging gait - can get springs to lift toes artificially iff long term) sensory - dorsum of foot at least reflex - none autonomic - minimal - abnormalities of sweating in cutaneous distribution of the common preoneal nerve trophic - in chronic cases may be damage to sole of foot due to pressure effects of foot drop

Question 29

summarise the arterial anatomy \*

Answer 29

aorta branches into common iliac arteries that branch into external and internal iliac arteries at pelvic brim - external is the main blood supply to lower limb (internal stays in pelvis exept for 1 branch is the obturator artery which passes through the obturator foramen into the thigh) superior and inferior gluteal arteries are branches of the internal iliac external pass under inguinal ligament at mid-inguinal point (halfway between syphysis pubis and ASIS) to become femoral which passes anteriorly in thigh femoral has 4 branches below inguinal ligament - superficial circumflex iliac artery, superficial epigastric artery, superficial external pudendal artery, deep external pudendal artery femoral gives off deep branch in the femoral triangle - the profunda femoris artery, this arises 4cm distal to the inguinal ligament - its branches are the perforating arteries and medial and lateral femoral circumflex arteries - they supply the distal head of the femer femoral passes from anterior to posterior through the adductor hiatus to become the popliteal artery popliteal artery gives off genicular (knee) branches popliteal artery ''trifurcates'' - not true trifurcation branches into anterior tibial artery and tibioperoneal artery tibioperoneal then branches into peroneal and posterior tibial artery anterior tibial pierces interosseous membrane then is deep in anterior compartment between bones running on the interosseous mem, becomes dorsalis pedis artery when it passes over the ankle, passing anteromediolaterally to turn laterally as the arcuate artery giving off the digital branches perforating arteries communicate between the plantar arch adn arcuate artery posterior tibial passes into posterior compartment of leg alongside the tibialis posterior around medial malleolus and branches into lateral and medial plantar arteries which form a plantar arterial arch, supplying sole of foot

Question 30

what are the pulse points in the lower limb \*

Answer 30

femoral artery popliteal posterior tuibial dorsalis pedis

Question 31

why are pulses important \*

Answer 31

aging population need to assess vascular health lower limb is further away from heart so there are more issues suseptible to PVD - need to know legs are being perfused

Question 32

why is the femoral triangle important \*

Answer 32

for access to the heart femoral pulse important for cannulation for cardiac arteriography access artery for resuscitation - vein

Question 33

describe the femoral artery and vein's relation to adductor magnus \*

Answer 33

they pass from anterior to posterior through teh adductor hiatus (of the adductor hiatus muscle) the passing through the hiatus is a point where occlusion can occur superficial short saphenous vein drains into the popliteal vein at the popliteal fossa

Question 34

describe the arrangement of vessels in the popliteal fossa \*

Answer 34

the artery is deeper than the vein

Question 35

what bone do you press the femoral artery against for pulse \*

Answer 35

pubic ramus at mid-inguinal point it lies on the psoas tendon so can be palpated easily

Question 36

what bone do you press dorsalis pedis artery against for pulse \*

Answer 36

tarsal bones and maybe metatarsal

Question 37

where do you feel the posterior tibial artery \*

Answer 37

behind the medial malleolus

Question 38

describe the path of the superficial veins \*

Answer 38

lie in the subcutaneous tissue, have valves to prevent the backflow of blood great and short saphenous emerge from the dorsal venous arch great emerges from medial portion of arch and passes 2cm anterior and posterior to medial malleolus - travels up medial of leg, skirts behind medial femoral condyle of knee, pass up medial thigh going more anteriorly - through the saphenous opening (the cribiform fascia) 3cm below and lateral to the pubic tubercle to join the femoral vein. a number of venous tributaries join the vein here short saphenous drains the lateral part of arch, goes behind the lateral malleolus, up posterior of leg with the sural vein, pierces fascia over the popliteal fossa and drains into the popliteal vein short and long vein communicate at many levels the popliteal vein lays in fossa between popliteal artery and tibial nerve the femoral vein passes behind the femoral artery and lies medial to it at inguinal ligament just before the long saphenous joins femoral, profunda femoris vein joins the femoral when femoral goes under the inguinal ligament it becomes the external iliac vein

Question 39

describe the depp veins of the lower limb \*

Answer 39

they run alongside the arteries as venae comitantes

Question 40

describe venae comitantes \*

Answer 40

they are accompanying veins multiple veins form a network of smaller veins with arteries which they accompany there are connections between the venae comitantes this allows heat exchange - cooled blood in veins from peripheries is warmed by blood from the arteries artery pulses promote venous return

Question 41

what is cut down of the long saphenous vein \*

Answer 41

when patient in shock and all vessels have collapsed but you need to give them fluid cut long saphenous vein 2cm lateral and proximal to the medial malleolus and get fluid in this way - small canular is inserted into vein not used as much today - flouid given byu interosseous administration - a needle inserted into the bone marrow of anterior tibia in well equipt fascilities US can be used tp find a patent vein

Question 42

describe arterial embolism \*

Answer 42

caused by sudden occlusion of an atherosclerotic vessle or by a thrombus formed by afib if a vessel is suddenly occluded with no time for a collateral circulation to develop = acute ischaemia intermittent claudication is where there is gradula occlusion of arteries, usually atherosclerotic - the muscles distal to occlusion become deprived of blood on exercise muscle pain, commonly in calf during activity

Question 43

describe compartment syndrome \*

Answer 43

the neuromuscular compartments of the limbs are enclosed in fibrous sheaths which confine them compartment syndrome is where ischemia is caused by trauma induced increased in pressure in a confined limb compartment - commonly anterior, posterior and lateral compartments of the leg normal pressure is 25mmHg - if rise to 50-60mmHg = collapse of small vessels, but BP is 120/80mmHg - so you can still feel pulse even though tissues are not being perfused acute compartment syndrome is trauma associated eg fractures or muscle damage/inflammation chronic - exercise induced - muscles get pumped up with increased pressure if built muscle mass quickly and the fascia hasnt had any time to adjust - exercise induced discomfort

Question 44

treatment of acute compartment syndrome \*

Answer 44

emergancy fasciotomy to prevent the death of muscle

Question 45

descrive varicose veins \*

Answer 45

perforating veins connect superficial and deep veins, they have a valve so blood only flows from superficial to deep - spheno-femoral junction is most important if valve is comprimised - blood pushed into superficial = swelling of superficial veins - leading to varicose veins valve may be comprimised if FH, lifestyle or multiple pregnancy can get ulcers/pain ulcers are important to consider in people with dm, older people and people who are less mobile can get lipodermatosclerosis - skin thickening because of the increased pressure in the superficial circulation - possible chronic inflammatory cause treatment involves tying off sapheno-femoral junction

Question 46

describe DVT \*

Answer 46

clot in deep veins mainly in lower limb risk factors - inactivity, long haul flights, surgery in abdo, pelvis or limbs, the pill often silent but can present with pain and swelling in calf or proximal thigh DVT can be dislodged - travel in veins and cause PE = sudden death a distal dvt occurs in calf, distal occurs in thigh/pelvis - prox is dangerous because high risk of PE dvts treated with anti-coag to avoid this can cause increased back pressure in the deep veins = venous insufficiency and leg ulcers - this is post-phlebitic syndrome superficial veins may also clot or be infected causing superficial thrombophlebitis - painful, the treatment is rest, ice, analgesic - less dangerous than dvt

Question 47

describe muscle pump of deep veins \*

Answer 47

valves mean blood only flows up leg deep veins are sandwiched between layers of calf muscles during movement - contraction of muscle squeeze veins and push blood up - they contract distal valve and open prox immobility means less efficient venous return from foot/leg - sluggish return = dvt elastic surgical socks compress superficial veins so more blood is pushed into deep system = more vigorous deep flow - redeuced chance of DVT

Question 48

describe venous grafts \*

Answer 48

coronary artery bypass graft this is arterial bypass surgery around an occlusion have to put the valves the right way round so that blood flows in right dirn because of the anastomoses in the leg, there is rarely a problem in removing a superficial vein

Question 49

what is included in the peripheral NS

Answer 49

cranial and spinal nerves

Question 50

what is a spinal nerve \*

Answer 50

formed from the union between an anterior (motor) and a dorsal (sensory) root the roots merge at the intervertabral foramen to form a spinal nerve

Question 51

where do autonomic fibres run

Answer 51

between t1-l2 and s2-4`

Question 52

describe path of spinal nerves \*

Answer 52

as soon as pass through intervertebral foramen splits into anterior and posterior ramus the anterior rami merge to form the major plexi of the limbs the posterior rami are less significant and are mainly cutaneous nerves

Question 53

dermatomes of lower limb \*

Answer 53

l3 front of thigh l4 front of leg l5 dorsum of great toe s1 lateral aspect of foot s2-s4 perineum and perianal region

Question 54

describe the sequence for the knee jerk reflex \*

Answer 54

tap stretch the patella tendon stimulation of afferent (1a) fibres in quadriceps passes to spinal cord through posterior root synapse with a motor neuron in anterior horn of the spinal cord efferent signal to quadriceps quadriceps extend the knee joint

Question 55

reflexes in the lower limb\*

Answer 55

stretch reflexes/deep tendon reflexes and are monosynaptic knee jerk - L3 ankle jerk - S1

Question 56

what is the sympathetic outflow to the lower limb

Answer 56

t11-l2

Question 57

when can the femoral nerve be damaged \*

Answer 57

iatrogenic - traction injuries via hip replacements and laproscopic repair of inguinal hernias or in erroneus attempted cannulations of the femoral a or n

Question 58

how can the lateral cutaneous nerve of the thigh be damaged \*

Answer 58

passes 2cm medial to the ASIS at level of inguinal ligament can be comprimised causing meralgia parasthesia - burning pain, numbness, and tingling sensation in the outer thigh.

Question 59

describe damage to the obturator nerve \*

Answer 59

rarely damaged pain in the distribution of teh obturator nerve could be indicative of malignant disease in pelvis

Question 60

describe injury to the superior gluteal nerve \*

Answer 60

results in Tredelenburg gait - pelvis lurches during gait commonest injury is during hip replacement nerve lies 5cm proximal to tip of greater trochanteur and approaches the hip joint - should not extend \>5cm from tip of greater trochanteur

Question 61

describe injury to the sciatic nerve \*

Answer 61

after hip replacement trauma eg hip dislocations or acetbular fractures pelvic disease common peroneal division more vulnerable than tibial

Question 62

how do you prevent damaging the sciatic nerve\*

Answer 62

give an intramuscular injection in upper lateral quadrant of buttock - nerve most likely situated in lower inner qudrant

Question 63

describe injury to the common peroneal nerve \*

Answer 63

at level of hip and round fibular neck from trauma, knee replacement, and external pressure - from plasters or during surgical procedures

Question 64

describe damage to the tibial nerve \*

Answer 64

very deep so rarely damaged in isolation

Question 65

describe damage to the saphenous nerve \*

Answer 65

common at medial malleolus after varicose vein surgery or at knee after ACL surgery

Question 66

describe anaesthetic nerve blocks

Answer 66

aid or substitute GA in surgery eg femoral, sciatic, ankle, lateral cut nerve blocks

Question 67

what is the location of the femoral canal \*

Answer 67

medial to femoral vein at inguinla ligament - within the canal is a lymph node

Question 68

palpate the femoral artery \*

Answer 68

in midinguinal point

Question 69

palpate the popliteal artery \*

Answer 69

in inferior of popliteal fossa against posterior surface of tibia

Question 70

palpate posterior tibial artery \*

Answer 70

behind medial malleolus

Question 71

palpate dorsalis pedis artery \*

Answer 71

dorsum of foot lateral to the extensor hallucis longus tendon

Question 72

what structures are at risk during venepuncture of femoral vein \*

Answer 72

femoral n femoral a femoral canal

Question 73

palpate the popliteal lymph nodes \*

Answer 73

only when enlarged around popliteal fossa along small saphenous vein

Question 74

palpate superficial inguinal lymph nodes \*

Answer 74

near the termination of long saphenous vein (deep inguinal nodes are along the proximal part of the femoral vein) only palpable when enlarged

Question 75

what are the levels of the dermatomes in the lower limb \*

Answer 75

l1 - inguinal region l2- thigh-upper lateral l3 - thigh- lower lateral l4 - leg and great toe medial l5 - leg anterolateral and foot and toes 2-4 dorsal s1 - sole lateral margin and heel s3-s4 buttock medial, intergluteal cleft and peineum

Question 76

how do you test the integrity of dermatomes \*

Answer 76

touch in them with crude and light touch

Question 77

describe the principle of deep tendon reflexes \*

Answer 77

when tendon is tapped and so stretched, there is involuntary contraction of that muscle

Question 78

test the patella tendon reflex - knee jerk \*

Answer 78

ask subject to sit comfortably with legs dangling on edge of couch examiner strike patella tendon with knee hammer should see brisk extension of knee joint palpate the contraction of the quadriceps compare to opposite sife

Question 79

test the calcaneal tendon reflex \*

Answer 79

ask pt to sit comfortably with legs dangling on edge of couch - examiner should strike calcaneal tendon with a knee hammer while holding foot slightly dorsiflexed with other hand plantar flexion of ankle joint will occur might be absent of S1 sopinal nerve root is affected or tibial nerve damage

Question 80

how would you test integrity of femoral nerve \*

Answer 80

extension of the knee - test the quadriceps sensation on anterior of thigh and medial side of leg and foot

Question 81

how would you test for integrity of the obturator nerve \*

Answer 81

check adduction - medial compartment of thigh sensation on medial compartment of thigh

Question 82

what is sciatica \*

Answer 82

pain in the area of distribution of the sciatic nerve l4 to s3 - over the buttock and in the posterolateral aspect of the leg

Question 83

what is the significance of anastomoses \*

Answer 83

the femoral circumflex arteries, inferior and superior gluteal and obturator arteries, with branches from the internal pudnendal branches anastomose in gluteal and upper thigh region- these anastomoses can provide collateral circulation if one of the vessels becomes occluded genicular branches from the femoral, popliteal and lateral circumflex arteries in thigh and the circumflex fibular artery and recurrent branches from the anterior tibial artery in leg form an anastomotic network around the knee joint

Question 84

describe the contents of the femoral triangle with regard to arterial sampling and catheter placement \*

Answer 84

contents are: femoral nerve, artery, vein, lymph nodes (which are in femoral canal) from laterally to medially radiological approaches involve catheterisation of fem a or v to get access to contralateral limb, ipsilateral limb, the vessels of the thorax and abdomen and the cerebral vessels use the fem a to place catheters in vessels around the arch of the aorta and into coronary arteries to perform coronary angiography and angioplasty access to fem v allows catheters to be manovered in renal and gonadal veins, the R atrium, R side of heart - pulmonary artery and distal vessels of the pulmonary tree access to superior vena cava and great veins is also possible

Question 85

describe the lymphatic drainage of the lower limb \*

Answer 85

most drain into superficial and deep inguinal lymph nodes located in the fascia just below the inguinal ligament superficial inguinal nodes - approx 10 are in the superficial fascia and follow course of inguinal ligament; medially they extend inferiorly along terminal part of the great saphenous vein superficial recieve lymph from gluteal region, lower abdo wall, perineum, and superficial regions of lower limb superficial drain via vessels that accompany femoral vessels into external iliac nodes, associated with external iliac artery deep inguinal - up to 3 in number, medial to femoral vein, recieve lymph from deep lymphatics associated with femoral vessels and glans penis/clitoris deep interconnect with superficial and drain into external iliac nodes via vessels medial to femoral vein popliteal nodes - deep nodes close to popliteal vessels - they recieve lymph from superficial vessels which accompany superficial saphenous vein, and deep areas of leg and foot popliteal drain into superficial and deep inguinal

Question 86

describe how lymph drainage is related to tumour/infection spread \*

Answer 86

lymph drains areas in the leg if these areas are affected or have cancer - these cells will be drained to the nodes this causes the node to be active - the rapid cell turnover and production of local inflammatory mediators cause node to enlarge and become tender because the flow through the nodes is slow, cells metastisise away from primary tumours and enter lymphatic vessels - lodge and grow as secondary tumours in lymph nodes