7.1 LL Nerves & Vessels

Question 1

What are the arteries of the LL?

Answer 1

-external iliac artery
-femoral artery + profunda femoris: deep artery of the thigh
supplies to most lower limbs

pass the adductor canals, hole-adductor hiatus ->

• popliteal artery, back of knee
• Tibial arteries (anterior and posterior)

Question 2

Name the superficial veins of the LL

Answer 2

• dorsal venous arch
• great saphenous (medial see in shower)
• small saphenous (posterior)
  (all in superficial fascia)

Question 3

Name the deep veins of the LL

methods that ensure unidirectional flow

Answer 3

• venae comitantes
• venous sinuses in soleus
• muscular venous pump

Question 4

Describe lymphatics of the lower limb

Answer 4

drainage follows superficial veins of the lower limb:

• inguinal nodes
• drain to thoracic duct – left side

Question 5

What do nerves of the lower limb arise from?

Answer 5

• Anterior rami give rise to plexuses
• Major nerves arise from Lumbosacral plexus

mixed rami-motor giving rise to lumbosacral plexus sensory which innervates the entire lower limb

Question 6

Femoral nerve

supply?

Answer 6

L2-L4
Supplies
-extensor/anterior compartment of thigh, innervates all the anterior muscles of the thigh
-quadriceps
-skin: anterior thigh, medial leg and foot

passes under inguinal ligament

Question 7

Obturator nerve

supply?

Answer 7

L2-4  
Supplies 
-adductor (medial) compartment of the thigh
-adductor muscles
-skin: medial aspect thigh
- enters obturator canal in pelvis 

referred pain from ovary hip pain referred to knee

Question 8

Gluteal nerve

Answer 8

L4, L5, S1
supplies all 3 gluteal muscles-lateral compartment of thigh

-exits the pelvis through the greater sciatic foramen

Question 9

Sciatic nerve

Answer 9

L4, L5 S1 S2 S3
innervates all hamstring muscles and all posterior muscles of the thigh
+ sensory sensation around leg and foot

divides at apex of popliteal fossa into 2 branches:
tibial nerve
common peroneal nerve

Clinical significance: ‘sciatica’,
gluteal injections
chronic hamstring strains

can be damaged through hip dislocation
well protected in posterior compartment by hamstrings

Question 10

Damage to sciatic nerve

Answer 10

Intervertebral disc prolapse at L5/S1 Irritation of the S1 nerve root
affect S1 nerve-innervates lower leg and foot, referred pain on back…

Question 11

Tibial nerve

Answer 11

L5 S1-3
supplies all posterior compartment leg muscles
- arises at the back of knee (politeal fossa)
- enters tarsal tunnel and divides into plantar nerves

Clinical significance
Compression of :
- tibial nerve in the tarsal tunnel (‘tarsal tunnel syndrome’)
- plantar nerves below medial arch (‘jogger’s foot’)

Question 12

Common Peroneal / Fibular nerve

Answer 12

L4-5 S1-2

superficial fibular nerve - lateral compartment- ankle eversion

deep fibular nerve - anterior compartment-extension=dorsiflexion
-passes around the head of fibula

Compression of:
- common peroneal nerve at lateral knee – ‘foot drop’
- anterior compartment syndrome (deep fibular nerve)
(L4,5 S1,2)

Question 13

What are the arteries of the LL?

Answer 13

External iliac artery
Femoral artery + profunda femoris
Popliteal artery- back of knee
Tibial arteries (anterior & posterior)

Question 14

Describe the passage way of the arteries

When do they change names?

Answer 14

external iliac artery-> crosses inguinal ligament & into femoral triangle->femoral artery
profunda femoris artery/deep femoral artery branch of femoral artery
Exit femoral triangle-> femoral artery continues down the anterior surface of the thigh, via a tunnel known as the adductor canal. During its descent the artery supplies the anterior thigh muscles.
The adductor canal ends at an opening in the adductor magnus, called the adductor hiatus. The femoral artery moves through this opening, and enters the posterior compartment of the thigh, proximal to the knee. The femoral artery now known as the popliteal artery.