Nerves and vessels of the lower limb

Question 1

How many sacral nerves are there?

Answer 1

5

Question 2

How many coccygeal nerves are there?

Answer 2

1

Question 3

Which spinal nerves supply each of the following:
Neck 
Upper Limb
Trunk
Lower Limb
Perineum

Answer 3

Neck: C1-C4
Upper Limb: C5-T1
Trunk: T2-L1
Lower Limb: L2-S3
Perineum: S2-C1

Question 4

Which muscles does the superior gluteal nerve innervate?

Answer 4

Gluteus medius
Gluteus minimus
Tensor fasciae latae

Question 5

The femoral nerve innervates all the muscles in the anterior compartment of the thigh. Which extra spinal root contributes to the innervation of iliopsoas?

Answer 5

L1

Question 6

Which nerve roots are responsible for:
Inversion
Eversion
Toe Extension
Toe Flexion

Answer 6

Inversion: L4
Eversion: L5S1
Toe Extension: L5S1
Toe Flexion: S12

Question 7

What nerve supplies sensory innervation to most of the posterior of the thigh?

Answer 7

Posterior cutaneous nerve of the thigh

Question 8

Which two spinal nerve roots are responsible for sensory innervation of most of the posterior side of the lower limb?

Answer 8

S1 and S2

Question 9

What are autonomous sensory zones?

Answer 9

Regions where you can be confident of the spinal root affected if there is any abnormal sensation in those regions

Question 10

Which part of the lower limb does the obturator nerve supply sensory innervation to?

Answer 10

Inner part of the thigh

Question 11

Which part of the leg does the saphenous nerve provide sensory innervation to?

Answer 11

Medial part of the leg

Question 12

Which nerve provides sensory innervation to most of the dorsum of the foot?

Answer 12

Superficial peroneal nerve

Question 13

Where can the common peroneal nerve be damaged easily?

Answer 13

At the neck of the fibula

Question 14

What are the consequences of damage to the common peroneal nerve?

Answer 14

Foot drop
Loss of sensation to the dorsum of the foot at least
No change in reflexes or autonomic function

Question 15

Describe the position of the posterior tibial artery relative to the medial malleolus.

Answer 15

It is posterior to the medial malleolus

Question 16

Where can the dorsalis pedis pulse be felt?

Answer 16

Just lateral to the extensor hallucis longus tendon

Question 17

Where can the posterior tibial artery pulse be felt?

Answer 17

Just posterior to the medial malleolus

Question 18

What is cut-down and when it is performed?

Answer 18

It is an emergency procedure to gain access to the veins of a patient in shock

Question 19

Where is the incision made in cut-down?

Answer 19

2 cm lateral and proximal to the medial malleolus

Question 20

What is intermittent claudication?

Answer 20

Muscle pain induced by exercise and relieved by rest, that is caused by inadequate blood supply to the affected muscles (associated with arterial disease)

Question 21

What is compartment syndrome?

Answer 21

Ischaemia caused by trauma-induced increased in pressure in a confined limb compartment

Question 22

What is the normal pressure in muscle compartments?

Answer 22

25 mm Hg

Question 23

What pressure is required to collapse vessels?

Answer 23

50-60 mm Hg

Question 24

What are the causes of acute and chronic compartment syndrome?

Answer 24

Acute – trauma-associated

Chronic – exercise-induced

Question 25

What is the treatment of acute compartment syndrome?

Answer 25

Emergency fasciotomy

Question 26

How do varicose veins form?

Answer 26

Valve dysfunction in the superficial, deep and perforating veins Saphenofemoral junction valve is the most important NOTE: can cause lipodermatosclerosis and ulcers

Question 27

Divisions of lumbosacral plexus

Answer 27

Either anterior or posterior Note: Posterior divisions tend to supply anterior compartments due to how leg pronates during embryology

Question 28

Supply of femoral nerve

Answer 28

Anterior thigh compartment

Question 29

Supply of obturator nerve

Answer 29

Medial adductor compartment of thigh

Question 30

Supply of sciatic nerve

Answer 30

Posterior thigh | All of leg and foot

Question 31

Branches of sciatic nerve

Answer 31

Tibial and common peroneal

Question 32

Significance of piriform muscle with regards to vessels

Answer 32

Anything above is superior gluteal and anything below is inferior gluteal

Question 33

Where does sciatic nerve branch

Answer 33

Just superior to knee condyles on posterior side

Question 34

Route of common peroneal nerve

Answer 34

Wraps laterally around fibula to anterior side just below knee

Question 35

Route of tibial nerve

Answer 35

Descends down posterior side of tibia

Question 36

Division of tibial nerve

Answer 36

At foot becomes medial and lateral plantar nerve

Question 37

5 lower limb nerves

Answer 37

``` Femoral Obturator Sciatic Superior gluteal Inferior gluteal ```

Question 38

Spinal nerves of femoral nerve

Answer 38

L234 posterior fibres

Question 39

Spinal nerves of obturator nerve

Answer 39

L234 anterior fibres

Question 40

Spinal nerves of sciatic nerve

Answer 40

L3 4 5 and S123 | Anterior and posterior fibres

Question 41

Spinal nerves of sup gluteal

Answer 41

L4 and 5 | S1

Question 42

Spinal nerves of inf gluteal

Answer 42

L5 S12

Question 43

Supply of superior gluteal nerve

Answer 43

Gluteus medius and minimus | Tensor fascia lata

Question 44

Supply of inferior gluteal nerve

Answer 44

Gluteus maximus

Question 45

Supply of sciatic nerve

Answer 45

Posterior thigh | Leg and foot

Question 46

Principles of segmental supplies

Answer 46

Muscles supplied by 2 adjacent segments Any same action on joint supplied by same nerve supply Opposing muscles 1-2 segments above or below The more distal in the limb the more caudal the cell body in spine

Question 47

Signs of prolapsed disc L5/S1

Answer 47

Motor loss of eversion Sensory loss of outer foot Loss of ankle jerk

Question 48

Overall blood supply to leg

Answer 48

External iliac Femoral Popliteal Trifurcation to anterior and posterior tibial and peroneal

Question 49

Route of femoral artery

Answer 49

Run down anterior compartment of thigh and to the posterior of knee through hiatus of adductor Magnus

Question 50

Point at which femoral becomes popliteal

Answer 50

After passing posteriorly through hiatus of adductor Magnus

Question 51

What does anterior tibial artery become

Answer 51

Dorsalis pedis artery just softer crossing artery

Question 52

What forms greatsaphenous vein

Answer 52

Dorsal venous arches of foot just anterior and superior to medial malleolus

Question 53

Where does saphenous vein join femoral vein

Answer 53

After passing through saphenous opening

Question 54

Main superficial veins of leg

Answer 54

Small saphenous and great saphenous

Question 55

Importance of perforating veins in leg

Answer 55

Contain valve allowing blood flow from superficial veins

Question 56

Important thing regarding venous grafts

Answer 56

Valves only allow flow in one direction so when done must be orietated properly