Lower Extremity

Question 1

Lumbosacral plexus

Answer 1

innervation of the entire lower extremities
[ ] L1-4 = anterior innervation
[ ] L5-S4 = posterior innervation

Question 2

Femoral nerve

Answer 2

L2-4 –> anterior thigh and medial foot

Question 3

Lateral femoral cutaneous nerve

Answer 3

L1-3 –> lateral skin of thigh

Question 4

Obturator nerve

Answer 4

L2-4 –> Adduction and inner thigh

Question 5

Femoral nerve block

Answer 5

L2-4 –> inguinal ligament, sartorius, adductor longus

- gives some weakness to quads

Question 6

Nerve stim femoral

Answer 6

Firing of quads

- cephalad direction just lateral to artery just below the inguinal ligament

Question 7

U/S femoral

Answer 7

lateral to the vessels

- in-plane block

Question 8

Fasci Iliaca

Answer 8

inserted into the fascia iliaca on the lateral 2/3 and pass through 2 pops

Question 9

LFCN block

Answer 9

it travels laterally through the psoas –> emerges inferior and medial to ASIS

Question 10

Psoas block

Answer 10

useful to cover femoral, obturator and LFCN (spares the sciatic nerve)

• DEEP block in muscle beds, possibility for epidural/intrathecal spread
• lateral decubitus position with operative side up

Question 11

Saphenous block/Adductor Canal

Answer 11

blocks most medial branch of femoral nerve

• innervates medial thigh toward knee and inner lower leg
• useful for pain at/below knee

Question 12

Trans-sartorial AC

Answer 12

at junction of sartorius, vastus medialis, adductor magnus

Question 13

Proximal Saphenous

Answer 13

distal to tibial tuberosity and direct medially

Question 14

Sciatic Block

Answer 14

L4-S3 –> blockade of posterior leg

• good analgesia and lacks sympathectomy
• great coverage of lateral foot

Question 15

Popliteal block

Answer 15

great coverage of foot and ankle –> spares the hamstrings

Question 16

Nerve stim popliteal

Answer 16

posterior approach –> 1 cm caudad needle entry from opening of biceps femoris and semimembranous
-> plantar flexion

Question 17

U/S popliteal

Answer 17

popliteal artery is most anterior structure

• nerve is posteriolateral to vessels
• peanut nerve bundle

Question 18

Ankle block

Answer 18

- great coverage of foot, avoid high volume and epi
5 injections:
1. saphenous
2. deep peroneal
3. superficial peroneal
4. Posterior Tibial
5. Sural