sacral plexus nerves

Question 1

sacral plexus lies largely on what muscle?

Answer 1

piriformis muscle

Question 2

sacral nerves enter the pelvis via

Answer 2

anterior sacral foramina

Question 3

cutaneous supply of the posterior femoral cutaneous nerve

Answer 3

distal part of the buttocks, posterior thigh and popliteal fossa

Question 4

posterior femoral cutaneous nerve is formed from?

Answer 4

anterior AND posterior divisions

Question 5

the superior gluteal nerve leaves the pelvis via what?

Answer 5

the superior part of the greater sciatic notch

Question 6

superior gluteal nerve is anterior or posterior division?

Answer 6

posterior division of spinal nerves

Question 7

motor supply of superior gluteal nerve

Answer 7

gluteus medius and minimus, tensor fascia lata

Question 8

inferior gluteal nerve leaves the pelvis via the?

Answer 8

inferior part of the greater sciatic notch

Question 9

inferior gluteal nerve is anterior or posterior division?

Answer 9

posterior division of nerves

Question 10

motor supply of inferior gluteal nerve

Answer 10

gluteus maximus

Question 11

which nerve is the main sensory nerve to the external genitalia?

Answer 11

pudendal nerve

Question 12

is the pudendal nerve anterior or posterior division?

Answer 12

anterior division of spinal nerves

Question 13

what is the largest nerve in the body?

Answer 13

sciatic nerve

Question 14

where does the sciatic nerve leave the body?

Answer 14

through the greater sciatic notch, deep to piriformis muscle

Question 15

motor supply of sciatic nerve

Answer 15

adductor magnus, semitendinosus, semimembranosus, biceps femoris

Question 16

what are the 2 part of the sciatic nerve?

Answer 16

tibial nerve and common fibular nerve

Question 17

the tibial nerve forms what and supplies what?

Answer 17

forms the anterior division and supplies muscles and skin of posterior leg and plantar surface of foot

Question 18

the common fibular nerve forms what and supplies what?

Answer 18

forms the posterior division and wraps around the neck of the fibula and has 2 branches

Question 19

what are the 2 branches of the common fibular nerve?

Answer 19

deep fibular and superficial fibular and they supply the muscles and skin of anterior leg, lateral leg and dorsum of foot

Question 20

where do the 2 nerves of the sciatic nerve (tibial and common fibular) separate from the sciatic nerve?

Answer 20

just above or in the popliteal fossa

Question 21

what are 3 common causes of injury to the sciatic nerve?

Answer 21

1. fracture of pelvis
2. posterior dislocation of hip joint
3. penetrating wound

Question 22

injury to the sciatic nerve will have what motor symptoms?

Answer 22

• hamstring muscles atrophy but weak flexion is still possible
• all muscles distal to the knee may be involved
• the foot falls into plantar flexed position

Question 23

injury to the sciatic nerve will have what sensory symptoms?

Answer 23

loss of sensation below the knee except for an area along the medial side of the leg and foot

Question 24

causes of sciatica

Answer 24

1. compression, inflammation and/or subluxation of L4-S3(prolapse of intervertebral disc/ herniated disc)
2. compression neuropathy of sciatic nerve in gluteal area
3. intrapelvic tumor