Obturator Nerve Flashcards Preview

ESA 2- Musculoskeletal System > Obturator Nerve > Flashcards

Flashcards in Obturator Nerve Deck (23):
1

What are the nerve roots of the obturator nerve?

L2-L4

2

What are the motor functions of the obturator nerve?

Innervates the medial (adductor compartment) of the thigh

3

What are the sensory functions of the obturator nerve?

Cutaneous branch innervates the skin of the medial thigh

4

What is the obturator nerve formed by?

The anterior divisions of the 2nd, 3rd and 4th lumbar nerve

5

What is the anatomical course of the obturator nerve?

It descends through the fibres of the psoas major muscle and emerges from its medial border, running posteriorly to the common iliac arteries and laterally along the pelvic wall to the obturator foramen 
It enters the thigh through the obturator canal

6

What happens to the obturator nerve once it’s entered the thigh?

It splits into anterior and posterior divisions

7

What course does the anterior division of the obturator nerve take?

It descends between the adductor longus and adductor brevis muscles, towards the femoral artery

8

What branches does the anterior division give off?

To the adductor longus, adductor brevis, and gracilis 
In rare cases, it also gives off a branch to the pectineus muscle

9

What does the anterior division of the obturator nerve become?

The cutaneous branch of the obturator nerve

10

What does the obturator nerve become the cutaneous nerve of the obturator nerve?

When it pierces the fascia lata

11

What course does the posterior division of the obturator nerve take?

It descends through the obturator externus muscle before passing anteriorly to the adductor magnus and giving off branches to supply it

12

What muscles does the obturator nerve innervate?

Adductor longus
Adductor brevis 
Adductor magnus
Gracilis 
Obturator externus

13

What does the adductor longus do?

Adducts thigh

14

What does the adductor brevis do?

Adducts thigh

15

What does the adductor magnus do?

Adductor part adducts and flexes thigh
Hamstring part extends thigh

16

What does the gracilis do

Adducts thigh

17

What does the obturator externus do?

Laterally rotates thigh

18

What does the cutaneous branch of the obturator nerve supply?

The skin of the middle part of the medial thigh

19

How can the obturator nerve be damaged?

During surgery involving the pelvis or abdomen

20

What are the symptoms of obturator nerve damage?

Numbness and paraesthesia on the medial aspect of the thigh 
Weakness in adduction of the thigh
Posture and gait problems

21

When is obturator nerve block used?

In the management of pain after lower limb surgery, or for chronic hip pain

22

How is obturator nerve block induced?

The anaesthetic is injected inferior to the pubic tubercle and lateral to the tendon of the adductor longus muscle

23

How is the obturator nerve block procedure carried out?

Under ultrasound guidance