Nerve Palsies of the Limbs

Question 1

What is Hilton’s law?

Give a clinical example of why this is important

Answer 1

The nerves crossing a joint supply the muscles acting on it and the joint itself

May supply 2 joints e.g. hip and knee supplied by femoral, sciatic and obturator nerves ->

HIP DISEASE MAY GIVE RISE TO KNEE PAIN

Question 2

Name 3 nerves that supply the hip joint

Answer 2

Obturator nerve (predominantly)

Femoral nerve

Lateral femoral cutaneous nerve

Question 3

What is a myotome?

Answer 3

Group of muscles supplied by one segment of spinal cord

Question 4

Give a pneumonic to remember the development of the brachial plexus from roots

Answer 4

Rob = Roots
Trenson = Trunks
Drinks = Divisions
Cold = Cords
Beer = Branches

Question 5

What are the roots of the radial nerve?

Answer 5

C5-T1

Question 6

The radial nerve enters the forearm by passing between which two mucles?

Answer 6

Brachioradialis and brachialis

posterior interosseous branch of radial nerve passes between 2 planes of supinator

Question 7

What 2 locations are the radial nerve at risk of damage?

Answer 7

Spiral grrove of humerus

Lateral intermuscular septum

Question 8

What deficit occurs in radial nerve damage?

Answer 8

Motor = wrist drop (extensors)

Sensory = 1st web space dorsally
-Dorsum of hand, web between thumb and index and middle finger

Question 9

What are the roots of the median nerve?

Answer 9

C7, 8 and T1

Question 10

How does the median nerve enter the forearm?

Answer 10

By passing between the two heads of pronator teres

Question 11

What is the clinical significance of struther’s ligament?

Answer 11

Its clinical significance arises from the fact that the median nerve and brachial artery may pass through the “arch” formed by the process and ligament over the humeral body. Within this space the nerve may be compressed leading to supracondylar process syndrome.

Question 12

What are the roots of the ulnar nerve?

Answer 12

C7-T1

Question 13

What is the deficit of ulnar nerve damage?

Answer 13

Motor = claw hand, hypothenar and 1st dorsal interosseous wasting

Sensory = little finger

Question 14

Where does the lumbar plexus lie?

Answer 14

On the surface of quadratus lumborum and within body of posts muscle

Question 15

What major nerves about the hip do not exit the pelvis by the sciatic foramen?

Answer 15

Genitofemoral
Ilioinguinal
Femoral
Lateral femoral cutaneous
Obturator nerves

Question 16

What are the roots of the femoral nerve?

Answer 16

L2-4

Question 17

The femoral nerve terminates in a long fine sensory branch called the saphenous nerve.

Describe the route of this nerve

Answer 17

Accompanies femoral artery in subsartorial canal of thigh and long saphenous vein in lower leg and in front of medial malleolus at ankle to supply breat toe

Question 18

The lateral femoral cutaneous nerve lies on the surface of which muscle?

Answer 18

Iliacus muscle

usually exits pelvis under lateral end of inguinal ligament but variable

Question 19

What does the lateral femoral cutaneous nerve supply?

What occurs when it is compressed?

Answer 19

Purely sensory to lateral aspect of thigh

Compression causes meralgia parasthetica

Question 20

What are the roots of the sciatic nerve?

Answer 20

L4-S3

Question 21

What does the sciatic nerve supply?

Answer 21

Hamstring muscles in thigh (posterior) and part of adductor magnus and all lower leg and foot muscles via terminal branches

Question 22

What can cause damage to sciatic nerve?

Answer 22

At risk from posterior dislocation of hip, intra-muscular injections and during surgery

Question 23

What is the most commonly injured nerve in lower limb?

What deficit does it cause?

Answer 23

Common fibular nerve

Foot drop and slapping gait

Question 24

Where is the common fibular nerve at risk?

Answer 24

Passes around lateral aspect of neck of fibula