Nerve Palsies in the Limbs

Question 1

What are the clinical features involved in axillary nerve lesions?

Answer 1

• Deltoid atrophy
• Loss of sensation over regimental badge area

Question 2

What are the clinical features of radial nerve lesions?

Answer 2

Lesion in Axilla - Loss of elbow extension, wrist extension and sensory changes in forearm and hand

Lesion in arm - Loss of wrist extension and sensory loss

Lesion in forearm - Loss of finger extension

Question 3

What are the clinical features of median nerve palsies (carpal tunnel syndrome)?

Answer 3

Carpal tunnel syndrome

• Nocturnal pain and parastheisa
• Pain worst in morning
• Wasting of Thenar muscles

Question 4

What are the clinical features of ulnar nerve lesions?

Answer 4

Cubital tunnel syndrome

• Ulnar claw hand
• Muscle wasting in 1st webspace
• Hypothenar wasting

Question 5

What are the clinical features of brachial plexus palsies?

Answer 5

Upper brachial plexus - Erb’s palsy (waiters tip position)

Lower brachial plexus - Klumpke’s palsy (claw hand)

Question 6

What is the innervation of the lower limb?

Answer 6

Sacral Plexus:

• Sciatic L4, 5, S1, 2, 3 (Common Peroneal nerve & Tibial nerve)

Lumbar Plexus:

• Femoral nerve L2, 3, 4

Question 7

What are the clinical features of a lesion to the common peroneal nerve?

Answer 7

• Foot drop (unable to dorsiflex the foot)

Question 8

Through which foramen of the vertebral column do spinal nerves exit?

Answer 8

Intervertebral foramen

Question 9

What are the myotome patterns of the upper limb? I.e. what muscle do they innervate?

Answer 9

C5 - Flexors of elbow

C6 - Extensors of wrist

C7 - Extensors of elbow

C8 - Extensors of fingers

T1 - Intrinsic hand muscles

Question 10

What are the myotome patterns of the lower limb? I.e. what muscle do they innervate?

Answer 10

L2 - Hip flexors

L3 - Knee extensors

L4 - Extensors of the ankle

L5 - Extension of the big toe

S1 - Flexors of the ankle

Question 11

Which nerve roots are affected in Erb’s palsy?

Answer 11

C5

C6

Question 12

Which nerve roots are affected in Klumpke’s palsy?

Answer 12

C8

T1

Question 13

Which muscles are affected in Klumpke’s palsy?

Answer 13

Small muscle of hand

Question 14

What is Hilton’s law?

Answer 14

A sensory nerve supplying a joint also supplies the muscles moving that joint and also innervates the skin overlying the insertions of these muscles

Question 15

What can cause axillary nerve palsy?

Answer 15

1 - Shoulder dislocation

2 - Fracture of surgical neck of humerus

Question 16

Which muscle becomes atrophied as a result of an axillary nerve palsy?

Answer 16

Deltoid

Question 17

What are the contents of the carpal tunnel?

Answer 17

Flexor digitorum superficialis x 4 tendons

Flexor digitorum profundus x 4 tendons

Flexor pollicus longus x 1 tendon

Median nerve

Question 18

What are some of the causes of carpal tunnel syndrome?

Answer 18

Gout

Rheumatoid

Distal radius fracture

Ganglion

Question 19

What tests can be performed to check for carpal tunnel syndrome?

Answer 19

Tinnels (tapping)

Phalens (reverse prayer)

Question 20

What test can be used to check for Ulnar nerve palsies?

Answer 20

Froment’s test (grabbing paper)

Question 21

What is the main nerve of the sacral plexus?

Answer 21

Sciatic nerve

Question 22

What are the main nerves of the lumbar plexus?

Answer 22

Femoral nerve

Obturator nerve

Question 23

Which two nerves does the sciatic nerve split into?

Answer 23

1 - Tibial nerve

2 - Common fibular nerve