Peripheral Neuropathy

Question 1

What is peripheral neuropathy?

Answer 1

Dysfunction of peripheral nerves due to local damage, compression or peripheral disease

Question 2

What is radiculopathy?

Answer 2

Compression of spinal nerve roots

Question 3

What are the symptoms of radiculopathy?

Answer 3

Sensory disturbance and weakness in nerve root dysfunction

Question 4

What is plexopathy?

Answer 4

Nerve dysfunction at the level of a nerve plexus

Question 5

What are the symptoms of plexopathy?

Answer 5

Sudden onset of neuopathic pain with associated numbness, tingling and weakness

Question 6

What is the presentation of motor nerve peripheral neuropathy (symptoms, power, sensation, reflexes)?

Answer 6

Weakness, gait disturbance, wasting
Reduced power
Normal sensation
Absent reflexes

Question 7

What is the presentation of large sensory nerve peripheral neuropathy (symptoms, power, sensation, reflexes)?

Answer 7

Numbness, paraesthesia, ataxia
Normal power
Vibration and proprioception sensation decreased
Absent reflexes

Question 8

What is the presentation of small sensory nerve peripheral neuropathy (symptoms, power, sensation, reflexes)?

Answer 8

Pain, dysesthesia (abnormal sensation)
Normal power
Pin prick and temperature sensation decreased
Reflexes present

Question 9

What is the presentation of autonomic nerve peripheral neuropathy (symptoms, power, sensation, reflexes)?

Answer 9

Dizziness, impotente, bladder disturbance, nausea/vomiting
Normal power
Normal sensation
Reflexes present

Question 10

What is mononeuropathy?

Answer 10

Peripheral neuropathy in which a single nerve is affected

Question 11

What is mononeuropathy caused by?

Answer 11

Peripheral nerve compression and entrapment

Focal demyelination occurs at compression site and some axonal degeneration happens

Question 12

What is axonal degeneration?

Answer 12

Damage to axons
Nerve fibre dies back from the periphery
Conduction velocity initially normal as continuity is maintained in surviving fibres
Length dependent neuropathy

Question 13

What does length dependent neuropathy mean?

Answer 13

Longest, most vulnerable axons (to the toes) damaged first

Question 14

What investigation is done for mononeuropathies?

Answer 14

Nerve conduction studies

Question 15

What is the main example of a mononeuropathy?

Answer 15

Median nerve (carpal tunnel syndrome)

Question 16

What are the symptoms of carpal tunnel syndrome?

Answer 16

Aching pain in hand at night
Loss of sensation over thumb, index, middle and lateral half of third finger
Thenar wasting and weakness in grip strength

Question 17

What conditions are associated with carpal tunnel syndrome?

Answer 17

Diabetes
Rheumatoid
Overuse
Pregnancy

Question 18

What is the management for carpal tunnel syndrome?

Answer 18

Splinting
Steroid injections
Decompression surgery

Question 19

What are the symptoms of ulnar nerve neuropathy?

Answer 19

Sensory loss over medial 1.5 fingers
Development of ulnar claw
Hypothenar muscle wasting
Weakness in wrist flexion and flexion of 4th/5th DIP

Question 20

What is the management of ulnar nerve neuropathy?

Answer 20

Surgical decompression

Question 21

What are the symptoms of radial nerve neuropathy?

Answer 21

Wrist drop
Weakness of brachioradialis and finger extension
Loss of sensation in dorsal first web space

Question 22

What is the management of radial nerve neuropathy?

Answer 22

Supportive - usually recovers within 1-3 months

Question 23

What are the symptoms of lateral cutaneous nerve of the thigh nerve neuropathy?

Answer 23

Burning thigh pain

Question 24

What are the symptoms of common fibular nerve neuropathy?

Answer 24

Foot drop

Loss of sensation laterally below the knee and over the dorm of the foot

Question 25

What are the symptoms of tibial nerve neuropathy?

Answer 25

Sensory loss over sole of foot Weakness in plantar flexion (unable to stand on tiptoes) Weakness in inversion of the foot and flexion of the big toes

Question 26

What is mononeuritis multiplex?

Answer 26

When 2 mononeuropathies in distinct locations develop at the same time

Question 27

What are causes of mono neuritis multiplex?

Answer 27

``` Diabetes Rheumatoid Carcinomatosis Vasculitis: Wegener's, PAN Infection: HIV, leprosy ```

Question 28

What are the general features of presentation of polyneuropathy?

Answer 28

Usually symmetrical and widespread Sensory symptoms - in glove and stocking distribution with subsequent proximal spread Motor symptoms - progressive weakness with associated respiratory difficulties Can be autonomic, cranial nerve symptoms

Question 29

What are the types of damage in polyneuropathy?

Answer 29

Axonal damage | Demyelination

Question 30

What are the causes of axonal damage causing polyneuropathies?

Answer 30

Metabolic: diabetes, renal failure, hypothyroidism Nutritional: B12, copper, zinc Vasculitic: Wegener's, PAN, rheumatoid Infections: HIV, syphilis, Lyme Drug/toxins: alcohol, cisplatin, vincristine, isoniazid Malignancy: paraneoplastic

Question 31

What is the mechanism of damage in demyelination?

Answer 31

Schwann cell damage leads to myelin sheath disruption | This causes marked slowing of conduction

Question 32

What are causes of demyelination causing polyneuropathies?

Answer 32

Guillian-Barre syndrome CIDP - chronic inflammatory demyelinating polyneuropathy Charcot-Marie Tooth Disease

Question 33

What is Guillian-Barre syndrome?

Answer 33

Acute, autoimmune inflammatory demyelinating peripheral neuropathy

Question 34

What is the presentation of Guillian-Barre syndrome?

Answer 34

Usually few weeks after infection (upper resp, GI) Ascending muscle weakness starting in the lower limbs and spreading, usually over a four week period leading to paralysis Associated pain, sensory loss, autonomic dysfunction, cranial nerve symptoms Loss of reflexes

Question 35

What is the clinical course of of Guillian-Barre syndrome?

Answer 35

Typically worsening of paralysis for up to four weeks and then recovery phase starts - full recovery is seen in the majority of patients

Question 36

What investigations are done in Guillian-Barre syndrome?

Answer 36

Neve conduction studies - slowed conduction | Lumbar puncture - increased protein with normal white cells

Question 37

What is the management of Guillian-Barre syndrome?

Answer 37

IV immunoglobins Plasmapheresis +/- ventilatory support

Question 38

What is CIDP (chronic inflammatory demyelinating polyneuropathy)?

Answer 38

Variant of Guillian-Barre syndrome associated with slower onset of symptoms and a much slower recovery (months – years)

Question 39

What is Charcot-Marie Tooth Disease?

Answer 39

Heredity sensory motor neuropathy

Question 40

What is the presentation of Charcot-Marie Tooth Disease?

Answer 40

Begins around puberty Progressive distal muscle wasting in the legs giving rise to champagne shaped legs Associated lower limb weakness Foot drop and high stepping gait +/- sensory disturbance and loss of reflexes

Question 41

What is the management of Charcot-Marie Tooth Disease?

Answer 41

Physiotherapy

Question 42

What investigations are done for peripheral neuropathies?

Answer 42

``` Bloods Urinalysis Chest x ray Lumbar puncture Nerve conduction studies ```