Neuropathy W4 Flashcards
what is neuropathy
disease of peripheral nerves
mononeuropathy?
individual nerve affected
polyneuropathy?
many nerves involved
typically longest nerves damaged first
(glove and stocking distribution)
mononeuritis multiplex?
multiple mononeuropathies
neuropathy classification by modalities affected?
sensory
motor
autonomic/visceral
(can affect one/some/all modalities!)
sensory neuropathy types and features?
large fibre - crude touch, vibration, proprioception
small fibre - pain, temperature
autonomic/visceral neuropathy features?
affects digestion, heart rate and BP regulation, sweat, bladder/bowel and sexual functions
neuropathy classification by pattern of damage?
demyelinating - damage to myelin sheath
axonal - damage to axon
could be both!
how to work out if neuropathy is demyelinating or axonal?
nerve conduction studies
clinical features of neuropathy?
sensory disturbance
pain
weakness
secondary features
sensory disturbance in neuropathy features?
pain (pinprick), temperature, touch, proprioception and/or vibration
pain in neuropathy features?
sometimes present, typically neuropathic (burning, stabbing, tingling)
weakness in neuropathy features?
accompanied by wasting, loss of reflexes
secondary features in neuropathy?
wounds/ulcers
fractures (inc. chronic, poorly healed fractures eg Charcot joints)
charcot joints?
occurs in patients who aren’t aware they’ve had a fracture due to loss of pain sensation. put weight on it and healed in abnormal fashion.
mononeuropathy features
sensory loss and paraesthesia
and/or motor weakness in select muscle groups
paraesthesia?
burning/prickling sensation usually felt in hands, arms, legs, feet
can occur in other parts of body
common peroneal (fibular) mononeuropathy - area affected?
lateral aspects of leg, dorsal side of foot
lateral cutaneous mononeuropathy - area affected? what’s this associated with?
anterior thigh
overweight
mononeuropathy - median nerve vulnerable site?
carpal tunnel
mononeuropathy - ulnar nerve vulnerable site?
Guyon’s canal (wrist)
cubital tunnel (elbow)
mononeuropathy - radial nerve vulnerable site?
axilla, spiral groove of humerus
mononeuropathy - lateral cutaneous nerve vulnerable site?
inguinal ligament
mononeuropathy - common peroneal nerve vulnerable site?
fibular neck
commonest mononeuropathy?
carpal tunnel syndrome
carpal tunnel syndrome features?
pain and paraesthesia
loss of function in important hand movements
features of carpal tunnel syndrome pain and paraesthesia?
typically at night
patients ‘wake and shake’
associations of carpal tunnel syndrome?
pregnancy
hypothyroidism
rheumatoid arthritis
diabetes
treatment of carpal tunnel syndrome?
splints
surgical release
common causes of polyneuropathy?
diabetes
alcohol
medications
B12 deficiency
immune
hereditary
examples of immune causes of polyneuropathy?
acute - Guillain-Barre syndrome
chronic - CIDP
example of hereditary cause of polyneuropathy?
Charcot-Marie-Tooth disease
what is Guillain-Barre syndrome?
acute inflammatory disorder - autoimmune polyneuropathy
Neurological emergency!!!!!!!!!!!!! (patients require hospitilization)
Guillain-Barre syndrome trigger?
infectious trigger in prior weeks
classically C. jejuni
Guillain-Barre syndrome pathophysiology?
antibodies generated against infections then attack similar antigens in peripheral nerves
attack on myelin and sometimes axons
Guillain-Barre syndrome clinical features?
ascending weakness pattern (length-dependant)
treatment of Guillain-Barre syndrome?
supportive measures (weakness may affect diaphragm, may require ventilation in ICU)
IVIg or plasma exchange
clinical features seen in neuropathy on examination?
muscle weakness and wasting (length dependant distal fashion)
tendon reflexes lost (length dependant distal fashion)
sensory loss
coordination affected (if there is sensory ataxia - loss of proprioception)
diabetic neuropathy?
chronic slowly progressive
microvascular damage to nerves, particularly small fibre nerves (pain/temperature)
risk to foot health (patients don’t perceive painful stimuli)
what does diabetic neuropathy often arise with
retinal and renal disease
management of diabetic neuropathy
prevention
podiatry
sometimes amputations
inherited neuropathy features?
gradually progressive issues with walking/running, foot sensation
exam of inherited neuropathy may show what?
wasting, high arched feet, hammer toes, ulcers, reduced reflexes, weakness (bilateral foot drop)
