Download ST 2 neuropathies - My Surgery Website

Tom Gamble and Jo Swallow
20/11/13
Describe the presentation and causes of the following:
 Median nerve (carpal tunnel syndrome)
 Ulnar nerve
 Radial nerve
 Sciatic nerve
 Lateral cutaneous nerve
 Common peroneal nerve
 Tibial nerve
 Bell’s Palsy
 Ramsay Hunt
 The radial nerve may be damaged anywhere in its
course. It is most commonly affected in the upper arm
where it winds round the humerus
 Finger and wrist drop are common, their severity
depending upon the site of the lesion.
 sensory loss on the dorsum of hand and forearm
appropriate to the cutaneous distribution - see radial
nerve anatomy
 terminal of the sciatic nerve, providing motor supply







to the muscles of the anterior and lateral leg.
most commonly damaged nerve in the lower limb and
traverses the lateral aspect of the head of the fibula.
foot drop
weakness of dorsiflexion and eversion of the foot
weakness of extensor hallucis longus
inversion and plantar flexion are normal
anaesthesia over the lower lateral part of the leg and
dorsum of the foot; often with little or no sensory loss
all reflexes are intact - the ankle jerk is lost in a sciatic
nerve lesion
 entrapment of the lateral cutaneous nerve of the thigh
is named meralgia paraesthetica
 Damage to the tibial nerve is uncommon. Most
usually, there is paralysis of gastrocnemius which is
easily tested by asking the patient to stand on tiptoe
 The Ramsay Hunt Syndrome is characterised by
sensorineural deafness, vertigo and facial paralysis
following Herpes Zoster infection. The patient is
usually elderly. ?Treatment
 otalgia - pain in the ear and the mastoid region - often
with few signs on examination
 a vesicular eruption involving the external ear
 facial paralysis, deafness and vertigo
 ipsilateral loss of taste in the anterior two-thirds of
tongue
 Mononeuritis multiplex is a condition which is
characterised by multiple individual nerve palsies, for
example an ulnar nerve palsy in one arm, a radial nerve
palsy in the other arm, and an asymmetrical foot drop
due to a lateral popliteal nerve lesion.
 Metabolic: Diabetes; renal failure; hypothyroidism;







hypoglycaemia; mitochondrial disorders
Inflammatory: Guilain Barre; sarcoid
Vasculitis: PAN; Rheumatoid arthritis; Wegener’s
Malignancy
Infection: Lyme disease; HIV; syphilis; leprosy
Vitamin deficiency (Vit B1,6,12 – alcoholism)
Drugs: alcohol; isoniazid; nitrofurantoin; phenytoin
Inherited porphyria; Charcot Marie Tooth
 Glucose; FBC; U&E; B12, TFTs +/- LFTs, autoimmune
profile,syphilis serology
 ?Motor – eg guillain – barre
 ?sensory
 Painful – eg diabetic, alcoholic, B12 defic
Other, demyelenation, axonal
 Guillain-Barre syndrome is an acute, inflammatory,




postinfectious polyneuropathy.
A prodromal malaise with vomiting, headache, fever
and limb pains is rapidly surmounted by a progressive
and ascending paralysis. This can lead to respiratory
dysfunction, and as such, the acute presentation can
be a neurological emergency.
The incidence is 2 per 100 000 per year.
Usually within 3 wks of a viral illness
Muscle weakness evolves over 3-21 days. It may be
generalised, proximal in distribution, or commence
distally and ascend
 Treatment for Guillain-Barre syndrome is supportive.
Early tracheostomy is indicated if there is progressive
bulbar and respiratory weakness
 Specific treatment for Guillain-Barre syndrome
consists of high-dose intravenous immunoglobulin
(IvIg) or plasma exchange
 Myasthenia gravis is an acquired autoimmune disorder
characterised by weakness, typically of the periocular,
facial, bulbar, and girdle muscles.
 serum IgG antibodies to acetylcholine receptors in the
postsynaptic membrane of the neuromuscular
junction. Classically, the muscles are easily fatigued.
 It affects 5 people in every 100 000
 external ocular muscles - affected in over 90% of cases,
and are the muscles first affected in 65% of cases;
diplopia or ptosis, often asymmetrical, are typical
 oral anticholinesterase medication, e.g.
pyridostigmine or neostigmine
 thymectomy - required if there is a thymoma because
of the risk of local infiltration
 immunosuppression with corticosteroids +/- cytotoxic
agents is also highly effective in inducing remission of
disease