Upper/Lower Limb Neurological Examination Flashcards
What are the different types of generalised seizure?
- Absence: brief staring episode
- Myoclonic: extremely brief muscle contractions that look like jerky movements
- Tonic: tense contraction of muscles
- Clonic: rhythmic muscle contractions
- Tonic-clonic: initial muscle contraction (tonic phase) followed by rhythmic muscle contractions (clonic phase)
- Atonic: loss of muscle tone
List 3 causes of a bilateral upper motor neurone lesion
Bilateral upper motor neurone lesions can be remembered using the 3M’s:
MS
Motor neurone disease → normal sensation
Myelopathy – cord compression (e.g. due to cervical myelopathy, SOL, disc prolapse, paraspinal infection), trauma, transverse myelitis, syringomyelia, congenital → sensory-level/segmental sensory loss
Others – brainstem stroke, hereditary spastic paraplegia, cerebral palsy, HTLV-1, syphilis
What would be your differential diagnosis for a sensorimotor polyneuropathy?
Use ABCDE to list causes of a sensorimotor polyneuropathy:
Alcohol
B12/thiamine deficiency
Charcot-Marie-Tooth, Carcinomas (paraneoplastic)
Diabetes, Drugs (e.g. TB drugs, metronidazole/nitrofurantoin, vincristine/cisplatin, amiodarone)
Every vasculitis (e.g. SLE, RA, polyarteritis nodosa) and some infections (e.g. herpes zoster, HIV, leprosy, syphilis)
Which conditions may result in a unilateral upper motor neurone lesion?
Work down (brain to cord):
Intracranial – stroke, SOL → hemisensory loss
Brainstem – stroke, SOL → may be crossed signs
Spinal cord – MS, infarct/haemorrhage, SOL, disc prolapse, trauma, syringomyelia, congenital → sensory-level/segmental sensory loss
What are the causes and clinical features of a Brown-Sequard syndrome?
A Brown-Sequard syndrome is caused by damage to one half of the spinal cord. It is characterised by loss of power and proprioception on the ipsilateral side, and loss of pain and temperature on the contralateral side. This is because the spinothalamic tract decussates in the spine, whereas the other tracts decussate in the brainstem.
What is the differential diagnosis for a bilateral proximal weakness?
Bilateral proximal muscle weakness is usually caused by a myopathy.
The differential diagnosis can be remembered using DENIM:
Dystrophies – Becker’s/Duchenne, limb girdle, facioscapulohumeral (shoulder, face and truncal weakness)
Endocrinological – Cushing’s syndrome, hyper/hypothyroidism, diabetic amyotrophy (lower limbs)
Neuromuscular – myasthenia gravis (fatigable), Lambert–Eaton myasthenic syndrome
Inflammatory – dermato-/polymyositis, inclusion body myositis (proximal in legs but distal in arms), viral myositis
Metabolic/congenital/mitochondrial myopathies
Name some conditions associated with carpal tunnel syndrome. Name some other causes of a median nerve palsy.
Carpal tunnel syndrome may be associated with:
Pregnancy
Obesity
Rheumatoid arthritis
Local extrinsic pressure, e.g. ganglion, lipoma, fracture, haematoma
Endocrinological
Diabetes
Hypothyroidism
Acromegaly
Some other causes of median nerve palsy include: penetrating forearm injuries, pronator teres syndrome, mononeuritis multiplex
What are the causes of a radial nerve palsy?
Causes may include:
Trauma/compression at axilla (e.g. crutches, sleeping over chair, i.e. ‘Saturday night palsy’, stabbing injury)
Humeral shaft trauma (fracture)
Elbow trauma (fracture, dislocation, ganglion)
What are the clinical features that would suggest motor neurone disease during the upper limb clinical examination?
In motor neurone disease, the most common findings would be:
An exclusive motor deficit (no sensory abnormalities)
Classically a combination of LMN and UMN signs, for example in the upper limb exam you may see muscle wasting and fasciculations, but with increased tone and brisk reflexes
There may also be other clues, for example the patient may be in a wheelchair due to spastic paraparesis, and/or a speech abnormality (bulbar/pseudobulbar palsy)
Which hand muscles does the median nerve supply?
All thumb muscles except adductor pollicis – ‘LOAF’
Lateral two lumbricals
Opponens pollicis
Abductor pollicis brevis
Flexor Pollicis brevis
Which hand muscles does the ulnar nerve supply?
All intrinsic hand muscles except most of thumb:
Adductor pollicis
Lumbricals
‘Pad Dab’
Palmar interossei (adduct)
Dorsal Interossei (abduct)
Which hand muscles does the radial nerve supply?
Extensors
What can cause damage to the ulnar nerve and how would this present?
Causes
– Cubital tunnel syndrome
– Fractures
– Guyon’s canal
Presentation
– Numbness in the ring and little finger
– Reduced finger abduction and adduction
– Reduced adduction of the thumb
– Weak grip strength
– Muscle wasting
– Clawing of digits 4 and 5
What are the different management options for carpal tunnel syndrome?
Conservative
– The use of a night-time splint to hold the wrist in dorsiflexion
Medical
– Simple analgesia to relieve the pain
– Corticosteroid injections
Surgical
– Decompression surgery
What are some types of dysarthria?
Bulbar palsy = flaccid
Pseudobulbar palsy = spastic
Cerebellar = slurred, staccato (broken up into syllables, i.e. jerky), scanning (variability in pitch/volume)
Myasthenic = weak, quiet, fatigable
Please describe the difference between Broca’s and Wernicke’s aphasia. Damage to which areas of the cerebral cortex cause each of these aphasias?
Broca’s (expressive) aphasia:
This is a type of non-fluent aphasia
It is characterised by the inability to produce language, both spoken and written
Comprehension of speech is often intact
Caused by damage to the frontal lobe of the dominant hemisphere (often left)
Wernicke’s (receptive) aphasia:
This is a type of fluent aphasia
These patients have difficulty producing coherent sentences and understanding speech
The production of speech is intact
Caused by damage to the posterior superior temporal lobe
Which tests may be used to assess muscle fatiguability in patients with myasthenia gravis?
- Counting aloud 1 to 30 (speech will be clear initially but will become increasingly dysarthric)
- Single breath counting aloud 1 to 20 (may elicit dysarthria and dyspnoea)
- Sustained eye upgaze: ask patient to focus on your finger superiorly for 60+ seconds (results in ptosis)
- Test abduction of the arms and repeat after asking the patient to abduct/adduct repeatedly for 10-20 repetitions (power will be reduced after repetitions)
- Ask patient to stand from sitting and sit down again with their arm crossed. Ask them to repeat this up to 20 times (should exacerbate leg weakness)
How would a patient present if they had complete damage to cranial nerve X (Vagus nerve)?
The soft palate droops to one side
Loss of gag reflex
Dysphasia
Hoarse and nasal voice
Tachycardia
Gastroparesis/nausea and vomiting
Difficulties with GI transit and digestion
How would you differentiate between and bulbar and pseudobulbar palsy?
Bulbar palsy is due to LNM pathology, whereas pseudobulbar palsy is due to UMN pathology. There are therefore different signs:
Tongue wasting and fasciculations in bulbar palsy (spastic in pseudobulbar palsy)
Absent gag reflex in bulbar palsy (increased/normal in pseudobulbar palsy)
Speech in bulbar palsy = flaccid = indistinct with nasal twang
Speech in pseudobulbar palsy = spastic = monotonous, high- pitched, ‘Donald Duck’ dysarthria
Please list some causes of Parkinsonism
Parkinson’s disease
Vascular parkinsonism
Parkinson-plus syndromes
Other causes (e.g. drugs, Wilson’s disease)
What are the Parkinson-plus syndromes?
Progressive supranuclear palsy: vertical limitation, axial rigidity
Multi-system atrophy: cerebellar signs, autonomic problems
Corticobulbar degeneration
Dementia with Lewy bodies
What is the Parkinson’s disease tetrad?
Tremor
Rigidity
Bradykinesia
Postural instability
List some clinical features of Parkinson’s disease
Stooped posture
Hypomimia
Reduced arm swing
Shuffling gait
Slowness
Multiple falls
Anosmia
Postural hypotension
Depression
Restless leg syndrome
Which common class of drugs may cause drug-induced parkinsonism?
Antipsychotics. Their mechanism of action is dopamine depleting hence why the side effects can mimic Parkinson’s disease
