Neurology Short
The Neurology short is not about nailing the exact diagnosis. Most of the time, it may not be known (to the examiners as well), and it is more about the examination skills, and having a logical process/system to try and localise the lesion/pathology.
A consultant once taught the me the following structure when thinking about and presenting the Neurology short case. Essentially there are three main questions/concepts to think of:
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What is the syndrome?
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If you have identified the syndrome, where is the lesion/defect on the neuroaxis that is causing it?
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If you have identified where on the neuroaxis, what is the aetiology of this underlying lesion?
I'll expand on this.
By syndrome, I mean is this a 1) unilateral upper arm weakness, 2) bilateral distal lower limb weakness, 3) bulbar palsy, 4) spastic paraparesis, 5) cranial nerve palsy, and so on...
By neuroaxis, I am thinking more anatomical - i.e. working backwards, from muscles > neuromuscular junction > peripheral nerves > anterior and dorsal horns > spinal cord (with ascending and descending tracts) > brain stem > hemispheres. Some area lie outside of this framework - for example, the cerebellum and 'extrapyramidal' lesions such as in Parkinson's.
And then lastly, in terms of the underlying lesion, this is referring to the ultimate cause such as tumour, vascular, demyelination, trauma and so on.
As a simple example:
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Syndrome: bilateral symmetrical distal lower limb weakness
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Neuroaxis: peripheral neuropathy
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Lesion: diabetic neuropathy
Another example:
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Syndrome: spastic paraparesis
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Neuroaxis: spinal cord
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Lesion: previous trauma
Another example:
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Syndrome: proximal weakness without sensory involvement or upper motor neuron signs
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Neuroaxis: myopathy (discussing peripheral neuropathy, NMJ etc as differential)
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Lesion: e.g inflammatory (polymyositis) vs. acquired (statin, steroid, nutritional, alcohol).
Another example:
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Syndrome: Bulbar weakness
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Neuroaxis: affecting anywhere from brainstem nuclei > efferent nerves > neuromuscular junction > muscles/myopathy
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Lesion: brainstem (infarct, mass), efferent nerves (MND, GBS), NMJ (myaesthenia gravis), myopathies (rare bulbar myopathies)
The more likely scenario however is that you are not sure of the exact neuroaxis or lesion. In this case, this framework stills help you as it gives you a structure to logically discuss differentials, rather than throwing buzz words around in no particular order.