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1. You are teaching a group of medical students basic clinical skills. Which one of the following statements is true?

A. Extrapyramidal syndromes characteristically produce an upper motor neurone pattern
B. Fasciculation of the tongue is an upper motor neurone feature of motor neurone disease
C. Lesions of peripheral nerves are usually upper motor neurone in type
D. Lower motor neurone lesions cause ankle clonus
E. Upgoing plantar responses and absent ankle jerks imply both upper and lower motor neurone lesions

Answer: E

This seemingly incompatible combination seen in conditions in which both upper and lower motor neurone lesions are present. These include advanced B12 deficiency and perhaps most commonly combined lumbar spondylosis and cervical myelopathy. While MND could, at least in theory, produce this pattern, it would not be characteristic. Remember that upper motor neurone lesions (that is lesions above the dorsal column cell or cranial nerve nucleus involve the pyramidal (corticospinal) tracts and produce spastic tone, increased reflexes, a characteristic pattern of weakness and sometimes ankle clonus. Plantar responses will be extensor. In contrast lower motor neurone lesions produce a flaccid tone, reduced reflexes and sometimes muscle fasciculation.

2. A right-handed male actor aged 66 presents with gradual deterioration of clarity in his speech. He has no problems with his teeth, pains in his mouth or associated neurological problems. Which is the single most likely site of his problem?

A. Bilateral upper motor neurone lesion of cranial nerves 1X and X
B. Left hemisphere

C. Lower motor neurone lesion of cranial nerves 1X and X
D. Midbrain
E. Right hemisphere

Answer: C

Motor neurone disease features high on the differential diagnosis here and careful assessment should be made of this patient’s swallowing and respiratory function. Dominant hemispheric lesions would be expected to produce dysphasia (not as in this case a dysarthria) and since the 1X and X nerve nuclei are below the level of the midbrain, a lesion at this site would not produce a LMN weakness. A bilateral corticospinal lesion, however, will produce (so called) ‘Pseudobulbar palsy’—the commonest causes of which are motor neurone disease and cerebrovascular disease. These are almost inevitably associated with other neuropsychiatric signs such as bilateral spasticity and emotional lability.

3. A 66-year-old man, known to have motor neurone disease presents with the gradual onset of breathlessness. Which is the single most helpful measure of respiratory function? [Show

A. Forced expiratory volume in 1 second (FEV1)
B. Forced vital capacity (FVC)
C. Forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC)
D. Oxygen saturation
E. Peak flow rate

Answer: B

Patients with MND may have weakness of the intercostal muscles and the diaphragm. Symptoms may vary from breathlessness to orthopnoea (the latter especially if there is diaphragmatic involvement). More non-specific symptoms include daytime drowsiness due to changes in sleep pattern caused by hypercapnia—this, as in other causes of hypercapnia, may produce a morning headache.FEV1 is an important measure but is of most use in obstructive airways disease. While the FEV1/FVC would probably show a restrictive pattern in MND, the information gained from the combination is of less use than the FVC alone. The FVC (or more correctly the VC) not only indicates severity but is also easy to measure serially. Oxygen saturation alone, while relevant, may be expected to be fairly normal even in relatively advanced disease due to the shape of the oxygen dissociation curve. Peak flow is not relevant in this context.

4. A man with motor neurone disease is prescribed riluzole for motor neurone disease. You see the patient regularly and have a ‘shared care’ arrangement for monitoring the therapy. Which one of the following blood tests requires regular monitoring? [Show Discussion]

A. Fasting glucose
B. Full blood count
C. Liver function
D. Renal function
E. Thyroid function

Answer: C

Assuming normal baseline hepatic function, LFTs should be checked every month for 3 months, every 3 months for a further 9 months and every year thereafter.

5. A male patient has type 2 respiratory failure secondary to advanced motor neurone disease. When discussing options with him which is the single most appropriate initial way of delivering respiratory support should he wish to stay at home? [Show Discussion]

A. Endotracheal tube
B. Iron lung
C. Mask
D. Non-invasive ventilation
E. Tracheostomy

Answer: D

These portable devices are available via specialized respiratory units and prolong life. Further details of these (and other palliative measures) from the motor neurone disease association. http://www.mndassociation.org/

6. Which one of the following statements is true when considering a peripheral neuropathy

A. Examination should include testing from distally to proximally in the legs
B. Feet and hands are usually equally affected
C. Hyper-reflexia is characteristic
D. Hypertension is among the common causes
E. Joint position sense is usually absent if there is disturbance of pinprick sensation

Answer: A

There are many causes of peripheral neuropathy (alcohol and diabetes being two of the most common). Testing is best done for a given modality by first comparing the feet with (say) the upper leg which is likely to be normal. If there is a reproducible difference, it is then helpful to go from distal to proximal to see where sensation changes. The legs are usually affected before the hands and if anything hyporeflexia would be the norm. Hypertension is not a recognized cause and joint position sense loss would characteristically be a dorsal column problem.

7. The photograph below illustrates a previously fit middle-aged man who is recovering from a problem which started acutely 3 weeks before. Which one of the statements below is true? (See Figure 1)

A. He has a left-sided lower motor neurone weakness
B. He has a right-sided lower motor neurone weakness
C. He has a left-sided upper motor neurone weakness
D. He has a right-sided upper motor neurone weakness

Answer: A

This is most likely to be due to a Bell’s palsy. If this were an upper motor neurone weakness, the eye would not have been so obviously affected due to bilateral innervations. He does not require imaging or for that matter neurological referral unless atypical. If the weakness is prolonged (or recovery incomplete), the patient may benefit from assessment in a specialist facial nerve clinic.