Pattern recognition

Question 1

What are the features of an upper motor neuron pattern?

Answer 1

Increased tone, brisk reflexes, pyramidal/corticospinal pattern of weakness i.e. weak extensors in the arms, weak flexors in the legs

Question 2

What are the features of a lower motor neuron pattern?

Answer 2

Wasting, fasciculation, decreased tone, decreased or absent reflexes, flexor plantars/Babinski sign

Question 3

What are the features of muscle disease?

Answer 3

Wasting (usually proximal), decreased tone, decreased or absent tendon reflexes

Question 4

What are the features of neuromuscular junction injury?

Answer 4

• Fatiguable weakness, normal or decreased tone, normal tendon reflexes
• No sensory symptoms

Question 5

What are the features of functional weakness?

Answer 5

No wasting, normal tone, normal reflexes, erratic power, non-anatomical loss

Question 6

What can cause UMN lesions?

Answer 6

• Acute stroke syndrome, space occupying lesions and spinal cord problems
• Can usually be determined by body segments involved and accompanying signs e.g, hemispheric - contralateral pyramidal weakness in face, arm and leg

Question 7

What can cause LMN lesions in the anterior horn cells?

Answer 7

Occurs with motor neuron disease, spinal muscular atrophy, lead poisoning, poliomyelitis

Question 8

What can cause LMN lesions in the peripheral nerves and how does this present?

Answer 8

• Symmetrical polyneuropathy with weakness and sensory symptoms - frequent complication of diabetes. Other causes include alcohol or metabolic insults as well as heritable disorders
• Mononeuropathy as a result of nerve compression (carpal or tarsal tunnel syndrome, ulnar neuropathy, radial neuropathy) or mononeuritis multiplex which occurs in the context of diabetes or vasculitis

Question 9

What can cause neuromuscular junction injury and how does it present?

Answer 9

• Presents with purely fatiguable motor symptoms
• Occurs in acetylcholine receptor antibody mediated myasthenia gravis, inhibition of acetylcholinesterase by organophosphate poisoning, or interference with presynaptic calcium channel function in Lambert-Eaton paraneoplastic syndrome

Question 10

What can cause muscle disorders and how do they present?

Answer 10

• Often symmetrical, often proximal, very wide differential diagnosis
• Inflammatory e.g. polymyositis, vasculitis
• Endocrine e.g. hypothyroidism, Cushing’s
• Drugs and toxins e.g. alcohol, cocaine, steroids
• Infections e.g. HIV, pyomyositis, toxoplasmosis
• Rhabdomyolisis

Question 11

What nerve and nerve root supplies the deltoid muscle? What movement does the deltoid muscle control?

Answer 11

Axillary nerve, C5 nerve root, controls shoulder abduction

Question 12

What nerve and nerve root supplies the triceps muscle? What movement does the triceps muscle control?

Answer 12

Radial nerve, C7, controls elbow extension

Question 13

What nerve and nerve root supplies the iliopsoas muscle? What movement does the iliopsoas muscle control?

Answer 13

Femoral nerve, L1, 2, controls hip flexion

Question 14

What nerve and nerve root supplies the hamstring muscles? What movement do the hamstring muscles control?

Answer 14

Sciatic, S1, controls knee flexion

Question 15

What nerve and nerve root supplies the peroneal muscles? What movement do the peroneal muscles control?

Answer 15

Common peroneal and sciatic, L4, 5, controls ankle dorsiflexion

Question 16

What nerve and nerve root supplies the extensor hallucis longus muscle? What movement does the extensor hallucis longus muscle control?

Answer 16

Common peroneal, L5, controls great toe dorsiflexion

Question 17

What nerve roots innervate the ankle reflex?

Answer 17

S1, 2

Question 18

What nerve roots innervate the knee reflex?

Answer 18

L3, 4

Question 19

What nerve roots innervate the biceps reflex?

Answer 19

C5, 6

Question 20

What nerve roots innervate the triceps reflex?

Answer 20

C7, 8

Question 21

What does a stocking (and later glove) distribution of sensory loss suggest?

Answer 21

Length dependent neuropathy

Question 22

What does a sensory level pattern of sensory loss suggest?

Answer 22

Spinal cord lesion

Question 23

What does a hemianaesthesia suggest?

Answer 23

Contralateral cerebral lesion, or with no other signs a non-organic disorder

Question 24

What does dissociated sensory loss suggest?

Answer 24

Loss with lost spinothalamic (pain/temperature) but preserved dorsal column (fine touch, vibration, proprioception) suggests hemicord damage (Brown-Sequard syndrome, syringomyelia, anterior spinal artery syndrome)

Question 25

What are cerebellar signs?

Answer 25

* Cerebellar gait is broad-based and unsteady * Intention tremor/ataxia is assessed in the arms by **finger-nose test** and in the legs by **knee-heel** testing * Dysdiadochokinesis * Nystagmus and dysarthria are additional features of cerebellar disorders * **DANISH** - dysdiadochokinesis, ataxia, nystagmus, intention tremor, speech problems, hypotonia

Question 26

What are extrapyramidal symptoms/Parkinsonism?

Answer 26

* **Bradykinesia, rigidity, resting tremor,** impaired gait and posture * Hypomimia * Hypophonia * Reduced arm swing, stooped posture, small steps, **festination, turning en bloc** * Impaired postural reflexes * **Asymmetry in PD**, symmetry in drug induced or atypical PD

Question 27

What does the frontal lobe control?

Answer 27

Generates novel strategies and has executive functions. It enables self-criticism and trying again. The prefrontal cortex connects extensively to other association cortices, basal ganglia, limbic system, thalamus and hippocampus

Question 28

What are some signs associated with frontal lobe dysfunction?

Answer 28

**Personality dysfunction**, paraparesis, paratonia, grasp reflex, seizures, incontinence, visual field defects, **expressive dysphasia (Broca's area), anosmia** (olfactory pathway)

Question 29

What are some signs associated with temporal lobe dysfunction?

Answer 29

**Memory dysfunction**, agnosia, **receptive dysphasia (Wernicke, dominant hemisphere),** visual field defects **(superior quadrantopia)**, auditory dysfunction, limbic dysfunction, temporal lobe epilepsy

Question 30

What are some signs associated with parietal lobe dysfunction?

Answer 30

Visual field defect **(inferior quadrantopia**) sensory dysfunction, **Gerstmann's syndrome** (Dysgraphia, left-right disorientation, finger agnosia, acalculia), **dyspraxia**, inattention, denial

Question 31

What is used to treat Parkinson's disease?

Answer 31

**Levodopa** - crosses the BBB while dopamine does not, levodopa is then converted into dopamine in the brain

Question 32

What drug is often used concomitantly with levodopa when managing PD?

Answer 32

**COMT inhibitors** - levodopa can be broken down by catechol-O-methyltransferase (COMT) so COMT inhibitors such as entacapone are often used

Question 33

What are the cardinal features of PD?

Answer 33

* **Resting tremor, rigidity, bradykinesia and postural instability** * PD is usually asymmetrical * Postural instability leading to falls occurs relatively late in the clinical course of PD

Question 34

What are the cardinal features of multiple sclerosis (MS)?

Answer 34

* **Visual compromise, stiffness and weakness** * MS can have lesions on MRI without clinical compromise directly related to those lesions * **Oligoclonal bands in the CSF** are also found in other conditions * The symptoms of MS can worsen with fever

Question 35

Describe the clinical presentation of motor neuron disease

Answer 35

* Progressive muscular atrophy accounts for 10% although most eventually develop UMN signs * Primary lateral sclerosis is a pure upper motor syndrome * Usually it is a **mix of UMN and LMN abnormalities in the absence of sensory disturbances** * Cognitive impairment may be part of the presentation * Ask about cramps, fasciculations, foot drop, family history and behavioural changes * **Frontotemporal dementia**

Question 36

How is imaging used to investigate stroke?

Answer 36

* **MRI T1/2** and FLAIR images to identify **old lesions** and lesions of non-vascular origin * Diffusion weighted images to identify new ischaemic lesions * **T2 to identify bleeds** and microbleeds * Perfusion weighted images may be useful to identify brain areas at risk of ischaemia * **CT brain - hyperintensities**

Question 37

What are the clinical features of lacunar syndrome?

Answer 37

* No visual field defect, no new higher cortical or brainstem dysfunction * **Pure motor hemiparesis**, or **pure sensory deficit** of one side of the body, or **sensorimotor hemiparesis or ataxic hemiparesis** * At least **2 of the 3 areas (face, arm, leg**) should be involved in its entity

Question 38

What are the clinical features of posterior circulation syndrome?

Answer 38

**Cranial nerve palsy**, unilateral or bilateral motor or sensory deficit, disorder of **conjugate eye movements**, **cerebellar dysfunction**, **homonymous hemianopia**, cortical blindness

Question 39

What are the clinical features of total anterior circulation syndrome?

Answer 39

**Hemiplegia and homonymous hemianopia contralateral to the lesion** and either aphasia or visuospatial disturbances +/- sensory deficit contralateral to the lesion

Question 40

What are the clinical features of partial anterior circulation syndrome?

Answer 40

* One or more of **unilateral motor or sensory deficit, aphasia or visuospatial neglect** (with or without homonymous hemianopia) * Motor or sensory deficit may be less extensive than in lacunar syndrome