1. Ed Hutchison and Paul Swift
Localising the lesion P
Ed Hutchison and Paul Swift

2. Aims Approach UMN vs. LMN Spinal tracts Cerebellum Cerebrum
Visual lesions
Cases P

3. Approach to localising the lesion
Be systematic! E
…A patient presents with arm weakness…

4. Muscle – e.g. diabetic myopathy
NMJ – e.g. myasthenia gravis E
Peripheral nerve – e.g. GBS
Spinal cord – e.g. cord compression
Cerebrum – e.g. Stroke

5. Timeline
Immediate
Intermediate
Long-term E

6. UMN vs. LMN
??? P

7. UMN vs. LMN UMN LMN Hyperreflexia Hyporeflexia Hypertonia Hypotonia
Clonus
Muscle wasting
No muscle wasting/fasciculation
Fasciculation
Plantars upgoing (lower limbs)
Plantars downgoing (lower limbs) P

8. Pyramidal vs. Extrapyramidal
Weakness
Tremor
Spasticity
Chorea
Pronator drift
Hemiballismus
Loss of skilled movement
Athestosis
Hyperreflexia
Dystonia
Change in tone/tendon reflexes
Plantars upgoing
Loss of abdominal/cremasteric reflex
Extrapyramidal system: basal ganglia P

9. Clonus
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10. Facial nerve palsies Bulbar vs. pseudobulbar
Pseudobulbar = UMN of CN IX-XII
Spastic tongue
Sparing of forehead
Bulbar = LMN of CN IX-XII
Tongue wasting/fasciculation
Affects all facial muscles E

11. E

12. The tracts
Dorsal column ?
Corticospinal ? P ?
Spinothalamic

13. Lateral Spinothalamic
Pain and temperature
Decussates at the level of the spinal cord P

14. Anterior Spinothalamic
Crude touch and pressure
Decussates at the level of the spinal cord P

15. Dorsal columns Discrimination, proprioception, vibration.
Crosses at the medulla. P
Subacute combined degeneration of the cord,
Tabes dorsalis,
Spinal trauma.

16. Corticospinal Tracts
Descending motor tracts.
Cross at the medulla. P

17. Brown-Sequard P

18. Brainstem CN IX-XII Symptoms/signs: Dysarthria Dysphagia/drooling
Tongue weakness
Absent palatial movement E

19. Cerebellum
Cerebellospinal tracts
Ipsilateral – DO NOT CROSS E

20. Blood Supply E

21. D A N I S H Cerebellar Signs – dysdiadochokinesia
– ataxia (truncal and limb)
– nystagmus
– intention tremor
– slurred speech
– hypotonia E

22. Causes
Alcohol
Thiamine deficiency
CVA
Friedreich’s ataxia
Etc etc… E

23. The Homunculus P

24. Cerebral Artery TerritoriesP

25. P

26. ? Circle of Willis Anterior cerebral artery Middle cerebral artery
Posterior cerebral artery
Basilar artery E
Vertebral artery
A = ?
Anterior spinal artery
B = ?

27. Speech Centres
arcuate fasciculus  conduction aphasia E

28. Tono man E

29. Broca’s dysphasia E

30. Stroke Syndromes TACS – all 3 PACS – 2 of 3 LACS POCS
Hemiplegia/hemisensory loss
See left
No visual field defect
Bilateral motor or sensory
Visual field disturbance
Pure motor
Conjugate eye movement disturbance
Disturbance in higher function – e.g. dyphasia/dysphagia
Pure sensory
Cerebellar dysfunction
Sensory-motor
Hemiplegia or cortical blindness
Ataxia E

31. Visual Defects Ipsilateral blindess Bilateral hemianopia
Left homonymous hemianopia
Left superior quadrantanopia P
Left homonymous hemianopia with macular sparing

32. Cases

33. Case 1
57 year old man complaining of weakness and altered sensation in upper limbs and lower limbs
Loss of sensation from shoulders and down, urinary incontinence
On Examination:
CN intact
Upper limbs weakness, hypotonia, reduced reflexes
Lower limbs spasticity, hyper-reflexia and Babinski +ve, reduced sensation from shoulders down
C-spine C4 E

34. Case 2
85 year old man with long standing (20yr) history of balance problems worse in the dark.
Gait is high stepping
On Examination:
CN intact
Motor intact
Loss of proprioception with +ve Romberg’s test
Tabes dorsalis (dorsal columns) P

35. Case 3
23, female presents to her GP with a 2 week history of bilateral leg weakness having started with pins and needles and numbness in her hands and feet. She has had a few days of urinary incontinence which has resolved. 2 years ago she had an episode of blurred vision and pain in the right eye which lasted a month and fully resolved E

36. Case 4
56 male
6 month history of progressive weakness of his right hand. Also had problems with swallowing and has choked whilst eating on several occasions
o/e he has wasting of his upper and lower limbs and some fasciculation's were noted his right plantar was up going and his reflexes were generally brisk P

37. Things we’ve not had time to cover
Peripheral neuropathies
Motor neurone
Parkinson’s
Huntington’s
GBS
Myasthenia gravis E

38. Peripheral Neuropathies
A – alcohol
B – B12 deficiency
C – CKD
D – drugs/diabetes
E – every vasculitis P