Parkinson's disease and parkinsonism Flashcards
Movement disorders - where is the problem in ‘pyramidal’ or ‘upper motor neurone’ disorder? what does this result in?
Problems with corticospinal/pyramidal tract
Pyramidal weakness Spasticity
Movement disorders - where is the problem in hyperkinetic movement disorder?
problem in the basal ganglia
Dystonia Tics Myoclonus Chorea Tremor
movement disorders - where is the problem in hypokinetic movement disorder?
parkinsonism
-lack of dopamine in the basal ganglia
ataxia - where is the problem?
cerebellum
What is the aetiology of parkinson’s disease?
sections through brainstem reveals loss of the normally dark pigment in the substantia nigra and locus coeruleus
pigment loss correlates with dopaminergic cell loss neurohistological landmark of PD are Lewy bodies
usually an asymmetric disorder
Describe the tremor in parkinson's disease -what is it like? -what does it affect? -when is it present? -
Involuntary, repetitive, rhythmic sinusoidal movement usually affecting one or more limbs
Primarily affects hands, may involve upper/lower limbs, less frequently jaw and lips, never head or neck Pill-rolling in the hands, or finger flexion-extension or abduction/adduction Present at rest, exacerbated by anxiety or stress Improves/disappears on action Typically reappears after few sec when arms held outstretched Tremor frequency in low to mid range (3-6hz) with varying amplitude Can observe tremor while patient is focused on a particular mental task e.g. counting backward
Describe the rigidity in parkinson’s disease
- what is it like?
- what is cogwheel rigidity?
- how can rigidity be accentuated?
Increase in muscle tone in parkinson’s disease is relatively constant throughout the range of movement: lead pipe rigidity
No increase with higher mobilising speed (distinguishing it from spasticity) Cogwheel rigidity is a consequence of the tremor of parkinsons disease being superimposed on background of lead-pipe rigidity Rigidity in one arm can be accentuated by asking the patient to lift and lower the contralateral arm repeatedly at the same time Positive froments manouvre
Describe the bradykinesia found in parkinson’s disease
- what is it like?
- what is micrographia
- how can lack of spontaneous movement manifest?
Slowness of movement with progressive loss of amplitude or speed during attempted rapid alternating movement of body segments
Assessed by foot tapping/opening and closing hand, quickly and widely as poss. Particular difficulty with complex motor tasks (micrographia) Smaller hand writing Lack of spontaneous movement nay manifest: Poverty facial expression/mask-like face and eye-blinking - hypomimia Difficulty changing position Quiet/monotonous speech - hypophonia Abnormal gait and stance
Describe the gait seen in parkinson’s disease
- posture
- what is particularly difficult?
- what are steps like?
Flexed or stooped posture
In some cases extreme anterior truncal flexion - camptocormia Unable to maintain a normal stance in response to pressure Initiation of walking may be difficult – freezing Turning may be difficult Patients may use trick such as deliberately stepping over a walking stick to change direction Steps are small and shuffling Normal arm swing on walking is lost Festination – very fast succession of steps and difficulty stoppping
Other motor symptoms in parkinsons disease:
- what kind of gaze is difficult?
- what is difficult to do in the GI system?
- is there any MSK manifestations?
- is muscle power/reflexes/sensations/plantar response affected?
Mild impairment of upgaze, eyelid tremor
Difficulty swallowing, including saliva Many patients have a frozen shoulder Muscle power/reflexes/sensations/plantar response is normal
What are the non-motor symptoms found in parkinson’s disease? 7
Depression – chemical depression
Visual hallucinations – esp. at night Psychosis – worsening hallucinations and delusions may escalate Dementia – common feature of advanced parkinsons, >80% of pt.s after 20years Insomnia Autonomic symptoms – greasy skin, constipation, bladder disturbance, erectile dysfunction Anosmia
Parkinson’s disease epidemiology:
- is it common?
- male to female?
- what increases the probability of a genetic cause?
Second most common neurodegenerative disorder after AD
!- 2% over 60- 65’s affected 0.3% population male to female 3:2 annual incidence rates 8.6-19 per 1000 due to ageing population, prevalence and socioeconomic burder expected to rise exponentially early onset (below 40years) increases probability of genetic cause
What are the risk factors for parkinson’s disease?
old age = strongest risk factor
28 distinct chromosomal regions have been linked to PD 6 of these contain genes that conclusively cause monogenetic PD monogenetic PD accounts for 30% familial and 3-5% sporadic cases pesticide exposure and +ve FH are other risk factors possible protective role of NSAIDs and high uric acid levels smoking has a protective affect therefore etiology is genetically heterogeneous and multifactorial – genes, modifying effects by susceptible alleles and environmental factors
Should you see sensory/pyramidal/cerebellar signs in parkinson’s disease?
no
What are the investigations for parkinsons disease?
To rule out treatable conditions of asthenia: hypothyroid, anaemia
Structural brain imaging Possibly dopamine functional imaging PET with fluoro-dopa (limited avail. And high cost) DAT-SPECT These are unable to distinguish PD from other causes of parkinsonism, but should be normal in essential tremor, dystonic tremor, psychogenic parkinsonism Positive levodopa challenge (or s.c. apomorphine) Genetic testing if appropriate
