Movement Disorders

• What needs to be intact for normal movement?

  Intact cortex all the way to neuromuscular junction

  Movement is fine-tuned by the cerebellum & basal ganglia -> fluid movement
• What is hypokinesia?

  Too little movement
• What is hyperkinesia?

  Too much movement
• Movement disorders usually refer to problems with fluid movement (basal ganglia, cerebellum & metabolic).
• What is needed for a diagnosis of Parkinsonism?

  MUST have bradykinesia

  AND 1 of;

  • rigidity
  • rest temor (4-6 Hz)
  • postural instability
• What are the causes of Parkinsonism?

  Idiopathic Parkinson's disease

  Vascular Parkinsonism

  Medications that block dopamine

  Rarer causes

  • Dementia with Lewy Bodies
  • Parkinson's plus syndromes (PSP, MSA)
• Give some examples of hyperkinesia.

  Tremor

  Chorea

  Dystonia

  Myoclonus

  Tics
• What is a tremor?

  Rhythmical, sinusoidal, alternating movement

  Different types -> aids in diagnosis
• What are the different types of tremor?

  Postural

  Action/kinetic

  Rest
• What is a postural tremor?

  Tremor on holding a posture (e.g. outstretched hands)

  Can be;

  • essential tremor
  • thyrotoxicosis
  • salbutamol
• What is an action/kinetic tremor?

  Tremor upon movement

  Due to;

  • cerebellar dysfunction (stroke, tumour, genetic, alcohol etc.)
• What is a rest tremor?

  Tremor at rest (may require distraction to elicit)

  Due to;

  • Parkinsonism
• What is chorea?

  Dance-like, unpredictable, flowing movements moving from one area to another
• What is ballism?

  Chorea that affects proximal joints -> movements are large & flinging
• What is the pathophys behind chorea?

  Damage to striatum -> loss of indirect pathway -> more direct compared to indirect -> more ‘go’ signals -> hyperkinesia (chorea)
• What are the causes of chorea?

  Any structural lesion of striatum (e.g. stroke, tumour, etc)

  Neurodegenerative/genetic (Huntington's chorea, Wilson's disease)

  Immune mediated (Sydenham's chroea)

  Drug induced (Levodopa induced dyskinesia)
• What is dystonia?

  Sustained or intermittent muscle contraction -> abnormal postural movement

  Can be repetitive or task specific

  Can be painful
• What are the causes of dystonia?

  Idiopathic

  Genetic

  Part of other conditions (e.g. PD)

  Structural lesions (trauma, tumour, stroke)

  Immune mediated

  Post infectious

  Drugs (antipsychotics, antiemetics)
• What is myoclonus?

  Jerky, shock-like movement

  Can be picked up by EMG
• What are some causes of myoclonus?

  Normal

  Medication induced

  Epilepsy

  Dementia
• What is a tic?

  Involuntary movement, usually brief

  Can be movement or sound

  Can be simple of complex

  Can be suppressed for short periods of time

  Often sterotypes
• What are the causes of tics?

  Tourette's syndrome (most common)

  Huntington's chorea

  Wilson's disease

  Some medication
• What can Wilson's disease present with?

  Parkinsonism

  Chorea

  Dystonia

  Psychiatric issues

  Liver disease
• What is shown in the image?

  Wilson's Disease

  
• What is a functional movement disorder?

  Abnormal movement due to the nervous system not working properly without an underlying neurological disease
• What can functional movement disorders cause?

  Gait abnormalities

  Tremor

  Jerking movements

  Mimic dystonia
• Parkinsonism -> effect on pathways

  In Parkinsonism, substantia nigra is damaged -> doesn’t stimulate direct pathway and/or inhibit the indirect pathway -> more indirect than direct -> less movement -> movements become smaller & slower (bradykinesia)
• What are the general signs & symptoms of Parkinsonism?

  Stooped posture

  Masked face

  Back rigidity

  Forward tilt of trunk

  Reduced arm swing

  Flexed elbows & wrists

  Tremor in legs

  Hand tremor

  Slighlty flexed hips & knees

  Shuffling, short stepped gait

  
• Which basal ganglia pathway is shown?

  Direct pathway

  
• Which basal ganglia pathway is shown?

  Indirect pathway

  
• Fill in the blanks

  A) Striatum

  B) Caudate nucleus

  C) Putamen

  D) Globus pallidus

  E) Subthalamic nucleus

  F) Substantia nigra