Tremors - Orthostatic, Essential, Dystonic, Cortical, Functional, Enhanced Physiologic, Psychogenic

Question 1

Orthostatic tremor

• presentation
• investigations

Answer 1

50+

Fast tremor in legs and trunks when standing still
-unsteadiness, calf pain
Relieved by walking, sitting, supine

EMG confirmation

Question 2

Essential tremor

• epidemiology, pathophysiology
• presentation
• management

Answer 2

40+, familial
-thought to be a problem between the cerebellum and other parts of the brain => poor muscle coordination

Isolated bilateral upper limb action tremor
No other neuro signs
\:) alcohol and rest
\:( stress, caffeine, some medications
-slow progression

Treatment not needed if mild
1st line - propanolol + avoid triggers
2nd line - primidone (AED) or BZ
Botox, DBS for medically refractory

Question 3

Dystonic tremor syndrome

• presentation
• management

Answer 3

Tremor + dystonia
Adults - generally focal
Children - multiple body parts involved

Arises after specific movements/tasks, affecting same muscle groups => irregular amplitude
:) antagonistic gestures, rest
Head, arm tremor

Lifestyle

• avoid mv that trigger dystonia
• stress management, rest, relaxation
• antagonistic muscle use

Medical

• trihexylphenidyl
• DBS of GPI

Question 4

Cortical tremor

• causes
• presentation
• investigations

Answer 4

Genetic - mitochondrial
Most common cause - drugs (fluoxetine, clozapine, gabapentin)

Short duration bursts => irregular, jerky movements

EMG

Question 5

Functional tremor syndrome

-presentation

Answer 5

Distractibility
Frequency entrainment
Antagonistic muscle coactivation

Question 6

Investigations to consider for tremors

Answer 6

EMG - presence of tremor, frequency and rhythm

Structural imaging - MRI, CT for lesions, metabolic disorders (basal ganglia, cerebellum)
-decreased metabolic activity in FDGPET (PD vs ET)

Receptor imaging - dopamine deficiency (PD vs ET)

Serum, tissue markers - metabolic blood tests (Cu in Wilsons, hyperthyroidism

Question 7

Characterisation of tremor

Answer 7

Anatomical distribution
-focal or generalised

Activation condition

• rest
• action (kinetic, postural, isometric)

Frequency
-cortical (fastest)

Associated signs

• isolated tremor
• combined with dystonia/rigidity/bradykinesia/systemic disease signs

Question 8

Enhanced physiologic tremor

Answer 8

Normally, we all have a low amplitude fine tremor to help us maintain a posture or movement

Enhanced when a specific posture is maintained

Tremor improves after cause addressed

Question 9

Psychogenic tremor

Answer 9

Can involve any body part, most commonly the extremities
Sudden onset

Combination of postural, action, resting tremor

Decreases with distraction, associated with psychosomatic