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

Question 1

Tremor history key questions

Answer 1

Involuntary, rhythmic, oscillatory movement of a body part

Age of onset
Temporal evolution

Bodily distribution
Activation conditions - rest, action (kinetic, postural, isometric)
Tremor frequency - cortical (fastest)

Associated signs
-isolated tremor
-combined with dystonia/rigidity/bradykinesia/systemic disease signs

Anatomical distribution
-focal or generalised

FHx or sporadic

Question 2

Tremor, investigations to consider

Answer 2

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 3

Activation conditions of a tremor?

Answer 3

Only at rest

Action

kinetic => simple/intention/task specific?
postural => position independent/dependent
isometric tremor

Question 4

Orthostatic tremor

presentation
investigations

Answer 4

50+

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

EMG confirmation

Question 5

Essential tremor

epidemiology, pathophysiology
presentation
management

Answer 5

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 6

Dystonic tremor syndrome
-presentation
-management

Answer 6

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 7

Cortical tremor
-cause
-presentation
-investigations

Answer 7

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

Short duration bursts => irregular, jerky movements

EMG

Question 8

Functional tremor syndrome
-presentation

Answer 8

Distractibility
Frequency entrainment
Antagonistic muscle coactivation

Question 9

Enhanced physiologic tremor

Answer 9

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 10

Psychogenic tremor

Answer 10

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

Combination of postural, action, resting tremor

Decreases with distraction, associated with psychosomatic