CLINICAL FEATURESA number of clinical characteristics are associated with FMDs
●Abrupt onset
●History of a precipitating event
●Fast progression to maximum symptom severity and disability
●Movement abnormality that is incongruent with organic disease (eg, bizarre, multiple, or difficult to classify)
●Inconsistency over time with variable amplitude, frequency, or distribution of the movement
●Ability to trigger or relieve the movement with unusual or nonphysiologic intervention (eg, trigger points on the body, application of a tuning fork)
●Decreased movement of the affected body part with distraction
●Increased movement of the affected body part during observation or examination
●Entrainment of movement (eg, tremor) to the frequency of repetitive movements
●Coactivation sign of antagonist muscles
●Deliberate slowness of movement
●Association with false (or “give-way”) weakness, sensory loss, and pain
●Functional disability out of proportion to exam findings
●Unresponsiveness to drugs for organic movement disorders
●Responsiveness to placebo drugs and suggestion
The main FMD syndromes are functional tremor, functional dystonia, functional gait, functional myoclonus, and functional parkinsonism. These are reviewed in the sections below.
Jo-AnneRamplings 