Functional (psychogenic) movement disorders - Clinical presentations.

Area of Science:

• Neurology
• Psychiatry

Background:

• Functional movement disorders are prevalent and disabling neurological conditions.
• Accurate diagnosis can be challenging, often relying on exclusion rather than positive findings.

Purpose of the Study:

• To outline key historical and physical examination features that support the diagnosis of functional movement disorders.
• To emphasize a diagnostic approach based on positive evidence rather than solely on exclusion.

Main Methods:

• Review of clinical features suggestive of functional movement disorders.
• Identification of specific diagnostic signs for various movement types (tremor, myoclonus, gait, dystonia).

Main Results:

• Positive historical clues include sudden onset, intermittent course, variability, trauma history, and secondary gain.
• Examination findings like distraction, suggestibility, tremor entrainment, complex myoclonus, and preserved balance in gait disorders are significant.
• Fixed dystonia is a notable sign suggestive of functional etiology.

Conclusions:

• Diagnosis of functional movement disorders should be based on positive historical and examination findings.
• Specific signs exist for different movement types, aiding in diagnosis.
• While anxiety and depression are common, they are not definitive diagnostic criteria.