Functional motor disorders: mechanism, prognosis and treatment

Functional motor disorders (FMD) consist of tremor, jerky movements, altered posturing or weakness. They are characterized by specific factors in the history and neurological examination, pointing at their functional nature, like the influence of attention and distraction or incongruency with the anatomy. They are highly prevalent and often significantly impairing. This thesis discusses the pathophysiology, prognosis and treatment of FMD.
Part 1 describes that we found many similarities between groups of different functional motor symptoms. Many patients report severe fatigue, which correlates with impaired quality of life and subjective health ratings. This calls for more attention in clinical practice. A comparison between cortical myoclonus and functional jerky movements showed comparable percentages of depressive and anxiety symptoms. Pain is more prevalent in functional jerky movements. Two chapters investigating fMRI in FMS, confirm existing theories on the role of altered attentional processes, perception of body scheme and sense of agency.
Part 2 contains a review and a case-control study on the prognosis of FMS. It turns out symptoms did not resolve in a large part of the studied patients and misdiagnosis was low.
Part 3 summarized the literature on the treatment on FMD and contains a RCT to the effect of education and self-help on the internet compared to usual care. We did not find differences between groups on clinically relevant outcome measures. Patients did report high satisfaction with the intervention.