Functional Movement Disorder; Importance of Proper Diagnosis and Treatment: A Case Report

Abstract

Background: Dystonia is a common movement disorder with a wide range of aetiologies. Delays in the identification and initiation of effective treatments should be minimized to improve patient pain and optimize outcomes. This case report aims to underscore the successful treatment of chronic dystonia with the use of mood-modifying serotonin and norepinephrine reuptake inhibitors (SNRI), and encourage clinicians to consider a diagnosis of functional (psychogenic) movement disorder in patients with dystonia that is refractory to usual treatment. Case Report: This case report describes a 40-year-old woman who presented to a chronic pain clinic for pain related to cervical dystonia with associated head tremor. Her symptoms were refractory to nearly a decade of quarterly botulinum toxin injections. Based on careful evaluation of the patient’s history, a normal neurological examination, increased Generalized Anxiety Disorder Scale (GAD-7), Patient Health Questionnaire-9 (PHQ-9), and Injustice Experiences Questionnaire (IEQ) scores, and unsuccessful symptom management with botulinum toxin A, a diagnosis of functional movement disorder (FMD) was made. Low-dose Cymbalta was initiated. The patient achieved near complete symptom remission and resolution of her chronic pain within 2 months and achieved near complete resolution in 2 years. Conclusion: A diagnosis of FMD should be considered in all patients with dystonia, but especially in patients who respond inadequately to botulinum toxin injections or other rehabilitation therapies. The treatment of comorbid psychiatric conditions can result in substantial benefits and remission from dystonia due to FMD.