Diagnosis Of Functional Movement Disorders Research Articles

Characteristics of two distinct clinical phenotypes of functional (psychogenic) dystonia: follow-up study.

The fixed dystonia phenotype was originally established as a prototype of functional dystonia. Nevertheless, in recent reports different functional dystonia phenotypes have been recognized with dystonic movement comprising phasic instead of tonic contraction. To examine clinical characteristic in all patients with dystonia who fulfilled the criteria for functional movement disorders irrespective of phenotype in an attempt to determine parameters of clinical presentations that might impact the disease progression pattern and outcome. Patients presented with dystonia features incompatible with organic disease without other features required for the diagnosis of functional movement disorders were analyzed and prospectively followed-up. The two-step cluster analysis was performed to obtain the subgroups of dystonia phenotypes. The two-step cluster analysis extracted two subgroup of patients. Patients of the first cluster (68.8%) presented with "mobile" dystonia (84.9%), of cranial/neck/trunk localization (90.9%), fluctuated clinical course (69.7%), with frequent additional movement or other functional neurological disorders (63.6%) during follow-up. In the second cluster (31.2%) all of the patients presented with "fixed" dystonia of extremities, and the clinical course was characterized by either the disease progression (60%), or continuous without improvement (26.7%), and rare occurrence of additional functional neurological disorders (13.3%). In terms of clinical and demographic features as well as pattern of disease progression there are two clinical phenotypes in patients with functional dystonia. Distinctive features of incongruence and inconstancy are characteristic for "mobile" functional dystonia subgroup of patients.

Personality disorders and somatization in functional and organic movement disorders

Psychiatric disturbances and somatizations are both criteria which support the diagnosis of functional movement disorders. It is unclear, however, whether these factors are helpful in differentiating functional and organic movement disorders. To address this issue, the Structured Clinical Interview for DSM-IV Axis I and II psychiatric disorders, the State-Trait Anxiety Inventory, the Beck Depression Inventory and the “somatization section” of the Dissociative Disorders Interview Schedule were administered to 31 functional movement disorder patients diagnosed, according to Fahn and Williams criteria and 31 sex- and age-matched control outpatients, with adult-onset dystonia. Axis I psychiatric diagnoses were similarly frequent in patients with functional and organic movement disorders. There was a trend to a greater frequency of personality disorders overall; when looking at individual personality disorders, there was no significant between-group difference. Depression and anxiety scores and mean number of somatizations per patient were also greater in the functional group. The number of somatic complaints significantly correlated with depression and anxiety scores. However, the presence of these disturbances in a proportion of patients with organic dystonia indicates that personality disorders and somatizations do not aid in distinguishing functional and organic movement disorders.

Chapter 31 - Functional facial and tongue movement disorders

Functional movement disorders (FMDs) affecting the eyelids, tongue, and other facial muscles are often underrecognized because their phenomenology has not been fully characterized. Nevertheless, these disorders are more common than previously thought. In this chapter we will discuss the phenomenology as well as the clinical and instrumental diagnosis of facial FMDs. Facial FMDs should be considered when a patient exhibits any combination of the following features: (1) fixed unilateral facial contractions, especially with lower lip, with or without ipsilateral jaw involvement, of maximal severity at onset; (2) inconsistent features such as changes in side and pattern during or between examination; (3) associated somatoform or nonphysiologic sensory or motor findings; (4) reduction or abolition of facial spasm with distraction; (5) response to suggestion or psychotherapy; (6) rapid onset and/or spontaneous remissions; and (7) normal neurologic examination. Supportive features are young age, female gender, and associated medical conditions such as depression, headaches, facial pain, fibromyalgia, or irritable-bowel syndrome. Finally, the differential diagnosis with the organic counterparts will be also addressed, particularly with respect to blepharospasm, oromandibular dystonia, and hemifacial spasm.