Functional (Psychogenic) Dystonia
Functional (psychogenic) neurological disorders are common throughout neurological practice, and functional movement disorders (FMDs) form a considerable proportion of these cases. In this chapter, we will consider the entity of functional (psychogenic) d
- PDF / 249,812 Bytes
- 13 Pages / 439.37 x 666.14 pts Page_size
- 57 Downloads / 212 Views
Functional (Psychogenic) Dystonia Antonella Macerollo and Mark J. Edwards
Functional (psychogenic) neurological disorders are common throughout neurological practice, and functional movement disorders (FMDs) form a considerable proportion of these cases. In this chapter, we will consider the entity of functional (psychogenic) dystonia.
8.1
Terminology
A number of different words can be used to describe the broad topic of this chapter. The word used for centuries – hysteria – has now almost completely been abandoned given its connotations that the source of the problem is in the uterus and its lay use as an insulting term [1, 2]. However, one of the most eminent movement disorder specialists of recent times, David Marsden, asserted that neurologists “have clung on to hysteria because its modern roots sprang from neurology” [3]. The term “psychogenic” is the one in most common usage among movement disorder physicians and is one of a number of terms (conversion disorder, somatization, psychosomatic) that suggest a primary (even sole) role for psychological factors in the genesis
A. Macerollo • M.J. Edwards (*) Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, Queen Square, London, UK e-mail: [email protected] © Springer-Verlag Wien 2015 P. Kanovsky et al. (eds.), Dystonia and Dystonic Syndromes, DOI 10.1007/978-3-7091-1516-9_8
101
102
A. Macerollo and M.J. Edwards
of these movement disorders [4]. However, epidemiological studies fail to find the expected high rates of psychological trauma or distress in these patients [5]. In a survey of members of the movement disorder society reported by Espay et al., only 18 % of specialists used the presence of psychological disorder to make the diagnosis, and, interestingly, psychiatrists often sent patients to neurologists clarifying the diagnosis [6]. In place of these terms and other terms that define the disorder by saying what it is not (nonorganic, medically unexplained), it has recently been suggested that the historical term “functional” is the most appropriate [7]. It is certainly a term which is more acceptable to patients than many of the alternatives [8]. There are arguments to support the use of other terms, but while acknowledging these, we will use the term “functional” in this chapter [9]. In doing so, we seek to define these disorders by positive clinical characteristics as movement disorders that are significantly altered by distraction of attention or nonphysiological maneuvers (including dramatic placebo effects) and which are incongruent with movement disorders known to be caused by neurological disease.
8.2
Epidemiology
Functional neurological symptoms are very common, accounting for 16 % of the newly referred outpatients attending neurology clinics [10], and are the second most common issue for neurological outpatient consultation. The most common functional neurological symptoms are nonepileptic attacks and functional weakness [11]. Functional movement disorders (FMDs) consti
Data Loading...
