title: The clinical phenomenology and associations of trick maneuvers in cervical dystonia.
abstract: Sensory trick is an unusual clinical feature in cervical dystonia that attenuates disease symptoms by slight touch to a specific area of the face or head. Using a semi-quantitative questionnaire-based study of 197 patients with idiopathic cervical dystonia, we sought to determine probable pathophysiologic correlates, with the wider aim of examining its eventual clinical significance. The typical sensory trick, i.e., light touch, not necessitating the use of force leading to simple overpowering of dystonic activity, was present in 83 (42.1 %) patients. The vast majority of the patients required a specific sequence of sensorimotor inputs, including touch sensation on the face or different areas of the head, and also sensory and motor input of the hand itself. Deviations often led to a significant decrease in effectiveness and lack of expected benefit. Moreover, patients able to perform the maneuver reported compellingly higher subjective effect of botulinum toxin treatment (median 7 vs. 5 on a scale of 0-10; p < 0.0001) and lower depression score (median 10 vs. 14 on the Montgomery Åsberg Depression Rating scale; p < 0.001). Overall, the results point to marked disruption of sensorimotor networks in cervical dystonia. The mechanism of the sensory trick action may be associated with balancing the abnormal activation patterns by specific sensorimotor inputs. Its presence may be considered a positive predictive factor for responsiveness to botulinum toxin treatment.
authors.affiliation: Central European Institute of Technology, CEITEC MU, Behavioral and Social Neuroscience Research Group, Masaryk University, Brno, Czech Republic. pvlfilip@gmail.com.|First Department of Neurology, Faculty of Medicine, Masaryk University and St. Anne's Teaching Hospital, Pékařská 53, 656 91, Brno, Czech Republic. pvlfilip@gmail.com.
authors.forename: Pavel
authors.identifier: http://orcid.org/0000-0001-5656-5164
authors.initials: P
authors.lastname: Filip
authors.affiliation: First Department of Neurology, Faculty of Medicine, Masaryk University and St. Anne's Teaching Hospital, Pékařská 53, 656 91, Brno, Czech Republic.
authors.forename: Rastislav
authors.initials: R
authors.lastname: Šumec
authors.affiliation: First Department of Neurology, Faculty of Medicine, Masaryk University and St. Anne's Teaching Hospital, Pékařská 53, 656 91, Brno, Czech Republic.
authors.forename: Marek
authors.initials: M
authors.lastname: Baláž
authors.affiliation: Central European Institute of Technology, CEITEC MU, Behavioral and Social Neuroscience Research Group, Masaryk University, Brno, Czech Republic.|First Department of Neurology, Faculty of Medicine, Masaryk University and St. Anne's Teaching Hospital, Pékařská 53, 656 91, Brno, Czech Republic.|Department of Neurology, School of Medicine, University of Minnesota, Minneapolis, USA.
authors.forename: Martin
authors.initials: M
authors.lastname: Bareš
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010812:Physical Stimulation; D011795:Surveys and Questionnaires; D014103:Torticollis; D014110:Touch
keywords: Botulinum toxin; Cervical dystonia; Sensory trick; Treatment effectiveness