Oromandibular Dystonia: A Clinical Examination of 2,020 Cases

Abstract

Objective: The goal of this study is to better characterize the phenotypic heterogeneity of oromandibular dystonia (OMD) for the purpose of facilitating early diagnosis.Methods: First, we provide a comprehensive summary of the literature encompassing 1,121 cases. Next, we describe the clinical features of 727 OMD subjects enrolled by the Dystonia Coalition (DC), an international multicenter cohort. Finally, we summarize clinical features and treatment outcomes from cross-sectional analysis of 172 OMD subjects from two expert centers.Results: In all cohorts, typical age at onset was in the 50s and 70% of cases were female. The Dystonia Coalition cohort revealed perioral musculature was involved most commonly (85%), followed by jaw (61%) and tongue (17%). OMD more commonly appeared as part of a segmental dystonia (43%), and less commonly focal (39%) or generalized (10%). OMD was found to be associated with impaired quality of life, independent of disease severity. On average, social anxiety (LSA score: 33 ± 28) was more common than depression (BDI II score: 9.7 ± 7.8). In the expert center cohorts, botulinum toxin injections improved symptom severity by more than 50% in ~80% of subjects, regardless of etiology.Conclusions: This comprehensive description of OMD cases has revealed novel insights into the most common OMD phenotypes, pattern of dystonia distribution, associated psychiatric disturbances, and effect on QoL. We hope these findings will improve clinical recognition to aid in timely diagnosis and inform treatment strategies.

Botulinum Toxin Therapy for Oromandibular Dystonia and Other Movement Disorders in the Stomatognathic System

“…The term 'oromandibular dystonia' was first introduced by Marsden in 1976 [72]. OMD is a focal type of dystonia characterized by contractions of the masticatory, lingual, pharyngeal, and/or muscles of the stomatognathic system [3,4,20,21,[73][74][75][76][77][78][79][80].…”

“…OMD symptoms include masticatory disturbances, biting of the tongue or cheek membrane, limited mouth opening, pain or discomfort of the muscles, dysphagia, dysarthria, esthetic problems, upper airway obstructions [19], and temporomandibular joint dislocations [49]. Most of these symptoms can impair daily activities, social embarrassment, cosmetic disfigurement, inability to work, and unemployment, forming a significant impact on the overall quality of life of the patient [3,4,[78][79][80]. Based on the site and direction of abnormal dystonic movements, OMD is classified into six subtypes: jaw closing, jaw opening, lingual, jaw deviation, jaw protrusion, and lip dystonia [3,4,78,80].…”

“…The mean age of OMD onset is in the 50s [76,79,80]. Notably, women are approximately twice as frequently affected as men, indicating female predominance (2:1) [76,79,80].…”

“…The mean age of OMD onset is in the 50s [76,79,80]. Notably, women are approximately twice as frequently affected as men, indicating female predominance (2:1) [76,79,80]. OMD can occur in isolation; however, it may present together as segmental or generalized dystonia.…”

“…For example, comorbid OMD and blepharospasm can form together as a segmental dystonia [85,86]. Common comorbidities of OMD include cervical dystonia, writer's cramp, and spasmodic dysphonia [3,78,79,84]. The ratio of isolated OMD among all OMD cases differs considerably as reported by neurologists (focal, 39%; segmental, 43%; generalized, 10%) [79] and an oral surgeon (focal, 90.8%; segmental, 10.4%; multifocal, 6.3%) [80].…”