Oromandibular dystonia – A systematic review

Dystonia: pathophysiology and the role of acupuncture in treatment

Dystonia is a complex neurological disorder characterized by involuntary muscle contractions, abnormal postures, and repetitive movements, which can lead to significant functional impairment and reduced quality of life. The disorder's pathophysiology involves a range of factors including genetic mutations, neurochemical imbalances, and structural abnormalities in the brain. Acupuncture has emerged as a promising complementary treatment for various types of dystonia, including post-stroke, cerebral palsy (CP)-related, limb, and cervical dystonia, as well as other hyperkinetic movement disorders. Clinical studies indicate that acupuncture may help to alleviate symptoms, decrease muscle spasticity, and improve overall patient outcomes. However, the effectiveness of acupuncture can vary depending on the specific type and severity of dystonia, with some studies reporting significant improvements, while others show more modest results. The variability in treatment response highlights the need for more robust research to better understand the mechanisms underlying acupuncture's effects and to develop standardized treatment protocols. The aim of this review is to provide a comprehensive overview of dystonia's pathophysiology and to assess the current evidence on the role of acupuncture in its treatment, identifying areas in which further research is needed to optimize therapeutic approaches.

Myoclonic status epilepticus with dystonia-like symptoms in patients with dementia: Report of two cases

We report cases of two elderly women with dementia who presented with a new-onset seizure disorder characterized by subtle, rhythmic muscular contractions involving the buccolingual region and the four limbs, persistent jaw opening, and abnormal cervical posture that mimicked myoclonus-dystonia syndrome and oromandibular dystonia. The symptoms lasted several minutes to a few hours. Video-polygraphic recordings revealed an electromyographic (EMG) pattern of brief, shock-like muscular contractions consistent with myoclonus that correlated with a high-amplitude (70-90 µV), 11-14 Hertz, bilaterally symmetric electroencephalographic (EEG) rhythm over the frontocentral regions. A time-locked relationship between the frontocentral EEG activity and the EMG myoclonic potentials demonstrated the cortical origin of myoclonus and therefore the epileptic nature of the disorder, whereas the oromandibular and cervical dystonic-like postures suggested the pathogenic involvement of subcortical structures. The intravenous administration of diazepam suppressed the clinical symptoms and the EEG-EMG correlate of myoclonus. The clinical and neurophysiological findings illustrate a form of myoclonic status epilepticus (SE) with dystonia-like symptoms resulting from the functional involvement of cortical and subcortical structures. The manifestation of subtle, rhythmic myoclonus and dystonic-like postures in patients with atypical EEG patterns of SE may require challenging differential diagnoses with myoclonus-dystonia syndrome and oromandibular dystonia.

Aripiprazole-Induced Orofacial Dyskinesia in a Young Male: A Case Report

We report the case of a 23-year-old man who developed orofacial dyskinesia secondary to aripiprazole whilst being treated for psychosis in the hospital. He was known to mental health services and had suffered a relapse of bipolar affective disorder. Upon cessation of aripiprazole and commencement of quetiapine, there was a rapid reversal of his movement disorder. He also did not have any notable risk factors associated with developing orofacial dyskinesia beyond having an affective disorder, which highlights the unusual and rare occurrence of this side effect with the use of aripiprazole. Unlike many first-generation antipsychotics, aripiprazole had been previously reported to be protective against and also treat extrapyramidal side effects (EPSE) due to its mixed mechanism of action, which includes being a partial dopamine receptor 2 (DR2) agonist.

Oromandibular dystonia: from onset to spread a multicenter italian study

BACKGROUND

Detailed information about the epidemiological and phenomenological differences among the aetiological subtypes of oromandibular dystonia (OMD) is lacking. Moreover, the OMD tendency to spread to other body sites has never been investigated.

AIM

To compare the main demographic and clinical features of OMD in different aetiological groups and assess the risk of spread.

MATERIALS AND METHODS

We retrospectively analysed data from patients contained in the Italian Dystonia Registry. The risk of spread was assessed by Kaplan Meyer curves and Cox regression analysis.

RESULTS

The study included 273 patients (175 women) aged 55.7 years (SD 12.7) at OMD onset. Female predominance was observed. Idiopathic dystonia was diagnosed in 241 patients, acquired dystonia in 22. In 50/273 patients, dystonia started in the oromandibular region (focal OMD onset); in 96/273 patients the onset involved the oromandibular region and a neighbouring body site (segmental/multifocal OMD onset); and in 127/273 patients OMD was a site of spread from another body region. Sensory trick (ST) and positive family history predominated in the idiopathic group. No dystonia spread was detected in the acquired group, whereas spread mostly occurred within the first five years of history in 34% of the focal OMD onset idiopathic patients. Cox regression analysis revealed ST as a significant predictor of spread (HR, 12.1; 95% CI, 2.5 - 18.8; P = 0.002).

CONCLUSION

This large study provides novel information about the clinical phenomenology of idiopathic and acquired OMD. We pointed out a possible role of oestrogens in favouring dystonia development. Moreover, we described for the first time the association between ST and dystonia spread, revealing possible common pathophysiological mechanisms. Our findings may be suggested as a referral point for future pathophysiological and therapeutic studies on OMD.

Oromandibular Dystonia as a Side Effect of Methotrexate

Oromandibular dystonia is a focal dystonia characterized by involuntary movements of the jaw, oropharynx, lips, and tongue. The diagnosis of oromandibular dystonia is clinical and can be complex. For effective treatment, it is essential to understand its underlying etiology. A 70-year-old man was referred to our center with a diagnosis of Meige's syndrome, which had been present for five and a half years, for receiving botulinum toxin-A (BoNT-A) injections. Upon physical examination, he exhibited oromandibular dystonia, with a score of 177 points on the Oromandibular Dystonia Rating Scale (OMDRS). He had a history of taking methotrexate for six years, as he was diagnosed with psoriatic arthritis during that time. The possibility of methotrexate-induced dystonia was considered. A switch from methotrexate to sulfasalazine was initiated. Subsequently, the patient showed progressive improvement in his symptoms, as reflected by an OMDRS score of 103 points. After eight weeks, the medical team decided to supplement the treatment with BoNT-A injections, resulting in an OMDRS score of 75. While there is currently no definitive evidence linking the use of methotrexate to the development of dystonia, it is advisable to consider oromandibular dystonia as a potential side effect of methotrexate until more robust evidence becomes available.

Botulinum toxin for motor disorders

Botulinum neurotoxins are a group of biological toxins produced by the gram-negative bacteria Clostridium botulinum. After intramuscular injection, they produce dose-related muscle relaxation, which has proven useful in the treatment of a large number of motor and movement disorders. In this chapter, we discuss the utility of botulinum toxin treatment in three major and common medical conditions related to the dysfunction of the motor system, namely dystonia, tremor, and spasticity. A summary of the existing literature is provided along with different techniques of injection including those recommended by the authors.

Effects of Botulinum Toxin Therapy on Health-Related Quality of Life Evaluated by the Oromandibular Dystonia Rating Scale

Oromandibular dystonia (OMD) refers to a focal dystonia in the stomatognathic system. Health-related quality of life (HRQoL) in isolated dystonia is associated with non-motor symptoms such as depression, anxiety, and pain, as well as motor symptoms. To evaluate HRQoL in patients with OMD, the therapeutic effects of botulinum neurotoxin (BoNT) therapy were assessed using a recently developed and validated comprehensive measurement tool called the Oromandibular Dystonia Rating Scale (OMDRS). Altogether, 408 patients (jaw closing dystonia, n = 223; tongue (lingual) dystonia, n = 86; jaw opening dystonia, n = 50; jaw deviation dystonia, n = 23; jaw protrusion dystonia, n = 13; and lip (labial) dystonia, n = 13) were evaluated at baseline and after the end of BoNT therapy or in a stable status. The total OMDRS score reduced significantly from 149.1 to 57.6 (p < 0.001). Mean improvement was 63.1%. All examiner-rated subscales (severity, disability, and pain) and patient-rated questionnaire scores (general, eating, speech, cosmetic, social/family life, sleep, annoyance, mood, and psychosocial function) were significantly lower at the endpoint than at baseline (p < 0.001). The BoNT injection had a highly positive impact on patient HRQoL, and the OMDRS could evaluate both motor phenomena and non-motor symptoms.

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

Various movement disorders, such as oromandibular dystonia, oral dyskinesia, bruxism, functional (psychogenic) movement disorder, and tremors, exist in the stomatognathic system. Most patients experiencing involuntary movements due to these disorders visit dentists or oral surgeons, who may be the first healthcare providers. However, differential diagnoses require neurological and dental knowledge. This study aimed to review scientific advances in botulinum toxin therapy for these conditions. The results indicated that botulinum toxin injection is effective and safe, with few side effects in most cases when properly administered by an experienced clinician. The diagnosis and treatment of movement disorders in the stomatognathic system require both neurological and dental or oral surgical knowledge and skills, and well-designed multicenter trials with a multidisciplinary team approach must be necessary to ensure accurate diagnosis and proper treatment.

Patient selection and injection techniques for botulinum neurotoxin in oromandibular dystonia

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Botulinum toxin is considered as the first-line therapy in oromandibular dystonia (OMD) by most experts and evidence-based literature.

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Oromandibular dystonia (OMD) can be classified into several subtypes so primary muscle involvements can be identified for botulinum toxin (BoNT) injections.

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This review article aims to provide a framework for practical clinical approaches in patients with OMD for BoNT injections.

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Careful stepwise planning is recommended to identify primary muscles responsible and employ a conservative approach to dosing titration.

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Treating physicians should be diligent to observe for adverse events as muscles involved in OMD are small, delicate and situated in close proximity.

Oromandibular dystonia (OMD) is a form of focal dystonia that involves the masticatory, lower facial, labial, and lingual musculature. It is a disabling disorder which had limited treatment options until the recent introduction of botulinum toxin (BoNT) as the recommended first-line therapy by most experts and evidence-based literature. Owing to the complex relationship between the muscles of mastication and surrounding muscles, there is a wide variety of dynamic clinical presentations, making clinical recognition and the corresponding approach to BoNT injection therapy difficult. In this review, the authors provide a framework for practical clinical approaches, beginning with the recognition of clinical subtypes of OMD (jaw-opening, jaw-closing, jaw-deviating, lingual, peri-oral, and/or pharyngeal dystonias), followed by patient selection and clinical evaluation to determine function interferences, with injection techniques illustrated for each subtype. Careful stepwise planning is recommended to identify the muscles that are primarily responsible and employ a conservative approach to dosing titration. Treating physicians should be diligent in checking for adverse events, especially for the first few injection cycles, as muscles involved in OMD are small, delicate, and situated in close proximity. It is recommended that future studies should aim to establish the clinical efficacy of each subtype, incorporating muscle targeting techniques and patient-centred outcome measures that are related to disturbed daily functions.