Os odontoideum and craniovertebral junction instability secondary to dystonia: case series and review of the literature

INTRODUCTION

Os odontoideum refers to a rounded ossicle detached from a hypoplastic odontoid process at the body of the axis. The aetiology has been debated and believed to be either congenital or acquired (resulting from trauma). Os odontoideum results in incompetence of the transverse ligament and thus predisposes to atlantoaxial instability and spinal cord injury.

METHODS/RESULTS

Three cases of children with severe dystonic cerebral palsy presenting with myelopathic deterioration secondary to atlantoaxial instability due to os odontoideum are presented. This observation supports the hypothesis of os odontoideum being an acquired phenomenon, secondary to chronic excessive movement with damage to the developing odontoid process.

CONCLUSION

In children with cerebral palsy and dystonia, pre-existing motor deficits may conceal an evolving myelopathy and result in delayed diagnosis of clinically significant atlantoaxial subluxation.

Multiple motor disorders in cerebral palsy

AIM

To characterize motor disorders in children and young people with cerebral palsy (CP).

METHOD

This was a cross-sectional study of 582 children and young people with CP (mean age 9 years 7 months; range 11 months-19 years 9 months; standard deviation 4 years 11 months; 340 males) attending a rehabilitation clinic at a specialized children's hospital (May 2018-March 2020). Data on motor disorders, topography, functional classifications, and non-motor features, such as epilepsy, intellectual disability, and sensory impairments, were collected using the Australian Cerebral Palsy Register CP Description Form.

RESULTS

Fifty-five per cent (n = 321) of children and young people with CP presented with multiple motor disorders, often affecting the same limb(s). The most common motor disorders were spasticity and dystonia (50%), spasticity only (36%), and dystonia only (6%), but 18 different combinations were identified, including choreoathetosis, ataxia, and generalized hypotonia with increased reflexes. Children with spasticity only had less severe functional deficits (p < 0.001) and lower rates of associated intellectual disability (p < 0.01) and epilepsy (p < 0.001) than those with both spasticity and dystonia.

INTERPRETATION

Multiple motor disorders in children and young people with CP are common and associated with more severe functional impairment. Accurate assessment of motor disorders is essential to guide prognosis and ensure personalized evidence-based interventions.

WHAT THIS PAPER ADDS

More than half of children and young people with cerebral palsy presented with multiple motor disorders. Dystonia was identified in 60% of study participants. Dystonia was associated with more severe functional impairments and rates of non-motor features.

Essential Tremor and Essential Tremor Plus Are Essentially Similar Electrophysiologically

BACKGROUND

The merits of classifying the heterogeneous group of essential tremors into essential tremor (ET) and essential tremor plus (ETP) are debated.

OBJECTIVES

We studied the electrophysiological and spiral characteristics of tremor in ET and ETP.

METHODS

We reviewed standardized videos from a tremor database and clinically classified patients into ET, ETP, or dystonic tremor (DT). The following variables were derived from combined tri-axial accelerometry-surface electromyography (EMG)-peak frequency, total power, peak power, full width half maximum, tremor stability index and EMG-coherence. We analyzed hand-drawn spirals to derive mean deviation, tremor variability, inter-, and intra-loop widths. We compared these variables among the groups.

RESULTS

We recruited 72 participants (81.9% male) with mean age 47.7 ± 16.1 years and Fahn-Tolosa-Marin Tremor Rating Scale total score 31.1 ± 14.1. Patients with ET were younger (P = 0.014) and had less severe tremor (P = 0.020) compared to ETP and DT. In ETP group, 48.6% had subtle dystonia. Peak frequency was greater in ETP (7.3 ± 0.3 Hz) compared to DT (6.1 ± 0.4 Hz; P = 0.024). Peak power was greater in ETP and DT for postural tremor. Rest tremor was recordable on accelerometry in 26.7% of ET. Other variables were similar among the groups.

CONCLUSION

Electrophysiological evaluation revealed postural tremor of frequency 6 to 7 Hz in ET, ETP, and DT with subtle differences more severe tremor in ETP and DT, and higher frequency in ETP compared to DT. Our findings suggest a similar tremor oscillator in these conditions, supporting the view that these entities are part of a spectrum of tremor disorders, rather than distinct etiological entities.

Focal task-specific hand dystonia related to esports in a rhythm gamer: A case report

Herein, we report a novel case of focal task-specific dystonia of the upper extremity that occurred in a 27-year-old man who presented with flexion of the left third, fourth, and fifth fingers exclusively during rhythm gameplay. Dystonia during electronic sports should be recognized as a new type of occupational dystonia.

Predictive and diagnostic measures for kernicterus spectrum disorder: a prospective cohort study

BACKGROUND

Kernicterus spectrum disorder (KSD) resulting from neonatal hyperbilirubinemia remains a common cause of cerebral palsy worldwide. This 12-month prospective cohort study followed neonates with hyperbilirubinemia to determine which clinical measures best predict KSD.

METHODS

The study enrolled neonates ≥35 weeks gestation with total serum bilirubin (TSB) ≥ 20 mg/dl admitted to Aminu Kano Hospital, Nigeria. Clinical measures included brain MRI, TSB, modified bilirubin-induced neurologic dysfunction (BIND-M), Barry-Albright Dystonia scale (BAD), auditory brainstem response (ABR), and the modified KSD toolkit. MRI signal alteration of the globus pallidus was scored using the Hyperbilirubinemia Imaging Rating Tool (HIRT).

RESULTS

Of 25 neonates enrolled, 13/25 completed 12-month follow-up and six developed KSD. Neonatal BIND-M ≥ 3 was 100% sensitive and 83% specific for KSD. Neonatal ABR was 83% specific and sensitive for KSD. Neonatal HIRT score of 2 was 67% sensitive and 75% specific for KSD; this increased to 100% specificity and sensitivity at 12 months. BAD ≥ 2 was 100% specific for KSD at 3-12 months, with 50-100% sensitivity.

CONCLUSIONS

Neonatal MRIs do not reliably predict KSD. BIND-M is an excellent screening tool for KSD, while the BAD or HIRT score at 3 or 12 months can confirm KSD, allowing for early diagnosis and intervention.

IMPACT

The first prospective study of children with acute bilirubin encephalopathy evaluating brain MRI findings over the first year of life. Neonatal MRI is not a reliable predictor of kernicterus spectrum disorders (KSD). Brain MRI at 3 or 12 months can confirm KSD. The modified BIND scale obtained at admission for neonatal hyperbilirubinemia is a valuable screening tool to assess risk for developing KSD. The Barry Albright Dystonia scale and brain MRI can be used to establish a diagnosis of KSD in at-risk infants as early as 3 months.

Treatment of oromandibular dystonia with botulinum toxin A improves apnea in a teenager with quadriplegic cerebral palsy: A case report

This report describes a 15-year-old female with known spastic and dystonic quadriplegic cerebral palsy (CP), Gross Motor Function Classification System IV, and obstructive sleep apnea (OSA). She experienced decreased apneic episodes after receiving onabotulinumtoxin A (BoNT-A) injections for the treatment of oromandibular dystonia (OMD). After her OSA diagnosis, she initially received injections to the bilateral masseter and temporalis muscles with no effect on the frequency of nightly apneic episodes. Subsequently, the bilateral lateral pterygoid muscles were added and she was later noted to have fewer apneic episodes overnight. This case report describes the use of BoNT-A in the muscles of mastication for management of OMD and the ensuing improvement in OSA in a teenager with CP.

Femur Fractures in 5 Individuals With Pantothenate Kinase-associated Neurodegeneration: The Role of Dystonia and Suggested Management

BACKGROUND

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare, neurodegenerative disorder that manifests with progressive loss of ambulation and refractory dystonia, especially in the early-onset classic form. This leads to osteopenia and stress on long bones, which pose an increased risk of atraumatic femur fractures. The purpose of this study is to describe the unique challenges in managing femur fractures in PKAN and the effect of disease manifestations on surgical outcomes.

METHODS

A retrospective case review was conducted on 5 patients (ages 10 to 20 y) with PKAN with a femur fracture requiring surgical intervention. Data regarding initial presentation, surgical treatment, complications, and outcomes were obtained.

RESULTS

All patients were non-ambulatory, with 4 of 5 patients sustaining an atraumatic femur fracture in the setting of dystonia episode. One patient had an additional contralateral acetabular fracture. Postoperatively, 4 of the 5 patients sustained orthopaedic complications requiring surgical revision, with 3 of these secondary to dystonia. Overall, 4 required prolonged hospitalization in the setting of refractory dystonia.

CONCLUSION

Femur fractures in PKAN present distinct challenges for successful outcomes. A rigid intramedullary rod with proximal and distal interlocking screws is most protective against surgical complications associated with refractory dystonia occurring during the postoperative period. Multidisciplinary planning for postoperative care is essential and may include aggressive sedation and pain management to decrease the risk of subsequent injuries or complications.

LEVEL OF EVIDENCE

Level IV.

The Spectrum of Non-Parkinsonian Tremor: A Registry at a Tertiary Care Teaching Institute

Background

Tremors other than those associated with Parkinson's disease (non-parkinsonian tremor) are commonly observed in clinical settings. However, their frequency and clinical characteristics have rarely been reported.

Objectives

To classify non-parkinsonian tremors based on the consensus statement on the classification of tremors, from the task force of the International Parkinson and Movement Disorder Society published in 2018.

Methods

A prospective registry at a tertiary care teaching institute.

Results

A total of 475 patients with non-parkinsonian tremors were recruited for the study. 67.57% (n = 321) of our patients were male and a family history of tremor was present in 20.84% (n = 99) of patients. Dystonic tremor (DT) was the most common non-parkinsonian tremor (33.26%). 27.78% of patients fulfilled the new classification criteria for essential tremor, with 13.47% classified as pure ET (ET) and 14.31% exhibiting neurological soft signs, leading to the classification of ET plus (ETP). Patients with ETP had more family history (57.35%) [vs DT (26.48%, p = 0.00004) and ET (10.93%, p = 0.00003], longer duration of disease [mean ± standard deviation (SD) = 9.53 ± 8.64 years] [vs DT (5.60 ± 5.93, p = 0.0003) and ET (6.38 ± 5.97, p = 0.01) years], and more severe tremor as measured by the essential tremor rating assessment scale total score [mean ± SD = 27.42 ± 11.70] [vs DT (23.50 ± 8.62, p = 0.007) and ET (22.12 ± 8.19, p = 0.007)] compared with patients with DT and ET.

Conclusions

DT was the most common cause of non-parkinsonian tremor in our registry followed by essential tremor syndrome. ETP was more common than ET.

ATP1A3 related disease manifesting as rapid onset dystonia-parkinsonism with prominent myoclonus and exaggerated startle

We report ATP1A3-associated rapid-onset dystonia-parkinsonism with an atypical presentation including myoclonus and exaggerated startle in four patients. Their prominence over parkinsonism prompted consideration of a syndromic diagnosis of myoclonus dystonia. ATP1α3 dysfunction in GABAergic neurons could explain these examination findings. The spectrum of ATP1A3-associated movement disorders includes myoclonus-dystonia.

Deep Brain Stimulation for an Unusual Presentation of Myoclonus Dystonia Associated with Russell-Silver Syndrome

Background

Myoclonus dystonia syndrome typically results from autosomal dominant mutations in the epsilon-sarcoglycan gene (SGCE) via the paternally expressed allele on chromosome 7q21. There is evidence that deep brain stimulation (DBS) is beneficial for this genotype, however, there are few prior case reports on DBS for myoclonus dystonia syndrome secondary to other confirmed genetic etiologies.

Case Report

A 20-year-old female with concomitant Russell-Silver syndrome and myoclonus dystonia syndrome secondary to maternal uniparental disomy of chromosome 7 (mUPD7) presented for medically refractory symptoms. She underwent DBS surgery targeting the bilateral globus pallidus interna with positive effects that persisted 16 months post-procedure.

Discussion

We present a patient with the mUPD7 genotype for myoclonus dystonia syndrome who exhibited a similar, if not superior, response to DBS when compared to patients with other genotypes.

Highlights

This report outlines the first described case of successful deep brain stimulation treatment for a rare genetic variant of myoclonus dystonia syndrome caused by uniparental disomy at chromosome 7. These findings may expand treatment options for patients with similar conditions.

Spasticity and movement disorders in cerebral palsy

PURPOSE

To review the neurosurgical treatments of children with movement disorders associated with cerebral palsy (CP) during the previous decades, up to the present day.

METHODS

An extensive literature review was undertaken to identify important publications about this subject. My experience treating children with these disorders over the past three decades was included in the individual sections.

RESULTS

Peripheral neurotomies have been developed for children with focal spasticity. For those with spastic paraparesis, selective lumbar rhizotomies were developed, and for those with spastic quadriparesis, intrathecal baclofen infusions were developed. Both effectively alleviate spasticity in the affected extremities. Generalized dystonia associated with CP has been treated with deep brain stimulation with mild improvement, but treatment with intrathecal baclofen and intraventricular baclofen improve those movements markedly. No effective treatment has been reported for children with athetoid CP. For those with choreiform CP, deep brain stimulation may be effective but intrathecal baclofen does not appear to be.

CONCLUSION

Treatment of children with movement disorders associated with CP increased slowly in the 1970s and 1980s but accelerated rapidly in the 1990s with the introduction of lumbar dorsal rhizotomies and intrathecal baclofen. In the last 30 years, tens of thousands of children with spasticity and movement disorders associated with CP have been treated by pediatric neurosurgeons, and their care has become an integral component of current pediatric neurosurgical practice.

Spastic dystonia: Still a valid term

Hypertonia in childhood may arise because of a variable combination of neuronal and non-neuronal factors. Involuntary muscle contraction may be due to spasticity or dystonia, which represent disorders of the spinal reflex arch and of central motor output respectively. Whilst consensus definitions for dystonia have been established, definitions of spasticity vary, highlighting the lack of a single unifying nomenclature in the field of clinical movement science. The term spastic dystonia refers to involuntary tonic muscle contraction in the context of an upper motor neuron (UMN) lesion. This review considers the utility of the term spastic dystonia, exploring our understanding of the pathophysiology of dystonia and the UMN syndrome. An argument is advanced that spastic dystonia is a valid construct that warrants further exploration. WHAT THIS PAPER ADDS: There is no single universally accepted definitions for terms commonly used to describe motor disorders. Spasticity and dystonia are phenomenologically and pathophysiologically distinct entities. Spastic dystonia represents a subset of dystonia, but with pathophysiological mechanisms more in common with spasticity.

TMEM151A variants associated with paroxysmal kinesigenic dyskinesia

TMEM151A, located at 11q13.2 and encoding transmembrane protein 151A, was recently reported as causative for autosomal dominant paroxysmal kinesigenic dyskinesia (PKD). Here, through comprehensive analysis of sporadic and familial cases, we expand the clinical and mutation spectrum of PKD. In doing so, we clarify the clinical and genetic features of Chinese PKD patients harboring TMEM151A variants and further explore the relationship between TMEM151A mutations and PKD. Whole exome sequencing was performed on 26 sporadic PKD patients and nine familial PKD pedigrees without PRRT2 variants. Quantitative real-time PCR was used to assess the gene expression of frameshift mutant TMEM151A in a PKD patient. TMEM151A variants reported to date were reviewed. Four TMEM151A variants were detected in four unrelated families with 12 individuals, including a frameshift mutation [c.606_607insA (p.Val203fs)], two missense mutations [c.166G > A (p.Gly56Arg) and c.791T > C (p.Val264Ala)], and a non-pathogenic variant [c.994G > A (p.Gly332Arg)]. The monoallelic frameshift mutation [c.606_607insA (p.Val203fs)] may cause TMEM151A mRNA decay, suggesting a potential pathogenic mechanism of haploinsufficiency. Patients with TMEM151A variants had short-duration attacks and presented with dystonia. Our study provides a detailed clinical description of PKD patients with TMEM151A mutations and reports a new disease-causing mutation, expanding the known phenotypes caused by TMEM151A mutations and providing further detail about the pathoetiology of PKD.

Debunking the Puzzle of Eyelid Apraxia: The Muscle of Riolan Hypothesis

PURPOSE

Apraxia of eyelid opening (AEO) has been defined by the presence of an intermittent nonparalytic bilateral loss of the volitional ability to open the eyes or to maintain the eyelids in a sustained elevated position. It is not known whether the condition represents an apraxia, a dystonia, or a freezing phenomenon, and several different nomenclatorial terms have been suggested for this condition including the so-called AEO (scAEO), blepahrocolysis, focal eyelid dystonia, and so on. The primary goal of this review is to attempt to clarify the pathogenetic mechanisms underlying scAEO as a clinical phenomenon. This review also addresses the issue of whether scAEO is part of the spectrum of blepharospasm (BSP) which includes BSP, dystonic blinks and other dystonic eyelid conditions, or whether it is a separate phenomenologically heterogeneous disease with clinical features that merely overlap with BSP.

METHODS

A literature review was conducted in PubMed, MEDLINE, PubMed Central (PMC), NCBI Bookshelf, and Embase for several related keywords including the terms "apraxia of eyelid opening," "pretarsal blepharospasm," "blepharocolysis," "eyelid freezing," "eyelid akinesia," "levator inhibition," "blepharospasm-plus," as well as "blepharospasm." The clinical findings in patients with scAEO who fulfilled the classic diagnostic criteria of the disease that were originally set by Lepore and Duvoisin were included, while patients with isolated blepharospasm or dystonic blinks (DB) were excluded. In addition, electromyographic (EMG) studies in patients with scAEO were reviewed in detail with special emphasis on studies that performed synchronous EMG recordings both from the levator muscle (LPS) and the pretarsal orbicularis oculi muscle (OO).

RESULTS

The apraxia designation is clearly a misnomer. Although scAEO behaves clinically as a hypotonic freezing phenomenon, it also shares several cardinal features with focal dystonias. The authors broadly categorized the EMG data into 3 different patterns. The first pattern (n = 26/94 [27.6%]) was predominantly associated with involuntary discharges in the OO muscle and has been termed pretarsal blepharospasm (ptBSP). The commonest pattern was pattern no. 2 (n = 53/94 [56.38%]), which was characterized by involuntary discharges in the OO muscle, together with a disturbed reciprocal innervation of the antagonist levator muscle and is dubbed disturbed reciprocal innervation (DRI). This EMG pattern is difficult to discern from the first pattern. Pattern no. 3 (n = 15/94 [15.9%]) is characterized by an isolated levator palpebrae inhibition (ILPI). This levator silence was observed alone without EMG evidence of contractions in the pretarsal orbicularis or a disturbed reciprocal relation of both muscles.

CONCLUSION

EMG evidence shows that the great majority (84%) of patients show a dystonic pattern, whereas ILPI (16%) does not fit the dystonic spectrum. The authors propose that a spasmodic contraction of the muscle of Riolan may be the etiological basis for levator inhibition in patients with ILPI. If this is true, all the 3 EMG patterns observed in scAEO patients (ptBSP, DRI, and ILPI) would represent an atypical form of BSP. The authors suggest coining the terms Riolan muscle BSP ( rmBSP ) for ILPI, and the term atypical focal eyelid dystonia ( AFED ) instead of the term scAEO, as both terms holistically encompass both the clinical and EMG data and concur with the authors' theorem.

[Methods and results of neurosurgical treatment of cerebral palsy]

Treatment of spastic syndrome and muscular dystonia in patients with cerebral palsy is a complex clinical problem. Effectiveness of conservative treatment is not high enough. Modern neurosurgical techniques for spastic syndrome and dystonia are divided into destructive interventions and surgical neuromodulation. Their effectiveness is different and depends on the form of disease, severity of motor disorders and age of patients.

OBJECTIVE

To evaluate the effectiveness of various methods of neurosurgical treatment of spasticity and muscular dystonia in patients with cerebral palsy.

MATERIAL AND METHODS

We To evaluate the effectiveness of various methods of neurosurgical treatment of spasticity and muscular dystonia in patients with cerebral palsy.analyzed literature data in the PubMed database using the keywords «cerebral palsy», «spasticity», «dystonia», «selective dorsal rhizotomy», «selective neurotomy», «intrathecal baclofen therapy», «spinal cord stimulation», «deep brain stimulation».

RESULTS

Effectiveness of neurosurgery was higher for spastic forms of cerebral palsy compared to secondary muscular dystonia. Destructive procedures were the most effective among neurosurgical operations for spastic forms. Effectiveness of chronic intrathecal baclofen therapy decreases in follow-up due to secondary drug resistance. Destructive stereotaxic interventions and deep brain stimulation are used for secondary muscular dystonia. Effectiveness of these procedures is low.

CONCLUSION

Neurosurgical methods can partially reduce severity of motor disorders and expand the possibilities of rehabilitation in patients with cerebral palsy.

Pearls & Oy-sters: Gait Instability, Jaw Dystonia, and Horizontal Diplopia in a Woman With Anti-Ri Antibodies and Breast Cancer

A 40-year-old woman was admitted for 6 months of progressive gait disturbance, lower limb-predominant weakness, stiffness, falls, jaw dystonia, horizontal diplopia, and weight loss. Neurologic examination revealed horizontal gaze paresis, limited jaw opening with palpable masseter hypertrophy, and spastic paraparesis with sustained clonus and upgoing plantar responses. MRI revealed T2-hyperintense signal abnormalities in the dorsal pons, medulla, and upper cervical cord central gray matter extending to C3, without gadolinium enhancement. CSF showed mildly elevated protein and immunoglobulin (IgG) index with CSF-specific oligoclonal bands. Neural autoantibody testing was positive for anti-Ri in CSF and serum by mouse brain indirect immunofluorescence and immunoblot. Testing for aquaporin-4 (AQP4)-IgG and myelin oligodendrocyte glycoprotein (MOG)-IgG by cell-based assay was negative. The patient received methylprednisolone 1 g for 5 days and IV immunoglobulin 2 g/kg over 2 days with prednisone taper and botulinum toxin injections for jaw dystonia. PET-CT revealed an enlarged left axillary lymph node with high FDG uptake. Left axillary lymph node biopsy confirmed high-grade, locally invasive breast adenocarcinoma. Neurologic stabilization was documented at 2-week follow-up after hospital discharge before modified radical mastectomy. Our case demonstrates a clinical triad highly suggestive of anti-Ri-associated paraneoplastic neurologic syndrome (Ri-PNS): gait instability, jaw dystonia, and horizontal gaze paresis. The more slowly progressive course and poor response to immunotherapy help distinguish it from AQP4-IgG-seropositive neuromyelitis optica spectrum disorder (NMOSD) and MOG-IgG-associated disease (MOGAD) that share similar radiographic features. Early diagnosis, prompt immunotherapy, and cancer treatment are paramount for disease stabilization.

[Parkinson's Disease with Intolerable Painful Dystonia: Classification and Therapeutic Choices of Pain in Parkinson' Disease]

Disabling painful dystonia is one of the most burdensome symptoms that a patient with Parkinson's disease (PD) experiences. How do we treat disabling painful dystonia in PD? In this review, classification and mechanisms of pain and their management in PD especially for dystonia-related pain are described. Moreover, painful bilateral dystonic foot spasm is also an important development to be considered in the early stage of the disease. Recent classification of pain in PD does not involve this symptom, partly because this symptom is relatively unobserved due to early initiation of treatment in PD patients. Treatment options for dystonia-related pain are diverse and are necessarily contingent on the cause of dystonia in PD. Reducing L-dopa and other drugs is useful for patients with on-dystonia and dyskinesia-related pain in PD. Increasing L-dopa and other drugs are better for early morning dystonia and off-period dystonia-related pain in PD. Finally, as severe and troublesome painful dystonia is often challenging to treat, continuous dopaminergic stimulation such as treatment with levodopa-carbidopa intestinal gel is considered effective for these symptoms.

Clinical features, pathophysiology, treatment, and controversies of tremor in dystonia

Dystonia and tremor frequently co-occur. In some cases, they have shared biological mechanisms, while in others dystonia and tremor are two comorbid conditions. The term "dystonic tremor" is used to describe tremor in those who have dystonia. Two mutually exclusive definitions of "dystonic tremor" were proposed. According to one definition, dystonic tremor is the tremor in the dystonic body part. An alternate definition of dystonic tremor entails irregular and jerky oscillations that have saw tooth appearance with or without overt dystonia. This paper outlines the differences in two definitions of dystonic tremor and identifies their limitations. Given the diverse views defining "dystonic tremor", this paper will use the term "tremor in dystonia". In addition, we will outline different ways to separate the subtypes of tremor in dystonia. Then we will discuss pathophysiological mechanisms derived from the objective measures and single neuron physiology analyses of tremor in dystonia. This article is part of the Special Issue "Tremor" edited by Daniel D. Truong, Mark Hallett, and Aasef Shaikh.

The Impact of Anxiety and Upper Limb Disability on Participation Levels in People With Dystonia: An Observational Cross-Sectional Case-Control Study

OBJECTIVE

This study sought to evaluate the level of anxiety in people with dystonia and to examine a possible relationship between the level of participation, anxiety, and functional limitations.

DESIGN

This is an observational, cross-sectional, case-control study with 12 cases of focal dystonia and 12 healthy controls aged between 18 and 75 yrs. The Hamilton Anxiety Rating Scale, the QuickDASH scale, and the Measure of Participation and Activities were used. Differences in scores and effect size were analyzed through the Student t test and Cohen d test. A multiple regression model was performed to determine the relationship between variables.

RESULTS

People with dystonia obtained higher scores in the three subsections of the Hamilton Anxiety Rating Scale (total anxiety, psychiatric anxiety, and somatic anxiety; P < 0.05) and on the QuickDASH scale, together with lower scores in participation in activities of daily living of the Measure of Participation and Activities (P = 0.01). Greater upper limb disability was associated with a greater negative impact on participation in activities of daily living (P < 0.01); however, no significant relationship was found with anxiety (P > 0.05).

CONCLUSIONS

This study suggests that the ability of people with dystonia to participate in society is negatively affected by the level of disability of the upper limb, but even when anxiety-age-related differences were controlled for, no relationship was found between variables.

Bilateral thalamic changes in anti-NMDAR encephalitis presenting with hemichorea and dystonia and acute transient psychotic disorder

Anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis is one of the most common causes of autoimmune encephalitis. Both movement disorders and neuropsychiatric manifestations are considered core features of anti-NMDAR encephalitis. Strong clinical suspicion, along with NMDAR antibody positivity in paired sample of serum and cerebrospinal fluid, with supportive MRI changes clinch diagnosis in majority. We herein report a case of a middle-aged woman with subacute behavioral abnormalities, which were so severe that forced her to attempt suicide. Hemichorea and dystonia, which appeared later in course, are not previously reported movement disorders in combination in anti-NMDAR encephalitis. Further, magnetic resonance imaging showed bilateral thalamic hyperintensities with diffusion restriction, which are in turn not described in this entity. After amalgamation of history, especially the presence of neuropsychiatric symptoms, clinical features, physical examination, and investigations, the diagnosis of anti-NMDAR encephalitis could be established. Our case not only highlights that the combination of hemichorea and dystonia can be features of anti-NMDAR encephalitis, but adds novelty by bilateral symmetric thalamic changes.

Bilateral polymicrogyria associated with dystonia: A new neurogenetic syndrome?

The clinical presentation of bilateral perisylvian polymicrogyria (PMG) is highly variable, including oromotor dysfunction, epilepsy, intellectual disability, and pyramidal signs. Extrapyramidal features are extremely rare. We present four apparently unrelated patients with a unique association of PMG with dystonia. The clinical, genetic, and radiologic features are described and possible mechanisms of dystonia are discussed. All patients were female and two were born to consanguineous families. All presented with early childhood onset dystonia. Other neurologic symptoms and signs classically seen in bilateral perisylvian PMG were observed, including oromotor dysfunction and speech abnormalities ranging from dysarthria to anarthria (4/4), pyramidal signs (3/4), hypotonia (3/4), postnatal microcephaly (1/4), and seizures (1/4). Neuroimaging showed a unique pattern of bilateral PMG with an infolded cortex originating primarily from the perisylvian region in three out of four patients. Whole exome sequencing was performed in two out of four patients and did not reveal pathogenic variants in known genes for cortical malformations or movement disorders. The dystonia seen in our patients is not described in bilateral PMG and suggests an underlying mechanism of impaired connectivity within the motor network or compromised cortical inhibition. The association of bilateral PMG with dystonia in our patients may represent a new neurogenetic disorder.

The Consequences of Oromandibular Dystonia on Communicative Participation: A Qualitative Study of the Insider's Experiences

Purpose The purpose of this study was to obtain a self-reported account of the experience of living with oromandibular dystonia (OMD) to gain a better understanding of both the daily facilitators and barriers to communicative participation and the strategies used for adapting to life with OMD. Method Eight individuals with OMD and dysarthria participated in 1 face-to-face, semistructured interview. Interviews were audio-recorded and transcribed verbatim. Qualitative, phenomenological methods of coding, immersion, and emergence were used in the analysis of interview data. Results Three major themes and 7 subthemes emerged from the analysis of interview data. First, "speaking is different now" provided examples of how speech changes are manifested in various life situations. Second, "my roles have changed" addressed how OMD has impacted work, home, and social roles. Third, "I accept it and move on" involved finding strategies that help and adopting a different perspective. Conclusion We suggest that the management of OMD must take a more holistic approach by addressing consequences beyond the physical symptoms and be tailored to each individual based on his or her personal concerns and goals.

Dystonia

This chapter presents a review of the literature for falls and abnormalities of balance and gait in isolated dystonia syndromes. Balance appears to be relatively preserved in primary and focal dystonias, except when postural abnormalities significantly displace the center of gravity of the body. Gait can be affected by abnormal dystonic movements and limb deformities, and is commonly abnormal in generalized dystonia. Impairment of gait can also be seen in patients with cervical dystonia when it results in abnormal posturing, and severe cases of blepharospasm leading to functional blindness. Gait abnormalities have also been described in dystonia associated with dopa-responsive dystonia (DRD) and Wilson disease. The data on dystonia and falls are scarce but it has been described as one of the main symptoms of DRD. Local field potential recordings point to abnormal synchronization activity in the pallidum as the main pathophysiologic finding. Cerebellar dysfunction has been reported in patients with primary dystonia and some forms of focal dystonia. While contradictory data have been published on the association between vestibular dysfunction and cervical dystonia, abnormal neck proprioception appears to be present in the latter. Treatment of the dystonia can improve balance and gait, as well as reduce the frequency of falls.

Oromandibular Dystonia Causing Recurrent Mandibular Open Lock in Two Adolescents Managed with Botulinum Toxin

Mandibular open lock is a condition in which the patient is unable to close his/her mouth. This is an uncommon condition in children and adolescents that, when recurrent, can severely affect their quality of life. It can also prove to be a challenge for the clinician. When a mandibular open lock is caused by a sustained, recurrent, and involuntary muscle contraction of the inferior lateral pterygoid muscle, it is considered a oromandibular dystonia (OMD). A thorough understanding of the anatomy and function of the temporomandibular joint and the associated masticatory and orofacial muscles is essential to establish the correct diagnosis, allowing the selection of proper treatment. The purpose of this report is to present two cases of OMD in 13-year-old girls managed with onabotulinum toxin A injections into the inferior lateral pterygoid muscle. (J Dent Child 2019;86(1):47-52) <br/> Received May 9, 2018; Last Revision September 3, 2018; Accepted September 4, 2018.

Motor and non-motor determinants of health-related quality of life in young dystonia patients

OBJECTIVES

To systematically investigate the relationship between motor and non-motor symptoms, and health-related quality of life (HR-QoL) in children and young adults with dystonia.

METHODS

In this prospective observational cross-sectional study, 60 patients (6-25 years) with childhood-onset dystonia underwent a multidisciplinary assessment of dystonia severity (Burke-Fahn-Marsden Dystonia Rating Scale, Global Clinical Impression), motor function (Gross Motor Function Measure, Melbourne Assessment of Unilateral Upper Limb Function), pain (visual analogue scale), intelligence (Wechsler Intelligence Scale), executive functioning (Behavior Rating Inventory of Executive Function) and anxiety/depression (Child/Adult Behavior Checklist). Measures were analyzed using a principal component analysis and subsequent multiple regression to evaluate which components were associated with HR-QoL (Pediatric Quality of life Inventory) for total group, and non-lesional (primary) and lesional (secondary) subgroups.

RESULTS

Patients (29 non-lesional, 31 lesional dystonia) had a mean age of 13.6 ± 5.9 years. The principal component analysis revealed three components: 1) motor symptoms; 2) psychiatric and behavioral symptoms; and 3) pain. HR-QoL was associated with motor symptoms and psychiatric and behavioral symptoms (R2 = 0.66) for the total sample and lesional dystonia, but in the non-lesional dystonia subgroup only with psychiatric and behavioral symptoms (R2 = 0.51).

CONCLUSIONS

Non-motor symptoms are important for HR-QoL in childhood-onset dystonia. We suggest a multidisciplinary assessment of motor and non-motor symptoms to optimize individual patient management.

Epidemiology of benign essential blepharospasm: A nationwide population-based retrospective study in Taiwan

IMPORTANCE

This study provides a nationwide, population-based data on the incidence of benign essential blepharospasm in Asian adults.

BACKGROUND

To describe the incidence, patient demographics, and risk factors associated with benign essential blepharospasm.

DESIGN

Population-based retrospective study.

PARTICIPANTS AND SAMPLES

A total of 1325 patients with benign essential blepharospasm were identified.

METHODS

Patients with diagnosis of blepharopsasm between January 2000 and December 2013 were sampled using the Longitudinal Health Insurance Database 2000. Secondary blepharospasm that may be related to neurological, trauma, and ocular surface disease were excluded.

MAIN OUTCOME MEASURED

Multivariate conditional logistic regression was used to estimate the odds ratios for potential risk factors of benign essential blepharospasm.

RESULTS

The mean annual incidence was 0.10‰ (0.07‰ for males, and 0.12‰ for females). The peak incidence was in the 50 to 59-year-old age group (0.19‰). People living in urban regions have more risk of developing blepharospasm comparing to people living in less urban regions (p <0.01). White-collar workers also have higher chance of having blepharospasm (p<0.001). Significant difference between control group and case group in hyperlipidemia (p <0.001), sleep disorders (p <0.001), mental disorders (depression, anxiety, obsessive compulsive disorder) (p <0.001), dry eye-related diseases (dry eye, Sjögren's syndrome) (p <0.001), Parkinson's disease (p <0.004), and rosacea (p <0.021) were also identified.

CONCLUSIONS AND RELEVANCE

Higher level of urbanization, white-collar work, sleep disorders, mental health diseases, dry eye-related diseases, Parkinsonism, and rosacea are possible risk factors for benign essential blepharospasm.

Intrathecal baclofen treatment an option in X-linked adrenoleukodystrophy

BACKGROUND

X-linked adrenoleukodystrophy (X-ALD) is a genetic peroxisomal disorder associated with tissue accumulation of very long chain fatty acids (VLCFAs). In approximately one third of affected males, this causes progressive and irreversible damage to the brain white matter. Progress is often rapid with upper motor neuron damage leading to severe spasticity and dystonia. The increased muscle tone is frequently difficult to alleviate with oral drugs. Here, we describe two patients with X-ALD who have received treatment with intrathecal baclofen pumps (ITB).

CASE STUDY

Both boys had a rapidly progressive cerebral form of the disorder resulting, among other things, in escalating spasticity and dystonia causing severe pain, dramatically reducing their quality of life. Both were treated with a variety of oral medications without adequate relief. Both patients tolerated ITB surgery without complications and the positive clinical effects of treatment with ITB became clear in the following weeks and months, with significantly reduced muscle tone, less pain and better sleep. Moreover, general caretaking became easier.

CONCLUSION

The treatment of spasticity and dystonia in these patients is difficult partly due to the relentless nature of this progressive disorder. In our two patients, ITB has been effective from both a symptomatic and palliative perspective. We recommend that such treatment be considered as an early option for increased muscle tone in boys with the cerebral form of X-ALD.

[Clinical manifestations and genetic diagnosis of paroxysmal kinesigenic dyskinesia]

The clinical manifestations of five children with paroxysmal kinesigenic dyskinesia (PKD) were retrospectively analyzed and their gene mutations were analyzed by high-throughput sequencing and chromosome microarray. The 5 patients consisted of 4 males and 1 female and the age of onset was 6-9 years. Dyskinesia was induced by sudden turn movement, scare, mental stress, or other factors. These patients were conscious and had abnormal posture of unilateral or bilateral extremities, athetosis, facial muscle twitching, and abnormal body posture. The frequency of onset ranged from 3-5 times a month to 2-7 times a day, with a duration of <30 seconds every time. Electroencephalography showed no abnormality in these patients. Three patients had a family history of similar disease. The high-throughput sequencing results showed that a heterozygous mutation in the PRRT2 gene, c.649_650insC (p.R217PfsX8), was found in two patients; the mutation c.436C>T (p.P146S) was found in one patient; a splice site mutation, IVS2-1G>A, was found in one patient. The two mutations c.436C>T and IVS2-1G>A had not been reported previously. The chromosome microarray analysis was performed in one patient with negative results of gene detection, and the chromosome 16p11.2 deletion (0.55 Mb) was observed. Low-dose carbamazepine was effective for treatment of the 5 patients. PKD is a rare neurological disease. The detection of the PRRT2 gene by multiple genetic analysis can help the early diagnosis of PKD.

Stimulating at the right time: phase-specific deep brain stimulation

SEE MOLL AND ENGEL DOI101093/AWW308 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Brain regions dynamically engage and disengage with one another to execute everyday actions from movement to decision making. Pathologies such as Parkinson's disease and tremor emerge when brain regions controlling movement cannot readily decouple, compromising motor function. Here, we propose a novel stimulation strategy that selectively regulates neural synchrony through phase-specific stimulation. We demonstrate for the first time the therapeutic potential of such a stimulation strategy for the treatment of patients with pathological tremor. Symptom suppression is achieved by delivering stimulation to the ventrolateral thalamus, timed according to the patient's tremor rhythm. Sustained locking of deep brain stimulation to a particular phase of tremor afforded clinically significant tremor relief (up to 87% tremor suppression) in selected patients with essential tremor despite delivering less than half the energy of conventional high frequency stimulation. Phase-specific stimulation efficacy depended on the resonant characteristics of the underlying tremor network. Selective regulation of neural synchrony through phase-locked stimulation has the potential to both increase the efficiency of therapy and to minimize stimulation-induced side effects.

Clinical Characteristics of Voice, Speech, and Swallowing Disorders in Oromandibular Dystonia

PURPOSE

To better define the clinical characteristics of idiopathic oromandibular dystonia, we studied voice, speech, and swallowing disorders and their impact on activities of daily living.

METHOD

Fourteen consecutive patients with idiopathic oromandibular dystonia and 14 matched, healthy control subjects were included in the study.

RESULTS

Dysarthria was the most common disorder and its characteristics varied from one patient to another. However, we frequently observed a hyperkinetic, dysarthric profile characterized by imprecise consonants, a rough voice, changes in intensity, and hypernasality. Dysphagia appeared to be slightly less frequent and less disabling than dysarthria. Most patients had difficulty swallowing solids, and the oral phase was particularly problematic. Dysarthria and dysphagia affected activities of daily living in general and the psychological/emotional domain in particular.

CONCLUSIONS

The characteristics of dysarthria in oromandibular dystonia vary significantly from one patient to another due to differences in the set of affected muscles, so each patient should receive a personalized rehabilitation program. Dysarthria was the most prominent symptom, although spasmodic dysphonia was more frequent than expected. Further laboratory-based studies are needed to clarify the mechanisms and consequences of dysphagia in oromandibular dystonia.

Absence of the Autophagy Adaptor SQSTM1/p62 Causes Childhood-Onset Neurodegeneration with Ataxia, Dystonia, and Gaze Palsy

SQSTM1 (sequestosome 1; also known as p62) encodes a multidomain scaffolding protein involved in various key cellular processes, including the removal of damaged mitochondria by its function as a selective autophagy receptor. Heterozygous variants in SQSTM1 have been associated with Paget disease of the bone and might contribute to neurodegeneration in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Using exome sequencing, we identified three different biallelic loss-of-function variants in SQSTM1 in nine affected individuals from four families with a childhood- or adolescence-onset neurodegenerative disorder characterized by gait abnormalities, ataxia, dysarthria, dystonia, vertical gaze palsy, and cognitive decline. We confirmed absence of the SQSTM1/p62 protein in affected individuals' fibroblasts and found evidence of a defect in the early response to mitochondrial depolarization and autophagosome formation. Our findings expand the SQSTM1-associated phenotypic spectrum and lend further support to the concept of disturbed selective autophagy pathways in neurodegenerative diseases.

Single amino acid deletion in transmembrane segment D4S6 of sodium channel Scn8a (Nav1.6) in a mouse mutant with a chronic movement disorder

Mutations of the neuronal sodium channel gene SCN8A are associated with lethal movement disorders in the mouse and with human epileptic encephalopathy. We describe a spontaneous mouse mutation, Scn8a(9J), that is associated with a chronic movement disorder with early onset tremor and adult onset dystonia. Scn8a(9J) homozygotes have a shortened lifespan, with only 50% of mutants surviving beyond 6 months of age. The 3 bp in-frame deletion removes 1 of the 3 adjacent isoleucine residues in transmembrane segment DIVS6 of Nav1.6 (p.Ile1750del). The altered helical orientation of the transmembrane segment displaces pore-lining amino acids with important roles in channel activation and inactivation. The predicted impact on channel activity was confirmed by analysis of cerebellar Purkinje neurons from mutant mice, which lack spontaneous and induced repetitive firing. In a heterologous expression system, the activity of the mutant channel was below the threshold for detection. Observations of decreased nerve conduction velocity and impaired behavior in an open field are also consistent with reduced activity of Nav1.6. The Nav1.6Δ1750 protein is only partially glycosylated. The abundance of mutant Nav1.6 is reduced at nodes of Ranvier and is not detectable at the axon initial segment. Despite a severe reduction in channel activity, the lifespan and motor function of Scn8a(9J/9J) mice are significantly better than null mutants lacking channel protein. The clinical phenotype of this severe hypomorphic mutant expands the spectrum of Scn8a disease to include a recessively inherited, chronic and progressive movement disorder.

[THE INFLUENCE OF A COMBINATION OF MODERN DRUGS NUCLEINAT AND ALFAGIN ON THE CONCENTRATION OF CIRCULATING IMMUNE COMPLEXES AND THEIR MOLECULAR COMPOSITION IN THE SERUM OF PATIENTS WITH IRRITABLE BOWEL SYNDROME ON THE BACKGROUND OF NEUROCIRCULATORY DYSTONIA IN COMPLEX MEDICAL REHABILITATION]

The effect of the combination nucleinat and alfagin in a complex of medical rehabilitation at the level of circulating immune complexes (CIC) in serum of patients and their molecular composition with irritable bowel syndrome (IBS), against neurocirculatory dystonia (NeD). It is established that the combination of nucleinat and alfagin in medical rehabilitation of patients with this comorbid disorders contributes to the normalization of the total concentration of the CEC and their molecular composition, which indicates the validity of the application of the pathogenesis combinations of drugs in complex medical rehabilitation of patients with lBS against NCD.

Refractory Dysphonia Due to Isolated Cricothyroid Muscle Dystonia

OBJECTIVE

To demonstrate the utility of electromyography (EMG) in the evaluation and management of treatment-resistant dysphonia.

METHOD

We report a case of refractory dysphonia in which EMG was used to identify and treat isolated cricothyroid (CT) dystonia.

RESULTS

The patient, a healthy 43-year-old woman, presented with 9 months of progressive hoarseness. Her symptoms were present across vocal tasks but were particularly bothersome while dictating. On presentation, her voice was rated grade 3, roughness 3, breathiness 1, asthenia 0, and strain 3 (G3R3B1A0S3). Videostroboscopy was remarkable for hyperfunction. Voice therapy was not beneficial despite appropriate effort. Microdirect laryngoscopy revealed no evidence of structural pathology. The patient was referred for EMG because of her normal examination and failure to improve with therapy. The CT muscle demonstrated an increased latency of 750 ms in all vocal tasks. One month after CT injection with 3 units of botulinum toxin (BTX), her voice was improved. Perceptual voice evaluation was rated G1R1B0A0S1. Voice Handicap Index improved from 87 to 35.

CONCLUSIONS

In the absence of structural pathology, EMG can be a useful adjunct in the diagnosis of dysphonia that persists despite adequate trials of voice therapy. To our knowledge, this is the only report of laryngeal dystonia due to isolated CT dysfunction successfully treated with BTX.

[THE EFFECTIVENESS OF THE MODERN IMMUNOACTIVE PREPARATION IMMUNOFAN FOR MEDICAL REHABILITATION OF PATIENTS WITH NONALCOHOLIC STEATOHEPATITISIS AGAINST NEUROCIRCULATORY DYSTONIA, AFTER INFECTIOUS MONONUCLEOSIS]

The presence of the expressed changes of cellular immunity, namely T-lymphopenia, disbalance of subpopulation structure of T-lymphocytes with primary downstroke T-helpers/inductor (CD4+), decrease immunoregulatory index CD4/CD8, and functional activity of T-cells is characteristic for the patients with nonalcoholic steatohepatitis, against neurocirculatory dystonia, after infectious mononucleosis. Including in a medical rehabilitation of such patients immunofan promoted practically full correction of the revealed infringements on the part of a cellular link of immunity.

Factors affecting the health-related quality of life of patients with cervical dystonia and impact of treatment with abobotulinumtoxinA (Dysport): results from a randomised, double-blind, placebo-controlled study

OBJECTIVE

To describe the health-related quality of life (HRQOL) burden of cervical dystonia (CD) and report on the HRQOL and patient perception of treatment benefits of abobotulinumtoxinA (Dysport).

DESIGN

The safety and efficacy of a single injection of abobotulinumtoxinA for CD treatment were evaluated in a previously reported international, multicenter, double-blind, randomised trial. HRQOL measures were assessed in the trial and have not been previously reported.

SETTING

Movement disorder clinics in the USA and Russia.

PARTICIPANTS

Patients had to have a diagnosis of CD with symptoms for at least 18 months, as well as a total Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) score of at least 30; a Severity domain score of at least 15; and a Disability domain score of at least 3. Key exclusion criteria included treatment with botulinum toxin type A (BoNT-A) or botulinum toxin type B (BoNT-B) within 16 weeks of enrolment.

INTERVENTIONS

Patients were randomised to receive either 500 U abobotulinumtoxinA (n=55) or placebo (n=61).

PRIMARY AND SECONDARY OUTCOME MEASURES

Efficacy assessments included TWSTRS total (primary end point) and subscale scores at weeks 0, 4, 8, 12; a pain visual analogue scale at weeks 0 and 4; and HRQOL assessed by the SF-36 Health Survey (SF-36; secondary end point) at weeks 0 and 8.

RESULTS

Patients with CD reported significantly greater impairment for all SF-36 domains relative to US norms. Patients treated with abobotulinumtoxinA reported significantly greater improvements in Physical Functioning, Role Physical, Bodily Pain, General Health and Role Emotional domains than placebo patients (p≤0.03 for all). The TWSTRS was significantly correlated with Physical Functioning, Role Physical and Bodily Pain scores, for those on active treatment.

CONCLUSIONS

CD has a marked impact on HRQOL. Treatment with a single abobotulinumtoxinA injection results in significant improvement in patients' HRQOL.

TRIAL REGISTRATION NUMBER

The trial is registered at ClinicalTrials.gov, numbers NCT00257660 and NCT00288509.

Late diagnosis of fucosidosis in a child with progressive fixed dystonia, bilateral pallidal lesions and red spots on the skin

Fucosidosis is a rare lysosomal storage disease. A 14-year-old girl is presented, with recurrent infections, progressive dystonic movement disorder and mental retardation with onset in early childhood. The clinical picture was also marked by mild morphologic features, but absent dysostosis multiplex and organomegaly. MRI images at 6.5 years of age were reminiscent of pallidal iron deposition ("eye-of-the-tiger" sign) seen in neurodegeneration with brain iron accumulation (NBIA) disorders. Progressively spreading angiokeratoma corporis diffusum led to the correct diagnosis. This case extends the scope of clinical and neuroradiological manifestations of fucosidosis.

Responsiveness to botulinum toxin type A in muscles of complex regional pain patients with tonic dystonia

Tonic dystonia of the limbs in complex regional pain syndrome (CRPS) is associated with considerable disability. Treatment options are scarce. Botulinum toxin (BoNT) is sometimes used, but the effect is often said to be disappointing. However, this notion stems from case reports and clinicians' opinions but has never been formally studied. We therefore investigated responsiveness to BoNT in CRPS patients with tonic dystonia. We injected the extensor digitorum brevis (EDB) muscle with BoNT-A in 17 patients with CRPS and tonic dystonia to compare the response between affected and unaffected legs. We also investigated the right legs of 17 healthy controls. Responsiveness was defined as a decrease of the amplitude of the compound muscle action potential (CMAP) of >20% from baseline 2 weeks after BoNT-A injection. We controlled for a temperature effect on BoNT efficacy by measuring skin temperature hourly directly above the EDB muscle in the first 2 weeks. CMAP amplitude decreased >20% after injection on the affected side in 16 of 17 CRPS patients, similar to the response in unaffected legs (12/13) or legs of controls (17/17). The degree of CMAP reduction was significantly smaller in patients than in controls (56.0 ± 22.3 vs. 70.6 ± 14.6%; p = 0.031). This may be due to a lower physical activity level and a greater difficulty to localize the EDB muscle properly in affected legs. The decrease in CMAP amplitude was not related to skin temperature. Contrary to the prevailing opinion, BoNT-A has a normal, although perhaps slightly lower efficacy in CRPS patients with dystonia.

Botulinum Toxin Treatment for Upper Airway Collapse Resulting from Temporomandibular Joint Dislocation Due to Jaw-Opening Dystonia

To examine the effects of botulinum toxin injection application for the treatment of upper airway obstruction due to hyperactive lateral pterygoid muscle contraction, we applied botulinum toxin injection. A 20 year-old male patient had involuntary mouth opening after a diabetic coma. His mouth opened excessively (84 mm) particularly when he was in a nervous or stressed condition. This resulted in a bilateral temporomandibular dislocation and, consequently, upper airway collapse. The differential diagnosis of jaw-opening oromandibular dystonia was made. Botulinum toxin type A was bilaterally injected into the lateral pterygoid muscle. The excessive mouth opening was reduced, and the patient showed no temporomandibular joint (TMJ) dislocation or experienced any further airway collapse after the injections. We successfully applied botulinum toxin to a patient with upper airway obstruction and TMJ dislocation relative to jaw-opening dystonia.

Mandibular angle and coronoid process fracture secondary to orofacial dystonia: report of a case

As the angle is a weak region in the continuity of mandible, so it is more prone to fracture. It has been proven time and again that coronoid fracture results from a strong sudden contraction of temporalis. Muscular forces influence the remodeling of bones. Orofacial dystonia is a centrally mediated disease in which there is an uncontrolled spasmodic contraction of facial and masticatory muscles. This continuous force applied over a long period of time has the potential to unfavorably remodel or weaken bone. A case is presented in which the dystonic action of facial musculature gradually resorbed the bone to such an extent that there was spontaneous fracture at the right angle of mandible as well as the contra lateral coronoid. Management of this fracture posed a challenge at every step eventually leading to resection of the ramus-condyle unit. No case has been reported so far in the literature where dystonic movements have resulted in fracture of the mandible.

Improvement in upper limb function in children with dystonia following deep brain stimulation

BACKGROUND

Childhood dystonia can severely impact upper limb function. Deep brain stimulation (DBS) has been shown to be effective in reducing dystonic symptoms in childhood. Functional recovery following DBS is however not well understood.

AIMS

To explore changes in upper limb function following DBS in paediatric dystonia.

METHODS

Upper limb outcomes, using the Melbourne Assessment of Unilateral Upper Limb Function, are reported in 20 cases of childhood dystonia (unilateral n = 1, four limb n = 19) at 6 and 12 months following DBS.

RESULTS

Improvement in at least in one upper limb was seen in the majority of cases (n = 17, 85%) at 12 months following DBS. Deterioration of scores in both upper limbs was seen in 3 children with progressive disorders. Grouping the children aetiologically, a significant improvement in the dominant hand was obtained for the primary dystonia/dystonia-plus group at both six (p = 0.018) and twelve months (p = 0.012). In secondary dystonia due to a static disorder, improvement was also seen at 6 (p = 0.043) and 12 months (p = 0.046) in the non-dominant hand. No significant change was found in the group of children with progressive disorders.

CONCLUSIONS

DBS has the potential to alter upper limb function in children with primary and secondary dystonia. The dominant hand improved most in children with primary dystonias, with greater improvement in the non-dominant hand in secondary-static cases.