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Thrust manipulation is one of the most commonly used techniques for managing musculoskeletal pain in clinical practice. This involves the application of a high-velocity, low-amplitude force directed to the joints with the intent of achieving joint cavitation. This current case report describes a female in her mid-20s who presented with excessive bilateral and involuntary hand muscle contractions after bilateral thrust manipulation. Dystonia appeared both at rest and during voluntary movements but was aggravated by actions such as finger flexion or spreading and disappeared during sleep. A diagnosis of complex regional pain syndrome (CRPS) type I combined with dystonia was made. Prednisolone administered between 2 and 5 weeks after symptom onset significantly reduced CRPS symptoms, but intramuscular botulinum toxin injection 5 weeks after symptom onset was ineffective at controlling her symptoms. Seven weeks after symptom onset, the patient was administered 2 mg trihexyphenidyl oral twice a day, 2.5 mg diazepam oral twice a day and 5 mg baclofen oral three times a day for 1 month and this significantly reduced dystonia, but complete resolution was not achieved. Clinicians should be aware that dystonia is a rare complication of thrust manipulation., Competing Interests: Declaration of conflicting interestThe authors declare that there are no conflicts of interest.

Juvenile-onset Huntington's disease (HD) is a rare subset of HD with symptom-onset before the age of 18. In contrast to the adult population, children present early-on with behavioral, psychiatric, and cognitive symptoms, in addition to a diverse spectrum of movement disorders. This poses a distinct challenge in diagnosis and management. We here describe the spectrum of movement disorders, accompanied with detailed video recordings, in seven cases of juvenile-onset HD. Our findings highlight early cognitive and behavioral symptoms, preceding motor symptoms. The diverse movement disorder phenotypes included dystonia, Parkinsonism, myoclonus, and chorea, findings which underscore the heterogeneity of presenting symptoms., (© 2024 The Author(s). Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Objective: Although previous studies have described phenomenological diagnoses, they lacked description of aetiological spectrum in patients visiting movement disorders (MD) service. Herein, we classify the MD phenomenology and describe aetiology wise distribution of each phenomenology in patients visiting a tertiary care movement disorders service., Methods: Collected information included demographic profile (age of onset, age at presentation, gender, duration of illness before presentation), predominant MD phenomenology [such as parkinsonism, dystonia, ataxia, tremor, chorea, ballism, myoclonus, tics, stereotypy, restless legs syndrome (RLS) and others], diagnostic evaluations and detected aetiology., Results: This observational study included 1140 MD patients over a span of 5 years. The median (IQR) age of onset was 49 (35-60) years and age at presentation was 54 (40-65) years, with median duration of illness being 36 (18-72) months. Nearly two-third of patients were males (M:F=731:409). Parkinsonism (n=494, 43.3 %) was the most common MD phenomenology observed, followed by dystonia (n=219, 19.2 %), ataxia (n=125, 11 %), tremor (n=118, 10.4 %), myoclonus (n=73, 6.4 %), chorea (n=40, 3.5 %), spasticity (n=22, 1.9 %), tics (n=8, 0.7 %), and RLS (n=8, 0.7 %). Thirty-three (2.9 %) patients were grouped under miscellaneous MDs. Overall, neurodegenerative disorders (57.4 %) were the most common cause of MDs. Parkinson's disease, genetic dystonia, essential tremor, genetic ataxias, hemifacial spasm, and Huntington's disease were the most common aetiologies for parkinsonism, dystonia, tremor, ataxia, myoclonus, and chorea, respectively., Conclusion: Parkinsonism was the most common phenomenology observed in MD patients, and was followed by dystonia, ataxia and tremor. Neurodegenerative disorders were the most common aetiology detected., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Competing Interests: Competing interests: None declared.

Background: Trihexyphenidyl and clonazepam are commonly used to treat dystonia in children with cerebral palsy (CP). However, there is a notable gap in the literature when it comes to studies that combine these first-line agents for the management of dystonia., Methods: This open-label, randomized controlled trial aimed to compare the efficacy of adding oral clonazepam to trihexyphenidyl (THP + CLZ) versus using trihexyphenidyl alone (THP) in reducing the severity of dystonia, as measured by the Barry-Albright Dystonia (BAD) score. The study was conducted over a 12-week therapy period in children with dystonic CP aged two to 14 years., Results: Each group enrolled 51 participants. The THP + CLZ group showed significantly better improvement in dystonia severity at 12 weeks compared with the THP group alone (-4.5 ± 2.9 vs -3.4 ± 1.7, P = 0.02). Furthermore, the THP + CLZ group exhibited superior improvement in the severity of choreoathetosis, upper limb function, pain perception by the child, and quality of life, with P values of 0.02, 0.009, 0.01, and 0.01, respectively. The number of participants experiencing treatment-emergent adverse events was comparable in both groups (P = 0.67). Importantly, none of the participants in any of the groups reported any serious adverse events., Conclusion: A combination of oral THP + CLZ proves to be more efficacious than using THP alone for the treatment of dystonic CP in children aged two to 14 years in terms of reducing the severity of dystonia., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Competing Interests: The authors have no conflict of interest to declare.

The association between dystonia and early-onset epileptic encephalopathy (EOEE) may have a genetic basis. Phosphatidylinositol glycan biosynthesis class A protein (PIGA) germline mutations have been described in the last decade and associated with refractory EOEEs. Dysmorphisms and visceral abnormalities have also been reported. Here, we present the case of a now 8-month-old child who was evaluated for dystonia, visual impairment, and developmental delay at 2 months of age, followed by refractory focal seizures when he was 4 months old. The remaining examination was normal, besides an accelerated linear growth. His brain magnetic resonance and an extensive metabolic investigation failed to show any abnormalities. At 7 months of age, the exome sequencing found a hemizygous PIGA pathogenic variant-c.1352T > C (p.(Ile451Thr). Seizures improved after the association of carbamazepine with levetiracetam and the beginning of the ketogenic diet. To our knowledge, this is the first time the phenotype associated with this specific mutation is described. Our patient had the singularity of manifesting with remarkable dystonia, over 2 months before the onset of seizures. We also point to the utility of the gene sequencing approach in the diagnosis of patients with dystonia and EOEEs, since identification of the genetic cause may help in patient's management and families' empowerment., Competing Interests: None declared., (Thieme. All rights reserved.)

Movement disorders of the stomatognathic system include oromandibular dystonia (OMD), oral dyskinesia, sleep/awake bruxism, functional (psychogenic) stomatognathic movement disorders (FSMDs), tremors, and hemimasticatory spasm (HMS). Most patients first consult dentists or oral surgeons. The differential diagnoses of these involuntary movements require both neurological and dental knowledge and experience, and some of these movement disorders are likely to be diagnosed as bruxism or temporomandibular disorders (TMDs) by dental professionals. However, excepting movement disorder specialists, neurologists may find it difficult to differentially diagnose these disorders. Patients may visit numerous medical and dental specialties for several years until a diagnosis is made. Therefore, movement disorders of the oral region may represent a blind spot between dentistry and medicine.The present narrative review aimed to describe the clinical characteristics and differential diagnoses of some movement disorders, as well as the problems bridging dentistry and medicine. Movement disorders have the following characteristic clinical features: OMD - task specificity, sensory tricks and the morning benefit; FSMDs - inconsistent and incongruous symptoms, spreading to multiple sites and the lack of sensory tricks; and HMS - the paroxysmal contraction of unilateral jaw-closing muscles, the persistence of symptoms during sleep and the loss of a silent period. A careful differential diagnosis is essential for the adequate and effective treatment of each involuntary movement. Refining the latest definition of bruxism may be necessary to prevent the misdiagnosis of involuntary movements as bruxism.Both dental and medical professionals should take an interest in the movement disorders of the stomatognathic system, and these disorders should be diagnosed and treated by a multidisciplinary team.

Background: Subacute sclerosing panencephalitis (SSPE) is a complication of measles, occurring after a latency of 4-10 years. It continues to occur in developing countries although resurgence is being reported from developed countries. Characteristic features include progressive neuropsychiatric issues, myoclonus, seizures, movement disorders and visual impairment. Electroencephalography (EEG) typically shows periodic generalized discharges, and elevated CSF anti-measles antibodies are diagnostic. Movement disorders are being increasingly recognized as part of the clinical spectrum, and range from hyperkinetic (chorea, dystonia, tremor, tics) to hypokinetic (parkinsonism) disorders and ataxia., Objectives: This article aims to comprehensively review the spectrum of movement disorders associated with SSPE., Methods: A literature search was conducted in PubMed and EMBASE databases in December 2023 and articles were identified for review., Results: Movement disorders reported in SSPE included hyperkinetic (chorea, dystonia, tremor and tics), hypokinetic (parkinsonism), ataxia and extraocular movement disorders. Myoclonus, a core clinical feature, was the most frequent "abnormal movement." Movement disorders were observed in all clinical stages, and could also be a presenting feature, even sans myoclonus. Hyperkinetic movement disorders were more common than hypokinetic movement disorders. An evolution of movement disorders was observed, with ataxia, chorea and dystonia occurring earlier, and parkinsonism later in the disease. Neuroradiological correlates of movement disorders remained unclear., Conclusion: A wide spectrum of movement disorders was observed throughout the clinical stages of SSPE. Most data were derived from case reports and small case series. Multicentric longitudinal studies are required to better delineate the spectrum and evolution of movement disorders in SSPE., (© 2024 International Parkinson and Movement Disorder Society.)

Background: Movement disorders in children and adolescents with dyskinetic cerebral palsy (CP) are commonly assessed from video recordings, however scoring is time-consuming and expert knowledge is required for an appropriate assessment., Objective: To explore a machine learning approach for automated classification of amplitude and duration of distal leg dystonia and choreoathetosis within short video sequences., Methods: Available videos of a heel-toe tapping task were preprocessed to optimize key point extraction using markerless motion analysis. Postprocessed key point data were passed to a time series classification ensemble algorithm to classify dystonia and choreoathetosis duration and amplitude classes (scores 0, 1, 2, 3, and 4), respectively. As ground truth clinical scoring of dystonia and choreoathetosis by the Dyskinesia Impairment Scale was used. Multiclass performance metrics as well as metrics for summarized scores: absence (score 0) and presence (score 1-4) were determined., Results: Thirty-three participants were included: 29 with dyskinetic CP and 4 typically developing, age 14 years:6 months ± 5 years:15 months. The multiclass accuracy results for dystonia were 77% for duration and 68% for amplitude; for choreoathetosis 30% for duration and 38% for amplitude. The metrics for score 0 versus score 1 to 4 revealed an accuracy of 81% for dystonia duration, 77% for dystonia amplitude, 53% for choreoathetosis duration and amplitude., Conclusions: This methodology study yielded encouraging results in distinguishing between presence and absence of dystonia, but not for choreoathetosis. A larger dataset is required for models to accurately represent distinct classes/scores. This study presents a novel methodology of automated assessment of movement disorders solely from video data., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Pyruvate dehydrogenase complex (PDC) deficiency is a genetic mitochondrial disease mostly associated with severe lactic acidosis, rapid progression of neurological symptoms and death during childhood. We present a 33-year-old male with PDC deficiency caused by a Val262Leu mutation in PDHA1gene. He demonstrated generalized dystonia affecting trunk and upper extremities and paraparesis as the most significant features, with onset of symptoms at age 8. Brain MRI showed bilaterally increased signal within the globus pallidus, typical of Leigh syndrome. A periodic lactate increase in serum and cerebrospinal fluid was detected. We describe a case of pyruvate dehydrogenase deficiency being diagnosed only 25 years after the onset of symptoms and highlight PDHC deficiency as a possible cause of treatable dystonia in childhood, which may respond well to thiamine and levodopa treatment., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Subacute Sclerosing Panencephalitis (SSPE) typically presents with periodic myoclonus; however, a spectrum of movement disorders including dystonia, chorea, tremor, and parkinsonism have also been described. This review aims to evaluate the array of movement disorders in SSPE, correlating them with neuroimaging findings, disease stages, and patient outcomes., Methods: A comprehensive review of published case reports and case series was conducted on patients with SSPE exhibiting movement disorders other than periodic myoclonus. PRISMA guidelines were followed, and the protocol was registered with PROSPERO (2023 CRD42023434650). A comprehensive search of multiple databases yielded 37 reports detailing 39 patients. Dyken's criteria were used for SSPE diagnosis, and the International Movement Disorders Society definitions were applied to categorize movement disorders., Results: The majority of patients were male, with an average age of 13.8 years. Approximately, 80% lacked a reliable vaccination history, and 39% had prior measles infections. Dystonia was the most common movement disorder (49%), followed by parkinsonism and choreoathetosis. Rapid disease progression was noted in 64% of cases, with a disease duration of ≤6 months in 72%. Neuroimaging showed T2/FLAIR MR hyperintensities, primarily periventricular, with 26% affecting the basal ganglia/thalamus. Brain biopsies revealed inflammatory and neurodegenerative changes. Over half of the patients (56%) reached an akinetic mute state or died., Conclusion: SSPE is associated with diverse movement disorders, predominantly hyperkinetic. The prevalence of dystonia suggests basal ganglia dysfunction., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2024 The Author(s).)

Background: Heterozygous loss-of-function variants in CHD8 have been associated with a syndromic neurodevelopmental-disease spectrum, collectively referred to as CHD8-related neurodevelopmental disorders. Several different clinical manifestations, affecting neurodevelopmental and systemic domains, have been described, presenting with highly variable expressivity. Some expressions are well established and comprise autism spectrum disorders, psychomotor delay with cognitive impairment, postnatal overgrowth with macrocephaly, structural brain abnormalities, gastrointestinal disturbances, and behavioral and sleep-pattern problems. However, the complete phenotypic spectrum of CHD8-related disorders is still undefined. In 2021, our group described two singular female patients with CHD8-related neurodevelopmental disorder and striking dystonic manifestations, prompting the suggestion that dystonia should be considered a possible component of this condition., Case Series Presentation: We describe three additional unrelated female individuals, each carrying a different CHD8 frameshift variant and whose clinical presentations were primarily characterized by young-onset dystonia. Their dystonic manifestations were remarkably heterogeneous and ranged from focal, exercise-dependent, apparently isolated forms to generalized permanent phenotypes accompanied by spasticity and tremor. Neurocognitive impairment and autistic behaviors, typical of CHD8-related disorders, were virtually absent or at the mild end of the spectrum., Conclusions: This work validates our previous observation that dystonia is part of the phenotypic spectrum of CHD8-related neurodevelopmental disorders with potential female preponderance, raising new challenges and opportunities in the diagnosis and management of this condition. It also highlights the importance of in-depth neurologic phenotyping of patients carrying variants associated with neurodevelopmental disorders, as the connection between neurodevelopmental and movement disorders is proving closer than previously appreciated., (© 2024. The Author(s).)

Introduction: Dystonia is a painful OFF-related complication in Parkinson's disease (PD) with limited treatment options., Methods: Post-hoc analysis using pooled data from two extended-release amantadine pivotal trials and follow-on open-label extension. Dystonia was assessed using the Unified Dyskinesia Rating Scale (UDysRS) Part 2 and the Movement Disorder Society-Unified PD Rating Scale (MDS-UPDRS) item 4.6., Results: Of 196 participants, 119 (60.7%) reported OFF-related dystonia at baseline per UDysRS. Twelve-week treatment with extended-release amantadine improved OFF dystonia (treatment differences vs placebo: UDysRS Part 2, -1.0 [-1.9,-0.1]; p = 0.03 and MDS-UPDRS Item 4.6, -0.3 [-0.6,-0.05]; p = 0.02). There was no correlation between changes in OFF time and changes in OFF dystonia. Double-blind improvements in OFF dystonia were sustained throughout the 2-year follow-up., Conclusions: Extended-release amantadine yielded a sustained reduction in OFF-related dystonia in PD patients that was independent from a reduction in OFF time. A randomized controlled trial is warranted to confirm these findings., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Alberto J. Espay has received grant support from the NIH and the Michael J Fox Foundation; personal compensation as a consultant/scientific advisory board member for Neuroderm, Neurocrine, Amneal, Acadia, Acorda, Bexion, Kyowa Kirin, Sunovion, Supernus (formerly, USWorldMeds), Avion Pharmaceuticals, and Herantis Pharma; personal compensation as honoraria for speakership for Avion; and publishing royalties from Lippincott Williams & Wilkins, Cambridge University Press, and Springer. He cofounded REGAIN Therapeutics (a biotech start-up developing nonaggregating peptide analogues as replacement therapies for neurodegenerative diseases) and is co-owner of a patent that covers synthetic soluble nonaggregating peptide analogues as replacement treatments in proteinopathies. Jill Ostrem reports grant support from the NIH, Parkinson Foundation, Biogen, Medtronic, Boston Scientific, Neuroderm, Rune; personal compensation as a consultant for Abbott, Acorda, Supernus, and Jazz Pharmaceuticals. Andrea E. Formella is employed by Supernus Pharmaceuticals Inc. Caroline Tanner reports grant support from the NIH, the Michael J Fox Foundation, the Department of Defense, the Parkinson Foundation, the Marcus Program in Precision Medicine, Gateway LLC, Roche-Genentech, Biogen, Bioelectron Technology Corporation; personal compensation as a consultant/scientific advisory board/data & safety monitoring board member for CNS Ratings, Cadent, Adamas, Biogen, Acorda, Amneal, Neurocrine, Kyowa Kirin, Jazz/Cavion and the Australian Parkinson's Mission., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Posterior interosseous neuropathy is an uncommon cause of peripheral dystonia., Case Report: A 62-year-old man awakened and noticed right finger drop. A neurological examination revealed posterior interosseous neuropathy with dystonia-like finger movements. Abnormal movements were predominantly observed in the right thumb, ring finger, and little finger. Within 2 weeks, the muscle weakness in the right fingers had completely improved. However, a brief abnormal posture of the right thumb was persistent., Discussion: The residual abnormal posture of the right thumb may reflect pre-existing motor control abnormalities, which may have contributed to the onset of posterior interosseous neuropathy-associated peripheral dystonia., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2024 The Author(s).)

Although manifesting contrasting phenotypes, Parkinson's disease and dystonia, the two most common movement disorders, can originate from similar pathophysiology. Previously, we demonstrated that lesioning (silencing) of a discrete dorsal region in the globus pallidus (rodent equivalent to globus pallidus externa) in rats and produced parkinsonism, while lesioning a nearby ventral hotspot-induced dystonia. Presently, we injected fluorescent-tagged multi-synaptic tracers into these pallidal hotspots (n = 36 Long Evans rats) and permitted 4 days for the viruses to travel along restricted connecting pathways and reach the motor cortex before sacrificing the animals. Viral injections in the Parkinson's hotspot fluorescent labeled a circumscribed region in the secondary motor cortex, while injections in the dystonia hotspot labeled within the primary motor cortex. Custom probability mapping and N200 staining affirmed the segregation of the cortical territories for Parkinsonism and dystonia to the secondary and primary motor cortices. Intracortical microstimulation localized territories specifically to their respective rostral and caudal microexcitable zones. Parkinsonian features are thus explained by pathological signaling within a secondary motor subcircuit normally responsible for initiation and scaling of movement, while dystonia is explained by abnormal (and excessive) basal ganglia signaling directed at primary motor corticospinal transmission., (© 2024 The Authors. Journal of Neuroscience Research published by Wiley Periodicals LLC.)

Background: Early onset ataxia (EOA) and Early Onset Dystonia (EOD) are movement disorders developing in young people (age <25 per definition). These disorders result from dysfunctional networks involving the cerebellum and basal ganglia. As these structures are also important for cognition, cognitive deficits can be expected in EOA and EOD. EOA and EOD sometimes co-occur, but in those cases the predominant phenotype is determining. A pending question is whether predominantly EOA and EOD have different profiles of cognitive impairment., Objectives: We investigated whether cognitive functions were impaired in patients with either predominant EOA or predominant EOD and whether cognitive profiles differed between both patient groups., Methods: The sample consisted of 26 EOA and 26 EOD patients with varying etiology but similar duration and severity of the disorder. Patient samples were compared to a group of 26 healthy controls, all matched on age and gender. All participants underwent neuropsychological testing for verbal intelligence, memory, working memory, attention/cognitive speed, executive functions, emotion recognition and language., Results: EOA and EOD patients both performed significantly worse than healthy controls on tests of verbal intelligence, working memory and executive functions. Additionally, attention/cognitive speed and emotion recognition were impaired in the EOA group. Compared to EOD, EOA patients performed worse on attention/cognitive speed and verbal intelligence., Conclusions: Our results show overall similar profiles of cognitive deficits in both patient groups, but deficits were more pronounced in the patients with EOA. This suggests that more severe cognitive impairment is related to more severe cerebellar network dysfunction., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Maraike Coenen reports financial support was provided by Phelphs Stichting voor spastici. Hendriekje Eggink reports financial support was provided by Phelphs Stichting voor spastici. Maraike Coenen reports financial support was provided by Dystonia Foundation. Maraike Coenen reports financial support was provided by Foundation of Friends of Beatrix Children’s Hospital. Deborah Sival serves in the editorial board of EJPN., (© 2024 Published by Elsevier Ltd on behalf of European Paediatric Neurology Society.)

Abductor laryngeal dystonia (ABLD) is a rare neurological voice disorder which results in sporadic opening of the vocal folds during speech. Etiology is unknown, and to date there is no identified effective behavioral treatment for it. It is hypothesized that LSVT LOUD®, which was developed to treat dysphonia secondary to Parkinson's disease, may have application to speakers with ABLD to improve outcomes beyond that with botulinum neurotoxin (BoNT) treatment alone. The participant received one injection of BoNT in each vocal fold 2 to 3 months prior to initiating intensive voice therapy via teletherapy. Objective measures of vocal loudness (dB sound pressure level), maximum phonation time, and high/low pitch frequency (Hz) were recorded in all treatment sessions and follow-up sessions. Over the course of treatment, the participant showed steady gains in phonation time, volume, pitch range, and vocal quality with a substantial reduction in aphonic voice breaks by the end of the treatment program. Perceptual symptoms of ABLD were nearly undetectable by the participant and the clinicians up to 12 months posttreatment, with no additional BoNT injections. The results suggest that LSVT LOUD® following BoNT was effective, with long-lasting improvement in vocal function, for this speaker with ABLD., Competing Interests: The authors declare that there are no relevant conflicts of interest at the time of publication., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).)

Introduction: Invasive neuromodulation interventions such as deep brain stimulation (DBS) and vagal nerve stimulation (VNS) are important treatments for movement disorders and epilepsy, but literature focused on young patients treated with DBS and VNS is limited. This retrospective study aimed to examine naturalistic outcomes of VNS and DBS treatment of epilepsy and dystonia in children, adolescents, and young adults., Methods: We retrospectively assessed patient demographic and outcome data that were obtained from electronic health records. Two researchers used the Clinical Global Impression scale to retrospectively rate the severity of neurologic and psychiatric symptoms before and after patients underwent surgery to implant DBS electrodes or a VNS device. Descriptive and inferential statistics were used to examine clinical effects., Results: Data from 73 patients were evaluated. Neurologic symptoms improved for patients treated with DBS and VNS (p < .001). Patients treated with DBS did not have a change in psychiatric symptoms, whereas psychiatric symptoms worsened for patients treated with VNS (p = .008). The frequency of postoperative complications did not differ between VNS and DBS groups., Conclusion: Young patients may have distinct vulnerabilities for increased psychiatric symptoms during treatment with invasive neuromodulation. Child and adolescent psychiatrists should consider a more proactive approach and greater engagement with DBS and VNS teams that treat younger patients., (© 2024 The Authors. Brain and Behavior published by Wiley Periodicals LLC.)

Background: Essential tremor (ET) is characterized by action tremor of the upper limbs, head tremor and voice tremor. Dystonic tremor (DT) is produced by muscle contractions in a body affected by dystonia. Deep brain stimulation (DBS) of ventral intermediate nucleus of the thalamus (VIM) is the most well-known advanced treatment for medication-refractory tremor. However, decline in efficacy overtime has led to explore other targets. This study aimed to measure the efficacy of bilateral dual targeting ViM/caudal Zona Incerta (cZI) stimulation on tremor control. A secondary aim was to evaluate if there was a difference in the efficacy between ET and DT., Methods: 36 patients were retrospectively recruited at the Walton NHS Foundation Trust, Liverpool, UK. Patients were assessed pre-operatively, and then at 1-year, 3-years, and 5-years post-operatively with the following scales: Fahn-Tolosa-Marin tremor rating (FTMTR) scale, EuroQol-5D, and Hospital Anxiety and Depression Scale., Results: Bilateral ViM-cZI DBS significantly improved overall tremor score by 45.1% from baseline to 3-years post-operatively (p < 0.001). It continued to show improvement in overall FTMTR score by 30.7% at 5-years but this failed to meet significance. However, there was no significant improvement of mood or quality of life (QoL) scores. ET group on average showed a significant better clinical outcome compared to the DT group (p > 0.001)., Conclusions: Our study found that bilateral ViM-cZI DBS treatment had a favourable effect on motor symptoms sustained over the 5-years in tremor patients, especially in ET group. There was limited effect on mood and QoL with similar trends in outcomes for both tremor types., Competing Interests: Declaration of competing interest All authors declare we have no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Stiff-person syndrome (SPS) is a rare neurological condition that frequently affects adults, with the neurologist diagnosing only one or two cases during his or her career. Reports of paediatric SPS are exceedingly rare, with less than 20 cases described in the literature.The patient presented was initially diagnosed with a functional movement disorder then a genetic dystonia, with a poor response to treatment trials and negative genetic testing. Consideration of Wilson's disease was refuted with non-supportive investigations and assessments.We aim to present the long road to diagnosing our first paediatric patient with SPS, who presented in middle childhood., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Foot dystonia occurs in patients with Parkinson's disease (PD) and leads to pain, malformation, and difficulty with walking. Botulinum toxin injections may be effective for foot dystonia, but the extent of improvement and effects on motor function are unclear., Methods: In this study, we performed botulinum toxin injections for foot dystonia in 25 patients with PD. At 3 weeks and 3 months post-infection, we assessed changes in plantar pressure distribution utilizing the Pressure Plate system; dystonia using the Modified Ashworth Spasm score; pain using the visual analog scale (VAS) score; and lower extremity function using the Calf-raise Senior (CRS) test, Timed Up and Go (TUG) test, and gait parameters (eg, stride length, step length)., Results: We found improved Modified Ashworth Spasm score (p < 0.01) and VAS score (p < 0.01) post-injection. CRS test score (3 weeks, p = 0.006; 3 months, p = 0.068), stride length (3 weeks, p = 0.012; 3 months, p = 0.715), and step length (3 weeks, p = 0.011; 3 months, p = 0.803) also improved. Plantar pressure distribution improved after botulinum toxin injection (metatarsal 1, 3 weeks, p = 0.031; 3 months, p = 0.144; metatarsal 2, 3 weeks, p = 0.049; 3 months, p = 0.065; metatarsal 3, 3 weeks, p = 0.002; 3 months, p = 0.017; metatarsal 4, 3 weeks, p = 0.017; 3 months, p = 0.144; medial heel, 3 weeks, p = 0.01; 3 months, p = 0.395; lateral heel, 3 weeks, p = 0.035; 3 months, p = 0.109)., Conclusion: Botulinum toxin injection for foot dystonia in patients with PD can reduce spasms and pain and normalize plantar pressure distribution, which improves balance and lower extremity function., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Objective: To determine how caregivers describe dystonia in people with cerebral palsy (CP)., Methods: In this prospective cohort study, paper surveys were administered to caregivers between September 7, 2021 and October 28, 2021 during CP Center visits at a large tertiary care center. Caregivers were asked to describe involuntary movements triggered by voluntary movement or triggered by tactile stimulation in the people with CP they cared for. Their CP Center medical provider separately assessed people with CP for dystonia. Movement features described exclusively by caregivers of people with CP and dystonia were determined using conventional content analysis., Results: 113 caregivers responded on behalf of 56 people with and 57 people without dystonia. If caregivers noted that both voluntary movement and tactile stimulation triggered involuntary movements, that had a 92% positive predictive value for a dystonia diagnosis. Movement features exclusively described in people with CP and dystonia included: (1) stiffening, tensing, or tightening (15% of respondents); (2) involvement of the head (10%), torso (5%), or feet (5%); and (3) triggers of stretching (12.5%), excitement (5%), or transfers (5%)., Interpretation: In addition to a thorough exam, asking caregivers of people with CP to describe involuntary movements triggered by voluntary movement or tactile stimulation may inform clinical dystonia diagnosis., (© 2023 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Objective: Paraneoplastic neurological syndromes (PNS) are rare disorders associated with various onconeuronal antibodies. Anti-Ri antibodies (ANNA-2) are typically found in patients with opsoclonus myoclonus syndrome (OMS) and ataxia., Case Report: We present an anti-Ri antibody-positive 77-year-old woman with subacute progressive bilateral cranial nerve VI palsy, gait disturbance and jaw dystonia. MRI of the brain showed hyperintense signals on T 2 bitemporal without contrast enhancement. Cerebrospinal fluid (CSF) examination exhibited mild pleocytosis of 13 cells/µl and positive oligoclonal bands. CSF was overall inconspicuous for a malignant or inflammatory etiology. Immunofluorescence analysis revealed anti-Ri antibodies in both serum and CSF. Subsequent diagnostic work up resulted in a newly diagnosed ductal carcinoma of the right breast. PNS in this case partially responded to the anti-tumor therapy., Conclusion: This case shows similarities with recently published anti-Ri syndromes, which might form a distinct triad within the anti-Ri spectrum., (© 2023. The Author(s).)

Introduction: Magnetic resonance guided focused ultrasound (MRgFUS) thalamotomy is an effective treatment for drug-resistant tremor. The most frequent side effects are ataxia, gait disturbance, paresthesias, dysgeusia, and hemiparesis. Here, we report the first case of thalamic hand dystonia rapidly occurring after MRgFUS thalamotomy of the ventral intermediate nucleus (V.im)., Case Presentation: MRgFUS thalamotomy was performed in a 60-year-old left-handed patient for his disabling medically refractory essential tremor. The intervention resulted in a marked reduction of his action tremor. However, the patient developed an unvoluntary abnormal posture in his left hand a few days after the procedure with difficulty holding a cigarette between his fingers. Brain MRI revealed the expected MRgFUS lesion within the right V.im as well as an extension of the lesion anteriorly to the V.im in the ventro-oralis nucleus. Tractography showed that the lesion disrupted the dentato-rubro-thalamic tract as expected with a lesion suppressing tremor. However, the lesion also was interrupted fibers connecting to the superior frontal and pre-central cortices (primary motor cortex, premotor cortex, and supplementary area). We hypothesized that the interventional MRgFUS thalamotomy was slightly off target, which induced a dysfunction within the cortico-striato-thalamo-cortical network and the cerebello-thalamo-cortical pathway reaching a sufficient threshold of basal ganglia/cerebellum circuitry interference to induce dystonia., Conclusion: This rare side effect emphasizes the risk of imbalance within the dystonia network (i.e., basal ganglia-cerebello-thalamo-cortical circuit) secondary to V.im thalamotomy., (© 2024 S. Karger AG, Basel.)

Background and Objectives: Laryngeal dystonia (LD) is a focal dystonia affecting adductor and/or abductor muscles of the larynx. It can be isolated or may spread to extra laryngeal muscles. The aim of this study was to report the characteristics of LD over time in a large single-center study with a long follow-up., Methods: Retrospective review of patients with LD referred to our institution between 1991 and 2021. Demographic data, time to diagnosis, type of LD, follow-up and spread of dystonia [SD] were recorded. Risk factors for spread of dystonia during follow-up were analyzed., Results: Over the 30-year period, 516 patients (77.3 % female, median age 50 years, range 5-87 years) were analyzed. Three hundred and fifteen patients (61 %) had adduction laryngeal dystonia, 136 patients (26.4 %) had abduction laryngeal dystonia, 46 patients (8.9 %) had adductor respiratory laryngeal dystonia, 12 patients (2.3 %) had mixed laryngeal dystonia, and seven patients (1.4 %) had singer's laryngeal dystonia. A previous history of dystonia was found in 47 patients (9.1 %). A laryngeal tremor was found in 68 patients (13.2 %). Since the onset of symptoms, LD was diagnosed after a median of 3 years (IQR: 1.0, 7.0). SD occurred in 55 patients (10.7 %) after a median time of 4 year (IQR: 1.5, 13.0). Patients with mixed laryngeal dystonia had higher probability of SD (p = 0.018)., Discussion: This study reports a large European study of LD, with a long follow-up. SD occurred in 10.5 % of patients. Patients with mixed laryngeal dystonia had a higher probability of SD. A close follow-up may be recommended for patients with mixed laryngeal dystonia., Competing Interests: Declaration of competing interest G. Dupuch reports no disclosures relevant to the manuscript. M. Mailly reports no disclosures relevant to the manuscript. J. Guillaume reports no disclosures relevant to the manuscript. M. Daval reports no disclosures relevant to the manuscript. D. Ayache reports no disclosures relevant to the manuscript. D. Brasnu reports no disclosures relevant to the manuscript. Data collected for the study, including individual participant data and a data dictionary defining each field in the set, will be made available to others. All other data will be made available. These data will be available with publication. The data will be made available at guillaume.dupuch1@gmail.com (first author email address)., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: Childhood dystonia is often nonresponsive to medications, and refractory cases are increasingly being treated with deep brain stimulation (DBS). However, many have noted that there is little consensus about when DBS should be offered, and there has been little examination of clinicians' decision-making process when determining whether to offer DBS for childhood dystonia., Objectives: This study aimed to identify and examine the factors considered by pediatric movement disorder specialists before offering DBS., Materials and Methods: Semistructured interviews (N = 29) with pediatric dystonia clinicians were conducted, transcribed, and coded. Using thematic content analysis, nine central themes were identified when clinicians were asked about key factors, clinical factors, and psychosocial factors considered before offering pediatric DBS., Results: Clinicians identified nine main factors. Five of these were classified primarily as clinical factors: early intervention and younger age (raised by 86% of respondents), disease progression and symptom severity (83%), etiology and genetic status (79%), clinicians' perceived risks and benefits of DBS for the patient (79%), and exhaustion of other treatment options (55%). The remaining four were classified primarily as psychosocial factors: social and family support (raised by 97% of respondents), patient and caregiver expectations about outcomes and understanding of DBS treatment (90%), impact of dystonia on quality of life (69%), and financial resources and access to care (31%)., Conclusions: Candidacy determinations, in this context, are complicated by an interrelation of clinical and psychosocial factors that contribute to the decision. There is potential for bias when considering family support and quality of life. Uncertainty of outcomes related to the etiology of dystonia makes candidacy judgments challenging. More systematic examination of the characteristics and criteria used to identify pediatric patients with dystonia who can significantly benefit from DBS is necessary to develop clear guidelines and promote the well-being of these children., (Copyright © 2021 International Neuromodulation Society. Published by Elsevier Inc. All rights reserved.)

Musician's Dystonia (MD) is a task-specific movement disorder that results in an involuntary cramping of muscles involved in playing an instrument such as the upper limbs or the embouchure. It is usually painless and occurs in general only at the instrument. The pathophysiology of MD is not completely understood. The present study aimed at assessing differences in practice behaviors between pianists affected by MD and Healthy Controls (HC) in the years preceding the onset of the disease. Thus, we investigated to what extent practice quantity can be considered a trigger of Musicians' Dystonia. The results showed that despite comparable practice behaviors in childhood, MD pianists incremented the amount of daily practice to a greater extent than their healthy colleagues, especially in the second and in the third decade of life. Thus, subsequent logistic regression analysis showed that high amounts of daily practice might significantly increase the risk of developing MD. Furthermore, gender-related differences in practice behaviors across groups were identified, indicating that male pianists from the MD group might not have practiced significantly more than HC male pianists before the onset of the disease. To the authors' knowledge, these are the first empirical evidence of the role of dysfunctional practice behaviors in triggering MD, which has clinical and educational implications., (© 2023. The Author(s).)

Background:  Hereditary or familial spastic paraplegias (SPG) comprise a group of genetically and phenotypically heterogeneous diseases characterized by progressive degeneration of the corticospinal tracts. The complicated forms evolve with other various neurological signs and symptoms, including movement disorders and ataxia., Objective:  To summarize the clinical descriptions of SPG that manifest with movement disorders or ataxias to assist the clinician in the task of diagnosing these diseases., Methods:  We conducted a narrative review of the literature, including case reports, case series, review articles and observational studies published in English until December 2022., Results:  Juvenile or early-onset parkinsonism with variable levodopa-responsiveness have been reported, mainly in SPG7 and SPG11. Dystonia can be observed in patients with SPG7, SPG11, SPG22, SPG26, SPG35, SPG48, SPG49, SPG58, SPG64 and SPG76. Tremor is not a frequent finding in patients with SPG, but it is described in different types of SPG, including SPG7, SPG9, SPG11, SPG15, and SPG76. Myoclonus is rarely described in SPG, affecting patients with SPG4, SPG7, SPG35, SPG48, and SPOAN (spastic paraplegia, optic atrophy, and neuropathy). SPG4, SPG6, SPG10, SPG27, SPG30 and SPG31 may rarely present with ataxia with cerebellar atrophy. And autosomal recessive SPG such as SPG7 and SPG11 can also present with ataxia., Conclusion:  Patients with SPG may present with different forms of movement disorders such as parkinsonism, dystonia, tremor, myoclonus and ataxia. The specific movement disorder in the clinical manifestation of a patient with SPG may be a clinical clue for the diagnosis., Competing Interests: There is no conflict of interest to declare., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution 4.0 International License, permitting copying and reproduction so long as the original work is given appropriate credit (https://creativecommons.org/licenses/by/4.0/).)

Classical homocystinuria is caused by pathogenic variants in the CBS gene leading to a deficiency of the vitamin B6-dependent enzyme cystathionine beta synthase. The disease is typically associated with high blood homocysteine concentrations. Clinical features include developmental delay/intellectual disability, psychiatric problems, thromboembolism, lens dislocation, and marfanoid habitus. We report on a child with classical homocystinuria presenting with acute episodes of dystonia and symmetrical basal ganglia abnormalities mimicking a mitochondrial disease. After starting treatment with vitamin B6, homocysteine levels rapidly normalized and dystonic episodes did not re-occur. Moreover, brain-imaging findings almost completely disappeared. The case illustrates that homocystinuria should be considered as a treatable differential diagnosis of dystonia., (© 2023 SSIEM.)

Rationale: Pantothenate kinase-associated neurodegeneration (PKAN), also called Hallervorden-Spatz syndrome, is a rare autosomal recessive disease associated with brain iron accumulation and characterized by progressive dystonia, dementia, and dysarthria symptoms. PKAN, caused by a defective pantothenate kinase 2 (PANK2) gene, is the most common neurodegeneration with a brain iron accumulation (NBIA) group. The "eye of the tiger" sign in the magnetic resonance imaging demonstrated a bilateral hyperintense signal in the basal ganglia region on T2-weighted images, which is a characteristic feature of the diagnosis. PKAN is classified into 2 main types. The early-onset type (classic type) with rapid progression is characterized by symptoms of gait impairment and dystonia leading to loss of ambulation in early childhood. In the later-onset type (atypical type), slow progression usually takes place in the second decade of life with symptoms of neurodegeneration, dystonia, dysarthria, rigidity, choreoathetosis, and motor impairment. Until now, PKAN patients have only been reported in a few countries in Asia such as China, Korea, India, Iran, Taiwan, and Thailand., Patient Concerns: Here we report the first case of PKAN in Vietnam. The patient had a late onset but the disease progresses rapidly with symptoms of dyskinesia, dysphagia, and difficulty speaking., Diagnoses: Pantothenate kinase-associated neurodegeneration., Interventions: Whole exome sequencing was performed to identify heterozygous mutations in the PANK2 gene (NM&#95;153638.4) (c.856C>T, p.Arg286Cys and c.1351C>T, p.Arg451Ter) that has been confirmed as the cause of the disease., Outcomes: In this study, the first Vietnamese patient with late-onset PKAN was diagnosed by the whole exome sequencing method., Lessons: The patient's case marks an important milestone for the first case in Vietnam. The results of the study will provide a scientific basis for clinicians in the diagnosis and genetic counseling of patients., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Paroxysmal autonomic instability with dystonia syndrome (PAIDS) is a rare and life-threatening complication of neurologic diseases. We report the case of a 20-year-old male with acute severe brain damage from tuberculous meningitis, who eventually developed paroxysmal episodes of spontaneous and inducible tachycardia, tachypnea, hypertension, and decerebrate posturing. We diagnosed the patient as suffering from paroxysmal autonomic instability with dystonia syndrome. The unavailability of morphine and the prohibitive cost of prolonged fentanyl use led to a trial of gabapentin, clonazepam, and propranolol for the patient, resulting in symptom resolution. Brain injury causes dysfunction of autonomic centers leading to paroxysmal autonomic instability with dystonia syndrome. Management includes minimizing stimulation and pharmacotherapy with preventive and abortive medications. Alternatives like gabapentin, propranolol and clonazepam were effective in treating the paroxysmal episodes, proving that they may have a role in resource limited settings. PAIDS requires urgent recognition and treatment to prevent further complications and death., Competing Interests: No competing interests were disclosed., (Copyright: © 2023 Dichoso LP et al.)

Recent focus on improving the recognition of dystonia in cerebral palsy (DCP) has highlighted the need for more effective treatments. Evidence supports improved functional outcomes with early interventions for patients with cerebral palsy, but it is not known which interventions are most effective for DCP. Current pharmacologic recommendations for DCP are based largely on anecdotal evidence, with medications demonstrating minimal to moderate improvements in dystonia and variable efficacy between patients. Patients, families, and clinicians have identified the need for new and improved treatments in DCP, naming this as the top research theme in a recent Neurology ® publication. Precision therapeutics focuses on providing early effective interventions that are individualized to every patient and can guide research priorities to improve treatments for DCP. This commentary outlines current obstacles to improving treatment of DCP and addresses how precision therapeutics can address each of these obstacles through 4 key components: (1) identification of predictive biomarkers to select patients likely to develop DCP in the future and for whom early intervention may be appropriate to delay or prevent full manifestation of dystonia, (2) stratification of patients with DCP into subgroups according to shared features (clinical, functional, biochemical, etc) to provide a targeted intervention based on those shared features, (3) administration of an individualized dose of an effective intervention to ensure adequate concentrations of the therapeutic entity at the site of action, and (4) monitoring of objective biomarkers of response to intervention. With implementation of each of these components of precision therapeutics, new and more effective treatments for every person with DCP can be realized., (© 2023 American Academy of Neurology.)

Introduction: Movement disorders are the commonest clinical presentation in patients with neurological Wilson's disease (NWD). There are very few studies evaluating the spectrum, severity and their correlation with magnetic resonance imaging (MRI) changes of movement disorders in NWD., Objective: To study the spectrum, topographic distribution, radiological correlate, temporal course and outcome in our cohort of NWD patients., Methods: Retrospective chart review of the NWD patients having movement disorders was performed and analyzed., Results: Sixty-nine patients (males- 47) with NWD were analysed and the mean age at the onset of neurological symptoms was 13.6 ± 6.6 years (median 13 years; range 7-37 years). The first neurological symptom was movement disorder in 55 (79.7%) patients. Tremor (43.6%) and dystonia (41.8%) was the commonest movement disorder as the first neurological symptom. Dystonia (76.8%) was the most common overall movement disorder followed by parkinsonism (52.1%) and tremors (47.8%). Chorea (10.1%), myoclonus (1.4%) and ataxia (1.4%) were the least common movement disorder. Putamen was the most common affected site (95.6%) followed by caudate nucleus (73.9%), thalamus (60.8%), midbrain (59.4%), internal capsule (49.2%), pons (46.3%). Putamen was the most common area of abnormality in dystonia (98%), tremors (85%). Caudate (75%) and putamen (75%) was the most common areas of abnormality in parkinsonism. Favourable outcome was observed in 42 patients (60.8%) following treatment., Conclusion: Dystonia is the most common movement disorder in NWD in isolation or in combination with parkinsonism and tremors. Putamen is the most common radiological site of lesions and more frequently affected in patients with dystonia and tremors. Favourable outcome does occur with appropriate medical and surgical treatment., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2023 The Author(s).)

Patients with chronic psychosis on prolonged antipsychotic therapy may present with paroxysmal dystonia along with an exacerbation of their psychotic symptoms: paroxysmal dystonia and psychotic exacerbations (PDPE). The interindividual variability in the clinical presentations of PDPE can pose challenges in its diagnosis and treatment. The objectives of this work are to (i) discuss this rare phenomenon through a series of 10 patients and a relevant literature review, (ii) conceptualize its neurobiological underpinnings, and (iii) explore the preliminary treatment approaches for its management. Acute stress and/or a dysfunctional gamma-aminobutyric acid (GABA) ergic or dopaminergic system may be implicated in the pathogenesis of PDPE. The episodes respond acutely to parenteral benzodiazepines, while long-term management can be achieved by reducing antipsychotic doses, switching to clozapine or using central GABA enhancers. This article is the first attempt at conceptualizing and exploring treatment options for the rare condition PDPE and intends to guide future research in this regard., (© 2023 British Pharmacological Society.)

Objective: To evaluate the efficacy of CT-guided partial radiofrequency ablation of bilateral responsible cranial nerves in the treatment of Meige syndrome. Methods: The Clinical data of 56 patients with Meige syndrome in the Department of Pain Medicine, Affiliated Hospital of Jiaxing University from June 2019 to January 2023 were retrospectively analyzed [19 males and 37 females, aged 42-76 (58.6±8.3) years], including 51 cases of blepharospasm, 3 cases of oromandibular dystonia and 2 cases of blepharospasm concomitant with oromandibular dystonia. CT-guided partial radiofrequency ablation of bilateral responsible cranial nerves was performed on different types of Meige syndrome. And the efficacy and complications of the technique were observed. Results: Fifty-one patients with blepharospasm Meige syndrome underwent CT-guided radiofrequency of facial nerve through bilateral stylomastoid foramen punctures, the symptoms of blepharospasm disappeared completely, leaving bilateral mild and moderate facial paralysis symptoms. Three patients with oral-mandibular dystonia underwent CT-guided radiofrequency therapy by bilateral foramen ovale puncture of mandibular branches of trigeminal nerve, masticatory muscle spasm disappeared, the patients had no difficulty opening the mouth, and the skin numbness in bilateral mandibular nerve innervation area was left. Two cases of Meige syndrome with blepharospasm concomitant with oromandibular dystonia were treated by radiofrequency of facial nerve and mandibular branch of trigeminal nerve, and all symptoms disappeared. The patients were followed up for 1-44 months after the operation, and the symptoms of mild and moderate facial paralysis disappeared at (3.2±0.8) months after the operation, but the numbness did not disappear. Three patients with blepharospasm recurred at the 14, 18 and 22 months after the operation, respectively, while the rest cases did not recur. Conclusions: According to different types of Meige syndrome, CT-guided partial radiofrequency ablation of responsible cranial nerves can effectively treat the corresponding type of Meige syndrome. The complications are only mild and moderate facial paralysis which can be recovered, and/or skin numbness in the mandibular region.

Paroxysmal exercise-induced movement disorders may be caused by energy metabolism disorders, such as Glut 1 deficiency, pyruvate dehydrogenase deficiency, or mitochondrial respiratory chain disorders. A 4-year-old boy with a history of febrile seizures presented with paroxysmal dystonia, triggered by exercise, or occurring at rest. Additional investigations demonstrated pallidal hyperintensities on brain MRI and low CSF glucose. Pyruvate and lactate were elevated. The clinical presentation combined with neuroimaging abnormalities and biochemical profile (the lactate/pyruvate ratio) were clues to pyruvate dehydrogenase deficiency, a treatable metabolic disorder with neurologic presentations., (© 2023 American Academy of Neurology.)