Pharmacological and neurosurgical interventions for managing dystonia in cerebral palsy: a systematic review

Evidence for dystonia reduction in cerebral palsy remains limited

This commentary is on the clinical practice guideline by Fehlings et al. on pages 1133–1147 of this issue.

Efficacy of Oral Trihexyphenidyl Plus Clonazepam Versus Trihexyphenidyl for the Treatment of Dystonia in Children With Dystonic Cerebral Palsy: An Open-Label Randomized Controlled Trial

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.

Pharmacological and neurosurgical management of cerebral palsy and dystonia: Clinical practice guideline update

Dystonia, typically characterized by slow repetitive involuntary movements, stiff abnormal postures, and hypertonia, is common among individuals with cerebral palsy (CP). Dystonia can interfere with activities and have considerable impact on motor function, pain/comfort, and ease of caregiving. Although pharmacological and neurosurgical approaches are used clinically in individuals with CP and dystonia that is causing interference, evidence to support these options is limited. This clinical practice guideline update comprises 10 evidence-based recommendations on the use of pharmacological and neurosurgical interventions for individuals with CP and dystonia causing interference, developed by an international expert panel following the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. The recommendations are intended to help inform clinicians in their use of these management options for individuals with CP and dystonia, and to guide a shared decision-making process in selecting a management approach that is aligned with the individual's and the family's values and preferences.

AAPM&R consensus guidance on spasticity assessment and management

BACKGROUND

The American Academy of Physical Medicine and Rehabilitation (AAPM&R) conducted a comprehensive review in 2021 to identify opportunities for enhancing the care of adult and pediatric patients with spasticity. A technical expert panel (TEP) was convened to develop consensus-based practice recommendations aimed at addressing gaps in spasticity care.

OBJECTIVE

To develop consensus-based practice recommendations to identify and address gaps in spasticity care.

METHODS

The Spasticity TEP engaged in a 16-month virtual meeting process, focusing on formulating search terms, refining research questions, and conducting a structured evidence review. Evidence quality was assessed by the AAPM&R Evidence, Quality and Performance Committee (EQPC), and a modified Delphi process was employed to achieve consensus on recommendation statements and evidence grading. The Strength of Recommendation Taxonomy (SORT) guided the rating of individual studies and the strength of recommendations.

RESULTS

The TEP approved five recommendations for spasticity management and five best practices for assessment and management, with one recommendation unable to be graded due to evidence limitations. Best practices were defined as widely accepted components of care, while recommendations required structured evidence reviews and grading. The consensus guidance statement represents current best practices and evidence-based treatment options, intended for use by PM&R physicians caring for patients with spasticity.

CONCLUSION

This consensus guidance provides clinicians with practical recommendations for spasticity assessment and management based on the best available evidence and expert opinion. Clinical judgment should be exercised, and recommendations tailored to individual patient needs, preferences, and risk profiles. The accompanying table summarizes the best practice recommendations for spasticity assessment and management, reflecting principles with little controversy in care delivery.

Current approach to cerebral palsy

This teaching review aims to provide an overview of the current approach to children with cerebral palsy (CP), retrieving the best available evidence and summarizing existing knowledge in the field of CP in children. We also highlight areas where more research is needed and novel strategies for diagnosing and treating cerebral palsy. CP includes a group of permanent disorders of movement and posture that cause activity limitation. Multiple risk factors, occurring preconceptionally, prenatally, perinatally, or postneonatally, are involved in the pathogenesis of CP, with the prenatal ones accounting for 80-90 % of cases. Due to its heterogeneity, CP has various classifications, but usually is classified based on clinical findings and motor impairment. Standardized function classification systems have been developed to address inconsistencies in previous classifications. The combination of clinical assessment and validated predictive tools is recommended for an early diagnosis, which is important for early intervention and prevention of secondary impairments. The therapeutic regimen in CP involves prevention and management of the motor and associated problems. It includes the enhancement of motor performance, the enrichment of cognition and communication skills, the prevention of secondary impairments, and the support of parents and caregivers. The care of CP children demands a multidisciplinary approach focused on improving motor skills, reducing comorbidities, enhancing the quality of life, and prolonging survival.

A Systematic Review of Botulinum Toxin Injection in Pediatric Dystonia

Botulinum toxin (BT), a first-line treatment for focal dystonias in adults, has gained USA Food and Drug Administration approval for pediatric upper and lower extremity spasticity and sialorrhea, though its use in children younger than 2 years old is still considered off-label treatment for all pathologies. Dosing, treatment strategies and outcome measures lack international consensus, and they are often extrapolated from adult or spasticity guidelines. This review aims to evaluate the best available evidence on the efficacy and safety of BT therapy in pediatric dystonia (age under 21 years old), isolated or associated with other medical conditions. A comprehensive search in PubMed, Scopus and Web of Science was conducted, including only articles in English. Although no randomized controlled trials are still present, 12 articles were included with an overall of 57 patients. All the papers demonstrate that BT can improve motor function, decrease pain and ameliorate quality of life, with minimal adverse effects in pediatric patients affected by pure or mixed dystonic motor disorders. Despite the low level of evidence, our review shows that BT could be an efficacious treatment for these pediatric patients. The frequent generalized involvement, together with the heterogeneous nature of childhood dystonic forms, sometimes intermingled with spasticity, prompts further multicenter clinical trials or prospective studies with a higher level of evidence to shed light on the efficacy and safety profile of BT in pediatric dystonia.

Update in Pediatric Neurocritical Care: What a Neurologist Caring for Critically Ill Children Needs to Know

Currently nearly one-quarter of admissions to pediatric intensive care units (PICUs) worldwide are for neurocritical care diagnoses that are associated with significant morbidity and mortality. Pediatric neurocritical care is a rapidly evolving field with unique challenges due to not only age-related responses to primary neurologic insults and their treatments but also the rarity of pediatric neurocritical care conditions at any given institution. The structure of pediatric neurocritical care services therefore is most commonly a collaborative model where critical care medicine physicians coordinate care and are supported by a multidisciplinary team of pediatric subspecialists, including neurologists. While pediatric neurocritical care lies at the intersection between critical care and the neurosciences, this narrative review focuses on the most common clinical scenarios encountered by pediatric neurologists as consultants in the PICU and synthesizes the recent evidence, best practices, and ongoing research in these cases. We provide an in-depth review of (1) the evaluation and management of abnormal movements (seizures/status epilepticus and status dystonicus); (2) acute weakness and paralysis (focusing on pediatric stroke and select pediatric neuroimmune conditions); (3) neuromonitoring modalities using a pathophysiology-driven approach; (4) neuroprotective strategies for which there is evidence (e.g., pediatric severe traumatic brain injury, post-cardiac arrest care, and ischemic stroke and hemorrhagic stroke); and (5) best practices for neuroprognostication in pediatric traumatic brain injury, cardiac arrest, and disorders of consciousness, with highlights of the 2023 updates on Brain Death/Death by Neurological Criteria. Our review of the current state of pediatric neurocritical care from the viewpoint of what a pediatric neurologist in the PICU needs to know is intended to improve knowledge for providers at the bedside with the goal of better patient care and outcomes.

Fifteen-minute consultation: Management of acute dystonia exacerbation and status dystonicus

Dystonia is a common disorder of movement and tone, characterised by sustained or intermittent muscle contractions causing abnormal movements, postures or both. Children and young people with dystonia can experience episodes of acute worsening tone, which require prompt treatment. When most severe, dystonia may become life-threatening-a state called 'status dystonicus'. This guide aims to provide a framework for how to approach the child with acutely worsening dystonia, following an 'ABCD' approach: Addressing the precipitant, Beginning supportive care, Calibrating sedation and Dystonia-specific medications.

Recommendations for the Management of Initial and Refractory Pediatric Status Dystonicus

Status dystonicus is the most severe form of dystonia with life-threatening complications if not treated promptly. We present consensus recommendations for the initial management of acutely worsening dystonia (including pre-status dystonicus and status dystonicus), as well as refractory status dystonicus in children. This guideline provides a stepwise approach to assessment, triage, interdisciplinary treatment, and monitoring of status dystonicus. The clinical pathways aim to: (1) facilitate timely recognition/triage of worsening dystonia, (2) standardize supportive and dystonia-directed therapies, (3) provide structure for interdisciplinary cooperation, (4) integrate advances in genomics and neuromodulation, (5) enable multicenter quality improvement and research, and (6) improve outcomes. © 2024 International Parkinson and Movement Disorder Society.

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.

Clinical and Psychosocial Factors Considered When Deciding Whether to Offer Deep Brain Stimulation for Childhood Dystonia

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.

Identifying Effective Treatments for Dystonia in Patients With Cerebral Palsy: A Precision Therapeutics Approach

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.

Neurosurgical management of elevated tone in childhood: interventions, indications and uncertainties

Elevated tone (hypertonia) is a common problem in children with physical disabilities. Medications intended to reduce tone often have limited efficacy, with use further limited by a significant side effect profile. Consequently, there has been growing interest in the application of Neurosurgical Interventions for the Management of Posture and Tone (NIMPTs). Three main procedures are now commonly used: selective dorsal rhizotomy (SDR), intrathecal baclofen (ITB) and deep brain stimulation (DBS). This review compares these interventions, along with discussion on the potential role of lesioning surgery. These interventions variably target spasticity and dystonia, acting at different points in the distributed motor network. SDR, an intervention for reducing spasticity, is most widely used in carefully selected ambulant children with cerebral palsy. ITB is more commonly used for children with more severe disability, typically non-ambulant, and can improve both dystonia and spasticity. DBS is an intervention which may improve dystonia. In children with certain forms of genetic dystonia DBS may dramatically improve dystonia. For other causes of dystonia, and in particular dystonia due to acquired brain injury, improvements following surgery are more modest and variable. These three interventions vary in terms of their side-effect profile and reversibility. There are currently populations of children for who it is unclear which intervention should be considered (SDR vs ITB, or ITB vs DBS). Concerns have been raised as to the equity of access to NIMPTs for children across the UK, and whether the number of surgeries performed each year meets the clinical need.

Bilateral globus pallidus interna deep brain stimulation in the treatment of mixed cerebral palsy in ataxia with dyskinesia: a case report

Background

Cerebral palsy (CP), a complex syndrome with multiple etiologies, is characterized by a range of movement disorders within the hypokinetic and hyperkinetic spectrum (dystonia or choreoathetosis). CP is often accompanied by neurological and psychiatric signs, such as spasticity, ataxia, and cognitive disorders. Although current treatment options for CP include pharmacological interventions, rehabilitation programs, and spasticity relief surgery, their effectiveness remains limited. Deep brain stimulation (DBS) has demonstrated significant effectiveness in managing dyskinesia; however, its potential therapeutic effect on CP remains determined.

Methods

We present a case of a 44-year-old Asian female who was born as a twin with neonatal ischemic-hypoxic encephalopathy due to prolonged labor and delivery. She was diagnosed with CP at the age of 1 year. The patient exhibited delayed development compared to her peers and presented with various symptoms, including slurred speech, broad-based gait, horseshoe inversion of the right lower extremity, involuntary shaking of the upper extremities bilaterally, and hypotonia and showed no improvement with levodopa therapy. Two years ago, she developed progressive head tremors, which worsened during periods of tension and improved during sleep. As medical treatments proved ineffective and there were no contraindications to surgery, we performed bilateral globus pallidus interna DBS (GPi-DBS) to alleviate her motor dysfunction.

Results

Following a 6-month follow-up, the patient demonstrated significant improvements in motor symptoms, including head and limb tremors and dystonia. In addition, significant improvement was observed in her overall psychological well-being, as evidenced by reduced anxiety and depression levels.

Conclusion

DBS is an effective treatment for dyskinesia symptoms associated with CP in adults. Moreover, its effectiveness may continue to increase over time.

Metabolic patterns in brain 18F-fluorodeoxyglucose PET relate to aetiology in paediatric dystonia

There is a lack of imaging markers revealing the functional characteristics of different brain regions in paediatric dystonia. In this observational study, we assessed the utility of [18F]2-fluoro-2-deoxy-D-glucose (FDG)-PET in understanding dystonia pathophysiology by revealing specific resting awake brain glucose metabolism patterns in different childhood dystonia subgroups. PET scans from 267 children with dystonia being evaluated for possible deep brain stimulation surgery between September 2007 and February 2018 at Evelina London Children's Hospital (ELCH), UK, were examined. Scans without gross anatomical abnormality (e.g. large cysts, significant ventriculomegaly; n = 240) were analysed with Statistical Parametric Mapping (SPM12). Glucose metabolism patterns were examined in the 144/240 (60%) cases with the 10 commonest childhood-onset dystonias, focusing on nine anatomical regions. A group of 39 adult controls was used for comparisons. The genetic dystonias were associated with the following genes: TOR1A, THAP1, SGCE, KMT2B, HPRT1 (Lesch Nyhan disease), PANK2 and GCDH (Glutaric Aciduria type 1). The acquired cerebral palsy (CP) cases were divided into those related to prematurity (CP-Preterm), neonatal jaundice/kernicterus (CP-Kernicterus) and hypoxic-ischaemic encephalopathy (CP-Term). Each dystonia subgroup had distinct patterns of altered FDG-PET uptake. Focal glucose hypometabolism of the pallidi, putamina or both, was the commonest finding, except in PANK2, where basal ganglia metabolism appeared normal. HPRT1 uniquely showed glucose hypometabolism across all nine cerebral regions. Temporal lobe glucose hypometabolism was found in KMT2B, HPRT1 and CP-Kernicterus. Frontal lobe hypometabolism was found in SGCE, HPRT1 and PANK2. Thalamic and brainstem hypometabolism were seen only in HPRT1, CP-Preterm and CP-term dystonia cases. The combination of frontal and parietal lobe hypermetabolism was uniquely found in CP-term cases. PANK2 cases showed a distinct combination of parietal hypermetabolism with cerebellar hypometabolism but intact putaminal-pallidal glucose metabolism. HPRT1, PANK2, CP-kernicterus and CP-preterm cases had cerebellar and insula glucose hypometabolism as well as parietal glucose hypermetabolism. The study findings offer insights into the pathophysiology of dystonia and support the network theory for dystonia pathogenesis. 'Signature' patterns for each dystonia subgroup could be a useful biomarker to guide differential diagnosis and inform personalized management strategies.

A Technique of Deep Brain Stimulation of the Globus Pallidus Interna for Dystonia Under General Anesthesia With Sevoflurane

Background Globus pallidus interna (GPi) deep brain stimulation (DBS) is an established surgical procedure that confers a benefit in medication refractory dystonia. Patients with generalized dystonia require general anesthesia (GA) for the surgery as their movements may hinder the surgical procedure. General anesthetics tend to dampen the microelectrode recordings (MERs) from the GPi. Methods We describe our experience with a series of consecutive patients with dystonia who underwent bilateral GPi DBS using standard DBS and MER under GA using sevoflurane as the maintenance general anesthetic drug. All patients had Medtronic 3,387 leads implanted and connected to an RC battery. Patients underwent sequential programming of the DBS after the surgery. Results The mean age of the 13 patients who underwent DBS of the GPi for dystonia was 46.5 years with a range from 29 to 71 years. Every patient in our case series received various doses of (1.37% to 2.11%) inhaled sevoflurane for anesthesia maintenance. Sevoflurane provided adequate anesthesia and allowed accurate MERs from the GPi. No adverse effects were encountered. On follow-up and sequential DBS programming, patients had significant improvements in dystonia attesting to the accuracy of the electrode placements. Conclusions We report our experience using sevoflurane for maintenance of GA for bilateral GPi DBS for dystonia. The main benefits identified have been adequate anesthesia and reduction of dystonia-related movements to allow the performance of the DBS surgery. The MER signals from the GPi were not suppressed by sevoflurane. This allowed accurate mapping and placement of the DBS implants in the GPi.

Attainment of personal goals in the first year of intrathecal baclofen treatment in dyskinetic cerebral palsy: a prospective cohort study

PURPOSE

To assess attainment of individual treatment goals one year after intrathecal baclofen (ITB) pump implantation in individuals with dyskinetic cerebral palsy (CP).

MATERIALS AND METHODS

A multi-center prospective cohort study was conducted including 34 non-walking individuals with severe dyskinetic CP, classified as Gross Motor Function Classification System (GMFCS) IV/V, aged 4-24 years, 12 months after pump implantation. The main outcome measure was Goal Attainment Scaling (GAS). Predictors of GAS results were analyzed. Complications were registered systematically.

RESULTS

Seventy-one percent of individuals with dyskinetic CP fully achieved one or more treatment goals. One or more treatment goals were partially achieved in 97% of individuals. Two factors were found to be associated with attainment of goals: Dyskinesia Impairment Scale (DIS) score at baseline and the difference in pain score between baseline and follow-up. These two variables explain 30% of the variance in the outcome.

CONCLUSIONS

Intrathecal baclofen is effective in achieving individual treatment goals in children and young adults with dyskinetic CP after nine to 12 months of ITB treatment. A positive outcome on treatment goals is, for a small part, associated with higher severity of dystonia at baseline and with improvement of pain during treatment.

CLINICAL TRIAL REGISTRATION NUMBER

Dutch Trial Register, number NTR3642.Implications for rehabilitationIntrathecal baclofen treatment is effective in attainment of personal treatment goals, one year after pump implantation in patients with dyskinetic cerebral palsy.A positive outcome on treatment goals is, for a small part, related to higher severity of dystonia at the start and on improvement of pain during treatment.

Providing a Primary Care Medical Home for Children and Youth With Cerebral Palsy

Cerebral palsy (CP) is the most common motor disorder of childhood, with prevalence estimates ranging from 1.5 to 4 in 1000 live births. This clinical report seeks to provide primary care physicians with guidance to detect children with CP; collaborate with specialists in treating the patient; manage associated medical, developmental, and behavioral problems; and provide general medical care to their patients with CP.

Trihexyphenidyl in young children with dystonic cerebral palsy: A single arm study

PURPOSE

The incidence of dystonic cerebral palsy causing significant morbidity is on the rise. There is a paucity of evidence for the management of dystonia in children.

METHODS

Forty-one children aged 6 months-5 years with predominantly dystonic cerebral palsy were started on a predetermined protocol of trihexyphenidyl (0.25-0.52 mg/kg) and followed up at 3, 6 and 12 weeks. Dystonia severity, motor function and developmental age at baseline and 12 weeks were compared using the Global Dystonia Scale (GDS), the Gross Motor Function Measure (GMFM), and Fine Motor/Perceptual Subscale of the Early Developmental Profile-2. Thirty-four children completed the entire 12 weeks of intervention.

RESULTS

The mean age of participants was 25±11 months. A significant decrease in median total dystonia scores on the GDS was observed post-intervention (74.5 to 59, p <  0.0001), and 64% of participants gained motor milestones. GMFM scores increased significantly from a median of 19.8% pre-intervention to 26.5% post-intervention (p <  0.0001). There was improvement in the fine motor domain as compared to the baseline (p <  0.0001). The number of children classified at Gross Motor Function Classification System levels 1 and 2 increased to 47.05% from 5.88% in the pre-intervention group.

CONCLUSION

Trihexyphenidyl significantly improved dystonia, motor function and development in children with dystonic cerebral palsy in this study. Additional studies are needed to clarify its role in larger numbers of children with this condition.

Psychosocial and medical factors associated with intrathecal baclofen pump explants: A case series

PURPOSE

The goal of this retrospective chart review study was to explore factors that contributed to consideration of or actual pump explantation in pediatric patients with intrathecal baclofen (ITB) pumps.

METHODS

Medical records of 30 patients with ITB pumps were reviewed. Quantitative data, including demographic, clinical, psychosocial, and service utilization variables were culled from the records. Qualitative data were collected from clinic visit notes, pump-related follow-up phone calls, and any pump-related emergency room visits.

RESULTS

Of those reviewed, six underwent ITB pump explantation, and two considered explantation. Factors contributing to pump explantation or consideration of explantation included the following: postoperative infection, pump malfunction, non-adherence, anxiety/behavioral factors impacting the patient's tolerance of the pump, distance to the medical provider, frequency of required pump refill appointments, lack or perceived lack of intrathecal baclofen effect, and difficulty transitioning to adult care providers.

CONCLUSION

Due to the complex care regimen associated with ITB pumps and various psychosocial and logistical factors that impact treatment success, a standardized multidisciplinary pre-implantation education, screening, and assessment process should be developed. Such a process would ensure that patients/families receive appropriate education, including proactively identifying treatment barriers and potential complications, possibly minimizing dissatisfaction with treatment and the need for explantation.

Dystonia in children with acquired brain injury

AIM

To quantify the proportion of children who develop dystonia after acquired brain injury (ABI) admitted to a tertiary paediatric intensive care unit (PICU) and analyse the trajectory of dystonia over a 6 month period.

METHODS

Children's Health Ireland at Temple Street PICU electronic database was searched for key terms related to ABI from January 1, 2016 to March 14, 2021. Individuals meeting inclusion criteria were analysed, and clinical data pertinent to ABI, dystonia, treatment and outcomes were reviewed.

RESULTS

Six-hundred and forty-three PICU episodes (580 patients) met search criteria for ABI, with 379 included in the final analysis. Twelve patients developed dystonia following ABI, giving an incidence of 3.2%. The incidence was higher in the hypoxia/anoxia and TBI cohort at 8.3% and 6.2%, respectively. All patients developed dystonia within the first month following ABI (50% by a week). Patients who developed dystonia compared to non-dystonia cohort had a median lower GCS on admission (4.5 versus 7.0, p value 0.032), longer median length of PICU stay (14.0 versus 3.0 days, p value < 0.001) and were older (median age 9.08 versus 4.68 years, p value 0.06). Dystonia persisted in the majority at 6 months (10/11), requiring on-going medical therapies.

CONCLUSION

In our retrospective study, the estimated incidence of dystonia following ABI admitted to the PICU was 3.2%, highest in the hypoxia/anoxia (8.3%) and TBI (6.2%) cohorts. Dystonia emerged early and persisted at 6 months in the majority. This is the first review of dystonia, clinical trajectory and outcomes conducted post-PICU admission for ABI. Future prospective studies are required to determine the true prevalence and burden of disease in the PICU setting.

Harnessing cognitive strategy use for functional problems and proposed underlying mechanisms in childhood-onset dystonia

BACKGROUND

There is a significant gap in knowledge about rehabilitation techniques and strategies that can help children and young people with hyperkinetic movement disorders (HMD) including dystonia to successfully perform daily activities and improve overall participation. A promising approach to support skill acquisition is the Cognitive Orientation to daily Occupational Performance (CO-OP) intervention. CO-OP uses cognitive strategies to help patients generate their own solutions to overcome self-identified problems encountered in everyday living.

PURPOSE

1. To identify and categorize strategies used by children with HMD to support skill acquisition during CO-OP; 2. To review the possible underlying mechanisms that might contribute to the cognitive strategies, in order to facilitate further studies for developing focused rehabilitation approaches.

METHODS

A secondary analysis was performed on video-recorded data from a previous study exploring the efficacy of CO-OP for childhood onset HMD, in which CO-OP therapy sessions were delivered by a single occupational therapist. For the purpose of this study, we reviewed a total of 40 randomly selected hours of video footage of CO-OP sessions delivered to six participants (age 6-19 years) over ten intervention sessions. An observational recording sheet was applied to identify systematically the participants' or therapist's verbalizations of cognitive strategies during the therapy. The strategies were classified into six categories in line with published literature.

RESULTS

Strategies used by HMD participants included distraction, externally focussed attention, internally focussed attention, emotion self-regulation, motor imagery and mental self-guidance. We postulate different underlying working mechanisms for these strategies, which have implications for the therapeutic management of children and young people with HMD including dystonia.

CONCLUSIONS

Cognitive strategy training can fundamentally change and improve motor performance. On-going work will address both the underlying neural mechanisms of therapeutic change and the mediators and moderators that influence how change unfolds.

Recommendations for diagnosing and managing individuals with glutaric aciduria type 1: Third revision

Glutaric aciduria type 1 is a rare inherited neurometabolic disorder of lysine metabolism caused by pathogenic gene variations in GCDH (cytogenic location: 19p13.13), resulting in deficiency of mitochondrial glutaryl-CoA dehydrogenase (GCDH) and, consequently, accumulation of glutaric acid, 3-hydroxyglutaric acid, glutaconic acid and glutarylcarnitine detectable by gas chromatography/mass spectrometry (organic acids) and tandem mass spectrometry (acylcarnitines). Depending on residual GCDH activity, biochemical high and low excreting phenotypes have been defined. Most untreated individuals present with acute onset of striatal damage before age 3 (to 6) years, precipitated by infectious diseases, fever or surgery, resulting in irreversible, mostly dystonic movement disorder with limited life expectancy. In some patients, striatal damage develops insidiously. In recent years, the clinical phenotype has been extended by the finding of extrastriatal abnormalities and cognitive dysfunction, preferably in the high excreter group, as well as chronic kidney failure. Newborn screening is the prerequisite for pre-symptomatic start of metabolic treatment with low lysine diet, carnitine supplementation and intensified emergency treatment during catabolic episodes, which, in combination, have substantially improved neurologic outcome. In contrast, start of treatment after onset of symptoms cannot reverse existing motor dysfunction caused by striatal damage. Dietary treatment can be relaxed after the vulnerable period for striatal damage, that is, age 6 years. However, impact of dietary relaxation on long-term outcomes is still unclear. This third revision of evidence-based recommendations aims to re-evaluate previous recommendations (Boy et al., J Inherit Metab Dis, 2017;40(1):75-101; Kolker et al., J Inherit Metab Dis 2011;34(3):677-694; Kolker et al., J Inherit Metab Dis, 2007;30(1):5-22) and to implement new research findings on the evolving phenotypic diversity as well as the impact of non-interventional variables and treatment quality on clinical outcomes.

Deep Brain Stimulation for Pediatric Dystonia: A Review of the Literature and Suggested Programming Algorithm

Deep brain stimulation (DBS) is an established intervention for use in pediatric movement disorders, especially dystonia. Although multiple publications have provided guidelines for deep brain stimulation patient selection and programming in adults, there are no evidence-based or consensus statements published for pediatrics. The result is lack of standardized care and underutilization of this effective treatment. To this end, we assembled a focus group of 13 pediatric movement disorder specialists and 1 neurosurgeon experienced in pediatric deep brain stimulation to review recent literature and current practices and propose a standardized approach to candidate selection, implantation target site selection, and programming algorithms. For pediatric dystonia, we provide algorithms for (1) programming for initial session and follow-up sessions, and (2) troubleshooting side effects encountered during programming. We discuss common side effects, how they present, and recommendations for management. This topical review serves as a resource for movement disorders specialists interested in using deep brain stimulation for pediatric dystonia.

Management of severe spasticity with and without dystonia with intrathecal baclofen in the pediatric population: a cross-sectional study

Objective

To investigate the differences in delivery mode, daily dose, and catheter tip location in pediatric patients using intrathecal baclofen (ITB) pumps with spasticity plus dystonia versus spasticity alone.

Methods

A single-center, cross-sectional study was performed by collecting retrospective data from electronic medical records. Demographic and diagnostic information was obtained, comparing patients with spasticity with or without dystonia. The data were analyzed for group differences using a two-tailed Student’s t-test. Categorical data were analyzed for group differences using Pearson’s χ2 test.

Results

A total of 137 patients met the criteria. The majority (114) had spasticity plus dystonia whereas only 23 were documented as spasticity alone. Simple continuous dosing was the most common delivery mode, but flex dosing was used more than twice as frequently with spasticity plus dystonia compared with spasticity alone (42% vs 17%). Patients with spasticity plus dystonia also had more rostral catheter tip locations.

Conclusions

While it has been discussed anecdotally, this study confirms the supposition that patients with spasticity plus dystonia have increased dose requirements when compared with those with spasticity alone. Although there are no clear standards of care when managing these patients, they are often on higher daily dosages, are more likely to require flexed dosing method, and have higher catheter placements. Still, there are few studies that demonstrate improvements in dystonia with the use of ITB. In general, these patients would benefit from the development of universal standardizations as well as the confirmation that this is an appropriate treatment.

Effect of targeted movement interventions on pain and quality of life in children with dyskinetic cerebral palsy: a pilot single subject research design to test feasibility of parent-reported assessments

PURPOSE

To determine the feasibility of using parent-reported outcome measures of the Paediatric Pain Profile (PPP), Sleep Disturbance Scale for Children (SDSC) and Care and Comfort Hypertonicity Questionnaire (CCHQ) as repeated outcome measures of change at weekly intervals for children with dyskinetic cerebral palsy (CP). The secondary aim was to explore the efficacy of individualised movement intervention.

MATERIAL AND METHODS

In this pilot feasibility study a single subject research design was utilised. Three children with dyskinetic CP, completed 5 weeks of parent-reported baseline assessments, 8 weekly sessions of intervention and 5 weeks of follow up.

RESULTS

All children completed 18 weeks of the study, with no missing data. There was evidence of parent-reported improvements in their child's pain and care and comfort between the baseline and intervention phases.

CONCLUSIONS

The PPP, SDSC and CCHQ were feasible to assess pain, sleep and comfort before and after an intervention in children with dyskinetic CP. There is preliminary evidence that individualised movement intervention as little as once a week may help improve pain, sleep and improve ease of care and comfort. IMPLICATIONS FOR REHABILITATIONThe Paediatric Pain Profile is feasible to identify and monitor pain, as frequently as weekly, in children with dyskinetic cerebral palsy (CP).There is preliminary evidence that movement can decrease pain in children with dyskinetic CP.Assessments and treatment in this group may be interrupted due to their complex health issues which may be a limitation when collecting repeated measures.

Movement disorders in patients with Rett syndrome: A systematic review of evidence and associated clinical considerations

AIM

This systematic review identified and thematically appraised clinical evidence of movement disorders in patients with Rett syndrome (RTT).

METHOD

Using PRISMA criteria, six electronic databases were searched from inception to April 2021. A thematic analysis was then undertaken on the extracted data to identify potential themes.

RESULTS

Following the thematic analysis, six themes emerged: (i) clinical features of abnormal movement behaviors; (ii) mutational profile and its impact on movement disorders; (iii) symptoms and stressors that impact on movement disorders; (iv) possible underlying neurobiological mechanisms; (v) quality of life and movement disorders; and (vi) treatment of movement disorders. Current guidelines for managing movement disorders in general were then reviewed to provide possible treatment recommendations for RTT.

CONCLUSION

Our study offers an enriched data set for clinical investigations and treatment of fine and gross motor issues in RTT. A detailed understanding of genotype-phenotype relationships of movement disorders allows for more robust genetic counseling for families but can also assist healthcare professionals in terms of monitoring disease progression in RTT. The synthesis also showed that environmental enrichment would be beneficial for improving some aspects of movement disorders. The cerebellum, basal ganglia, alongside dysregulation of the cortico-basal ganglia-thalamo-cortical loop, are likely anatomical targets. A review of treatments for movement disorders also helped to provide recommendations for treating and managing movement disorders in patients with RTT.

Intrathecal baclofen pumps in the management of hypertonia in childhood: a UK and Ireland wide survey

BACKGROUND

Intrathecal baclofen (ITB) is a useful treatment for hypertonia where non-invasive treatments have been ineffective or poorly tolerated. There is an absence of national guidance on selection criteria and a lack of literature regarding patient characteristics and treatment details for children and young people (CYP) receiving ITB therapy in the UK and Ireland. We aimed to gather patient and treatment characteristics for CYP receiving ITB in the UK and Ireland.

METHODS

An electronic survey was sent to all paediatric ITB centres in the UK and Ireland. Anonymised data were returned between December 2019 and April 2020. CYP >16 years and those awaiting ITB pump removal were excluded from the dataset.

RESULTS

176 CYP were identified as receiving ITB therapy across the UK and Ireland. The majority of CYP with ITB pumps were non-ambulant (93%) with a diagnosis of cerebral palsy (79%). Median age of ITB insertion was 9 years; median current age was 14 years. 79% of CYP had significant spasticity, 55% had significant dystonia. The most commonly used ITB dosing modes were continuous (73%) and flexible (23%).

CONCLUSIONS

ITB pumps were most frequently used for non-ambulant CYP with cerebral palsy and existence of spasticity and/or dystonia in the UK and Ireland. Most CYP were receiving a continuous dose of ITB. There is significant variation in the number of paediatric ITB pumps across UK and Ireland. There is a need for development of nationally accepted paediatric referral criteria and clinical standards for ITB use.

Pharmacological and neurosurgical interventions for individuals with cerebral palsy and dystonia: a systematic review update and meta-analysis

AIM

To update a systematic review of evidence published up to December 2015 for pharmacological/neurosurgical interventions among individuals with cerebral palsy (CP) and dystonia.

METHOD

Searches were updated (January 2016 to May 2020) for oral baclofen, trihexyphenidyl, benzodiazepines, clonidine, gabapentin, levodopa, botulinum neurotoxin (BoNT), intrathecal baclofen (ITB), and deep brain stimulation (DBS), and from database inception for medical cannabis. Eligible studies included at least five individuals with CP and dystonia and reported on dystonia, goal achievement, motor function, pain/comfort, ease of caregiving, quality of life (QoL), or adverse events. Evidence certainty was evaluated using GRADE.

RESULTS

Nineteen new studies met inclusion criteria (two trihexyphenidyl, one clonidine, two BoNT, nine ITB, six DBS), giving a total of 46 studies (four randomized, 42 non-randomized) comprising 915 participants when combined with those from the original systematic review. Very low certainty evidence supported improved dystonia (clonidine, ITB, DBS) and goal achievement (clonidine, BoNT, ITB, DBS). Low to very low certainty evidence supported improved motor function (DBS), pain/comfort (clonidine, BoNT, ITB, DBS), ease of caregiving (clonidine, BoNT, ITB), and QoL (ITB, DBS). Trihexyphenidyl, clonidine, BoNT, ITB, and DBS may increase adverse events. No studies were identified for benzodiazepines, gabapentin, oral baclofen, and medical cannabis.

INTERPRETATION

Evidence evaluating the use of pharmacological and neurosurgical management options for individuals with CP and dystonia is limited to between low and very low certainty. What this paper adds Meta-analysis suggests that intrathecal baclofen (ITB) and deep brain stimulation (DBS) may improve dystonia and pain. Meta-analysis suggests that DBS may improve motor function. Clonidine, botulinum neurotoxin, ITB, and DBS may improve achievement of individualized goals. ITB and DBS may improve quality of life. No direct evidence is available for oral baclofen, benzodiazepines, gabapentin, or medical cannabis.

Musculoskeletal and skin considerations in children with medical complexity: Common themes and approaches to management

The term "children with medical complexity" (CMC) describes a population of heterogeneous genetic and metabolic disorders with multi-system involvement, with shared common abnormalities within the musculoskeletal system. Disorders that affect the central nervous system (CNS) result in abnormal muscular tone, ranging from dystonia and spasticity, to hypotonia, to combinations of both (axial hypotonia with appendicular hypertonia). Abnormal tone can impair movement and function and contribute to development of contractures, progressive scoliosis and hip dislocation. Impaired mobility, chronic illness and polypharmacy can result in fragile bones and increased risk of fracture, which can be difficult to diagnose and associated with pain. Additionally, CMC with impaired ability to communicate, total dependence on caregivers and frequent use of support devices can develop unintended skin injuries. There are a variety of treatments available for CMC with musculoskeletal disorders ranging from physical supports to pharmacologic treatments to surgeries. Medical and surgical treatments can promote changes in tone and support bone health to improve comfort, hygiene and proper positioning. These therapies may also carry significant risk in medically fragile patients. It is important for CMC to have a care team with a good understanding of the patient's overall health and goals of care and that can advocate for the patient to balance optimization of function and reduction of pain while also minimizing risk.

A pilot feasibility study of gabapentin for managing pain in children with dystonic cerebral palsy

BACKGROUND

Gabapentin is often used to manage pain in children with dystonic cerebral palsy, however the evidence for its effectiveness in this population is limited. The primary objective of this feasibility pilot study was to assess the factors which might impact on a future randomised controlled trial including the ability to recruit and retain participants, assess adherence/compliance to the prescribed intervention, and ability to complete all outcome assessments. The secondary objective was to gather preliminary evidence for the effectiveness of gabapentin at reducing pain, improving comfort and reducing dystonia in children with dystonic cerebral palsy.

METHODS

This open label pilot study recruited children aged 5-18 years with dystonic cerebral palsy and accompanying pain affecting daily activities from four centres around Australia. Children were prescribed gabapentin for 12 weeks and were assessed at baseline, 6 weeks and 12 weeks. The primary outcome was feasibility of the protocol. Secondary outcomes were pain behaviour, pain intensity, care and comfort, individualised goal setting and dystonia severity.

RESULTS

Thirteen children (mean age 10.4 years (SD 2.4yrs), 9 females) were recruited from 71 screened over 15 months. Two children withdrew while eight children experienced side effects. There were issues with adherence to medication dosage regimens and data collection. Improvements were seen in pain behaviour, comfort and pain related goals at 12 weeks. Dystonia was not significantly changed.

CONCLUSIONS

Whilst gabapentin has potential to improve pain and comfort in children with dystonic CP, the feasibility of implementing a definitive randomised controlled trial is low. Alternative trials designs are required to further examine the effectiveness of gabapentin in this heterogeneous population.

TRIAL REGISTRATION

The trial was registered with the Australian Clinical Trial Registry ( ACTRN12616000366459 ) on 22/03/2016 and the Therapeutic Goods Administration (CT-2016-CTN-00500-1) on 22/06/2016.

Multi-Organ Dysfunction in Cerebral Palsy

Cerebral Palsy (CP) describes a heterogenous group of non-progressive disorders of posture or movement, causing activity limitation, due to a lesion in the developing brain. CP is an umbrella term for a heterogenous condition and is, therefore, descriptive rather than a diagnosis. Each case requires detailed consideration of etiology. Our understanding of the underlying cause of CP has developed significantly, with areas such as inflammation, epigenetics and genetic susceptibility to subsequent insults providing new insights. Alongside this, there has been increasing recognition of the multi-organ dysfunction (MOD) associated with CP, in particular in children with higher levels of motor impairment. Therefore, CP should not be seen as an unchanging disorder caused by a solitary insult but rather, as a condition which evolves over time. Assessment of multi-organ function may help to prevent complications in later childhood or adulthood. It may also contribute to an improved understanding of the etiology and thus may have an implication in prevention, interventional methods and therapies. MOD in CP has not yet been quantified and a scoring system may prove useful in allowing advanced clinical planning and follow-up of children with CP. Additionally, several biomarkers hold promise in assisting with long-term monitoring. Clinicians should be aware of the multi-system complications that are associated with CP and which may present significant diagnostic challenges given that many children with CP communicate non-verbally. A step-wise, logical, multi-system approach is required to ensure that the best care is provided to these children. This review summarizes multi-organ dysfunction in children with CP whilst highlighting emerging research and gaps in our knowledge. We identify some potential organ-specific biomarkers which may prove useful in developing guidelines for follow-up and management of these children throughout their lifespan.

National surveillance of oral medication prescription for children with dystonic cerebral palsy

AIM

Oral medications are often first-line medical management for children with cerebral palsy who have generalised dystonia; however, evidence for their effectiveness is limited and dosing practices are inconsistent. As a first step to improve consistency, this study aimed to examine current clinical practice of expert doctors for prescribing medications for children with dystonic cerebral palsy including prescribing patterns and combinations of medications used.

METHODS

This was a prospective surveillance study of medical doctors working in major Australian centres who manage children with cerebral palsy. Each week over a continuous 6-month period, doctors completed a custom developed online survey for children seen that week with dystonic cerebral palsy for whom they prescribed a new medication to treat dystonia.

RESULTS

Twenty-five doctors consented to participate, 16 of whom prescribed new medications for dystonia in children with cerebral palsy over the study period. There were 77 children who were prescribed new medications. Baclofen and gabapentin were prescribed most, followed by levodopa, trihexyphenidyl and diazepam. The most common combinations of medications were baclofen and diazepam or baclofen and gabapentin. Dosage regimens were variable, particularly for trihexyphenidyl and diazepam.

CONCLUSION

Inconsistencies in dosing regimens remain for oral medication prescription by Australian doctors when managing dystonia in cerebral palsy. Future studies using the consensus of expert clinicians will be conducted to develop guidelines in an area where the evidence for individual medications is extremely limited.

Efficacy of axial TheraTogs on gait pattern in children with dyskinetic cerebral palsy: a randomized controlled trial

Background

TheraTogs promotes proprioceptive sense of a child with cerebral palsy and improves abnormal muscle tone, posture alignment, balance, and gait. Therefore, the aim of this study was to investigate the efficacy of TheraTogs orthotic undergarment on gait pattern in children with dyskinetic cerebral palsy. Thirty children with dyskinetic cerebral palsy were selected for this randomized controlled study. They were randomly assigned to (1) an experimental group that received TheraTogs orthotic undergarment (12 h/day, 3 days/week) plus traditional physical therapy for 3 successive months and (2) a control group that received only traditional physical therapy program for the same time period. Gait parameters were measured at baseline and after 3 months of intervention using Pro-Reflex motion analysis.

Results

Children in both groups showed significant improvements in the gait parameters (P < 0.05), with significantly greater improvements in the experimental group than in the control group.

Conclusions

The use of TheraTogs may have a positive effect to improve gait pattern in children with dyskinetic cerebral palsy.

Trial registration

This trial was registered in the ClinicalTrial.gov PRS (NCT03037697).

Deep Brain Stimulation and Hypoxemic Perinatal Encephalopathy: State of Art and Perspectives

Cerebral palsy (CP) is a heterogeneous group of non-progressive syndromes with lots of clinical variations due to the extent of brain damages and etiologies. CP is majorly defined by dystonia and spasticity. The treatment of acquired dystonia in CP is very difficult. Many pharmacological treatments have been tried and surgical treatment consists of deep brain stimulation (continuous electrical neuromodulation) of internal globus pallidus (GPi). A peculiar cause of CP is neonatal encephalopathy due to an anoxic event in the perinatal period. Many studies showed an improvement of dystonia in CP patients with bilateral GPi DBS. However, it remains a variability in the range of 1% to 50%. Published case-series concerned mainly small population with a majority of adult patients. Selection of patients according to the clinical pattern, to the brain lesions observed on classical imaging and to DTI is the key of a high success rate of DBS in children with perinatal hypoxemic encephalopathy. Only a large retrospective study with a high number of patients in a homogeneous pediatric population with a long-term follow-up or a prospective multicenter trial investigation could answer with a high degree of certitude of the real interest of this therapeutic in children with hypoxemic perinatal encephalopathy.

Objective and Clinically Feasible Analysis of Diffusion MRI Data can Help Predict Dystonia After Neonatal Brain Injury

BACKGROUND

Dystonia in cerebral palsy is debilitating but underdiagnosed precluding targeted treatment that is most effective if instituted early. Deep gray matter injury is associated with dystonic cerebral palsy but is difficult to quantify. Objective and clinically feasible identification of injury preceding dystonia could help determine the children at the highest risk for developing dystonia and thus facilitate early dystonia detection.

METHODS

We examined brain magnetic resonance images from four- to five-day-old neonates after therapeutic hypothermia for hypoxic-ischemic encephalopathy at a tertiary care center. Apparent diffusion coefficient values in the striatum and thalamus were determined using a web-based viewer integrated with the electronic medical record (IBM iConnect Access). The notes of specialists in neonatal neurology, pediatric movement disorders, and pediatric cerebral palsy (physicians most familiar with motor phenotyping after neonatal brain injury) were screened for all subjects through age of five years for motor phenotype documentation.

RESULTS

Striatal and thalamic apparent diffusion coefficient values significantly predicted dystonia with receiver operator characteristic areas under the curve of 0.862 (P = 0.0004) and 0.838 (P = 0.001), respectively (n = 50 subjects). Striatal apparent diffusion coefficient values less than 1.014 × 10^-3 mm²/s provided 100% specificity and 70% sensitivity for dystonia. Thalamic apparent diffusion coefficient values less than 0.973 × 10^-3 mm²/s provided 100% specificity and 80% sensitivity for dystonia.

CONCLUSIONS

Lower striatal and thalamic apparent diffusion coefficient values predicted dystonia in four- to five-day-old neonates who underwent therapeutic hypothermia for hypoxic ischemic encephalopathy. Objective and clinically feasible neonatal brain imaging assessment could help increase vigilance for dystonia in cerebral palsy.

A Retrospective Longitudinal Study in a Cohort of Children With Dyskinetic Cerebral Palsy Treated With Tetrabenazine

Tetrabenazine has been studied with a variety of hyperkinetic movement disorders, but there is limited and empirical literature on the potential efficacy of tetrabenazine in children with dyskinetic cerebral palsy (DCP). The purpose of this study was to evaluate the efficacy of tetrabenazine in a sample of children with DCP using the Movement Disorders—Childhood Rating Scale 4–18 Revised (MD-CRS 4–18 R). The study is a multicenter retrospective longitudinal study in which the participants were selected from the databases of each Center involved, according to detailed inclusion criteria. The study was performed on 23 children and adolescents (19 male and 4 females; mean age 8.28 years, SD 3.59) with DCP having been evaluated before starting the treatment (baseline), after 6 and 12 months of treatment and in a sub-cohort after >2 years follow-up. A linear mixed model was used to evaluate the effects of the different timings on each MD-CRS 4–18 R Index (Index I, Index II, and Global Index) adding age and type of movement disorder as random effect. A significant clinical improvement related to a reduction of MD-CRS 4-18 R Indexes was detected between the baseline and after 6 and 12 months of treatment. Findings support the efficacy of tetrabenazine in children with DCP through a standardized outcome measure (MD-CRS 4–18 R) and confirm the use of this scale as a suitable tool to detect changes in further randomized clinical trials.

The Relative Merits of an Individualized Versus a Generic Approach to Rating Functional Performance in Childhood Dystonia

Aims. The Performance Quality Rating Scale (PQRS) is an observational measure that captures performance at the level of activity and participation. Developed for use with the Cognitive Orientation to daily Occupational Performance (CO-OP), it is a highly individualized approach to measurement. CO-OP is currently being studied in childhood-onset hyperkinetic movement disorders (HMD) and deep brain stimulation. The purpose of this study was to compare two different approaches to rating performance, generic (PQRS-G) and individualized (PQRS-I), for children with childhood-onset hyperkinetic movement disorders (HMD) including dystonia. Method. Videotaped activity performances, pre and post intervention were independently scored by two blind raters using PQRS-G PQRS-I. Results were examined to determine if the measures identified differences in e performance on goals chosen by the participants and on change scores after intervention. Dependent t-tests were used to compare performance and change scores. Results. The two approaches to rating both have moderate correlations (all data: 0.764; baseline: 0.677; post-intervention: 0.725) and yielded some different results in capturing performance. There was a significant difference in scores at pre-intervention between the two approaches to rating, even though post-intervention score mean difference was not significantly different. The PQRS-I had a wider score range, capturing wider performance differences, and greater change between baseline and post-intervention performances for children and young people with dystonic movement. Conclusions. Best practice in rehabilitation requires the use of outcome measures that optimally captures performance and performance change for children and young people with dystonic movement. When working with clients with severe motor-performance deficits, PQRS-I appears to be the better approach to capturing performance and performance changes.

Glutaric acidemia type 1: Treatment and outcome of 168 patients over three decades

Glutaric acidemia type 1 (GA1) is a disorder of cerebral organic acid metabolism resulting from biallelic mutations of GCDH. Without treatment, GA1 causes striatal degeneration in >80% of affected children before two years of age. We analyzed clinical, biochemical, and developmental outcomes for 168 genotypically diverse GA1 patients managed at a single center over 31 years, here separated into three treatment cohorts: children in Cohort I (n = 60; DOB 2006-2019) were identified by newborn screening (NBS) and treated prospectively using a standardized protocol that included a lysine-free, arginine-enriched metabolic formula, enteral l-carnitine (100 mg/kg•day), and emergency intravenous (IV) infusions of dextrose, saline, and l-carnitine during illnesses; children in Cohort II (n = 57; DOB 1989-2018) were identified by NBS and treated with natural protein restriction (1.0-1.3 g/kg•day) and emergency IV infusions; children in Cohort III (n = 51; DOB 1973-2016) did not receive NBS or special diet. The incidence of striatal degeneration in Cohorts I, II, and III was 7%, 47%, and 90%, respectively (p < .0001). No neurologic injuries occurred after 19 months of age. Among uninjured children followed prospectively from birth (Cohort I), measures of growth, nutritional sufficiency, motor development, and cognitive function were normal. Adherence to metabolic formula and l-carnitine supplementation in Cohort I declined to 12% and 32%, respectively, by age 7 years. Cessation of strict dietary therapy altered plasma amino acid and carnitine concentrations but resulted in no serious adverse outcomes. In conclusion, neonatal diagnosis of GA1 coupled to management with lysine-free, arginine-enriched metabolic formula and emergency IV infusions during the first two years of life is safe and effective, preventing more than 90% of striatal injuries while supporting normal growth and psychomotor development. The need for dietary interventions and emergency IV therapies beyond early childhood is uncertain.

High Frequency Deep Brain Stimulation of Superior Cerebellar Peduncles in a Patient with Cerebral Palsy

Background

Globus pallidus internus (GPi) deep brain stimulation (DBS) is widely used in patients with isolated dystonia; however, its use remains controversial in patients with acquired dystonia and cerebral palsy.

Case presentation

We report the first case of a cerebral palsy patient, who failed to recover 2 years after GPi DBS; DBS was administered on both superior cerebellar peduncles (SCPs) and dentate nuclei (DNs). The monopolar stimulation results suggested that DBS was better administered via the SCPs than via the DNs. At six months follow-up, the patient exhibited a significant improvement of dystonia and spasticity, as well as in her quality of life.

Discussion

SCP DBS may be a potential treatment for cerebral palsy patients with dystonia and spasticity who do not respond well to GPi DBS.

Treatment of Disorders of Tone and Other Considerations in Pediatric Movement Disorders

Pediatric movement disorders (PMDs) consist of a heterogeneous group of signs and symptoms caused by numerous neurological diseases. Different neurological disorders in children also share overlapping movement disorders making a diagnosis of the underlying cause of the movement disorder challenging. The similarity of the symptoms across multiple disease types suggests that there may be a final common motor pathway causing the overlapping movement disorders. There are numerous disorders in children associated with disturbances in tone and involuntary movements. This chapter will focus primarily on those disorders that involve abnormalities of tone and other important considerations of pediatric movement disorders. This chapter will address rating scales and goals for treatment and will include a review of symptomatic treatment and, where possible, the treatment of the underlying disease processes. The chapter will review representative disorders, including an inborn error of metabolism, an autoimmune disorder, and a group of neurodegenerative disorders. These examples demonstrate how the disorder's underlying pathophysiology results in a specific approach to the underlying disease and the associated conditions of tone and involuntary movements. Finally, the multiple treatment options for cerebral palsy and considerations of cerebral palsy mimics will be discussed.

Deep brain stimulation reduces pain in children with dystonia, including in dyskinetic cerebral palsy

AIM

To establish the prevalence of dystonic pain in children and their response to deep brain stimulation (DBS).

METHOD

Dystonic pain was assessed in a cohort of 140 children, 71 males and 69 females, median age 11 years 11 months (range 3y-19y 1mo), undergoing DBS in our centre over a period of 10 years. The cohort was divided into aetiological dystonia groups: 1a, inherited; 1b, heredodegenerative; 2, acquired; and 3, idiopathic. Motor responses were measured with the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS).

RESULTS

Dystonic pain was identified in 63 (45%) patients, 38% of whom had a diagnosis of cerebral palsy (CP). Dystonic pain improved in 90% of children and in all aetiological subgroups 1 year after DBS, while the BFMDRS motor score improved in 70%. Statistically significant improvement (p<0.01) was noted for the whole cohort on the Numerical Pain Rating Scale (n=27), Paediatric Pain Profile (n=17), and Caregivers Priorities and Child Health Index of Life with Disabilities questionnaire (n=48). There was reduction of pain severity, frequency, and analgesia requirement. Findings were similar for the whole cohort and aetiological subgroups other than the inherited heredodegenerative group where the improvement did not reach statistical significance.

INTERPRETATION

Dystonic pain is frequent in children with dystonia, including those with CP, who undergo DBS; this can be an important, realizable goal of surgery irrespective of aetiology. We encourage the use of multimodal approach in pain research to reduce the risk of bias.

Deep brain stimulation for the treatment of cerebral palsy: A review

Deep brain stimulation (DBS) has been used as a safe and effective neuromodulation technique for treatment of various diseases. A large number of patients suffering from movement disorders such as dyskinesia may benefit from DBS. Cerebral palsy (CP) is a group of permanent disorders mainly involving motor impairment, and medical interventions are usually unsatisfactory or temporarily active, especially for dyskinetic CP. DBS may be another approach to the treatment of CP. In this review we discuss the targets for DBS and the mechanisms of action for the treatment of CP, and focus on presurgical assessment, efficacy for dystonia and other symptoms, safety, and risks.

Medical Updates in Management of Hypertonia

Identifying the subtypes of hypertonia is becoming increasingly important. Treatment strategies, including tone-modulating surgical interventions, medication type and dosing, and chemodenervation, may differ depending on the type of hypertonia present. It is important to delineate how hypertonia interferes with function and quality of life so that the appropriate intervention can be selected at the right time. Outcomes of treatment depend heavily on clear communication of goals. Botulinum toxin should not be used in isolation but as an adjunct to rehabilitation modalities.

Movement disorders after hypoxic brain injury following cardiac arrest in adults

BACKGROUND AND PURPOSE

Post-hypoxic movement disorders and chronic post-hypoxic myoclonus are rare complications after cardiac arrest in adults. Our study investigates the clinical spectrum, neuroimaging results, therapy and prognosis of these debilitating post-hypoxic sequelae.

METHODS

This retrospective study included 72 patients from the neurological intensive care unit at a university hospital, who were diagnosed with hypoxic-ischaemic encephalopathy after cardiac arrest between January 2007 and September 2018. Clinical records were screened for occurrence of post-hypoxic movement disorders and chronic post-hypoxic myoclonus. Affected patients were further analysed for applied neuroprognostic tests, administered therapy and treatment response, and the outcome of these movement disorders and neurological function.

RESULTS

Nineteen out of 72 screened patients exhibited post-hypoxic motor symptoms. Basal ganglia injury was the most likely neuroanatomical correlate of movement disorders as indicated by T1 hyperintensities and hypometabolism of this region in magnetic resonance imaging and positron emission tomography computed tomography. Levomepromazine and intrathecal baclofen showed first promising and mostly prompt responses to control these post-hypoxic movement disorders and even hyperkinetic storms. In contrast, chronic post-hypoxic myoclonus best responded to co-application of clonazepam, levetiracetam and primidone. Remission rates of post-hypoxic movement disorders and chronic post-hypoxic myoclonus were 58% and 50%, respectively. Affected patients seemed to present a rather good recovery of cognitive functions in contrast to the often more severe physical deficits.

CONCLUSIONS

Post-hypoxic movement disorders associated with pronounced basal ganglia dysfunction might be efficiently controlled by levomepromazine or intrathecal baclofen. Their occurrence might be an indicator for a more unfavourable, but often not devastating, neurological outcome.

Limited Utility for Benzodiazepines in Chronic Pain Management: A Narrative Review

INTRODUCTION

Controversy and uncertainty exist about the use of benzodiazepine receptor agonists (BZRAs) in pain management. This article curates available research to determine the appropriate role of BZRAs in the course of pain management, and how prescribers might address these challenges.

METHODS

A narrative review was performed to determine the appropriate role of BZRAs in pain management and to develop practice recommendations. Publications were identified by a search of PubMed, references of retrieved reports, guidelines, and the author's personal files.

RESULTS

BZRAs were found to have analgesic benefit for two pain conditions: burning mouth syndrome and stiff person syndrome. Absence of research, heterogeneity of trials, and small sample sizes precluded drawing conclusions about efficacy of BZRAs for the other 109 pain conditions explored. Data supports the use of BZRAs to treat co-occurring insomnia and anxiety disorders but only when alternatives are inadequate and only for short periods of time (2-4 weeks). The utility of BZRAs is limited by loss of efficacy that may be seen with continued use and adverse reactions including physiologic dependence which develops in 20-100% of those who take these agents for more than a month.

CONCLUSIONS

BZRAs are often used inappropriately in pain management. Their initiation and duration of use should be limited to a narrow range of conditions. When prescribed for 4 weeks or more, patients should be encouraged to discontinue them through a supported, slow tapering process that may take 12-18 months or longer.