Prospective open-label clinical trial of trihexyphenidyl in children with secondary dystonia due to cerebral palsy

Physician Approaches to the Pharmacologic Treatment of Dystonia in Cerebral Palsy

Objective

To determine how physicians approach pharmacologic dystonia treatment in people with CP and assess physician readiness to participate in a randomized trial comparing existing pharmacologic dystonia treatments.

Methods

We administered a REDCap survey to physician members of the American Academy of Cerebral Palsy and Developmental Medicine and of the Child Neurology Society to assess which pharmacologic agents they use to treat dystonia in CP and their preferred indications and dosing.

Results

Of 479 physicians surveyed, 240 (50%) responded. Respondents treated functionally limiting (95%) and generalized (57%) dystonia and most commonly used six medications: baclofen (95%), trihexyphenidyl (79%), gabapentin (67%), carbidopa/levodopa (55%), clonazepam (55%), and diazepam (54%). Baclofen was preferred in people with co-existing spasticity (81%), gabapentin was preferred in people with co-existing pain (49%), and trihexyphenidyl was avoided in people with constipation (34%) or urinary retention (42%). Preferred dosing regimens followed published regimens for dystonia, when available, but otherwise followed published regimens for other CP symptoms (spasticity and seizures). Baclofen was preferred by 64% of respondents as first line treatment, but there was no clear consensus on second or third-line medications. Most respondents (51%) were comfortable randomizing their patients to receive any of the six most commonly used medications used to treat dystonia in CP.

Conclusions

This study summarizes current indications and dosing for the six most commonly used medications to treat dystonia in CP as per treating physicians in the US and Canada and also demonstrates physician support for a randomized trial comparing the effectiveness of these treatments.

Comparative Efficacy and Side Effect Profiles of Interventions for Pediatric Saliva Control: A Cohort Study

OBJECTIVE

To compare efficacy and side effect profile data on conservative, behavioral, pharmacological, and surgical treatments used for pediatric saliva control.

STUDY DESIGN

A cohort study of children (n = 483) referred to a specialty Saliva Control service between May 2014 and November 2019 was performed, using quantitative data from pretreatment and post-treatment questionnaires (the Drooling Impact Scale [DIS], Drooling Rating Scale [DRS]) and recording of side effects. Overall, 483 children were included; treatment choices were based on published international guidelines.

RESULTS

The greatest improvement was seen after intraglandular botulinum toxin A (BTX-A) injections (n = 207; 551 courses; mean DIS change, 34.7; 95% CI = 29.2-35.7) or duct transpositional surgery (n = 31; mean change in DIS, 29.0; 95% CI, 22.3-35.7). Oral anticholinergics were associated with good outcomes, with no significant statistical difference between glycopyrronium bromide (n = 150; mean DIS change, 21.5; 95% CI, 19.1-24.0) or trihexyphenidyl (n = 87; mean DIS change, 22.4; 95% CI, 18.9-25.8). Inhaled ipratropium bromide was not as efficacious (n = 80; mean DIS change, 11.1; 95% CI, 8.9-13.3). Oromotor programs were used in a selected group with reliable outcomes (n = 9; mean DIS change, 13.0). Side effects were consistent with previous studies. Overall, in cases of milder severity, enterally administered therapies provided a good first-line option. With more severe problems, BTX-A injections or saliva duct transpositional surgery were more effective and well tolerated.

CONCLUSIONS

We describe a large, single-center pediatric saliva control cohort, providing direct comparison of the efficacy and side effect profiles for all available interventions and inform clinical practice for specialists when considering different options. BTX-A injections or saliva duct transpositional surgery seem to be more effective for saliva control that is more severe.

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.

Gabapentin as Add-on Therapy to Trihexyphenidyl in Children with Dyskinetic Cerebral Palsy: A Randomized, Controlled Trial

OBJECTIVE

To compare the efficacy of gabapentin as add-on therapy to trihexyphenidyl in the treatment of children with dyskinetic cerebral palsy (CP).

METHODS

An open-labelled, randomized, controlled trial was conducted among children aged 3-9 y with dyskinetic CP [Gross Motor Functional Classification System (GMFCS) 4-5]. Participants were assigned into two groups: gabapentin with trihexyphenidyl (n = 30) and trihexyphenidyl alone (n = 30). Dyskinesia Impairment Scale (DIS), Dystonia Severity Assessment Plan (DSAP), and International Classification of Functioning, Disability, and Health-Children and Youth Version (ICF-CY) were measured at baseline, 4 and 12 wk.

RESULTS

There was significant reduction in baseline dystonia in both the groups (DIS: p < 0.001; DSAP: p = 0.007; ICF-CY: p < 0.001) but when data were compared between the groups, there was no significant difference in the severity of dystonia at 4 wk and at 12 wk (DIS: p = 0.09; DSAP: p = 0.49; ICF-CY: p = 0.25). Constipation was the commonest side effect observed in both the groups [3 (11.5%) vs. 4 (14.3%)].

CONCLUSION

Trihexyphenidyl alone is as effective as combination of gabapentin with trihexyphenidyl in decreasing the severity of dystonia at 12 wk. Hence, there is no added benefit of gabapentin as add-on therapy for dystonia among children with dyskinetic CP.

TRIAL REGISTRATION

CTRI/2019/04/018603.

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.

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.

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.

Dystonia and leveraging oral pharmacotherapy

Dystonia is a clinically diverse disorder, characterized by sustained or intermittent muscle contractions causing abnormal and often repetitive movements and/or postures. Accurate clinical diagnosis is tantamount to effective dystonia management. Current guidelines in the treatments of dystonia, including oral therapy, are prescribed to improve symptoms and to restore functional capacity. Identifying treatable causes from co-existing phenomenologies is relevant to provide the most optimal and disease-specific medications. In other forms of dystonia, genetic factors may affect outcome. Moreover, proper selection of patients, early initiation of medications and customized drug titration are keys to increasing the chances of success when using oral therapies for dystonia. Treatment of dystonia primarily involves agents that target dopamine and acetylcholine receptors. Other drugs used include benzodiazepines, baclofen, antiepileptics, some antipsychotics drugs and antihistamine, with different levels of evidence of effectiveness. Unfortunately, most of the widely used drugs have low levels of evidence and are primarily based on anecdotal experiences. Finally, other adjunctive therapeutic strategies are often necessary to complement oral therapy.

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.

Orthopaedic Surgery in Dystonic Cerebral Palsy

BACKGROUND

Outcomes after orthopaedic interventions in patients with dystonic cerebral palsy (DCP) are historically regarded as unpredictable. This study aims to evaluate the overall outcome of orthopaedic surgery in children with DCP.

METHOD

Children with DCP who underwent lower limb orthopaedic surgery with a minimum follow-up of 12 months were included. Data collected included age at time of surgery, surgical procedures performed, Gross Motor Function Classification System (GMFCS) level, and Barry Albright Dystonia Scale (BADS) score. The cohort was divided into 2 groups. Group 1 (GMFCS levels I to III), mean age 12 years 7 months and group 2 (GMFCS levels IV to V), mean age 10 years 7 months. Group 1 had surgery aimed at deformity correction to improve gait and mobility, and group 2 for the management or prevention of hip displacement. Outcome measures analyzed were: the incidence of unpredictable results related to surgery and early recurrence of deformity in both groups. Functional mobility scale scores were evaluated for group 1 and hip migration percentage for group 2. Linear mixed models were used to take into account repeated measures over time and correlations between measurements from the same patient.

RESULTS

Group 1 (n=18); had low BADS scores and were considered to have mild dystonia. Three children experienced unpredictable results, 2 had early recurrence of deformity, 3 had a decline, and 1 child improved in the functional mobility scale.Group 2 (n=19); had high BADS scores and were considered to have moderate to severe dystonia. Nine surgical events involved bony procedures and 15 were soft tissue surgery only. One surgical event lead to unpredictable results and 2 children had early recurrence of deformity. Postoperatively, a linear trend of increasing migration percentage [0.49% (95% confidence interval, 0.23-0.74; P=0.0002)] was seen up to 21 months. There was no significant change after 21 months [-0.08% (95% confidence interval, -0.24 to +0.041; P=0.18)].

CONCLUSIONS

This study suggests that unpredictable results and early recurrence of deformity following orthopaedic surgery in children with DCP are not as common as previously regarded. Furthermore, functional mobility and hip morphology can be improved.

LEVEL OF EVIDENCE

Level IV-this is a case-series.

Current therapies and therapeutic decision making for childhood-onset movement disorders

Movement disorders differ in children to adults. First, neurodevelopmental movement disorders such as tics and stereotypies are more prevalent than parkinsonism, and second, there is a genomic revolution which is now explaining many early-onset dystonic syndromes. We outline an approach to children with movement disorders starting with defining the movement phenomenology, determining the level of functional impairment due to abnormal movements, and screening for comorbid psychiatric conditions and cognitive impairments which often contribute more to disability than the movements themselves. The rapid improvement in our understanding of the etiology of movement disorders has resulted in an increasing focus on precision medicine, targeting treatable conditions and defining modifiable disease processes. We profile some of the key disease-modifying therapies in metabolic, neurotransmitter, inflammatory, and autoimmune conditions and the increasing focus on gene or cellular therapies. When no disease-modifying therapies are possible, symptomatic therapies are often all that is available. These classically target dopaminergic, cholinergic, alpha-adrenergic, or GABAergic neurochemistry. Increasing interest in neuromodulation has highlighted that some clinical syndromes respond better to DBS, and further highlights the importance of "disease-specific" therapies with a future focus on individualized therapies according to the genomic findings or disease pathways that are disrupted. We summarize some pragmatic applications of symptomatic therapies, neuromodulation techniques, and some rehabilitative interventions and provide a contemporary overview of treatment in childhood-onset movement disorders. © 2019 International Parkinson and Movement Disorder Society.

A Computational Model of Deep-Brain Stimulation for Acquired Dystonia in Children

The mechanism by which deep brain stimulation (DBS) improves dystonia is not understood, partly heterogeneity of the underlying disorders leads to differing effects of stimulation in different locations. Similarity between the effects of DBS and the effects of lesions has led to biophysical models of blockade or reduced transmission of involuntary activity in individual cells in the pathways responsible for dystonia. Here, we expand these theories by modeling the effect of DBS on populations of neurons. We emphasize the important observation that the DBS signal itself causes surprisingly few side effects and does not normally appear in the electromyographic signal. We hypothesize that, at the population level, massively synchronous rhythmic firing caused by DBS is only poorly transmitted through downstream populations. However, the high frequency of stimulation overwhelms incoming dystonic activity, thereby substituting an ineffectively transmitted exogenous signal for the endogenous abnormal signal. Changes in sensitivity can occur not only at the site of stimulation, but also at downstream sites due to synaptic and homeostatic plasticity mechanisms. The mechanism is predicted to depend strongly on the stimulation frequency. We provide preliminary data from simultaneous multichannel recordings in basal ganglia and thalamus in children with secondary dystonia. We also provide illustrative simulations of the effect of stimulation frequency on the transmission of the DBS pulses through sequential populations of neurons in the dystonia pathway. Our experimental results and model provide a new hypothesis and computational framework consistent with the clinical features of DBS in childhood acquired dystonia.

Trihexyphenidyl for dystonia in cerebral palsy

BACKGROUND

Cerebral palsy occurs in up to 2.1 of every 1000 live births and encompasses a range of motor problems and movement disorders. One commonly occurring movement disorder amongst those with cerebral palsy is dystonia: sustained or intermittent involuntary muscle spasms and contractions that cause twisting, repetitive movements and abnormal postures. The involuntary contractions are often very painful and distressing and cause significant limitations to activity and participation.Oral medications are often the first line of medical treatment for dystonia. Trihexyphenidyl is one such medication that clinicians often use to treat dystonia in people with cerebral palsy.

OBJECTIVES

To assess the effects of trihexyphenidyl in people with dystonic cerebral palsy, according to the World Health Organization's (WHO) International Classification of Functioning, Disability and Health (ICF) domains of impairment, activity and participation. We also assessed the type and incidence of adverse effects in people taking the drug.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, eight other databases and two trials registers in May 2017, and we checked reference lists and citations to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials comparing oral trihexyphenidyl versus placebo for dystonia in cerebral palsy. We included studies in children and adults of any age with dystonic cerebral palsy, either in isolation or with the associated movement disorders of spasticity, ataxia, chorea, athetosis and/or hypotonia. We included studies regardless of whether or not the study authors specified the method used to diagnose dystonia in their study population. Primary outcomes were change in dystonia and adverse effects. Secondary outcomes were: activity, including mobility and upper limb function; participation in activities of daily living; pain; and quality of life.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We identified one study, which was set in Australia, that met the inclusion criteria. This was a randomised, double-blind, placebo-controlled, cross-over trial in 16 children (10 boys and 6 girls) with predominant dystonic cerebral palsy and a mean age of 9 years (standard deviation 4.3 years, range 2 to 17 years). We considered the trial to be at low risk of selection, performance, detection, attrition, reporting and other sources of bias. We rated the GRADE quality of the evidence as low.We found no difference in mean follow-up scores for change in dystonia as measured by the Barry Albright Dystonia Scale (BADS), which assesses eight body regions for dystonia on a 5-point scale (0 = none to 4 = severe), resulting in a total score of 0 to 32. The BADS score was 2.67 points higher (95% confidence interval (CI) -2.55 to 7.90; low-quality evidence), that is, worse dystonia, in the treated group. Trihexyphenidyl may be associated with an increased risk of adverse effects (risk ratio 2.54, 95% CI 1.38 to 4.67; low-quality evidence).There was no difference in mean follow-up scores for upper limb function as measured by the Quality of Upper Extremity Skills Test, which has four domains that collectively assess 36 items (each scored 1 or 2) and produces a total score of 0 to 100. The score in the treated group was 4.62 points lower (95% CI -10.98 to 20.22; low-quality evidence), corresponding to worse function, than in the control group. We found low-quality evidence for improved participation (as represented by higher scores) in the treated group in activities of daily living, as measured by three tools: 18.86 points higher (95% CI 5.68 to 32.03) for the Goal Attainment Scale (up to five functional goals scored on 5-point scale (-2 = much less than expected to +2 = much more than expected)), 2.91 points higher (95% CI 1.01 to 4.82) for the satisfaction subscale of the Canadian Occupational Performance Measure (COPM; satisfaction with performance in up to five problem areas scored on a 10-point scale (1 = not satisfied at all to 10 = extremely satisfied)), and 2.24 points higher (95% CI 0.64 to 3.84) for performance subscale of the COPM (performance in up to five problem areas scored on a 10-point scale (1 = not able to do to; 10 = able to do extremely well)).The study did not report on pain or quality of life.

AUTHORS' CONCLUSIONS

At present, there is insufficient evidence regarding the effectiveness of trihexyphenidyl for people with cerebral palsy for the outcomes of: change in dystonia, adverse effects, increased upper limb function and improved participation in activities of daily living. The study did not measure pain or quality of life. There is a need for larger randomised, controlled, multicentre trials that also examine the effect on pain and quality of life in order to determine the effectiveness of trihexyphenidyl for people with cerebral palsy.

Management of Pediatric Movement Disorders: Present and Future

Management of movement disorders in children is an evolving field. This article outlines the major categories of treatment options for pediatric movement disorders and general guidelines for their use. We review the evidence for existing therapies, which continue to lack large-scale controlled trials to guide treatment decisions. The field continues to rely on extrapolations from adult studies and lower quality evidence such as case reports and case series to guide treatment guidelines and consensus statements. Developments in new pharmaceuticals for rare diseases have begun to provide hope for those cases in which a genetic diagnosis can be made. Advances in surgical therapies such as deep brain stimulation as well as new modes of treatment such as gene therapy, epigenetic modulation, and stem cell therapy hold promise for improving outcomes in both primary and secondary causes of movement disorders. There is a critical need for larger, multicenter, controlled clinical trials to fully evaluate treatments for pediatric movement disorders.

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

AIM

To systematically review evidence for pharmacological/neurosurgical interventions for managing dystonia in individuals with cerebral palsy (CP) to inform a care pathway.

METHOD

Searches included studies with a minimum of five participants with dystonia in CP receiving oral baclofen, benzodiazepines (clonazepam, diazepam, lorazepam), clonidine, gabapentin, levodopa, trihexyphenidyl, botulinum toxin, intrathecal baclofen (ITB), or deep brain stimulation (DBS). Evidence was classified according to American Academy of Neurology guidelines.

RESULTS

Twenty-eight articles underwent data extraction: one levodopa, five trihexyphenidyl, three botulinum toxin, six ITB, and 13 DBS studies. No articles for oral baclofen, benzodiazepines, clonidine, or gabapentin met the inclusion criteria. Evidence for reducing dystonia was level C (possibly effective) for ITB and DBS; level C (possibly ineffective) for trihexyphenidyl; and level U (inadequate data) for botulinum toxin.

INTERPRETATION

For dystonia reduction, ITB and DBS are possibly effective, whereas trihexyphenidyl was possibly ineffective. There is insufficient evidence to support oral medications or botulinum toxin to reduce dystonia. There is insufficient evidence for pharmacological and neurosurgical interventions to improve motor function, decrease pain, and ease caregiving. The majority of the pharmacological and neurosurgical management of dystonia in CP is based on clinical expert opinion.

WHAT THIS PAPER ADDS

Intrathecal baclofen and deep brain stimulation are possibly effective in reducing dystonia. Current evidence does not support effectiveness of oral medications or botulinum toxin to reduce dystonia. Evidence is inadequate for pharmacological/neurosurgical interventions impact on improving motor function, pain/comfort, and easing caregiving. The majority of the care pathway rests on expert opinion.

Oral medication prescription practices of tertiary-based specialists for dystonia in children with cerebral palsy

AIM

To examine current clinical practice for prescribing medications for children with dystonic cerebral palsy (CP) by medical doctors working at a tertiary care centre.

METHODS

Rehabilitation and developmental paediatric specialists completed: (i) a custom-designed online cross-sectional survey capturing their usual prescribing patterns; and (ii) one-page questionnaires detailing medication prescription for each child with CP who they started on a new medication for dystonia over a 12-month period.

RESULTS

Eleven participating doctors ranged in experience in managing children with CP from less than 5 years to more than 20 years. The cross-sectional survey showed that most doctors used more than one medication, with six making choices taking into account four or more different medications. Oral baclofen was used by all doctors and was the first choice of 10 of 11. Prospective surveys from 57 children showed that medication was prescribed mainly for children aged 3-10 years (n = 35/57), classified within Gross Motor Function Classification System levels IV and V (n = 40/57) and with a mixed movement disorder (n = 38/57). Gabapentin and baclofen were the most frequently prescribed (n = 21/57 and 19/57, respectively), with other drugs used less frequently. Dosage regimens varied between and within doctors, particularly for the use of gabapentin and diazepam.

CONCLUSIONS

Oral medication prescribing practices varied among doctors managing children with dystonic CP at a tertiary care hospital, particularly with respect to dosing. There is a need for clinical guidelines for medication prescription to be developed based on best evidence and consensus by clinical experts.

Efficacy of oral pharmacological treatments in dyskinetic cerebral palsy: a systematic review

AIM

To evaluate the actual evidence of efficacy of oral pharmacological treatments in the management of dyskinetic cerebral palsy (CP).

METHOD

A systematic review was performed according to the American Academy for Cerebral Palsy and Developmental Medicine (AACPDM) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. Articles were searched for in PubMed/MEDLINE, Scopus, Web of Science, Cochrane Library, Database of Reviews of Effectiveness, OTSeeker, Physiotherapy Evidence Database, REHABDATA, and ClinicalTrials.gov.

RESULTS

Sixteen articles met the eligibility criteria. Eight studies on trihexyphenidyl and two on levodopa showed contradictory results. Low efficacy was reported for diazepam, dantrolene sodium, perphenazine, and etybenzatropine. Tetrabenazine, gabapentin and levetiracetam should be studied in more detail. The updated available evidence does not support any therapeutic algorithm for the management of dyskinetic CP.

INTERPRETATION

This lack of evidence is partially owing to the inconsistency of classifications of patients and of outcome measures used in the reviewed studies. Further randomized, double-blind, placebo-controlled pharmacological trials, optimized for different age groups, based on valid, reliable, and disease-specific rating scales are strongly needed. Outcome measures should be selected within the framework of the International Classification of Functioning, Disability and Health.

WHAT THIS PAPER ADDS

Evidence to prove (or disprove) the efficacy of oral drugs in dyskinetic cerebral palsy is low. The most investigated drugs, trihexyphenidyl and levodopa, show contradictory results. Tetrabenazine, levetiracetam, and gabapentin efficacy should be studied in more detail. Lack of evidence is partially due to the inconsistency of classifications and outcome measures used. Outcome measures should be selected within the framework of the International Classification of Functioning, Disability and Health in next clinical trials.

Clinical Management of Dystonia in Childhood

Dystonia is one of the most frequent movement disorders in childhood. It can impede normal motor development and cause significant motor disability. The diagnostic evaluation of childhood dystonia is challenging due to the phenotypic variability and heterogeneous etiologies. Evidence to guide the diagnostic evaluation and treatment is limited. Assessment is primarily directed by clinical history and distinctive examination findings. Neuroimaging is typically necessary to evaluate for acquired or complex inherited dystonias. A trial of levodopa can be both diagnostic and therapeutic in children with dopa-responsive dystonia. However, for the majority of children with early-onset dystonia, treatment is symptomatic with varying efficacy. There is a paucity of therapeutic trials for childhood dystonia and most treatment recommendations are consensus or expert opinion driven. This review summarizes the available evidence and guidelines on the diagnostic evaluation and pharmacological treatment of childhood-onset dystonia and provides practical frameworks to approach both issues based on best evidence.

Clinical presentation and management of dyskinetic cerebral palsy

Cerebral palsy is the most frequent cause of severe physical disability in childhood. Dyskinetic cerebral palsy (DCP) is the second most common type of cerebral palsy after spastic forms. DCP is typically caused by non-progressive lesions to the basal ganglia or thalamus, or both, and is characterised by abnormal postures or movements associated with impaired tone regulation or movement coordination. In DCP, two major movement disorders, dystonia and choreoathetosis, are present together most of the time. Dystonia is often more pronounced and severe than choreoathetosis, with a major effect on daily activity, quality of life, and societal participation. The pathophysiology of both movement disorders is largely unknown. Some emerging hypotheses are an imbalance between indirect and direct basal ganglia pathways, disturbed sensory processing, and impaired plasticity in the basal ganglia. Rehabilitation strategies are typically multidisciplinary. Use of oral drugs to provide symptomatic relief of the movement disorders is limited by adverse effects and the scarcity of evidence that the drugs are effective. Neuromodulation interventions, such as intrathecal baclofen and deep brain stimulation, are promising options.

Proposed recommendations for diagnosing and managing individuals with glutaric aciduria type I: second revision

Glutaric aciduria type I (GA-I; synonym, glutaric acidemia type I) is a rare inherited metabolic disease caused by deficiency of glutaryl-CoA dehydrogenase located in the catabolic pathways of L-lysine, L-hydroxylysine, and L-tryptophan. The enzymatic defect results in elevated concentrations of glutaric acid, 3-hydroxyglutaric acid, glutaconic acid, and glutaryl carnitine in body tissues, which can be reliably detected by gas chromatography/mass spectrometry (organic acids) and tandem mass spectrometry (acylcarnitines). Most untreated individuals with GA-I experience acute encephalopathic crises during the first 6 years of life that are triggered by infectious diseases, febrile reaction to vaccinations, and surgery. These crises result in striatal injury and consequent dystonic movement disorder; thus, significant mortality and morbidity results. In some patients, neurologic disease may also develop without clinically apparent crises at any age. Neonatal screening for GA-I us being used in a growing number of countries worldwide and is cost effective. Metabolic treatment, consisting of low lysine diet, carnitine supplementation, and intensified emergency treatment during catabolism, is effective treatment and improves neurologic outcome in those individuals diagnosed early; treatment after symptom onset, however, is less effective. Dietary treatment is relaxed after age 6 years and should be supervised by specialized metabolic centers. The major aim of this second revision of proposed recommendations is to re-evaluate the previous recommendations (Kölker et al. J Inherit Metab Dis 30:5-22, 2007b; J Inherit Metab Dis 34:677-694, 2011) and add new research findings, relevant clinical aspects, and the perspective of affected individuals.

The Symptomatic Treatment of Acquired Dystonia: A Systematic Review

Background

Acquired dystonia is caused by an acquired or exogenous event. Although the therapeutic armamentarium used in clinical practice is more or less similar to that used for inherited or idiopathic dystonia, formal proof of the efficacy of these interventions in acquired dystonia is lacking.

Methods

The authors attempt to provide a comprehensive and systematic review of the current evidence for medical and allied health care treatment strategies in acquired dystonias. The PubMed, Cochrane Library, MEDLINE, Web of Science, PiCarta, and PsycINFO databases were searched up to December 2015, including randomized controlled trials, patient-control studies, and case series or single case reports containing a report on clinical outcome.

Results

There are level 3 practice recommendations for botulinum toxin injections and globus pallidus pars interna deep brain stimulation for tardive dystonia and dystonic cerebral palsy as well as intrathecal baclofen for dystonic cerebral palsy. There are insufficient and conflicting data on the effect (vs. the hazard) of other pharmacological interventions, and limited work has been done on other forms of neurostimulation and allied health care. Because no class A1 or A2 studies were identified, level 1 or 2 practice recommendations could not be deducted for a specific treatment intervention.

Conclusions

To improve the current medical and allied health care treatment options for patients with acquired dystonia, high-quality trials that examine the efficacy of therapies need to be performed.

Diagnosis and treatment of dystonia

The dystonias are a group of disorders characterized by excessive involuntary muscle contractions leading to abnormal postures and/or repetitive movements. A careful assessment of the clinical manifestations is helpful for identifying syndromic patterns that focus diagnostic testing on potential causes. If a cause is identified, specific etiology-based treatments may be available. In most cases, a specific cause cannot be identified, and treatments are based on symptoms. Treatment options include counseling, education, oral medications, botulinum toxin injections, and several surgical procedures. A substantial reduction in symptoms and improved quality of life is achieved in most patients by combining these options.

Acute colonic pseudo-obstruction in a child taking trihexyphenidyl for drooling: Prescribers beware

Colonic pseudo-obstruction (Ogilvie's Syndrome) in children is relatively uncommon. We report an unusual case of colonic pseudo-obstruction in an 8-year-old child with cerebral palsy and long-term hypomotility issues being treated for drooling with the anticholinergic medication trihexyphenidyl. He presented as an emergency with severe abdominal distension, abdominal tenderness and vomiting. An emergency laparotomy revealed colonic dilatation and a defunctioning ileostomy was created. To our knowledge, this is the first case reporting colonic pseudo-obstruction as a possible complication of treatment with trihexyphenidyl. We suggest prescribers should exercise caution when prescribing trihexyphenidyl in patients with long-term intestinal hypomotility issues.

Current and emerging strategies for treatment of childhood dystonia

Childhood dystonia is a movement disorder characterized by involuntary sustained or intermittent muscle contractions causing twisting and repetitive movements, abnormal postures, or both (Sanger et al, 2003). Dystonia is a devastating neurological condition that prevents the acquisition of normal motor skills during critical periods of development in children. Moreover, it is particularly debilitating in children when dystonia affects the upper extremities such that learning and consolidation of common daily motor actions are impeded. Thus, the treatment and rehabilitation of dystonia is a challenge that continuously requires exploration of novel interventions. This review will initially describe the underlying neurophysiological mechanisms of the motor impairments found in childhood dystonia followed by the clinical measurement tools that are available to document the presence and severity of symptoms. Finally, we will discuss the state-of-the-art of therapeutic options for childhood dystonia, with particular emphasis on emergent and innovative strategies.

Pharmacological interventions for pain in children and adolescents with life-limiting conditions

BACKGROUND

Pain is one of the most common symptoms in children and young people (CYP) with life-limiting conditions (LLCs) which include a wide range of diagnoses including cancer. The current literature indicates that pain is not well managed, however the evidence base to guide clinicians is limited. There is a clear need for evidence from a systematic review to inform prescribing.

OBJECTIVES

To evaluate the evidence on the effectiveness of different pharmacological interventions used for pain in CYP with LLCs.

SEARCH METHODS

The following electronic databases were searched up to December 2014: CENTRAL (in the Cochrane Library), MEDLINE, EMBASE, PsycINFO and CINAHL. In addition, we searched conference proceedings and reference lists of included studies. For completeness, we also contacted experts in the field. No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-randomised studies and other studies that included a clearly defined comparator group were included. The studies investigated pharmacological treatments for pain associated with LLCs in CYP. The treatment included those specifically developed to treat pain and those that acted as an adjuvant, where the treatment was not primarily developed to treat pain but has pain relieving properties. The LLC was identified by its inclusion in the Richard Hain Directory of LLCs.

DATA COLLECTION AND ANALYSIS

Citations were screened by five review authors. Data were extracted by one review author and checked by a second. Two review authors assessed the risk of bias of included studies. A sufficient number of studies using homogeneous outcomes was not identified so a meta-analysis was not possible.

MAIN RESULTS

We identified 24,704 citations from our database search. Nine trials with 379 participants fulfilled our inclusion criteria. Participants had cerebral palsy (CP) in five of the studies and osteogenesis imperfecta (OI) in the other four. Participants across the trials ranged in age from 2 to 19 years. All studies, apart from one cross-over trial, were parallel designed RCTs. Three of the trials on CP evaluated intrathecal baclofen (ITB) and two botulinum toxin A (BoNT-A). All of the OI trials evaluated the use of bisphosphonates (two alendronate and one pamidronate). No trials were identified that evaluated a commonly used analgesic in this patient group. Pain was a secondary outcome in five of the eight identified studies. Overall the quality of the trials was mixed. Only one study involved over 100 participants.For the two ITB studies for pain in CP, in the same study population but assessed at different time points in their disease, both found an effect on pain favouring the intervention compared to the control group (standard care or placebo) (mean difference (MD) 4.20, 95% confidence interval (CI) 2.15 to 6.25; MD 26.60, 95% CI 2.61 to 50.59, respectively). In these studies most of the adverse events related to the procedure or device for administration rather than the drug, such as swelling at the pump site. In one trial there were also eight serious adverse effects; these included difficulty swallowing and an epileptic seizure. The trial did not state if these occurred in the intervention group. At follow-up in both BoNT-A trials there was no evidence of a difference in pain between the trial arms among CP participants. The adverse events in the BoNT-A trials mostly involved those who received the intervention drug and involved seizures. Gastrointestinal problems were the most frequent adverse event in those who received alendronate. The trial investigating pamidronate found no evidence of a difference in pain compared to the control group. No adverse events were reported in this trial.

AUTHORS' CONCLUSIONS

Published, controlled evidence on the pharmacological interventions for pain in CYP with LLCs is limited. The evidence that is currently available evaluated pain largely as a secondary outcome and the drugs used were all adjuvants and not always commonly used in general paediatric palliative care for pain. Based on current data this systematic review is unable to determine the effects of pharmacological interventions for pain for CYP with LLCs. Future trials with larger populations should examine the effects of the drugs commonly used as analgesics; with the rising prevalence of many LLCs this becomes more necessary.

Childhood dystonias

OPINION STATEMENT

Dystonia is a movement disorder caused by diverse etiologies. Its treatment in children is particularly challenging due to the complexity of the development of the nervous system from birth to young adulthood. The treatment options of childhood dystonia include several oral pharmaceutical agents, botulinum toxin injections, and deep brain stimulation (DBS) therapy. The choice of drug therapy relies on the suspected etiology of the dystonia and the adverse effect profile of the drugs. Dystonic syndromes with known etiologies may require specific interventions, but most dystonias are treated by trying serially a handful of medications starting with those with the best risk/benefit profile. In conjunction to drug therapy, botulinum toxin injections may be used to target a problematic group dystonic muscles. The maximal botulinum toxin dose is limited by the weight of the child, therefore limiting the number of the muscles amenable to such treatment. When drugs and botulinum toxin injections fail to control the child's disabling dystonia, DBS therapy may be offered as a last remedy. Delivering optimal DBS therapy to children with dystonia requires a multidisciplinary team of experienced pediatric neurosurgeons, neurologists, and nurses to select adequate candidates, perform this delicate stereotactic procedure, and optimize DBS delivery. Even in the best hands, the response of childhood dystonia to DBS therapy varies greatly. Future therapy of childhood dystonia will parallel the advancement of knowledge of the pathophysiology of dystonic syndromes and the development of clinical and research tools for their study.

Responsiveness of the MD-childhood rating scale in dyskinetic cerebral palsy patients undergoing anticholinergic treatment

BACKGROUND

Movement Disorder-Childhood Rating Scale (MD-CRS) is a new tool for assessment of movement disorders during developmental age.

AIM

In this study we evaluated a cohort of 47 patients affected by dyskinetic cerebral palsy and treated with anticholinergic drug (trihexyphenidyl) over one year in order to verify the responsiveness of the new scale.

METHODS

The participants were divided into two groups according to their age (0-3 years; 4-18 years) and were evaluated using MD-CRS 0-3 or MD-CRS 4-18 at baseline, i.e., before starting pharmacological treatment (T0), after 6 (T1) and 12 months (T2) of treatment. Univariate repeated measures ANOVA with a Greenhouse-Geisser correction was performed to analyse the scale responsiveness for the three indexes (e.g., Index I, Index II and Global Index) in each group with time (T0, T1 and T2). In addition, Bonferroni test was performed to identify the source of significant differences among means.

RESULTS

Significant differences were found between time points (T1 vs T0, T2 vs. T0 and T2 vs. T1) in both scales for all indexes with the exception for T2 vs. T1 for Index II in both scales and for T2 vs. T1 for the Global Index in the older age group. There was not significant correlation between observed changes in the scores and age of children, either for MD-CRS 0-3 or MD-CRS 4-18.

CONCLUSIONS

Our results suggest that MD-CRS is a suitable tool to detect changes and could be used as outcome measure for clinical trials. Further studies will be necessary to prove the efficacy of trihexyphenidyl for dyskinetic cerebral palsy.

Special concerns in defining, studying, and treating dystonia in children

Dystonia is movement disorder with many diverse underlying etiologies. Some of those etiologies manifest at specific stages of development or at specific ages. Others may present early in life and evolve as the individual develops. The appearance of symptoms during a time of nervous system development poses special challenges to the neurologist. Normal functions change appearance, dysfunction may manifest in an age-dependent manner, and age-dependent differences in beneficial and toxic effects of treatments all introduce complexities to the process of diagnosis, functional assessment, and therapeutics. Consideration of these developmental differences is essential in assuring a universal definition of dystonia, and for developing valid and reliable assessment tools that can be compared across the lifespan, and more effective therapeutics. © 2013 Movement Disorder Society.

Intrathecal baclofen treatment in dystonic cerebral palsy: a randomized clinical trial: the IDYS trial

Background

Dystonic cerebral palsy is primarily caused by damage to the basal ganglia and central cortex. The daily care of these patients can be difficult due to dystonic movements. Intrathecal baclofen treatment is a potential treatment option for dystonia and has become common practice. Despite this widespread adoption, high quality evidence on the effects of intrathecal baclofen treatment on daily activities is lacking and prospective data are needed to judge the usefulness and indications for dystonic cerebral palsy. The primary aim of this study is to provide level one clinical evidence for the effects of intrathecal baclofen treatment on the level of activities and participation in dystonic cerebral palsy patients. Furthermore, we hope to identify clinical characteristics that will predict a beneficial effect of intrathecal baclofen in an individual patient.

Methods/Design

A double blind placebo-controlled multi-center randomized clinical trial will be performed in 30 children with dystonic cerebral palsy. Patients aged between 4 and 25 years old with a confirmed diagnosis of dystonic cerebral palsy, Gross Motor Functioning Classification System level IV or V, with lesions in the cerebral white matter, basal ganglia or central cortex and who are eligible for intrathecal baclofen treatment will be included. Group A will receive three months of continuous intrathecal baclofen treatment and group B will receive three months of placebo treatment, both via an implanted pump. After this three month period, all patients will receive intrathecal baclofen treatment, with a follow-up after nine months. The primary outcome measurement will be the effect on activities of and participation in daily life measured by Goal Attainment Scaling. Secondary outcome measurements on the level of body functions include dystonia, spasticity, pain, comfort and sleep-related breathing disorders. Side effects will be monitored and we will study whether patient characteristics influence outcome.

Discussion

The results of this study will provide data for evidence-based use of intrathecal baclofen in dystonic cerebral palsy.

Trial registration

Nederlands Trial Register, NTR3642

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

BACKGROUND

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Functional priorities in daily life for children and young people with dystonic movement disorders and their families

PURPOSE

This study aims to describe the most prevalent functional concerns of a group of young people with dystonia and their primary carers, and to explore the relationship between concerns, aetiology, severity of motor disability and manual ability.

METHOD

The Canadian Occupational Performance Measure (COPM) was completed with 57 children with dystonic movement disorders (65% males/35% females, mean 11.2 years (3.5-18.1)): 25% had primary dystonia, 75% secondary dystonia. Gross motor and manual function were classified using the Gross Motor Function Classification System (GMFCS) and the Manual Ability Classification System (MACS). COPM concerns were analysed with respect to aetiology and severity of motor disability.

RESULTS

Almost three quarters of the respondents were GMFCS/MACS IV-V. All respondents had at least one concern around self-care. Other concerns included access to assistive technology, pain, dressing activities, use of tools and social participation. The nature and presence of concerns did not statistically differ according to the severity of gross motor or manual function impairment, though qualitative differences were noted. No statistical difference was found in relation to aetiology.

INTERPRETATION

Children and young people with dystonia have common functional concerns and priorities independent of the cause of dystonia, gross motor severity or manual function ability.

Providing a primary care medical home for children and youth with cerebral palsy

All primary care providers will care for children with cerebral palsy in their practice. In addition to well-child and acute illness care, the role of the medical home in the management of these children includes diagnosis, planning for interventions, authorizing treatments, and follow-up. Optimizing health and well-being for children with cerebral palsy and their families entails family-centered care provided in the medical home; comanagement is the most common model. This report reviews the aspects of care specific to cerebral palsy that a medical home should provide beyond the routine health care needed by all children.

Effects of intrathecal baclofen on daily care in children with secondary generalized dystonia: a pilot study

AIM

Treatment options for dystonic cerebral palsy (CP) are limited. Our aims were to determine whether intrathecal baclofen (ITB) improves daily care, decreases dystonia and decreases pain in patients with dystonic CP.

METHODS

Patients received randomized blinded treatment with ITB or placebo. Scores on problems of daily care were recorded and dystonia, pain and comfort were assessed.

RESULTS

Four patients (three males, average age 12 years 6 months) were included (all Gross Motor Function Classification System level V). During the trial period problem scores and dystonia scores decreased in all four patients.

CONCLUSION

In this pilot study we report positive functional effects of ITB trial treatment in four patients with dystonic CP. A randomized trial with a larger cohort is needed to verify these results.

Milestones in dystonia

The last 25 years have seen remarkable advances in our understanding of the genetic etiologies of dystonia, new approaches into dissecting underlying pathophysiology, and independent progress in identifying effective treatments. In this review we highlight some of these advances, especially the genetic findings that have taken us from phenomenological to molecular-based diagnoses. Twenty DYT loci have been designated and 10 genes identified, all based on linkage analyses in families. Hand in hand with these genetic findings, neurophysiological and imaging techniques have been employed that have helped illuminate the similarities and differences among the various etiological dystonia subtypes. This knowledge is just beginning to yield new approaches to treatment including those based on DYT1 animal models. Despite the lag in identifying genetically based therapies, effective treatments, including impressive benefits from deep brain stimulation and botulinum toxin chemodenervation, have marked the last 25 years. The challenge ahead includes continued advancement into understanding dystonia's many underlying causes and associated pathology and using this knowledge to advance treatment including preventing genetic disease expression.

Os odontoideum as a rare but possible complication in children with dyskinetic cerebral palsy: a clinical and neuroradiologic study

The authors describe a 12-year-old boy with dyskinetic (athetoid-dystonic subtype) cerebral palsy and os odontoideum. Dystonic and choreoathetotic components in cerebral palsy are movement disorders that are difficult to treat and cause major disability. Dystonic posturing causes excessive flexion, extension, and rotation of the neck. Repetitive abnormal movements in patients with this type of cerebral palsy give rise to a higher incidence of pathologic conditions affecting the craniovertebral junction. Os odontoideum is one of these pathologies, and it represents a rare anomaly of the odontoid process. There are only a few reports describing os odontoideum in children with dyskinetic cerebral palsy. This clinical and neuroradiologic study focuses on the problem of atlantoaxial instability and os odontoideum in these forms of cerebral palsy, which is too often underestimated.

Trihexyphenidyl improves motor function in children with dystonic cerebral palsy: a retrospective analysis

There are conflicting reports regarding the efficacy of trihexyphenidyl, an anticholinergic drug, for treatment of dystonia in cerebral palsy. The author hypothesized that trihexyphenidyl may be more effective in specific subgroups and performed a retrospective analysis of 31 children (8.2 ± 5.8 years) with dystonia following treatment with high-dose trihexyphenidyl (>0.5 mg/kg/day). Main outcome measure was extent of motor improvement calculated according to the body areas affected. Most (21/31) caregivers reported improvement in 1 or more areas, mainly arm, hand, and oromotor function. Improvement was greater in children without spasticity (P = .02) and in those with higher cognitive function (P = .02). While a third of caregivers (10/31) reported tone reduction, and half (15/31) noted overall functional improvement. Side effects were transient, with the exception of hyperopia (n = 1), and occurred less frequently in children with a history of prematurity (P = .02). In summary, trihexyphenidyl is effective particularly in absence of spasticity and in children with higher cognitive abilities.

Diagnosis and management of glutaric aciduria type I--revised recommendations

Glutaric aciduria type I (synonym, glutaric acidemia type I) is a rare organic aciduria. Untreated patients characteristically develop dystonia during infancy resulting in a high morbidity and mortality. The neuropathological correlate is striatal injury which results from encephalopathic crises precipitated by infectious diseases, immunizations and surgery during a finite period of brain development, or develops insidiously without clinically apparent crises. Glutaric aciduria type I is caused by inherited deficiency of glutaryl-CoA dehydrogenase which is involved in the catabolic pathways of L-lysine, L-hydroxylysine and L-tryptophan. This defect gives rise to elevated glutaric acid, 3-hydroxyglutaric acid, glutaconic acid, and glutarylcarnitine which can be detected by gas chromatography/mass spectrometry (organic acids) or tandem mass spectrometry (acylcarnitines). Glutaric aciduria type I is included in the panel of diseases that are identified by expanded newborn screening in some countries. It has been shown that in the majority of neonatally diagnosed patients striatal injury can be prevented by combined metabolic treatment. Metabolic treatment that includes a low lysine diet, carnitine supplementation and intensified emergency treatment during acute episodes of intercurrent illness should be introduced and monitored by an experienced interdisciplinary team. However, initiation of treatment after the onset of symptoms is generally not effective in preventing permanent damage. Secondary dystonia is often difficult to treat, and the efficacy of available drugs cannot be predicted precisely in individual patients. The major aim of this revision is to re-evaluate the previous diagnostic and therapeutic recommendations for patients with this disease and incorporate new research findings into the guideline.

Use of trihexyphenidyl in children with cerebral palsy

A paucity of information exists regarding medications to treat dystonia in children with cerebral palsy. This study sought to review the benefits and tolerability of trihexyphenidyl in children with cerebral palsy, treated for dystonia or sialorrhea or both in a pediatric tertiary care hospital, through a retrospective chart review. In total, 101 patients (61 boys and 40 girls) were evaluated. The mean age at drug initiation was 7 years and 10 months (range, 1-18 years). The mean initial dose was 0.095 mg/kg/day. The dose was increased by 10-20% no sooner than every 2 weeks. The mean maximum dose reached was 0.55 mg/kg/day. Ninety-three patients (91%) tolerated the medication well, with a mean duration of treatment of 3 years and 7 months. Side effects occurred in 69% of subjects, the majority in patients aged ≥7 years, and soon after treatment initiation. Sixty-four percent continued the treatment at study end. Ninety-seven patients reported benefits, including reduction of dystonia in upper (59.4%) and lower (37.6%) extremities, sialorrhea (60.4%), and speech issues (24.7%). The majority of patients tolerated trihexyphenidyl well on a schedule of gradual dose increases, and almost all demonstrated improvements in dystonia or sialorrhea or both.

The adult with cerebral palsy

Advances in medical and surgical care over the past 20 years have resulted in children who formerly would have died at birth or infancy now surviving well into adulthood, many with permanent physical disabilities, including those caused by cerebral palsy. Inadequate medical and surgical diagnoses and intervention are prevalent in the adult cerebral palsy population. Decreased physical activity and participation in physical therapy and fitness programs, along with loss of strength, contractures, and pain are common factors in the loss of functional weight bearing, self-care, and daily performance over time. Increased awareness of these problems is needed by adult health care providers who provide care to these individuals and also by pediatric providers who may be able to intervene and prevent some of the long-term problems. Early identification and intervention in the child and younger adult remain the ideal in the pursuit of optimal musculoskeletal function and lifestyle throughout the adult years.

Upper limbs function after intrathecal baclofen therapy in children with secondary dystonia

BACKGROUND

Different studies show the efficacy of intrathecal baclofen therapy (ITB) in patients with secondary dystonia because of cerebral palsy. These studies only report improvements related to dystonia reduction; however, none of them have assessed whether such benefit is reflected in limb function. The purpose of our study is to determine whether the effects ITB therapy in patients with secondary dystonia to cerebral palsy, in addition to reducing dystonia, may also improve upper limb function.

METHODS

Eleven patients with secondary dystonia, classified as levels 3 and 4 of the Gross Motor Function Classification System, were treated with ITB. The mean age at implant was 11.3 (SD+/-3.02) years.Before treatment and 12 months after implant, the patients were evaluated by the Melbourne Assessment of Unilateral Upper Limb and the Barry Albright scale to assess upper limb function and dystonia, respectively.

RESULTS

We found a statistically significant improvement in both scales. The Melbourne scale total percentage score, for both limbs, increased in all patients (P<0.05). Dystonia assessed by the Barry Albright scale scale decreased significantly by 15% from baseline to 12 months follow-up (P<0.05).

CONCLUSIONS

In patients with secondary dystonia treated with ITB, functional improvement of the upper limbs was observed in addition to dystonia reduction. In patients with secondary dystonia, ITB is a treatment that aims to achieve a general reduction of dystonia; this study want to show the influence that this reduction has to functional ability of patient.

LEVEL OF EVIDENCE

Therapeutic study: level 4.

[Treatment of childhood dystonia]

Dystonia is not uncommon in childhood, but is clinically very heterogeneous. Therefore, introduction and follow-up of the treatment of dystonia in children are often a challenge for the physicians. Progresses in functional neurosurgery have open new fields in the treatment of dystonia in children, but it should be managed by a multidisciplinary team. This paper reviews the various therapeutic options available for childhood-onset dystonia, with a specific attention to dosage and side effects of the drugs regarding pediatric population according to the data of the literature. The rational strategy for therapeutic management of the various types of childhood dystonia is discussed.