Adverse events and health status following botulinum toxin type A injections in children with cerebral palsy

Short- medium- and long-term effects of botulinum toxin on upper limb spasticity in children with cerebral palsy: A meta-analysis of randomized controlled trials

BACKGROUND

Botulinum toxin (BTX) is an effective management method for spasticity in children with cerebral palsy (CP), but the short- medium- and long-term effects remain unclear.

OBJECTIVE

The primary objective was to quantify the effects of BTX injections on upper limb spasticity over time in children with CP. The secondary objective was to evaluate efficacy according to the International Classification of Functioning, Disability, and Health-Children & Youth version framework.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials that included control/comparison groups treated with a placebo or other treatments. We searched CINAHL, Embase, PubMed, Scopus, Web of Science, and PsycINFO from their inception to April 2024. The pooled mean difference (MD) or standard mean difference (SMD) with 95 % CI was calculated using a random effects model at the short-term (up to 3 months), medium-term (3 to 6 months), and long-term (over 6 months).

RESULTS

A total of 658 children with CP aged 1.8 to 19 years old in 12 eligible trials were involved. The primary outcome of the Melbourne Assessment percentile showed a significant increase in the medium- (MD = 2.63, 95 % CI 0.22 to 5.04, I² = 0 %) and long-term (MD = 4.72, 95 % CI 0.93 to 8.51, I² = 0 %) in favor of BTX. Pooled effects also showed that BTX significantly improved Modified Ashworth Scale scores in the short- (MD = -0.44, 95 % CI -0.88 to -0.01, I² = 88 %) and medium-term (MD = -0.20, 95 % CI -0.28 to -0.13, I² = 0 %), and individual goals and bimanual performance up to 6-months. No significantly higher risk of adverse events was observed with BTX.

CONCLUSIONS AND IMPLICATIONS

BTX injections sustainably improved the quality of affected upper limb function and temporarily improved individual goals and bimanual performance in children with CP. Our findings cautiously support a time interval of 3 to 6 months between BTX injections in the upper limbs of children with CP.

TRIAL REGISTRATION

This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO) (Registration ID: CRD42022323672).

Postoperative outcomes and stimulation responses for sectioned nerve roots during selective dorsal rhizotomy in cerebral palsy

BACKGROUND

Cerebral palsy (CP) is the most cause of motor dysfunction in children. Selective dorsal rhizotomy (SDR) plays a major role in long term spasticity control. However, limited data exists on the effect of SDR on postoperative spasticity treatment requirements and supraspinal effects, and the stimulation responses of dorsal nerve roots in those with CP.

METHODS

The current study included the outcome for 35 individuals undergoing SDR for motor functional outcome, spasticity, baclofen dose changes, botulinum toxin injection frequency, and spasticity related orthopedic procedures. We also report on the stimulation responses in 112 individuals who underwent SDR at our institution.

RESULTS

There was a significant difference in gross motor function measures (GMFM)-66 scores at last follow up that remained present when considering only ambulatory children but not with non-ambulatory children. Ashworth scores were significantly decreased for both upper and lower extremities after SDR at all follow up points. There was a significant decrease in Baclofen dose and botulinum toxin injections requirements after SDR, but no significant difference in the need for orthopedic intervention. A total of 5502 dorsal nerve roots were tested showing a decrease in stimulation intensity and increase in grade on the right side and for descending lumbosacral levels.

CONCLUSIONS

SDR improves gross motor scores during short term follow up but has additional benefits in decreasing baclofen dosing and botulinum toxin injections requirements after surgery. They stimulation responses of sectioned dorsal nerve roots adds to the limited available data and our understanding of the pathological changes that occur in CP.

Safety of botulinum toxin injections in children less than one year old: A retrospective chart review

PURPOSE

Infants can have muscle hypertonia due to cerebral palsy, muscle strength imbalances due to brachial plexus palsy, refractory clubfoot, and torticollis. These muscle problems can cause significant development impairments. A child with severe sialorrhea and dysphagia from leukodystrophy can aspirate, causing respiratory problems. Botulinum toxin (BoNT) injections can improve these conditions but may lead to adverse effects from the toxin spreading to non-targeted muscles, potentially impacting breathing, swallowing, and overall strength. This is particularly concerning in infants. This study assessed the safety of BoNT injections in children less than one year of age.

METHODS

This was a retrospective cohort study.

RESULTS

Forty-seven patients (22 male, 25 female) received BoNT injections before one year of age (three to 12 months). Thirty-seven received one round of injections and 10 were injected on multiple occasions. Forty-five received onabotulinumtoxinA (15-100 units [U], 1.9-15.2 U/kg), one received abobotulinumtoxinA (70 U, 9.0 U/kg), and one received incobotulinumtoxinA (25 U, 3.5 U/kg). Lower extremities were treated in 15 patients, upper extremities in 38, the sternocleidomastoid in two, and the salivary glands in one. Forty-five patients had no reported complications. One experienced transient fever, vomiting, and diarrhea. The parent of another reported subjective weakness in one muscle.

CONCLUSION

BoNT injections in children less than one year of age appear to be safe.

Adverse effects following botulinum toxin A injections in children with cerebral palsy

The study aimed to analyze the adverse events associated with botulinum toxin A (BoNT-A) injections in children with cerebral palsy (CP). The literature search was completed using the Medline, PubMed, Google Scholar, Scopus, and Cochrane Library databases from the earliest date possible up to December 2021. Search terms included 'botulinum toxin', 'cerebral palsy', 'spasticity', 'adverse effects', 'side effects', 'undesirable effects', 'complications', 'lower limb', 'upper limb', and 'children' including combinations of index and free-text terms. Fifty-five studies were included in the study. Data on 6333 pediatric patients and more than 14 080 BoNT-A injections were collected. Respiratory symptoms and respiratory tract infections were the most frequently registered adverse events (AEs). Other common AEs included procedural/focal AEs, flu-like symptoms, and asthenia. Sentinel events including four cases of death were reported. AEs were more frequent and severe in high-dose patients; however, the capacity of BoNT-A to spread systemically remains unclear. Since severe adverse events are not common, further research is needed to collect more definitive clinical and homogeneous data to support the findings of the present research and clarify the safety profile of BoNT-A, especially regarding the incidence of respiratory issues and complications in GMFCS IV or V patients.

Adverse events after different forms of botulinum neurotoxin A injections in children with cerebral palsy: An 8-year retrospective study

AIM

To compare the risks of adverse events 3 months after Onabotulinumtoxin-A and Lanbotulinumtoxin-A injections in children with cerebral palsy (CP) and to identify risk factors and associations.

METHOD

A total of 1037 children (682 males, 355 females; mean age 5 years 2 months [SD 3 years]; age range 2 years-17 years 10 months) with CP underwent 1013 Onabotulinumtoxin-A injections and 418 Lanbotulinumtoxin-A injections from 2012 to 2021. Information was recorded in a purpose-built database.

RESULTS

The adverse event rates of Onabotulinumtoxin-A and Lanbotulinumtoxin-A were reported as 13.92% and 11.96% respectively. Most adverse events were mild and self-limiting. Children in Gross Motor Function Classification System (GMFCS) levels IV to V had a higher risk of adverse events than those in GMFCS levels I to III (odds ratio [OR] [95% confidence interval {CI}] = 3.65 [1.56, 5.40], p < 0.01). The history of recent illness and higher dose increased the likelihood of adverse events (OR [95% CI] = 2.00 [1.55, 3.00] and 2.20 [1.53, 3.07] respectively, p < 0.01). Sex, age, and the number of injections had no significant effect on adverse event rates (p > 0.05). The incidence of upper respiratory tract infection and lower respiratory tract infection after injections was weakly correlated with the incidence before injections (r = 0.36 and r = 0.27 respectively, p < 0.01).

INTERPRETATION

Occurrence of adverse events was similar between Onabotulinumtoxin-A and Lanbotulinumtoxin-A in children with CP. Dose, GMFCS level, and health background were risk factors.

WHAT THIS PAPER ADDS

The prevalence of adverse events was similar between Onabotulinumtoxin-A and Lanbotulinumtoxin-A in children with cerebral palsy (CP). The prevalence of adverse events increased with the severity of CP and the injected dose. Sex, age, and number of injections had no significant effect on the prevalence of adverse events.

Upper Limb Onabotulinumtoxin A Injections in Children Under 2 Years with Cerebral Palsy: A Retrospective Chart Review

Aim: To report on the safety of using Onabotulinumtoxin A (OnaA) in the upper limb(s) of children <2 years of age with cerebral palsy and to describe a proactive clinical model of care in the management of upper limb impairment in children with cerebral palsy. Methods and procedures: Retrospective chart audit of 65 infants aged 13-23 months (mean 18.69) who received upper limb OnaA injections. Administration procedures, trends in muscle selection, and adverse events were examined. Results: Adverse events were reported in 6 (4%) of the 65 children. Across the study period, muscles that control thumb and forearm movements were most commonly injected. The number of OnaA injections to subscapularis and flexor digitorum profundus increased over this period. Conclusions and implications: OnaA is a safe treatment option for the short-term management of focal upper limb muscle overactivity in children under 2 years of age with cerebral palsy. In line with existing evidence, OnaA should always be considered as an adjunct to evidence-based therapy.

Current Australian clinical practice in use of botulinum toxin-A to manage paediatric hypertonicity

AIM

To describe current rehabilitation paediatricians' use of intramuscular botulinum toxin-A (BoNT-A) to manage hypertonicity.

METHODS

Cross-sectional survey.

RESULTS

In late 2019, 32 of the 35 identified Australian rehabilitation paediatricians who use BoNT-A to manage paediatric hypertonicity completed the survey. Annually, they administer just over 3750 courses of BoNT-A to manage hypertonicity with a mean of 11 years of clinical experience. Sedation was used by all but 1 clinician who used a number of other strategies during the procedure. Mean (and median) maximum dose of OnabotulinumtoxinA (Botox) was 400 Units (range 300-450 Units). Only three clinicians indicated that they used AbobotulinumtoxinA (Dysport) - the other BoNT-A preparation approved for children available in Australia; analysis of its use was not performed. Dose modifications were made by clinicians according to a patient's response to a previous course of BoNT-A (88% of respondents); patient experience of a previous adverse event (78%); history of aspiration or dysphagia (65 and 63%, respectively); and the presence of dystonia; and where the patient was GMFCS level V (53% each). Intervals between courses ranged from 3 to 24 months with the variation due to clinical circumstances.

CONCLUSION

Clinical practice in BoNT-A management of paediatric hypertonicity was largely consistent in regard to maximum doses of OnabotulinumtoxinA (Botox) used. Dose modification and time between injection courses varied according to individual clinical presentation. Procedural sedation was used extensively.

Exploring the role of botulinum toxin in critical care

INTRODUCTION

Botulinum neurotoxin (BoNT) is one of the most potent and extensively studied neurotoxins with clinical applications across several different medical specialties. This review article explores the latest evidence for therapeutic applications of BoNT in patients receiving critical management in an intensive care unit (ICU).

AREAS COVERED

The authors did a literature search in PubMed, Google Scholar, and Texas Medical Center Library database for studies describing the use of BoNT in a critical care setting. They extracted information on study design, patient selection, methodology, and results of relevant studies. Based on initial identification of 85 studies and after conducting screening, the authors identified 61 studies to be included in this review. In an ICU setting, BoNT has been used for several neurological and non-neurological indications. However, the supporting evidence is mostly limited to small observational studies.

EXPERT OPINION

The use of BoNT in this setting is largely underutilized due to paucity of well-designed clinical trials and financial barriers. Further research is needed to provide evidence for the safety and efficacy of BoNT and to optimize the dosing and injection techniques for various conditions encountered in this setting.

[Multilevel botulinum toxin treatment in severe spastic forms of cerebral palsy (GMFCS IV-V)]

OBJECTIVE

To evaluate the most typical target muscles and dosages for the first and repeated botulinum toxin A (BTA) injections in cerebral palsy (CP) patients with severe motor deficit - GMFCS IV-V.

MATERIAL AND METHODS

A retrospective analysis of 677 protocols of the first and repeated Abobotulinumtoxin A (AboA) injections in 333 patients with CP GMFCS IV and V, aged 1 to 18 years, was carried out.

RESULTS

Ninety-seven percent of patients received multilevel injections. In the lower extremities the most typical target muscles were: m.gracilis - 221 (66.4%) patients, hip adductors - 164 (49.2%), medial hamstring - 144 (43.2%). In the upper extremities the most typical muscles were: m.pronator teres - 237 (71.2%) patients, m.biceps brachii+m.brachialis - 197 (59.2%). The total dosages of AboA and dosages for every target muscle were calculated. Several patients required high dosages (more than 30 U/kg of AboA). Higher dosages per kg were used in younger children and for repeated injections. The age-related evolution of spastic patterns was described. Adverse events were observed in 36 cases (5.3% of all injections).

CONCLUSION

The majority of patients with GMFCS IV-V required multilevel BTA injections in high dosages, especially in young age. Described selection of target muscles and dosages of AboA could be taken into account as a practical experience and reference for the BTA therapy in GMFCS IV-V patients.

Botulinum Toxin Type A injections for pediatric spasticity: Keeping our patients informed and practices safe

Serious adverse events (serious AEs) following the therapeutic use of Botulinum Toxin Type A (BoNT-A) are infrequent. Children with pediatric spasticity often have comorbidities that can cloud causation around an adverse event (AE). If a serious AE occurs, clear documentation of information sharing and informed consent as well as the provider-patient relationship are critical to minimizing litigation risks. Reviewing the litigation that has occurred following BoNT-A for pediatric spasticity can offer insight into how providers' perspectives regarding this intervention may differ from those of the public who might serve as jurists. This article offers suggestions for content sharing during the consent process to optimize patient understanding about potential adverse events.

A prospective study investigating gross motor function of children with cerebral palsy and GMFCS level II after long-term Botulinum toxin type A use

BACKGROUND

The aim of this study is to contribute to the knowledge base on the long-term outcomes of evidence-based medical interventions used to improve gross motor function in children and adolescents with Cerebral Palsy.

METHOD

Prospective cohort study of children with Cerebral Palsy in the birth years 2000-2009 attending a tertiary level service for children with Cerebral Palsy who's first recorded Gross Motor Function Classification System level was II.

RESULTS

A total of 40 children were eligible for the study, of whom 28 (72.7%) enrolled. The Botulinum toxin A treatment for this cohort, (median and interquartile ranges) were: total number of lower limb Botulinum toxin A injections 11 (6.7, 5.5); total dose of Botulinum Toxin A per lower limb treatment 6.95 u/kg (4.5, 11); and dose of Botulinum Toxin u/kg/muscle 2.95 (2.2, 4). For all 28 subjects there was a median of 15 (8.5 to 22) Gross Motor Function Classification System level recordings: six of the 28 children (21.4%) improved from level II to level I, the remaining 22 children remained stable at level II (78.6%). In this highly treated population, the average 66 item Gross Motor Function Measure score for the 22 children in level II was 72.55, which is consistent with the mean of 68.5 reported in the original Ontario cohort.

CONCLUSION

This cohort study has confirmed that children with Cerebral Palsy, Gross Motor Function level II treated at a young age with repeated doses of Botulinum Toxin A within an integrated comprehensive service, maintain or improve their functional motor level at a later age.

A pragmatic approach to Botulinum Toxin safety

Botulinum Toxin (BoNT) is widely used to treat hypertonia in pediatric patients. Although serious adverse events (AEs) occur infrequently, they can lead to significant patient morbidity and mortality. This paper will discuss potential safety risks that may affect outcomes, medical comorbidities, medication dosing, targeting techniques, and muscle morphology. It is the responsibility of the physician to discuss risks and benefits regarding the use of BoNT and mitigate risks of AEs while maximizing the effectiveness of the medication.

Botulinum toxin and surgical intervention in children and adolescents with cerebral palsy: who, when and why do we treat?

INTRODUCTION

This audit aimed to increase understanding of the long-term outcomes of evidence-based medical and surgical interventions to improve gross motor function in children and adolescents with Cerebral Palsy.

METHODS

Retrospective audit of a birth cohort (2000-2009) attending a tertiary service in Western Australia.

RESULTS

The cohort comprises 771 patients aged 8 to 17 years. Percentage of children receiving no Botulinum Toxin treatments in each Gross Motor Functional Classification System level was: I: 40%, II: 26%, III: 33%, IV: 28% and V: 46%. Of the total cohort, 53% of children received 4 or less Botulinum Toxin treatments and 3.7% received more than 20 treatments. Statistically significant difference in the rate of use of Botulinum Toxin pre and post-surgery (p < 0.001) was documented. Children levels IV and V had 5 times the odds of surgery compared to children levels I-III (Odds Ratio 5.2, 95% Confidence Interval 3.5 to 7.8, p < 0.001). For 578 (75%) of participants the last recorded level was the same as the first.

CONCLUSION

This audit documents medical intervention by age and Gross Motor Functional Classification System level in a large cohort of children with cerebral palsy over time and confirms stability of the level in the majority.IMPLICATIONS FOR REHABILITATIONThe information from this audit may be of use in discussions with families regarding the timing and use of Botulinum toxin and surgical intervention for motor function in children and adolescents with Cerebral Palsy.Long term use of Botulinum Toxin within an integrated evidence-based clinical program is not associated with loss of gross motor function in the long term as evidenced by the maintenance of Gross Motor Functional Classification System stability.

Botulinum Toxin in the Management of Children with Cerebral Palsy

During the past 25 years, botulinum toxin type A (BoNT-A) has become the most widely used medical intervention in children with cerebral palsy. In this review we consider the gaps in our knowledge in the use of BoNT-A and reasons why muscle morphology and function in children with cerebral palsy are impaired. We review limitations in our knowledge regarding the mechanisms underlying the development of contractures and the difficulty in preventing them. It is clear from this review that injection of BoNT-A in the large muscles of both the upper and lower limbs of children with cerebral palsy will result in a predictable decrease in muscle activity, which is usually reported as a reduction in spasticity, for between 3 and 6 months. These changes are noted by the use of clinical tools such as the Modified Ashworth Scale and the Modified Tardieu Scale. Decreased muscle over-activity usually results in improved range of motion in distal joints. Injection of the gastrocnemius muscle for toe-walking in a child with hemiplegia or diplegia usually has the effect of increasing the passive range of dorsiflexion at the ankle. In our review, we found that this may result in a measurable improvement in gait by the use of observational gait scales or gait analysis, in some children. However, improvements in gait function are not always achieved and are small in magnitude and short lived. We found that some of the differences in outcomes in clinical trials may relate to the use of adjunctive interventions such as serial casting, orthoses, night splints and intensive therapy. We note that the majority of clinical trials of the use of BoNT-A in children with cerebral palsy have focussed on a single injection cycle and this is insufficient to understand the balance between benefit and harm. Most outcomes were reported in terms of changes in muscle tone and there were fewer studies with robust methodology that reported improvements in function. Changes in the domains of activities and participation have rarely been reported in studies to date. There were no clinical reviews to date that consider the findings of studies in human volunteers and in experimental animals and their relevance to clinical protocols. In this review we found that studies in human volunteers and in experimental animals show muscle atrophy after an injection of BoNT-A for at least 12 months. Muscle atrophy was accompanied by loss of contractile elements in muscle and replacement with fat and connective tissue. It is not currently known if these changes, mediated at a molecular level, are reversible. We conclude that there is a need to revise clinical protocols by using BoNT-A more thoughtfully, less frequently and with greatly enhanced monitoring of the effects on injected muscle for both short-term and long-term benefits and harms.

Systemic adverse events after botulinum neurotoxin A injections in children with cerebral palsy

AIM

To identify factors that increase the likelihood of systemic adverse events after botulinum neurotoxin A (BoNT-A) injections in children with cerebral palsy (CP).

METHOD

A prospective observational study of patients attending a BoNT-A clinic at a tertiary paediatric hospital (2010-2014). Occurrences of systemic adverse events, defined as lower respiratory tract illnesses, generalized weakness, dysphagia, and death were determined at follow-up. The relationship between systemic adverse events and eight preinjection variables (age, Gross Motor Function Classification System [GMFCS] level, history of dysphagia, gastrostomy, aspiration pneumonia, recent history of illness, BoNT-A dose, and type of sedation) were examined using univariable and multivariable logistic regression with generalized estimating equations methods.

RESULTS

In total 591 children underwent 2219 injection episodes with follow-up in 2158 (97%) cases. Systemic adverse events were reported in 77 (3.6%) injection episodes. Univariable analysis suggested that GMFCS levels IV and V, a history of dysphagia, gastrostomy, aspiration pneumonia, and increasing BoNT-A dose increase the likelihood of systemic adverse events. In multivariable analysis, a history of dysphagia (odds ratio [OR] 3.42) and/or aspiration pneumonia (OR 2.31) remained associated with increased likelihood of systemic adverse events.

INTERPRETATION

A history of dysphagia and/or aspiration pneumonia are the factors that most increase the likelihood of systemic adverse events after BoNT-A.

WHAT THIS PAPER ADDS

Systemic adverse events occur in 3.6% of botulinum neurotoxin A (BoNT-A) injection episodes. Dysphagia and/or aspiration pneumonia are associated with increased likelihood of systemic adverse events. Multivariable models showed no evidence of association between Gross Motor Function Classification System and systemic adverse events. Multivariable models showed no evidence of association between BoNT-A dose and systemic adverse events.

Severity of cerebral palsy and likelihood of adverse events after botulinum toxin A injections

AIM

To determine the incidence of common adverse events after botulinum toxin A (BoNT-A) injections in children with cerebral palsy (CP) and to identify whether the severity of CP influences the incidence of adverse events.

METHOD

This was an observational study of patients attending a BoNT-A clinic at a tertiary paediatric hospital (2010-2014). Data examined included procedural adverse events at the time of injection and at follow-up. Systemic adverse events were defined as lower respiratory tract illnesses, generalized weakness, dysphagia, and death. Severity of CP was categorized by the Gross Motor Function Classification System (GMFCS). The relationships between GMFCS and adverse events were analysed using negative binomial regression models.

RESULTS

In total, 591 children underwent 2219 injection episodes. Adverse events were reported during the procedure (130 [6%] injection episodes) and at follow-up (492 [22%] injection episodes). There were significantly increased rates of systemic adverse events in injection episodes involving children in GMFCS level IV (incidence rate ratio [IRR] 3.92 [95% confidence interval] 1.45-10.57]) and GMFCS level V (IRR 7.37 [95% confidence interval 2.90-18.73]; p<0.001).

INTERPRETATION

Adverse events after BoNT-A injections are common but mostly mild and self-limiting. Children in GMFCS levels IV and V are at increased risk of systemic adverse events. The relationship between CP severity and BoNT-A adverse events is complex and further research is required to better understand this relationship.

WHAT THIS PAPER ADDS

Adverse events reported at the time of botulinum toxin A injection occurred in 6% of injection episodes. Adverse events were reported at follow-up in 22% of injection episodes. Children in Gross Motor Function Classification System (GMFCS) levels IV and V have increased rates of systemic adverse events. Children in GMFCS levels IV and V report less local weakness and pain.

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.

Injection of high dose botulinum-toxin A leads to impaired skeletal muscle function and damage of the fibrilar and non-fibrilar structures

Botulinum-toxin A (BoNT/A) is used for a wide range of conditions. Intramuscular administration of BoNT/A inhibits the release of acetylcholine at the neuromuscular junction from presynaptic motor neurons causing muscle-paralysis. The aim of the present study was to investigate the effect of high dose intramuscular BoNT/A injections (6 UI = 60 pg) on muscle tissue. The gait pattern of the rats was significantly affected 3 weeks after BoNT/A injection. The ankle joint rotated externally, the rats became flat footed, and the stride length decreased after BoNT/A injection. Additionally, there was clear evidence of microstructural changes on the tissue level by as evidenced by 3D imaging of the muscles by Synchrotron Radiation X-ray Tomographic Microscopy (SRXTM). Both the fibrillar and the non-fibrillar tissues were affected. The volume fraction of fibrillary tissue was reduced significantly and the non-fibrillar tissue increased. This was accompanied by a loss of the linear structure of the muscle tissue. Furthermore, gene expression analysis showed a significant upregulation of COL1A1, MMP-2, TGF-b1, IL-6, MHCIIA and MHCIIx in the BoNT/A injected leg, while MHVIIB was significantly downregulated.

IN CONCLUSION

The present study reveals that high dose intramuscular BoNT/A injections cause microstructural damage of the muscle tissue, which contributes to impaired gait.

Establishing a Multidisciplinary Approach to the Management of Neurologic Disease Affecting the Urinary Tract

Neurologic diseases often affect the urinary tract and may be congential or acquired. The progressive nature of many neurologic diseases necessitates routine surveillance and treatment with a multidisciplinary approach. Urologic treatments may interact with pharmacologic or procedural interventions planned by other specialists, mandating close coordination of care and communication among providers. Primary care and nursing often can serve as the quarterbacks of the multidisciplinary team by identifying when a slowly progressive condition warrants further investigation and management by specialists.

Cerebral palsy dysphagia: a systematic review

ABSTRACT Cerebral palsy (CP) encompasses a group of definitive and non-progressive conditions, with a non-progressive character and its installation in neonatal period. Motor disorders caused by CP may lead to changes in swallowing, resulting in limitations in the activities that are attributed to non-progressive disorders that do not reach the developing child's brain. This article reviews the clinical aspects of dysphagia in CP and the treatments in the area. Only papers published in the period from 2009 to 2017 were considered, using a methodological strategy for electronic search in the databases SciELO-Brazil, Lilacs and Medline/Pubmed. The present research analyzed 24 articles, regarding the year of publication, sample and instruments used, verifying that Speech Therapists and other staff involved in the improvement and rehabilitation of cognitive functions have provided better rehabilitation conditions, despite the need for more therapy and diagnostic studies.

Botulinum Toxin Injection for Internal Rotation Contractures in Brachial Plexus Birth Palsy. A Minimum 5-Year Prospective Observational Study

BACKGROUND

Brachial plexus birth palsy is frequently associated with internal rotation contractures of the shoulder as a result of muscle imbalance. The purpose of this study is to assess the effect of botulinum toxin A (BTX-A) injection in the subscapular (SC) muscle on external rotation and the need for tendon transfer for external rotation of the shoulder.

METHODS

A prospective comparative study was performed including 15 consecutive patients treated with BTX-A and a historic control group of 67 patients with mean age 30 months (SD 10). The BTX-A injection (2 IU/kg body weight) was performed immediately following MRI under general anesthesia in the SC muscle. Passive external rotation, the need for tendon transfer surgery, glenohumeral deformity, and muscle degeneration were evaluated. The hazard ratio for no relapse of internal rotation contracture after BTX-A injection compared with no BTX-A injection was calculated.

RESULTS

In the BTX-A group, the passive external rotation in adduction increased from -1 degree (95% CI, -10 to 8) to 32 degrees (95% CI, 17-46) at 3 months and 6 patients were indicated for surgery compared with a decline from -2 degrees (95% CI, -7 to 3) to -11 degrees (95% CI, -17 to -6) in the control group with 66 indications for surgery. At 5 years of follow-up, 10 patients in the BTX-A group were indicated for surgery with a hazard ratio of 4.0 (95% CI, 1.9 to 8.4).

CONCLUSIONS

BTX-A injection in the SC muscle of brachial plexus birth palsy patients can reduce internal rotation contractures and subsequently the need for tendon transfer surgery. At 5 years of follow-up a relapse was seen in 67% of the patients treated with BTX-A. Because at MRI less SC degeneration was found in the good responders on BTX-A treatment, this group seems to be the best target group. Further research is needed on patient selection for BTX-A injection including glenohumeral deformity, SC degeneration, as well as doses of BTX-A to be used.

LEVEL OF EVIDENCE

Level II-prospective comparative study.

Negative effects of submandibular botulinum neurotoxin A injections on oral motor function in children with drooling due to central nervous system disorders

AIM

The aims of this study were: (1) to determine the incidence and nature of adverse effects on oral motor function after first injections of botulinum neurotoxin A (BoNT-A) in submandibular glands for excessive drooling in children with central nervous system disorders; and (2) to identify independent predictors of these adverse effects.

METHOD

A cohort study involved 209 children (123 males, 86 females, aged 4-27y, median 8y 4mo), who received submandibular BoNT-A injections for drooling. Adverse effects were categorized into swallowing, eating, drinking, articulation, and other problems. Univariable logistic regression was used to study differences in patients with and without adverse effects. Possible predictors were identified using multivariable logistic regression.

RESULTS

Transient adverse effects occurred in 33% of the 209 BoNT-A treatments. Almost 80% of these were mild, versus 8.7% severe. Approximately 54% of the adverse effects spontaneously resolved within 4 weeks; 3% still existed after 32 weeks. A diagnosis of cerebral palsy, higher range of BoNT-A dosage, and a pre-treatment drooling quotient <18% were found to be independent predictors of adverse effects.

INTERPRETATION

Before using submandibular BoNT-A injections for drooling, potential adverse effects should be discussed. Oral motor function needs to be monitored, because existing dysphagia may be worsened. The identified clinical predictors could be helpful to optimize patient selection.

Adverse drug reactions of botulinum neurotoxin type A in children with cerebral palsy: a pharmaco-epidemiological study in VigiBase

AIM

The aim of this study was to assess the risk of adverse drug reactions (ADRs) with botulinum neurotoxin type A (BoNT-A) in children with cerebral palsy (CP) using the World Health Organization global individual case safety report (ICSR) database, VigiBase.

METHOD

We extracted all children ICSRs for ADRs with BoNT-A used as anti-spastic drug in CP recorded between 1995 and 2015 in VigiBase. We also performed a case/non-case method (disproportionality analysis) to assess the link between exposure to BoNT-A and each ADR of interest in children and adults, calculating reporting odds ratios (RORs).

RESULTS

In VigiBase, 162 ICSRs were registered. They involved mainly males (n=95, 59%) and mean (SD) age was 7 years 11 months (4y 4mo). The most frequent ADR was dysphagia (27 ICSRs, 17%) followed by asthenia and muscular weakness (25 ICSRs each, 16%). Nineteen ICSRs (12%) were lethal. There was a significant association between BoNT-A and death in children (ROR=11.1 95%, confidence interval [CI] 7.0-17.7) but not in adults.

INTERPRETATION

In children with CP, most ADRs seem to be linked to a systemic spread of BoNT-A. Our study suggests a higher risk of ADRs with BoNT-A in children than in adults.

No Decrease in Muscle Strength after Botulinum Neurotoxin-A Injection in Children with Cerebral Palsy

Spasticity and muscle weakness is common in children with cerebral palsy (CP). Spasticity can be treated with botulinum neurotoxin-A (BoNT-A), but this drug has also been reported to induce muscle weakness. Our purpose was to describe the effect on muscle strength in the lower extremities after BoNT-A injections in children with CP. A secondary aim was to relate the effect of BoNT-A to gait pattern and range of motion. Twenty children with spastic CP were included in the study, 8 girls and 12 boys (mean age 7.7 years). All were able to walk without support, but with increased muscle tone interfering with motor function and gait pattern. Sixteen children had unilateral spastic CP and four bilateral spastic CP. Twenty-four legs received injections with BoNT-A in the plantar flexor muscles. The children were tested before treatment, around 6 weeks after at the peak effect of BoNT-A, and at 6 months after treatment, with measurement of muscle strength, gait analysis, and range of motion. There were no differences in muscle strength in plantar flexors of treated legs at peak effect compared to baseline. Six months after treatment, there was still no change in untreated plantar flexor muscles, but an increasing trend in plantar flexor strength in legs treated with BoNT-A. Parents reported positive effects in all children, graded as: small in three children, moderate in eight, and large in nine children. The gait analysis showed a small improvement in knee extension at initial contact, and there was a small increase in passive range of motion for ankle dorsiflexion. Two children had a period with transient weakness and pain. We found that voluntary force production in plantar flexor muscles did not decrease after BoNT-A, instead there was a trend to increased muscle strength at follow-up. The increase may be explained as an effect of the blocking of involuntary nerve impulses, leading to an opportunity to using and training the muscles with voluntary control. Adequate muscle strength is important for maintaining the ability to walk and knowledge of how a treatment affects muscle strength is useful when selecting interventions.

Safety profile of incobotulinum toxin A [Xeomin(®)] in gastrocnemious muscles injections in children with cerebral palsy: Randomized double-blind clinical trial

BACKGROUND

The only two preparations of botulinum toxin A for which there are published evidences of efficacy in children with cerebral palsy are onabotulinum toxin A (Botox(®)) and abobotulinum toxin A (Dyport(®)); these toxins should be considered generally safe and appropriate in the treatment for localized upper and lower limb spasticity.

AIMS

To establish the safety profile of incobotulinum toxin A (Xeomin(®)) in children with cerebral palsy and muscle spasticity.

METHODS

Randomized double-blind controlled trial that involved the recruitment of children of both sexes with spastic hemiplegia or diplegia in cerebral palsy, aged between 3 and 18 years. Children were randomized to either the study group (SG, incobotulinum toxin A) or the control group (CG, onabotulinum toxin A) both to be injected with 5units/kg on gastrocnemius (medialis and lateralis) muscles. The occurrence of adverse events at baseline, after 48 h, 10 days and 3 months was recorded by the caregivers in a checklist that listed both common and uncommon side effects.

RESULTS

35 patients were treated (CG = 18; SG = 17); the 2 groups were well balanced regarding demographics and anthropometry characteristics. At least 1 adverse event occurred in 49% of patients within first 2 days, 46% between 2 and 10 days, and 12% between 10 and 90 days. All the reported events were minor; no serious adverse event was recorded. Fatigue was the most frequent complaint. There was no significant difference in frequency and type of events between the 2 groups.

CONCLUSION

Incobotulinum toxin A and onabotulinum toxin A share similar profile of safety in the treatment of lower limb spasticity in CP children.

Treatment with botulinum toxin in children with cerebral palsy: a qualitative study of parents' experiences

BACKGROUND

In children with cerebral palsy everyday movements such as walking, standing and using one's hands can be difficult to perform because of spasticity. Botulinum neurotoxin type A (BoNT-A) are often used to reduce spasticity. The aim of this study was to describe how parents of children with cerebral palsy experienced the child's treatment with BoNT-A, how the child was affected by the treatment and how spasticity affected the child.

METHODS

A qualitative study in which 15 parents of children (6-13 years old) with cerebral palsy were interviewed about their experiences of the BoNT-A treatment. The children had received several BoNT-A treatments. An interview guide was used with topics: the child's functions before and after the treatment, the outcomes of the treatment and how they valued the BoNT-A treatment. Content analysis was used to analyse the interviews.

RESULTS

The analyses resulted in two themes: 'When softness comes and goes' and 'Both want and do not want'. The reduction of spasticity - softness - was described to promote motor functions, and facilitate the next step in motor development. The children were described as being more active out of their own initiative and having a happier mood. Spasticity, described as stiffness, was described to make walking more strenuous as well as interfering with activities. The BoNT-A injection procedure was perceived as troublesome and painful for the child, and sometimes traumatic for both children and parents.

CONCLUSIONS

Treatment with BoNT-A was described as facilitating motor development and activity. The children's and the parents' negative experiences of the injection procedure should be addressed.

Muscle histopathology in children with spastic cerebral palsy receiving botulinum toxin type A

INTRODUCTION

Botulinum toxin A (BoNTA) is routine treatment for hypertonicity in children with cerebral palsy (CP).

METHODS

This single-blind, prospective, cross-sectional study of 10 participants (mean age 11 years 7 months) was done to determine the relationship between muscle histopathology and BoNTA in treated medial gastrocnemius muscle of children with CP. Open muscle biopsies were taken from medial gastrocnemius muscle and vastus lateralis (control) during orthopedic surgery.

RESULTS

Neurogenic atrophy in the medial gastrocnemius was seen in 6 participants between 4 months and 3 years post-BoNTA. Type 1 fiber loss with type 2 fiber predominance was significantly related to the number of BoNTA injections (r = 0.89, P < 0.001).

CONCLUSIONS

The impact of these changes in muscle morphology on muscle function in CP is not clear. It is important to consider rotating muscle selection or injection sites within the muscle or allowing longer time between injections.

Safety of Botulinum Toxin Type A for Children With Nonambulatory Cerebral Palsy

OBJECTIVE

To determine safety of intramuscular botulinum toxin A (BoNT-A) injections to reduce spasticity and improve care and comfort of nonambulatory children with cerebral palsy (CP).

METHODS

Nonambulatory children with CP were randomly allocated to receive either BoNT-A (n = 23) or sham procedure (n = 18) in Cycle 1. In Cycle 2, the BoNT-A group received a second episode of BoNT-A (n = 20) and sham group received their first episode of BoNT-A (n = 17). A pediatric rehabilitation specialist masked to group allocation graded each adverse event (AE) according to system, severity (mild, moderate, serious, sentinel) and causality (unlikely/unrelated; possible; probable/definite).

RESULTS

There was no difference for all moderate/serious AEs between the BoNT-A and sham/control groups in either Cycle 1 (incident rate ratio = 1.30, 95% confidence interval = 0.43-4.00; P = .64) or Cycle 2 (incident rate ratio = 0.72, 95% confidence interval = 0.30-1.75; P = .47). In Cycle 2, 1 serious, 3 moderate (single-episode group), and 24 mild (single-episode group n = 10; 2 episode group n = 14) AEs were probably/definitely related to BoNT-A.

CONCLUSIONS

Children receiving BoNT-A were at no greater risk of moderate/serious AEs compared with a sham control procedure. There was no increased risk of moderate/serious AEs between one and two episodes of BoNT-A.

Focal treatment of spasticity using botulinum toxin A in cerebral palsy cases of GMFCS level V: evaluation of adverse effects

OBJECTIVE

To report on the experience of injections of botulinum toxin A (BTA) in a series of patients with cerebral palsy of Gross Motor Function Classification System (GMFCS) level V.

METHODS

This was a retrospective case series study on 33 patients with cerebral palsy of GMFCS level V who received 89 sessions of BTA application (of which 84 were Botox(®) and five were other presentations), in which the basic aim was to look for adverse effects.

RESULTS

The mean number of application sessions per patient was three, and the mean age at the time of each injection was 4 + 6 years (range: 1.6-13 years). The muscles that most frequently received injections were the gastrocnemius, hamstrings, hip adductors, biceps brachii and finger flexors. The mean total dose was 193 U and the mean dose per weight was 12.5 U/kg. Only one patient received anesthesia for the injections and no sedation was used in any case. No local or systemic adverse effects were observed within the minimum follow-up of one month.

CONCLUSION

The absence of adverse effects in our series was probably related to the use of low doses and absence of sedation or anesthesia. According to our data, BTA can be safely used for patients with cerebral palsy of GMFCS level V, using low doses and preferably without sedation or anesthesia.

Rationale for using botulinum toxin A as an adjunct to upper limb rehabilitation in children with cerebral palsy

Cerebral palsy describes a group of disorders of movement and posture that result from disturbances in the developing brain. Although the brain lesion is nonprogressive, the secondary physical symptoms change with time and growth. If left untreated, symptoms may result in the development of physical impairment and impede independent performance of daily tasks. Intramuscular injection of botulinum neurotoxin A is a relatively safe and effective adjunct to upper limb therapy. Botulinum neurotoxin A primarily aims to reduce muscle overactivity, thereby reducing the development of increased muscle stiffness that can lead to permanent changes. With a specific focus on the physiological action of botulinum neurotoxin A, this article describes the secondary symptoms of cerebral palsy and their different contributions. To highlight research directions and future implications for clinical practice, this article also documents the recent scientific evidence for upper limb botulinum neurotoxin A and proposes a preventive clinical model that aims to mitigate the effects of increasing upper limb impairment.

Botulinum toxin type A in children and adolescents with severe cerebral palsy: a retrospective chart review

This retrospective cohort study reviewed set goals and their outcomes of children and adolescents with severe cerebral palsy who received botulinum toxin A in 2008 and 2009. Sixty children (36 male, mean age 9 years) were included. They received on average 4 (range 1-7) treatments, with the dosage varying between 20 and 400 units per treatment (3-21 U/kg/body weight). Mild transient side effects were reported in 12 of 242 treatments with botulinum toxin A. Treatment goals were related to lower limb function (82%), range of motion (68%), positioning (33%), upper limb function (33%), and facilitating ease of care in dressing (30%), toileting, and diapering (22%). The treatment goals were reached in 60% to 85% by report of the parent and child dyad. Our findings suggest that botulinum toxin A should be considered as a treatment option in patients with cerebral palsy within Gross Motor Function Classification System levels IV and V.

Use of rimabotulinum toxin for focal hypertonicity management in children with cerebral palsy with nonresponse to onabotulinum toxin

OBJECTIVE

The aim of this study was to review the effect of rimabotulinum toxin (BoNT-B) for focal hypertonicity management in children with cerebral palsy and secondary nonresponse to onabotulinum toxin treated at the authors' tertiary care academic medical center.

DESIGN

A retrospective review of the medical treatment of children was conducted at the authors' institution (March 16, 2001, to August 2, 2002) using the key words botulinum toxin B and Myobloc (Solstice Neurosciences Inc, South San Francisco, CA). Demographic information was analyzed using descriptive statistics (number [percentage] and mean [range]). The Pearson χ test was used to evaluate differences in incidence of adverse events.

RESULTS

Eighty-two children had BoNT-B injections (116 treatments). Overall, 26.8% (19/71) of the children or their parents/guardians reported no or minimal response to the injections, with 89.5% (17/19) of these children having secondary nonresponse to onabotulinum toxin. Adverse events were frequent but did not require hospitalization of any patient. No significant differences were found in incidence of adverse events related to BoNT-B dosing, medical fragility, or Gross Motor Function Classification System level.

CONCLUSIONS

More than one-fourth of the children receiving BoNT-B injections had nonresponse, with most having previous nonresponse to onabotulinum toxin. Adverse events related to BoNT-B injections were frequent and unpredictable but not severe.

Use of botulinum toxin in individuals with neurogenic detrusor overactivity: state of the art review

BACKGROUND

Botulinum neurotoxin (BoNT) injection into the bladder wall has been shown to be an effective alternative to anticholinergic (antimuscarinic) medications and more invasive surgery in those with multiple sclerosis and spinal cord injury with neurogenic detrusor overactivity (NDO) and urinary incontinence who are not tolerating anticholinergic medications. In August 2011, Botox(®) (onabotulinumtoxinA) received Food and Drug Administration (FDA) approval for this use. Clinically, intradetrusor injection of BoNT has been found to decrease urinary incontinence and improve quality of life. Its impact on urodynamic parameters is an increase in the maximum cystometric (bladder) capacity and decrease in the maximum detrusor pressures. The most common side effects are urinary tract infections and urinary retention. There have been rare reports and a black box warning of distant spread of BoNT. BoNT has gained popularity because of its effectiveness and long duration of action, relative ease of administration, easy learning curve, reproducibility of results on repeated administration, and low incidence of complications.

OBJECTIVE

To discuss the structure and function, mechanisms of action, clinical and urodynamic studies, injection technique, potential beneficial and adverse effects, and potential areas of research of BoNT.

METHODS

Literature search focused on botulinum toxin in MEDLINE/PubMed. Search terms included botulinum toxin, neurogenic bladder, NDO, botox bladder, botox spinal cord injury, botox, FDA, botox side effects. All papers identified were English language, full-text papers. In addition, English abstracts of non-English papers were noted. The reference list of identified articles was also searched for further papers.

CONCLUSION

Botulinum toxin is an alternative treatment for individuals with NDO who fail to tolerate anticholinergic medications. Its popularity has increased because of the literature, which has supported its effectiveness, safety, easy use and learning curve, reproducibility of results on repeated use, and recent FDA approval of Botox(®) (onabotulinumtoxinA).

Muscle volume alterations in spastic muscles immediately following botulinum toxin type-A treatment in children with cerebral palsy

AIM

With evidence for an atrophic effect of botulinum toxin type A (BoNT-A) documented in typically developing muscles, this study investigated the immediate morphological alterations of muscles in children with cerebral palsy (CP) after BoNT-A treatment.

METHOD

Fifteen children (10 males, five females; age range 5-11y, mean age 8y 5mo, SD 1y 10mo) with spastic diplegic CP [Gross Motor Function Classification System Levels I (n=9) and II (n=6)] receiving BoNT-A injections for spasticity management were included. None of the children was a first-time receiver of BoNT-A. Magnetic resonance imaging and Mimics software assessed muscle volume, timed 2 weeks before and 5 weeks after injection. All participants received BoNT-A bilaterally to the gastrocnemius muscle, and five participants also received BoNT-A bilaterally to the medial hamstring muscles. Functional assessment measures used were the 6-Minute Walk Test (6-MWT), the Timed Up and Go (TUG) test, and hand-held dynamometry.

RESULTS

Whilst total muscle group volume of the injected muscle group remained unchanged, a 4.47% decrease in the injected gastrocnemius muscle volume (p=0.01) and a 3.96% increase in soleus muscle volume (p=0.02) was evident following BoNT-A. There were no statistically significant changes in function after BoNT-A as assessed by the TUG. There was also no statistically significant change in distance covered in the 6-MWT. Muscle strength, as assessed using hand-held dynamometry was also not statistically different after BoNT-A treatment.

INTERPRETATION

Muscle volume decreases were observed in the injected muscle (gastrocnemius), with synergistic muscle hypertrophy that appeared to compensate for this decrement. The 4% to 5% decrease in the volume of BoNT-A injected muscles are not dramatic in comparison to reports in recent animal studies, and are a positive indication for BoNT-A, particularly as it also did not negatively alter function.

Safety of botulinum toxin A in children and adolescents with cerebral palsy in a pragmatic setting

This retrospective study aimed to examine the safety of botulinum toxin A (BoNT-A) treatment in a paediatric multidisciplinary cerebral palsy clinic. In a sample of 454 patients who had 1515 BoNT-A sessions, data on adverse events were available in 356 patients and 1382 sessions; 51 non-fatal adverse events were reported (3.3% of the total injections number, 8.7% of the patients). On five occasions, the adverse reactions observed in GMFCS V children were attributed to the sedation used (rectal midazolam plus pethidine; buccal midazolam) and resulted in prolongation of hospitalization. Of the reactions attributed to the toxin, 23 involved an excessive reduction of the muscle tone either of the injected limb(s) or generalized; others included local pain, restlessness, lethargy with pallor, disturbance in swallowing and speech production, seizures, strabismus, excessive sweating, constipation, vomiting, a flu-like syndrome and emerging hypertonus in adjacent muscles. Their incidence was associated with GMFCS level and with the presence of epilepsy (Odds ratio (OR) = 2.74 - p = 0.016 and OR = 2.35 - p = 0.046, respectively) but not with BoNT-A dose (either total or per kilogram). In conclusion, treatment with BoNT-A was safe; adverse reactions were mostly mild even for severely affected patients. Their appearance did not necessitate major changes in our practice.

Botulinum toxin-A use in paediatric hypertonia: Canadian practice patterns

BACKGROUND

This study aims to assess current practices of Canadian physicians providing botulinum toxin-A (BoNT-A) treatments for children with hypertonia and to contrast these with international "best practice" recommendations, in order to identify practice variability and opportunities for knowledge translation.

METHODS

Thirteen Canadian physicians assembled to develop and analyze results of a cross-sectional electronic survey, sent to 50 physicians across Canada.

RESULTS

Seventy-eight percent (39/50) of physicians completed the survey. The most frequently identified assessment tools were Gross Motor Function Classification System, Modified Tardieu Scale and neurological examination. Goal-setting tools were infrequently utilized. Common indications for BoNT-A injections and the muscles injected were identified. Significant variability was identified in using BoNT-A for hip displacement associated with hypertonia. The most frequent adverse event reported was localized weakness; 54% reporting this "occasionally" and 15% "frequently". Generalized weakness, fatigue, ptosis, diplopia, dysphagia, aspiration, respiratory distress, dysphonia and urinary incontinence were reported rarely or never. For dosage, 52% identified 16 Units/kg body weight of Botox® as maximum. A majority (64%) reported a maximum 400 Units for injection at one time. For localization, electrical stimulation and ultrasound were used infrequently (38% and 19% respectively). Distraction was the most frequently used pain-management technique (64%).

CONCLUSIONS

Canadian physicians generally adhere to international best practices when using BoNT-A to treat paediatric hypertonia. Two knowledge-translation opportunities were identified: use of individualized goal setting prior to BoNT-A and enhancing localization techniques. Physicians reported a good safety profile of BoNT-A in children.

Evaluation of the effects of botulinum toxin A injections when used to improve ease of care and comfort in children with cerebral palsy whom are non-ambulant: a double blind randomized controlled trial

Background

Children with cerebral palsy (CP) whom are non-ambulant are at risk of reduced quality of life and poor health status. Severe spasticity leads to discomfort and pain. Carer burden for families is significant. This study aims to determine whether intramuscular injections of botulinum toxin A (BoNT-A) combined with a regime of standard therapy has a positive effect on care and comfort for children with CP whom are non-ambulant (GMFCS IV/V), compared with standard therapy alone (cycle I), and whether repeated injections with the same regime of adjunctive therapy results in greater benefits compared with a single injecting episode (cycle II). The regime of therapy will include serial casting, splinting and/or provision of orthoses, as indicated, combined with four sessions of goal directed occupational therapy or physiotherapy.

Method/design

This study is a double blind randomized controlled trial. Forty participants will be recruited. In cycle I, participants will be randomized to either a treatment group who will receive BoNT-A injections into selected upper and/or lower limb muscles, or a control group who will undergo sham injections. Both groups will receive occupational therapy and /or physiotherapy following injections. Groups will be assessed at baseline then compared at 4 and 16 weeks following injections or sham control. Parents, treating clinicians and assessors will be masked to group allocation. In cycle II, all participants will undergo intramuscular BoNT-A injections to selected upper and/or lower limb muscles, followed by therapy.

The primary outcome measure will be change in parent ratings in identified areas of concern for their child’s care and comfort, using the Canadian Occupational Performance Measure (COPM). Secondary measures will include the Care and Comfort Hypertonicity Scale (ease of care), the Cerebral Palsy Quality of Life Questionnaire (CP QoL–Child) (quality of life), the Caregiver Priorities and Child Health Index of Life with Disabilities Questionnaire (CPCHILD©) (health status) and the Paediatric Pain Profile (PPP) (pain). Adverse events will be carefully monitored by a clinician masked to group allocation.

Discussion

This paper outlines the theoretical basis, study hypotheses and outcome measures for a trial of BoNT-A injections and therapy for children with non-ambulant CP.

Trial registration

Australia New Zealand Clinical Trials Registry:N12609000360213

Effectiveness and safety of botulinum toxin type a in children with musculoskeletal conditions: what is the current state of evidence?

Children with musculoskeletal conditions experience muscle weakness, difficulty walking and limitations in physical activities. Standard treatment includes physiotherapy, casting, and surgery. The use of botulinum toxins appears as a promising treatment on its own, but usually as an adjunct to other treatment modalities and as an alternative to surgery. The objectives were to establish the evidence on the effectiveness, safety and functional outcome of BTX-A in children with musculoskeletal conditions. A literature search using five electronic databases identified 24 studies that met our inclusion criteria. Two randomized clinical trials were included; most studies were case studies with small sample sizes and no control group. Improvements in gait pattern, function, range of motion, reduction of co-contractions, and avoidance of surgical procedures were found following BTX-A injections. Adverse events were not reported in 10 studies, minor adverse events were reported in 13 children and there were no severe adverse events. Additional doses appear safe. BTX-A is a promising treatment adjunct in improving functional outcomes in children with musculoskeletal conditions. Future studies including larger samples, longer follow-up periods and a comparison group are required to provide evidence on the effectiveness and safety of this drug in children with musculoskeletal conditions.

Use of botulinum toxin A in management of children with cerebral palsy

QUESTION

What is the role of intramuscular botulinum toxin injections in the management of spasticity and related morbidity in children with cerebral palsy?

ANSWER

When botulinum toxin A is injected into the limbs of children with spastic paresis, it induces temporary reduction in muscle tone. It also promotes better motor function when used in combination with conservative treatments such as physiotherapy. Although there is a growing body of evidence for its effective and safe treatment, there is still a lack of consensus on dose, treatment regimens, and the best integration with other clinical modalities.