Botulinum toxin treatment of children with cerebral palsy - a short review of different injection techniques

Methods of muscle spasticity assessment in children with cerebral palsy: a scoping review

BACKGROUND

Evaluating muscle spasticity in children with cerebral palsy (CP) is essential for determining the most effective treatment strategies. This scoping review assesses the current methods used to evaluate muscle spasticity, highlighting both traditional and innovative technologies, and their respective advantages and limitations.

METHODS

A search (to April 2024) used keywords such as muscle spasticity, cerebral palsy, and assessment methods. Selection criteria included articles involving CP children, assessing spasticity objectively/subjectively, comparing methods, or evaluating method effectiveness.

RESULTS

From an initial pool of 1971 articles, 30 met our inclusion criteria. These studies collectively appraised a variety of techniques ranging from well-established clinical scales like the modified Ashworth Scale and Tardieu Scale, to cutting-edge technologies such as real-time sonoelastography and inertial sensors. Notably, innovative methods such as the dynamic evaluation of range of motion scale and the stiffness tool were highlighted for their potential to provide more nuanced and precise assessments of spasticity. The review unveiled a critical insight: while traditional methods are convenient and widely used, they often fall short in reliability and objectivity.

CONCLUSION

The review discussed the strengths and limitations of each method and concluded that more reliable methods are needed to measure the level of muscle spasticity more accurately.

Ultrasound-Guided Injections for Treatment of Facial Paralysis Sequelae: A Randomized Study on Body Donors

BACKGROUND

Botulinum toxin injection is the accepted standard treatment for synkinesis and gustatory hyperlacrimation in patients with facial paralysis. However, poor injection accuracy can result in inconsistent treatment outcomes, variable treatment durations, and complications. Ultrasound guidance should increase injection accuracy in the facial region; however, this has not been proven.

METHODS

Twenty-six hemifaces of nonembalmed cadavers were studied in a randomized split-face manner. Ink was injected with ultrasound or landmark guidance into the lacrimal gland and three common synkinetic muscles: the orbicularis oculi, depressor anguli oris, and mentalis. Injection accuracy was evaluated using several measures.

RESULTS

Using ultrasound guidance, most ink (>50%) was found inside the correct target in 88% of cases, compared with 50% using landmark guidance ( P < 0.001). This was most pronounced in the lacrimal gland (62% versus 8%), depressor anguli oris (100% versus 46%), and mentalis (100% versus 54%) ( P < 0.05). All ink was found inside the correct target (no ink outside) in 65% using ultrasound guidance versus 29% without ( P < 0.001). Injection accuracy (any ink in target) was 100% when using ultrasound guidance versus 83% without ( P < 0.01). Twenty-three percent of the landmark-guided depressor anguli oris injections stained the facial artery ( P = 0.22).

CONCLUSIONS

Ultrasound guidance significantly increased injection accuracy and reduced the amount of ink lost in the surrounding tissue compared with landmark guidance. Clinical trials are needed to explore the effects of ultrasound guidance on treatment outcome, duration, and complications in patients with facial paralysis.

The effectiveness of ultrasound-guided injection of BTX-A in the management of sialorrhea in neurogenic dysphagia patients

Objective

To evaluate the effectiveness of ultrasound-guided injection of botulinum toxin type A (BTX-A) in treating sialorrhea.

Methods

We recruited 32 sialorrhea subjects and they received an ultrasound-guided injection of BTX-A. The extent of salivation was evaluated according to the Visual Analog Scale (VAS), Drooling Severity and Frequency Scale (DSFS), and Saliva Flow Rate (SFR). Laryngeal secretions were evaluated based on Fiberoptic Endoscopic Evaluation of Swallowing (FEES) rated according to the Murray Secretion Scale (MSS). We assessed the extent of salivation and laryngeal secretions before injection and at 1, 2, and 4 weeks after injection.

Results

The scores for the VAS, DSFS-S, DSFS-F, and DSFS-T decreased significantly at 1, 2, and 4 weeks after injection compared with before injection (p < .05). Based on VAS, the efficacy was substantially higher at 2 and 4 weeks after injection than at 1 week after injection (p < .05). According to DSFS-S and DSFS-T, the efficacy was significantly higher at 4 weeks than at 1 week after injection (p < .05). The SFR and MSS scores at 1 and 2 weeks after injection were superior to those before injection (p < .05). Meanwhile, the SFR score 2 weeks after injection was superior to that 1 week after injection (p < .05).

Conclusion

The ultrasound-guided injection of BTX-A can effectively reduce saliva secretion in patients with neurogenic dysphagia. Furthermore, it has the advantages of early onset time and lasting curative effects, which indicates that clinical promotion and application of this technique are justified.

Level of Evidence

Level 3.

IncobotulinumtoxinA Efficacy/Safety in Upper-Limb Spasticity in Pediatric Cerebral Palsy: Randomized Controlled Trial

BACKGROUND

This randomized phase 3 study with double-blind main period (MP) and open-label extension (OLEX; NCT02002884) assessed incobotulinumtoxinA safety and efficacy for pediatric upper-limb spasticity treatment in ambulant/nonambulant (Gross Motor Function Classification System [GMFCS] I-V) patients, with the option of combined upper- and lower-limb treatment.

METHODS

Patients were aged two to 17 years with unilateral or bilateral spastic cerebral palsy (CP) and Ashworth Scale (AS) score ≥2 in treatment-selected clinical patterns. In the MP, patients were randomized (2:1:1) to incobotulinumtoxinA 8, 6, or 2 U/kg body weight (maximum 200, 150, 50 U/upper limb), with optional lower-limb injections in one of five topographical distributions (total body dose ≤16 to 20 U/kg, maximum 400 to 500 U, depending on body weight and GMFCS level). In the OLEX, patients received three further treatment cycles, at the highest MP doses (8 U/kg/upper limb group). Outcomes included AS, Global Impression of Change Scale (GICS), and adverse events (AEs).

RESULTS

AS scores improved from baseline to week 4 in all MP dose groups (n = 350); patients in the incobotulinumtoxinA 8 U/kg group had significantly greater spasticity improvements versus the 2 U/kg group (least-squares mean [standard error] for upper-limb main clinical target pattern -1.15 [0.06] versus -0.93 [0.08]; P = 0.017). Investigator's, child/adolescent's, and parent/caregiver's GICS scores showed improvements in all groups. Treatment benefits were sustained over further treatment cycles. AE incidence did not increase with dose or repeated treatment across GMFCS levels.

CONCLUSIONS

Data provide evidence for sustained efficacy and safety of multipattern incobotulinumtoxinA treatment in children and adolescents with upper-limb spasticity.

Over 25 Years of Pediatric Botulinum Toxin Treatments: What Have We Learned from Injection Techniques, Doses, Dilutions, and Recovery of Repeated Injections?

Botulinum toxin type A (BTXA) has been used for over 25 years in the management of pediatric lower and upper limb hypertonia, with the first reports in 1993. The most common indication is the injection of the triceps surae muscle for the correction of spastic equinus gait in children with cerebral palsy. The upper limb injection goals include improvements in function, better positioning of the arm, and facilitating the ease of care. Neurotoxin type A is the most widely used serotype in the pediatric population. After being injected into muscle, the release of acetylcholine at cholinergic nerve endings is blocked, and a temporary denervation and atrophy ensues. Targeting the correct muscle close to the neuromuscular junctions is considered essential and localization techniques have developed over time. However, each technique has its own limitations. The role of BTXA is flexible, but limited by the temporary mode of action as a focal spasticity treatment and the restrictions on the total dose deliverable per visit. As a mode of treatment, repeated BTXA injections are needed. This literature reviewed BTXA injection techniques, doses and dilutions, the recovery of muscles and the impact of repeated injections, with a focus on the pediatric population. Suggestions for future studies are also discussed.

A Randomized Control Trial of Botulinum Toxin A Administration under Ultrasound Guidance against Manual Palpation in Spastic Cerebral Palsy

Background:

Botulinum toxin A is established as an effective treatment to reduce spasticity in cerebral palsy (CP). But very little data are available regarding the techniques of administration. Hence, this study was conducted to compare administration of botulinum toxin with and without ultrasound.

Materials and Methods:

This is a randomized trial conducted for 2 years at a tertiary care hospital in children aged up to 6 years with CP. Children were assessed with range of ankle dorsiflexion, Modified Ashworth Scale (MAS), and Gross Motor Function Measure 66(GMFM 66) before and after administration. They were followed up for 6 months.

Results:

Of the 180 children screened, 30 who met the criteria were included. Those enrolled in the study were categorized into group I and group II, children who were given botulinum toxin with ultrasound (n = 14) and without ultrasound (n = 16), respectively. Results showed a significant increase in ankle dorsiflexion in both groups (P ≤ 0.005) but no significant difference was reported between the groups (P = 0.4). A statistically significant increase in GMFM scores (P ≤ 0.005) during sequential assessment was observed in both groups, but no significant difference was observed in the GMFM scores between the groups (P = 0.45). Majority of children improved by a scale of 2 (MAS) from baseline in groups after 12 weeks, 50% in group I and 57.9% in group II.

Conclusion:

No significant difference was observed in the outcome with regard to technique of administration of botulinum toxin with ultrasound and without ultrasound into gastrocnemius muscle.

Ultrasound Guidance for Botulinum Neurotoxin Chemodenervation Procedures

Injections of botulinum neurotoxins (BoNTs) are prescribed by clinicians for a variety of disorders that cause over-activity of muscles; glands; pain and other structures. Accurately targeting the structure for injection is one of the principle goals when performing BoNTs procedures. Traditionally; injections have been guided by anatomic landmarks; palpation; range of motion; electromyography or electrical stimulation. Ultrasound (US) based imaging based guidance overcomes some of the limitations of traditional techniques. US and/or US combined with traditional guidance techniques is utilized and or recommended by many expert clinicians; authors and in practice guidelines by professional academies. This article reviews the advantages and disadvantages of available guidance techniques including US as well as technical aspects of US guidance and a focused literature review related to US guidance for chemodenervation procedures including BoNTs injection.

The role of the paravertebral muscles in adolescent idiopathic scoliosis evaluated by temporary paralysis

Background

Muscle imbalance has been suggested as implicated in the pathology of adolescent idiopathic scoliosis (AIS). The specific “pathomechanic” role of the paravertebral muscles as being scoliogenic (inducing scoliosis) or counteracting scoliosis in the initial development and maintenance of this spinal deformity has yet to be clarified in humans. In the present study, we investigated the radiographic changes of temporal paralysis using botulinum toxin A as localized injection therapy (ITB) in the psoas major muscle in AIS patients.

Methods

Nine patients with AIS were injected one time with ITB using ultrasonic and EMG guidance in the selected spine muscles. Radiographic and clinical examinations were performed before and 6 weeks after the injection. Primary outcome parameters of radiological changes were analyzed using Wilcoxon signed-rank test and binomial test, and secondary outcome parameters of short- and long-term clinical effects were obtained.

Results

Significant radiological corrective changes were seen in the frontal plane in the thoracic and lumbar spine as well as significant derotational corrective change in the lumbar spine according to Cobb’s angle measurements and to Nash and Moe’s classification, respectively. No serious adverse events were detected at follow-up.

Conclusions

In conclusion, this study demonstrated that the psoas major muscle do play a role into the pathology in adolescent idiopathic scoliosis by maintaining the curvature of the lumbar spine and thoracic spine.

Trial registration

EudraCT number 2008-004584-19

Clinical study of botulinum toxin A injection combined with spasmodic muscle therapeutic instrument on lower limb spasticity in patients with stroke

The clinical effect of botulinum toxin A (BTX-A) injection combined with spasmodic muscle therapeutic instrument with simple BTX-A injection was compared. Eighty patients with stroke were randomly divided into the treatment and control groups of 41 and 39 cases, respectively. The two groups of patients were given routine rehabilitation therapy. Ultrasound-guide positioning technology was used; treatment group was administered BTX-A injection combined spasmodic muscle therapeutic instrument while the control group received only BTX-A injection. Muscle tension and motor function were evaluated at 1, 4, 8 and 12 weeks after treatments by rehabilitation physician who was not aware of the grouping of the patients. Muscle tension was significantly reduced after BTX-A injection in the treatment and control groups. Modified Ashworth scale scores of the treatment and control groups 1 and 4 weeks after treatment were significantly lower than those before treatment. Motor function of lower limbs of patients, 1 and 4 weeks after treatment improved significantly. The comparison of step size and walking speed of the groups showed obvious differences with statistical significance (P<0.01). In conclusion, ultrasonic guidance BTX-A injection is easy to operate with good safety. It can effectively improve extensor myospasm of lower limb of patients with rapid onset and the spasm relief can last for three months. Spasmodic muscle therapeutic instrument can improve the spasm condition of lower limb muscle after stroke as well as motor function of lower limbs and activity of daily living, which can make spasmolysis of BTX-A last for a longer period of time.

Botulinum neurotoxin treatment in children with cerebral palsy: validation of a needle placement protocol using passive muscle stretching and relaxing

AIM

To validate a detailed intramuscular needle placement protocol using passive muscle stretching and relaxing for botulinum neurotoxin type A (BoNT-A) treatment in the lower extremity of children with spastic cerebral palsy (CP), with verification by electrical stimulation.

METHOD

A prospective observational study was performed in 75 children with spastic CP who received regular BoNT-A treatment under general anaesthesia (52 males, 23 females; mean age 8y 9mo, SD 3y 7mo, range 4-18y; mean body mass index 16.2, SD 3.7, range 7.7-26.7). A total of 1084 intramuscular needle placements using passive muscle stretching and relaxing were verified by electrical stimulation. Primary outcome was the positive predictive value.

RESULTS

Intramuscular needle placement in the muscles adductor brevis, adductor longus, gracilis, semimembranosus, semitendinosus, biceps femoris, rectus femoris, and lateral and medial heads of the gastrocnemius and soleus had a positive predictive value ranging from 85.7% to 100% (95% confidence interval ranging from 71.5-89.9% to 91.4-100%).

INTERPRETATION

This validated detailed protocol for intramuscular needle placement using passive muscle stretching and relaxing for BoNT-A treatment in the lower extremity of children with spastic CP is reliable and has a high positive predictive value.

Efficacy of two injection-site localisation techniques for botulinum toxin injections: a single-blind, crossover, randomised trial protocol among adults with hemiplegia due to stroke

INTRODUCTION

Botulinum toxin injections are an effective treatment for limb spasticity following stroke. Different tracking techniques are used for this purpose: palpation, electrostimulation, electromyography and ultrasound. Yet very few studies have compared these different techniques, and none has successfully proved the superior efficacy of ultrasound-guided injections compared to another tracking method. The primary objective of our study was therefore to compare the efficacy of botulinum toxin injections depending on the tracking technique used: ultrasound versus electrostimulation.

METHODS AND ANALYSIS

This is a clinical, single-centre, prospective, interventional, single-blind, crossover, randomised trial. In total, 30 patients aged between 18 and 80 years presenting with triceps surae spasticity (evaluated >1 on the modified Ashworth scale) associated with hemiplegia sequelae due to stroke will be included. The patients will be selected among those who attend for consultation the Physical Medicine and Rehabilitation Department of the Clermont-Ferrand University Hospital. One group will receive the abobotulinumtoxinA (BoNT-A) injection guided by electrostimulation then ultrasound, and the second group's botulinum toxin injections will be guided by ultrasound then electrostimulation. For each patient, the duration of study participation is 5 months. The primary end point is variation in passive ankle dorsiflexion range of motion at slow and high speeds (Tardieu scale) with the knee straight.

ETHICS AND DISSEMINATION

This study received ethics approval form the CPP of Rhônes-Alpes region. Results will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT01935544; pre-results.

Evaluation of clinical outcomes of patients with post-stroke wrist and finger spasticity after ultrasonography-guided BTX-A injection and rehabilitation training

Objective: Using ultrasonography (US) to guide botulinum toxin type A (BTX-A) injection in patients with post-stroke wrist and finger flexor muscle spasticity and assessing clinical outcomes after the injection and rehabilitation intervention.

Methods: Twenty-three patients with wrist and finger spasticity after stroke were recruited in this study from May 2012 to May 2013. Under US guidance, the proper dose (250 U) of BTX-A was injected into each spastic muscle at two injection sites. Then, conventional rehabilitation training started next day after BTX-A injection. The degree of spasticity was assessed by modified Ashworth scale (MAS) and wrist and finger motor function by active rang of movement (AROM), and Fugl-Meyer assessment (FMA) at the baseline, 1, 2, 4 and 12 weeks after BTX-A injection.

Results: Significant decreases (p < 0.02) in the MAS scores of both the finger flexor muscle tone and wrist flexor muscle tone measured at 1, 2, 4, and 12 weeks after the BTX-A injection were found in comparison with the baseline scores. Compared with the baseline, the AROM values of the wrist and finger extensions and the FMA scores of the wrist and hand significantly increased (p < 0.02) at 2, 4 and 12 weeks after the BTX-A injection.

Conclusions: US-guided BTX-A injection combined with rehabilitation exercise decrease spasticity of the wrist and finger flexor muscles and improve their motor function in stroke patients up to 12 weeks following BTX-A injection.

Impact of Injection-Guiding Techniques on the Effectiveness of Botulinum Toxin for the Treatment of Focal Spasticity and Dystonia: A Systematic Review

OBJECTIVE

To conduct a systematic review of the impact of different injection-guiding techniques on the effectiveness of botulinum toxin type A (BoNT-A) for the treatment of focal spasticity and dystonia.

DATA SOURCES

MEDLINE via PubMed, Academic Search Premier, PASCAL, The Cochrane Library, Scopus, SpringerLink, Web of Science, EM Premium, and PsycINFO.

STUDY SELECTION

Two reviewers independently selected studies based on predetermined inclusion criteria.

DATA EXTRACTION

Data relating to the aim were extracted. Methodological quality was graded independently by 2 reviewers using the Physiotherapy Evidence Database assessment scale for randomized controlled trials (RCTs) and the Downs and Black evaluation tool for non-RCTs. Level of evidence was determined using the modified Sackett scale.

DATA SYNTHESIS

Ten studies were included. Seven were randomized. There was strong evidence (level 1) that instrumented guiding (ultrasonography [US], electrical stimulation [ES], electromyogram [EMG]) was more effective than manual needle placement for the treatment of spasmodic torticollis, upper limb spasticity, and spastic equinus in patients with stroke, and spastic equinus in children with cerebral palsy. Three studies provided strong evidence (level 1) of similar effectiveness of US and ES for upper and lower limb spasticity in patients with stroke, and spastic equinus in children with cerebral palsy, but there was poor evidence or no available evidence for EMG or other instrumented techniques.

CONCLUSIONS

These results strongly recommend instrumented guidance of BoNT-A injection for the treatment of spasticity in adults and children (ES or US), and of focal dystonia such as spasmodic torticollis (EMG). No specific recommendations can be made regarding the choice of instrumented guiding technique, except that US appears to be more effective than ES for spastic equinus in adults with stroke.

Electromyographic control of botulinum toxin a injections in the upper extremities in patients with spasticity of various etiology

AIM

The study was aimed at studying the efficacy of botulinum toxin A injections combined with EMG-control of the injections in patients with upper limb spasticity of various etiology for decreasing muscle tone and improving the passive limb function as well as at assessing the possibility of a botulinum toxin dose reduction under combination of these methods.

MATERIAL AND METHODS

61 patients with upper limb spasticity of different etiology were evaluated. The main group consisted of 29 patients who were injected with abobotulinum, the botulinum toxin A (500 U per vial), under EMG-control. The control group consisted of 32 patients who received BTA injections without EMG-control. A repeated BTA injection was performed on the 4th month of the study. Patients in both groups received standard rehabilitation therapy. The spasticity pattern was determined using the Arm Spasticity Pattern (ASP) scale. Evaluation of the treatment efficacy was performed using the modified Ashworth scale to determine upper limb spasticity and the modified Barthel Index scale to assess the quality of life as well as the Disability Assessment Scale (DAS) and Clinical Global Impression (CGI) scale.

RESULTS

The main spasticity patterns were as follows: the type III was in 13 (44.8%) and 17 (53.1%) patients, the type I was in 9 (31.0%) and 9 (28.1%) patients, and the type VI was in 7 (24.2%) and 6 (18.8%) patients of the main and control groups, respectively. One month after BTA treatment, a significant improvement was observed in both groups, but the improvement in the main group was more pronounced compared to that in the control group (р<0.05). This difference persisted for the whole treatment period (р<0.05). The DAS score demonstrated improvement in both groups, but only patients of the main group had a statistically significant improvement in putting the arm through a sleeve (р<0.05). EMG-control enabled a reduction in the BTA dose by 50-300 U.

CONCLUSION

BTA injections under EMG-control in upper limb spasticity patients may improve the treatment efficacy.

Applications of musculoskeletal ultrasonography in pediatric patients

Ultrasonography is an excellent adjunct to other musculoskeletal imaging tools utilized in the pediatric population and in some instances offers advantages over CT and MRI. It permits dynamic examination of anatomic structures and assists in guiding minimally invasive procedures. In the lower extremity, ultrasonography assists in screening for such disorders as developmental dysplasia of the hip and in detecting slipped capital femoral epiphysis and femoral acetabular impingement. In the neonatal spine, ultrasonography can identify unossified vertebral arches. Among other applications in the upper extremity, ultrasonography may be used in the evaluation and examination of peripheral nerve injuries and is a preferred modality for imaging the shoulder in infants with neonatal brachial plexus palsy. It is also considered an optimal adjunct for administration of botulinum toxin-A in children with cerebral palsy. The portability, relative low cost, lack of radiation, and absence of known contraindications enhances the utility of ultrasonography in pediatric orthopaedics.

Pain during injections of botulinum toxin in children: Influence of the localization technique

OBJECTIVE

In this study, we consider two localization techniques used in injections of botulinium toxin in children: electrical stimulation and ultrasound. The hypothesis of this work was that injections performed without stimulation would be less painful.

PATIENTS AND METHODS

Monocentric prospective study, with 107 sessions of lower limb injections. Two groups of children were compared: localization by ultrasound only (60 children), detection by stimulation only or by stimulation combined with ultrasound (47 children). Pain assessment was performed by the child or an accompanying party using the Visual Analog Scale (VAS) and by a health care team using the Face, Legs, Activity, Cry, Consolability (FLACC).

RESULTS

A significant difference between the two groups was found in both self-report and by means of the behavioral observational pain scale. Indeed, VAS average and FLACC average were significantly higher with detection by stimulation than with ultrasound alone: 4.5cm±2.54 versus 2.7cm±2.27; P<0.001 for VAS scale and 3.7±2.1 versus 2.7±2.3; P<0.05 for FLACC scale.

CONCLUSION

When compared to ultrasound detection, localization by electrostimulation appears to increase the overall pain caused during injections of botulinum toxin in children.

Study protocol: precision of a protocol for manual intramuscular needle placement checked by passive stretching and relaxing of the target muscle in the lower extremity during BTX-A treatment in children with spastic cerebral palsy, as verified by means of electrical stimulation

BACKGROUND

Intramuscular injection of botulinum toxin type-A given by manual intramuscular needle placement in the lower extremity under general anaesthesia is an established treatment and standard of care in managing spasticity in children with spastic cerebral palsy. Optimal needle placement is essential. However, reports of injection and verification techniques used in previous studies have been partly incomplete and there are methodological shortcomings. This paper describes a detailed protocol for manual intramuscular needle placement checked by passive stretching and relaxing of the target muscle for each individual muscle injection location in the lower extremity during botulinum toxin type-A treatment under general anaesthesia in children with spastic cerebral palsy. It explains the design of a study to verify this protocol, which consists of an injection technique combined with a needle localizing technique, as by means of electrical stimulation to determine its precision.

METHODS

SETTING

University Medical Centre, Department of Paediatric Rehabilitation Medicine, the Netherlands.

DESIGN

prospective observational study.

PARTICIPANTS

children with spastic cerebral palsy, aged 4 to 18 years, receiving regular botulinum toxin type-A treatment under general anaesthesia to improve their mobility, are recruited from the Department of Paediatric Rehabilitation Medicine at VU University Medical Centre, Amsterdam, the Netherlands.

METHOD

a detailed protocol for manual intramuscular needle placement checked by passive stretching and relaxing of the target muscle has been developed for each individual muscle injection location of the adductor brevis muscle, adductor longus muscle, gracilis muscle, semimembranosus muscle, semitendinosus muscle, biceps femoris muscle, rectus femoris muscle, gastrocnemius lateralis muscle, gastrocnemius medialis muscle and soleus muscle. This protocol will be verified as by means of electrical stimulation.Technical details: 25 mm or 50 mm Stimuplex-needle and a Stimuplex-HNS-12 electrical stimulator will be used.

DISCUSSION

Botulinum toxin type-A injected in the intended muscle is expected to yield the greatest effect in terms of activities. Protocols for manual intramuscular needle placement should be described in detail and verified to determine its precision. Detailed and verified protocols are essential to be able to interpret the results of botulinum toxin type-A treatment studies.

Accurate targeting of botulinum toxin injections: how to and why

Botulinum toxin (BTX), the exotoxin of the obligate anaerobe, Clostridium botulinum, is used to ameliorate pain and treat conditions associated with glandular, smooth and skeletal muscle overactivity. The benefits derived from the injection of BTX may be negated by unintended weakness of uninjected muscles. Performance of BTX injections may be facile, requiring only surface marking or clinical-localisation techniques but may be more technically demanding, necessitating the use of equipment, such as electromyography (EMG) or ultrasonography (U/S). Less often, endoscopic, fluoroscopic or computed tomographic (CT) guidance may be required. Despite evidence to support the efficacy of BTX injections in treating many conditions, there is no evidence to support the superiority of any one injection technique over needle localisation using surface anatomy. This is possibly due to the lack of well-designed controlled studies, that is, current studies are hampered by small patient numbers, lack of consistency of injection technique and the application of different rating scales. Intuitively, certain injection techniques are more suited to injection of specific muscles or conditions, for example, U/S or passive-monitoring EMG should be used to treat cervical dystonia, active-monitoring EMG applied for strabismus injections, whereas either active-monitoring EMG or endoscopy is indicated when giving BTX for spasmodic dysphonia. Finally, electrical-stimulation EMG or U/S (or a combination of both) would be most suitable when injecting the forearm muscles for spasticity or writer's cramps.

Botulinum toxin assessment, intervention and after-care for lower limb spasticity in children with cerebral palsy: international consensus statement

Botulinum neurotoxin type-A (BoNT-A) has been used in association with other interventions in the management of spasticity in children with cerebral palsy (CP) for almost two decades. This consensus statement is based on an extensive review of the literature by an invited international committee. The use of BoNT-A in the lower limbs of children with spasticity caused by CP is reported using the American Academy of Neurology Classification of Evidence for therapeutic intervention. Randomized clinical trials have been grouped into five areas of management, and the outcomes are presented as treatment recommendations. The assessment of children with CP and evaluation of outcomes following injection of BoNT-A are complex, and therefore, a range of measures and the involvement of a multidisciplinary team is recommended. The committee concludes that injection of BoNT-A in children with CP is generally safe although systemic adverse events may occur, especially in children with more physical limitations (GMFCS V). The recommended dose levels are intermediate between previous consensus statements. The committee further concludes that injection of BoNT-A is effective in the management of lower limb spasticity in children with CP, and when combined with physiotherapy and the use of orthoses, these interventions may improve gait and goal attainment.

Botulinum toxin assessment, intervention and follow-up for paediatric upper limb hypertonicity: international consensus statement

The primary objective of this paper was to evaluate the published evidence of efficacy and safety of botulinum neurotoxin (BoNT) injections in paediatric upper limb hypertonia (PULH). Secondary objectives included the provision of clinical context, based on evidence and expert opinion, in the areas of assessment, child and muscle selection, dosing, and adjunctive treatment. A multidisciplinary panel of authors systematically reviewed, abstracted, and classified relevant literature. Recommendations were based on the American Academy of Neurology (AAN) evidence classification. Following a literature search, 186 potential articles were screened for inclusion, and 15 of these met the criteria and were reviewed. Grade A evidence was found to support the use of BoNT to reach individualized therapeutic goals for PULH. There is grade B evidence (probably effective) for tone reduction following BoNT injections and grade U evidence (inconclusive) for improvement in upper limb (UL) activity and function. BoNT injections were generally found to be safe and well tolerated with the most common side effect identified as a transient decrease in grip strength.

Botulinum toxin a injection into calf muscles for treatment of spastic equinus in cerebral palsy: a controlled trial comparing sonography and electric stimulation-guided injection techniques: a preliminary report

OBJECTIVE

To compare the clinical outcomes of two different injection techniques, one guided by electric stimulation and the other by sonography, for botulinum toxin A injection into calf muscles for the treatment of spastic equinus in children with cerebral palsy.

DESIGN

Thirty-two children with cerebral palsy with spastic equinus gait were enrolled in separate categories according to their level under the Gross Motor Function Classification System and divided into two groups with alternate allocation: sonography-guided group and electric stimulation-guided group. Equal amounts of botulinum toxin A were injected into the gastrocnemius at four to six points in 30 children with cerebral palsy. The injection was guided by electric stimulation in 14 and by ultrasonography in 16 children. Modified Ashworth Scale, Modified Tardieu Scale, Selective Motor Control, and Physician's Rating Scale were measured at baseline, 1 mo, and 3 mos posttreatment.

RESULTS

Subscales of the Physician's Rating Scale (gait pattern and hindfoot position-maximum foot/floor contact during stance) significantly improved in the sonography-guided group. No statistical differences were noted in Modified Ashworth Scale, Modified Tardieu Scale, and Selective Motor Control.

CONCLUSIONS

Visual feedback by ultrasonography could improve the accuracy of selective neuromuscular blocking of the gastrocnemius.

Botulinum toxin type A for upper limb spasticity after stroke

Spasticity is involuntary overactivity of muscles that occurs following upper motor neuron damage to the brain or spinal cord. Upper limb spasticity is common after stroke and can cause deformity, pain and reduced function. Botulinum toxin type A is a neurotoxin produced by the bacterium Clostridium botulinum that blocks the release of acetylcholine from cholinergic neurons. When given by intramuscular injection it causes temporary local paresis and has become an important component of focal spasticity treatment. Randomized controlled trials have shown that botulinum toxin type A can decrease upper limb spasticity and improve the ease of performing basic upper limb functional activities, such as cleaning the hand or dressing a sleeve. This article will review the pharmacology of botulinum toxin type A and its clinical efficacy when used to treat upper limb spasticity after stroke.

The updated European Consensus 2009 on the use of Botulinum toxin for children with cerebral palsy

An interdisciplinary European group of clinical experts in the field of movement disorders and experienced Botulinum toxin users has updated the consensus for the use of Botulinum toxin in the treatment of children with cerebral palsy (CP). A problem-orientated approach was used focussing on both published and practice-based evidence. In part I of the consensus the authors have tabulated the supporting evidence to produce a concise but comprehensive information base, pooling data and experience from 36 institutions in 9 European countries which involves more than 10,000 patients and over 45,000 treatment sessions during a period of more than 280 treatment years. In part II of the consensus the Gross Motor Function Measure (GMFM) and Gross Motor Function Classification System (GMFCS) based Motor Development Curves have been expanded to provide a graphical framework on how to treat the motor disorders in children with CP. This graph is named "CP(Graph) Treatment Modalities - Gross Motor Function" and is intended to facilitate communication between parents, therapists and medical doctors concerning (1) achievable motor function, (2) realistic goal-setting and (3) treatment perspectives for children with CP. The updated European consensus 2009 summarises the current understanding regarding an integrated, multidisciplinary treatment approach using Botulinum toxin for the treatment of children with CP.

Botulinum neurotoxin: evolution from poison, to research tool--onto medicinal therapeutic and future pharmaceutical panacea

Botulinum neurotoxin (BoNT), for more than a hundred years, has been a recognized poisonous principle in spoiled food. As its chemical structure became unraveled, and as more knowledge was gained over its mechanism of toxicity, it became clear that BoNT had the potential to act therapeutically as a targeted toxin that could inactivate specific nerve populations, and thus achieve a therapeutic goal. BoNT has evolved over the past 25 years into a viable therapeutic, now being a first line treatment for dystonia, overtly altering the course of progression of this disorder. BoNT is used for hyperhidrosis and gustatory sweating syndrome, alleviation of pain, as a treatment for overactive bladder, achalasia and anal fissure; and it has gained popularity as a cosmetic aid. Many other possible uses are being explored. The greatest potential for BoNT may lie in its being a molecular Trojan Horse - able to carry a specific enzyme or specific drug to the inside of a cancer or other type of cell while bypassing other cells and thereby having little or no ill effect. BoNT's pharmaceutical potential is boundless.

Botulinum toxin: description of injection techniques and examination of controversies surrounding toxin diffusion

The benefits derived from botulinum toxin (BTX) injections may be negated by unintentional weakness of adjacent uninjected muscles. Such weakness may be the result of inaccurate targeting, or diffusion of BTX to surrounding muscles. Several techniques, using electromyographic, endoscopic or imaging guidance are purported to increase the accuracy of targeting. Diffusion of BTX is thought to be influenced by factors such as dose, concentration, injectate volume, number of injections, site and rate of injection, needle gauge, muscle size, muscular fascia, distance of needle tip from the neuromuscular junction, and protein content of the BTX formulation. This article describes techniques that aim to increase the accuracy of BTX injections and examines the controversies surrounding diffusion of BTX following injection.

European consensus table 2006 on botulinum toxin for children with cerebral palsy

An interdisciplinary group of experienced botulinum toxin users and experts in the field of movement disorders was assembled, to develop a consensus on best practice for the treatment of cerebral palsy using a problem-orientated approach to integrate theories and methods. The authors tabulated the supporting evidence to produce a condensed but comprehensive information base, pooling data and experience from nine European countries, 13 institutions and more than 5500 patients. The consensus table summarises the current understanding regarding botulinum toxin treatment options in children with CP.