Intramuscular injections of botulinum toxin for the treatment of upper back myofascial pain syndrome: A systematic review of randomized controlled trials

BACKGROUND AND OBJECTIVE

Myofascial pain syndrome (MPS) is a chronic musculoskeletal disorder characterized by the presence of trigger points. Among the treatment options, botulinum toxin injections have been investigated. The aim of this paper was to provide a synthesis of the evidence on intramuscular botulinum toxin injections for upper back MPS.

DATABASES AND DATA TREATMENT

A systematic review of the literature was performed on the PubMed, Scopus and Cochrane Library, using the following formula: ("botulinum") AND ("musculoskeletal") AND ("upper back pain") OR ("myofascial pain").

RESULTS

Ten studies involving 651 patients were included. Patients in the control groups received placebo (saline solution) injections, anaesthetic injections + dry needling or anaesthetic injections. The analysis of the trials revealed modest methodological quality: one "Good quality" study, one "Fair" and the other "Poor". No major complications or serious adverse events were reported. Results provided conflicting evidence and did not demonstrate the superiority of botulinum toxin over comparators. Most of the included trials were characterized by a small sample size, weak power analysis, different clinical scores used and non-comparable follow-up periods. Even if there is no conclusive evidence, the favourable safety profile and the positive results of some secondary endpoints suggest a potentially beneficial action in pain control and quality of life.

CONCLUSION

The currently available studies show conflicting results. Their overall low methodological quality does not allow for solid evidence of superiority over other comparison treatments. Further insights are needed to properly profile patients who could benefit more from this peculiar injective approach.

SIGNIFICANCE

The randomized controlled trials included in this review compared using botulinum toxin to treat upper back MPS with placebo or active treatments (e.g., dry needling or anaesthetics) showing mixed results overall. Despite the lack of clear evidence of superiority, our study suggests that the use of botulinum toxin should not be discouraged. Its safety profile and encouraging results in pain control, motor recovery and disability reduction make it an interesting treatment, particularly in the subset of patients with moderate to severe chronic pain and active trigger points. To support the safety and efficacy of botulinum toxin, further high-quality studies are needed.

Efficiency of botulinum toxin injection into the arm on postural balance and gait after stroke

The purpose of this study was to clarify the association between improvement of spasticity in hemiplegic patient's upper extremity with Botulinum toxin injection and improvement in postural balance and gait function. For this prospective cohort study, sixteen hemiplegic stroke patients with upper extremity spasticity were recruited. The plantar pressure with gait parameters, postural balance parameters, Modified Ashworth Scale, and Modified Tardieu Scale were evaluated before, 3 weeks and 3 months after Botulinum toxin A (BTxA) injection. Spasticity of hemiplegic upper extremity before, and after BTxA injection were significantly changed. Plantar pressure overload in affected side was reduced after BTxA injection. The mean X-speed and the horizontal distance decreased in postural balance analysis with eyes-opened test. Improvement in hemiplegic upper extremity spasticity showed positive correlation with gait parameters. In addition, improvement in hemiplegic upper extremity spasticity was positively correlated with change in balance parameters in postural balance analysis with eyes-closed and dynamic tests. This study focused on the effect of stroke patient's hemiplegic upper extremity spasticity on their gait and balance parameters and identified that the BTxA injection on hemiplegic patient's spastic upper extremity improve postural balance and gait function.

Differences in causes of stiff knee gait in knee extensor activity or ankle kinematics: A cross-sectional study

BACKGROUND

Stiff knee gait (SKG), a common occurrence after the onset of stroke, is caused by hyperactivity of the rectus femoris during the swing phase. Another cause of SKG is the weakness of push-off in hemiparetic gait. Prior research did not consider the effect of the magnitude of knee extensors in their subjects.

RESEARCH QUESTION

Does the cause of SKG differ between patients with high and low knee extensor activities during the swing phase?

METHODS

We examined 38 patients with chronic stroke hemiplegia who presented with SKG. After placing an inertia sensor and an electromyogram, patients walked 10 m at a comfortable speed. All patients were categorized per the sign of the principal component 2 (PC2) as a component with large factor loadings of knee extensors attained from the electromyographic amplitude during the early swing phase of the paretic limb. Then, the kinematic parameters of knee flexion and other gait parameters in each group were compared, and a correlation analysis was performed.

RESULTS

In the high PC2 group, the timing of peak knee flexion during the swing phase was early, and vastus lateralis activity during the preswing phase negatively correlated with the knee-flexion angle during the swing phase. In the low PC2 group, the angular velocity of ankle plantar flexion at the toe-off was slow, which positively correlated with the knee-flexion angle during the swing phase.

SIGNIFICANCE

The cause of SKG could be an inappropriate activity of the vastus lateralis rather than the rectus femoris in patients with high knee extensor activity and slow plantar-flexion velocity at toe-off in patients with low knee extensor activity. Not all causes of SKG in patients with hemiplegia are common, and different treatment strategies are needed per the individuality of spastic knee extensor activity.

Physical Exercises in Combination with Botulinum Toxin in Treating Children with Cerebral Palsy: A Literature Review

Background

Botulinum Toxin type-A (BoNT-A) is a safe and effective treatment for reducing spasticity in children with cerebral palsy (CP). BoNT-A injection into the muscles alleviate spasticity by interrupting neurotransmission at motor endplate (MEP). Physical activities combined with botulinum injections can help children with CP to become physically independent and improve their health-related quality of life.

Methods

'Botulinum toxin' and 'Physical exercises' for children and adolescents, were searched in three major online databases (PubMed, Science Direct, and Scopus). Through the inclusion and exclusion processes from total 1,233, nine articles were selected for review.

Results

All studies included were experimental trials including various interventions. Botulinum toxins when paired with physical exercises to treat hypertonia, a condition in which a little change in tone can affect a child's balance, strength and motor function, as well as secondary concerns such as malalignment and repair contractures.

Conclusion

BoNT and physical exercises are two promising therapeutic techniques for treating children with CP that enable them for enhancing use and function of their afflicted limb.

The effectiveness of botulinum toxin on spasticity and gait of hemiplegic patients after stroke: A systematic review and meta-analysis

The aim of the study is to evaluate the evidence supporting the efficacy of botulinum toxin type A (BTA) injections in lower limb of hemiplegic patients, after stroke or cerebrovascular accident, and their gait analysis. This study included: randomized controlled trials (RCTs), non-randomized or controlled clinical trials (CCTs) or cluster trials, clinical trials of various phases (I-III), interrupted time series (ITS) studies with at least three data points before and after the intervention, controlled before and after (CBA) studies, prospective and retrospective comparative cohort studies, case-control and multicentred studies. The patients included in these studies had similar characteristics: age over 18 years, history of stroke and following hemiplegia, minimum modified Ashworth scale (MAS) score of 2 and duration since stroke over 6 months. The number of studies included in this review was 21. A meta-analysis was performed on a fraction of them depending on the reported index and the methodology as reported in detail in the results section. MAS score, following BTA injections, was significantly improved (Hedges' g: -1.17; 95% CI: -1.66, 0.67; p < 0.001). The same applied for the 10 Meter Walk Test (MWT) (-0.35; 95% CI: -0.68, -0.02; p = 0.016). The gait velocity showed improvement, yet without statistical significance (0.27; 95% CI: -0.09, 0.63; p = 0.285). We concluded that botulinum toxin injections showed effectiveness on lower limb hypertonia reduction of hemiplegic patients after stroke. Apart from significantly reducing the MAS scores, 10 MWT was also improved. However, more research is required in order to determine the advancement in specific gait and posture parameters.

Do gait parameters improve after botulinum toxin injections in post stroke patients? A prospective study

The intramuscular injection of botulinum toxin is one of the most efficient ways to treat localized spasticity in patients suffering from Central Nervous System lesions like stroke, cerebral palsy and multiple sclerosis. The gait analysis based on kinetics and kinematics is a recognized way of measurement of the effect of intramuscular injection of botulinum toxin in spastic patients suffering from chronic stroke. The aim of this study is to provide evidence of the beneficial effect of botulinum toxin on characteristics of gait pattern on patients suffering from chronic stroke. So, thirteen patients with spasticity due to chronic stroke were included in the protocol and were treated by botulinum toxin injections in the lower extremity. All patients were evaluated before the injection as well as one month after the botulinum injection on a foot pressure sensitive walkway with a power plate and by the readings of seven inertial measurements units which recorded spatio-temporal specific parameters during walking, and the spasticity was measured according to modified Ashworth Scale. While all spatio-temporal parameters of motion analysis and balance improved for most of the patients after botulinum toxin injection, only one parameter, the normal to hemiplegic step length, reached statistical significant improvement (p < 0.03). Moreover the modified Ashworth score was statistically improved post injection (p < 0.001). In conclusion the use of botulinum toxin injections is beneficial in post stroke patients as this is depicted in gait parameters improvement which accompanies the spasticity reduction.

Kinematic and Electrophysiological Characteristics of Pedal Operation by Elderly Drivers during Emergency Braking

Age-related decline in lower limb motor control may cause errors in pedal operation when driving a car. This study aimed to clarify the kinematics and electrophysiological characteristics of the pedal-switching operation associated with emergency braking in the case of elderly drivers. The participants in this study consisted of 11 young drivers and 10 elderly drivers. An experimental pedal was used, and the muscle activity and kinematic data during braking action were analyzed using the light from a light-emitting diode installed in the front as a trigger. The results showed that elderly drivers took the same time from viewing the visual stimulus to releasing the accelerator pedal as younger drivers, but took longer to switch to the brake pedal. The elderly drivers had higher soleus muscle activity throughout the process, from accelerator release to brake contact; furthermore, the rectus femoris activity was delayed, and the simultaneous activity between the rectus femoris and biceps femoris was low. Furthermore, elderly drivers tended to have low hip adduction velocity and tended to switch pedals by hip internal rotation. Thus, the alteration in joint movements and muscle activity of elderly drivers can reduce their pedal operability and may be related to the occurrence of pedal errors.

Adjunct therapies after botulinum toxin injections in spastic adults: systematic review and SOFMER recommendations

BACKGROUND

Adjunct therapies (ATs) may further improve outcomes after botulinum toxin injections in spastic patients, but evidence was unclear in previous systematic reviews.

OBJECTIVE

To assess the efficacy of non-pharmacological ATs in spastic adults according to the International Classification of Functioning, Disability and Health and build an expert consensus based on a Delphi process.

METHODS

Four electronic databases were searched up to May 2020 for reports of comparative trials of non-pharmacologic ATs after botulinum toxin injections in spastic adults. Then 25 French experts participated in a two-round Delphi process to build recommendations on the use of ATs.

RESULTS

We included 32 studies (1202 participants, median 32/study) evaluating the effects of physical agents (n=9), joint posture procedures (JPPs, n=11), and active ATs (n=14), mainly after stroke. The average quality of articles was good for randomised controlled trials (median [interquartile range] PEDro score = 7 [6-8]) but moderate (n=2) or poor (n=2) for non-randomised controlled trials (Downs & Black checklist). Meta-analysis was precluded owing to the heterogeneity of ATs, control groups and outcome measures. There is evidence for the use of JPPs except low-dose manual stretching and soft posture techniques. Continuous postures (by taping or casting) are recommended; discontinuous postures (by orthosis) may be preferred in patients with active function. Device-free or device-assisted active ATs may be beneficial in the mid-term (> 3 months after botulinum toxin injections), particularly when performed at a high intensity (>3 hr/week) as in constraint-induced movement therapy. Self-rehabilitation remains understudied after a focal treatment, but its interest is highlighted by the experts. The use of physical agents is not recommended.

CONCLUSIONS

JPPs and active ATs (device-assisted or device-free) may further improve impairments and activities after botulinum toxin injections. Further studies are needed to better define the best strategies for ATs as a function of the individual treatment goals, participation and quality of life. Review Registration. PROSPERO (CRD42018105856).

Temporal Changes in Electromyographic Activity and Gait Ability during Extended Walking in Individuals Post-Stroke: A Pilot Study

Abnormal gait, particularly in patients with stroke, causes neuromuscular fatigue. We aimed to clarify temporal changes in gait performance and lower limb muscle activity during extended walking in people with stroke hemiplegia. Twelve adults with stroke and eleven healthy controls performed an extended trial involving 20-min continuous walk at a comfortable speed. The primary outcome was electromyography amplitude during the trial and secondary outcomes were walking performance and the instantaneous mean frequency of electromyography during the trial. Data at 1, 6, 12, and 18 min after initiating walking were compared. Performance during extended walking in people with stroke was maintained over time. The electromyography amplitude decreased in the tibialis anterior during the pre-swing phase and increased in the rectus femoris during the single-support phase over time; these changes were similar on the paretic and nonparetic sides. Instantaneous mean frequency decreased over time on the nonparetic side in the tibialis anterior and on the paretic side in the rectus femoris. Healthy subjects did not show any changes over time. The changes in muscle activity in patients with stroke differed between the paretic and nonparetic sides, muscle type, and gait phase; walking performance was maintained despite being affected by neuromuscular fatigue.

Factors Influencing Gait Velocity Improvement Following Botulinum Toxin Injection for Spasticity of the Plantar Flexors in Patients with Stroke

Objective:

In patients with hemiplegia, botulinum toxin type A injection for ankle spasticity of the plantar flexors reportedly improves walking speed. This improvement may be affected by background factors and patient baseline physical performance. This study aimed to clarify the factors affecting gait velocity improvement after botulinum toxin type A injection.

Methods:

Background and evaluation data were collected for 60 patients with stroke who received botulinum toxin type A injection for spasticity of the plantar flexors. The patients were divided into improvement (n=27) and non-improvement (n=33) groups based on the gait velocity change from before injection to 2 weeks after injection. Logistic regression analysis was performed with the improvement and non-improvement groups as response variables and background data and evaluation data at baseline as explanatory variables.

Results:

The presence or absence of physical therapy following botulinum toxin type A injection (odds ratio: 7.82) was the only significant explanatory variable for gait velocity change.

Conclusion:

Background factors and physical performance at baseline did not affect gait velocity improvement after botulinum toxin type A injection. If botulinum treatment of the ankle plantar flexors in patients with stroke is targeted at walking performance improvement, then physical therapy following botulinum toxin type A injection should be an essential part of the treatment strategy.

Pedaling improves gait ability of hemiparetic patients with stiff-knee gait: fall prevention during gait

BACKGROUND AND PURPOSE

Stiff-knee gait, which is a gait abnormality observed after stroke, is characterized by decreased knee flexion angles during the swing phase, and it contributes to a decline in gait ability. This study aimed to identify the immediate effects of pedaling exercises on stiff-knee gait from a kinesiophysiological perspective.

METHODS

Twenty-one patients with chronic post-stroke hemiparesis and stiff-knee gait were randomly assigned to a pedaling group and a walking group. An ergometer was set at a load of 5 Nm and rotation speed of 40 rpm, and gait was performed at a comfortable speed; both the groups performed the intervention for 10 min. Kinematic and electromyographical data while walking on flat surfaces were immediately measured before and after the intervention.

RESULTS

In the pedaling group, activity of the rectus femoris significantly decreased from the pre-swing phase to the early swing phase during gait after the intervention. Flexion angles and flexion angular velocities of the knee and hip joints significantly increased during the same period. The pedaling group showed increased step length on the paralyzed side and gait velocity.

CONCLUSIONS

Pedaling increases knee flexion during the swing phase in hemiparetic patients with stiff-knee gait and improves gait ability.

Botulinum Toxin Therapy Combined with Rehabilitation for Stroke: A Systematic Review of Effect on Motor Function

Aim: The purpose of this study was to examine the effectiveness of botulinum toxin A (BoNT-A) therapy combined with rehabilitation on motor function in post-stroke patients. Methods: The following sources up to December 31, 2018, were searched from inception for articles in English: Pubmed, Scopus, CINAHL, Embase, PsycINFO, and CENTRAL. Trials using injections of BoNT-A for upper and lower limb rehabilitation were examined. We excluded studies that were not performed for rehabilitation or were not evaluated for motor function. Results: Twenty-six studies were included. In addition to rehabilitation, nine studies used adjuvant treatment to improve spasticity or improve motor function. In the upper limbs, two of 14 articles indicated that significant improvement in upper limb motor function was observed compared to the control group. In the lower limbs, seven of 14 articles indicated that significant improvement in lower limb motor function was observed compared to the control group. Conclusions: The effect of combined with rehabilitation is limited after stroke, and there is not sufficient evidence, but results suggest that BoNT-A may help to improve motor function. In future studies, the establishment of optimal rehabilitation and evaluation times of BoNT-A treatment will be necessary for improving motor function and spasticity.

Beyond speed: Gait changes after botulinum toxin injections in chronic stroke survivors (a systematic review)

BACKGROUND

The mechanisms by which spasticity reductions after botulinum toxin A (BoNT) affect gait in stroke are not well understood. We systematically reviewed the effects of BoNT on spatiotemporal, kinematic, kinetic and electromyographic (EMG) measures during gait.

QUESTION

What are the effects of botulinum toxin on gait mechanics in stroke patients?

METHODS

Systematic search using PubMed and Web of Science. We considered all studies that reported laboratory-based and instrumented gait measures as primary or secondary outcomes to determine the effects of BoNT on walking performance in stroke populations only. Selected studies were classified and analysed based on the injection sites.

RESULTS

A total of 240 articles were identified of which 22 were selected for analysis. Overall, 91% of the studies reported spatiotemporal, 64% kinematics, 23% kinetics, 32% EMG and 23% other gait measures. All but one study found significant effects of BoNT on gait measures using instrumented assessments even when clinical measures (i.e. speed) did not significantly improve. However, the majority of the studies had a high risk of bias. Overall, BoNT improved: a) dorsiflexion during stance, propulsive forces and timing and activity of more proximal musculature with injections in the plantarflexors; b) hip, knee and ankle angles and velocities, coordination and energetic cost with injections in the rectus femoris; c) segmental coordination and energetic cost when several lower limb muscles were injected; and, d) elbow and trunk angles when upper limb muscles were injected.

CONCLUSION

Instrumented and laboratory measures of gait improve after BoNT injections in different muscle groups even in the absence of clinical changes.