Does botulinum toxin treatment improve upper limb active function?

Long-Term Management of Post-Stroke Spasticity with Botulinum Toxin: A Retrospective Study

Stroke-induced spasticity is a prevalent condition affecting stroke survivors, significantly impacting their quality of life. Botulinum Toxin A injections are widely used for its management, yet the long-term effects and optimal management strategies remain uncertain. This retrospective study analyzed medical records of 95 chronic stroke patients undergoing long-term BoNT-A treatment for spasticity. Demographic data, treatment duration, dosage variability, and dropout rates were assessed over a period ranging from 2 to 14 years. The study revealed a notable extension of the interval between BoNT-A injections throughout the treatment duration. Dropout rates peaked during the initial 5 years of treatment, perhaps due to perceived treatment ineffectiveness. Additionally, a trend of escalating dosage was observed across all groups, indicating a potential rise in the severity of spasticity or changes in treatment response over time. BoNT-A injections emerged as the predominant treatment choice for managing post-stroke spasticity. The delayed initiation of BoNT-A treatment underscores the need for heightened awareness among healthcare providers to recognize and manage spasticity promptly post-stroke. Patients' expectations and treatment goals should be clearly defined to optimize treatment adherence, while the observed escalation in dosage and treatment intervals emphasizes the dynamic nature of spasticity and underscores the importance of monitoring long-term treatment outcomes.

Peripheral nerve blocks of wrist and finger flexors can increase hand opening in chronic hemiparetic stroke

Introduction

Hand opening is reduced by abnormal wrist and finger flexor activity in many individuals with stroke. This flexor activity also limits hand opening produced by functional electrical stimulation (FES) of finger and wrist extensor muscles. Recent advances in electrical nerve block technologies have the potential to mitigate this abnormal flexor behavior, but the actual impact of nerve block on hand opening in stroke has not yet been investigated.

Methods

In this study, we applied the local anesthetic ropivacaine to the median and ulnar nerve to induce a complete motor block in 9 individuals with stroke and observed the impact of this block on hand opening as measured by hand pentagonal area. Volitional hand opening and FES-driven hand opening were measured, both while the arm was fully supported on a haptic table (Unloaded) and while lifting against gravity (Loaded). Linear mixed effect regression (LMER) modeling was used to determine the effect of Block.

Results

The ropivacaine block allowed increased hand opening, both volitional and FES-driven, and for both unloaded and loaded conditions. Notably, only the FES-driven and Loaded condition's improvement in hand opening with the block was statistically significant. Hand opening in the FES and Loaded condition improved following nerve block by nearly 20%.

Conclusion

Our results suggest that many individuals with stroke would see improved hand-opening with wrist and finger flexor activity curtailed by nerve block, especially when FES is used to drive the typically paretic finger and wrist extensor muscles. Such a nerve block (potentially produced by aforementioned emerging electrical nerve block technologies) could thus significantly address prior observed shortcomings of FES interventions for individuals with stroke.

Neurophysiological and clinical outcome measures of the impact of electrical stimulation on spasticity in spinal cord injury: Systematic review and meta-analysis

This systematic review and meta-analysis aims to determine whether non-invasive electrical stimulation (ES) is effective at reducing spasticity in people living with spinal cord injury (SCI). PubMed, Web of Science, Scopus and Cochrane Central Register of Controlled Trials databases were searched in April 2022. Primary outcome measures were the Ashworth scale (AS), Modified Ashworth scale (MAS), Pendulum test and the Penn spasm frequency scale (PSFS). Secondary outcomes were the Hoffman (H)- reflex, motor-evoked potentials (MEPs) and posterior-root reflexes (PRRs). A random-effects model, using two correlation coefficients, ( C o r r = 0.1 , C o r r = 0.2 ) determined the difference between baseline and post-intervention measures for RCTs. A quantitative synthesis amalgamated data from studies with no control group (non-RCTs). Twenty-nine studies were included: five in the meta-analysis and 17 in the amalgamation of non-RCT studies. Twenty studies measured MAS or AS scores, 14 used the Pendulum test and one used the PSFS. Four measured the H-reflex and no studies used MEPs or PRRs. Types of ES used were: transcutaneous electrical nerve stimulation (TENS), transcutaneous spinal cord stimulation (TSCS), functional electrical stimulation (FES) cycling and FES gait. Meta-analyses of 3 studies using the MAS and 2 using the Pendulum test were carried out. For MAS scores, non-invasive ES was effective at reducing spasticity compared to a control group (p = 0.01, C o r r = 0.1 ; p = 0.002, C o r r = 0.2 ). For Pendulum test outcomes, there was no statistically significant difference between intervention and control groups. Quantitative synthesis of non-RCT studies revealed that 22 of the 29 studies reported improvement in at least one measure of spasticity following non-invasive ES, 13 of which were statistically significant (p < 0.05). Activation of the muscle was not necessary to reduce spasticity. Non-invasive ES can reduce spasticity in people with SCI, according to MAS scores, for both RCT and non-RCT studies, and Pendulum test values in non-RCT studies. This review could not correlate between clinical and neurophysiological outcomes; we recommend the additional use of neurophysiological outcomes for future studies. The use of TSCS and TENS, which did not induce a muscle contraction, indicate that activation of afferent fibres is at least required for non-invasive ES to reduce spasticity.

Goal-Setting in Multiple Sclerosis-Related Spasticity Treated with Botulinum Toxin: The GASEPTOX Study

Spasticity is one of the most disabling symptoms in multiple sclerosis (MS). Botulinum toxin injection (BTI) is a first-line treatment for focal spasticity. There is a lack of evidence of a functional improvement following BTI in MS-related spasticity. To describe goal-setting for BTI in MS, and evaluate the degree of attainment, using goal attainment scaling (GAS) 4-to-6 weeks after injection session, a one-year multi-center retrospective observational study assessing goal-setting and achievement during BTI session in spastic patients with MS was set up. Following the GAS method, patients and their physicians set up to three goals and scored their achievement 4 to 6 weeks thereafter. Commonly used goals from three centers were combined into a standardized list and 125 single BTI sessions were analyzed. The most frequent goals regarded lower limb (LL) impairments (equinovarus foot, toe claw) or locomotion (stability, walking distance, clinging) and accounted for 89.1%, versus 10.9% for upper limb (UL), mostly for mild-to-moderate MS. Overall, goals were frequently achieved (85.77%) mainly when related to gait and mobility rather than hygiene and ease of care. This study gives an overview on the most frequent, relevant, and achievable goals to be set in real-life practice of BTI for spasticity management in MS.

Predictors of Clinically Important Improvements in Motor Function and Daily Use of Affected Arm after a Botulinum Toxin A Injection in Patients with Chronic Stroke

Identifying patients who can gain minimal clinically important difference (MCID) in active motor function in the affected upper extremity (UE) after a botulinum toxin A (BoNT-A) injection for post-stroke spasticity is important. Eighty-eight participants received a BoNT-A injection in the affected UE. Two outcome measures, Fugl–Meyer Assessment Upper Extremity (FMA-UE) and Motor Activity Log (MAL), were assessed at pre-injection and after 24 rehabilitation sessions. We defined favorable response as an FMA-UE change score ≥5 or MAL change score ≥0.5.Statistical analysis revealed that the time since stroke less than 36 months (odds ratio (OR) = 4.902 (1.219–13.732); p = 0.023) was a significant predictor of gaining MCID in the FMA-UE. Medical Research Council scale -proximal UE (OR = 1.930 (1.004–3.710); p = 0.049) and post-injection duration (OR = 1.039 (1.006–1.074); p =0.021) were two significant predictors of MAL amount of use. The time since stroke less than 36 months (OR = 3.759 (1.149–12.292); p = 0.028), naivety to BoNT-A (OR = 3.322 (1.091–10.118); p = 0.035), and education years (OR = 1.282 (1.050–1.565); p = 0.015) were significant predictors of MAL quality of movement. The findings of our study can help optimize BoNT-A treatment planning.

Passive Properties of the Wrist and Fingers Following Chronic Hemiparetic Stroke: Interlimb Comparisons in Persons With and Without a Clinical Treatment History That Includes Botulinum Neurotoxin

Background: Neural impairments that follow hemiparetic stroke may negatively affect passive muscle properties, further limiting recovery. However, factors such as hypertonia, spasticity, and botulinum neurotoxin (BoNT), a common clinical intervention, confound our understanding of muscle properties in chronic stroke. Objective: To determine if muscle passive biomechanical properties are different following prolonged, stroke-induced, altered muscle activation and disuse. Methods: Torques about the metacarpophalangeal and wrist joints were measured in different joint postures in both limbs of participants with hemiparetic stroke. First, we evaluated 27 participants with no history of BoNT; hand impairments ranged from mild to severe. Subsequently, seven participants with a history of BoNT injections were evaluated. To mitigate muscle hypertonia, torques were quantified after an extensive stretching protocol and under conditions that encouraged participants to sleep. EMGs were monitored throughout data collection. Results: Among participants who never received BoNT, no significant differences in passive torques between limbs were observed. Among participants who previously received BoNT injections, passive flexion torques about their paretic wrist and finger joints were larger than their non-paretic limb (average interlimb differences = +42.0 ± 7.6SEM Ncm, +26.9 ± 3.9SEM Ncm, respectively), and the range of motion for passive finger extension was significantly smaller (average interlimb difference = -36.3° ± 4.5°SEM; degrees). Conclusion: Our results suggest that neural impairments that follow chronic, hemiparetic stroke do not lead to passive mechanical changes within the wrist and finger muscles. Rather, consistent with animal studies, the data points to potential adverse effects of BoNT on passive muscle properties post-stroke, which warrant further consideration.

Can Incobotulinumtoxin-A Treatment Improve Quality of Life Better Than Conventional Therapy in Spastic Muscle Post-Stroke Patients? Results from a Pilot Study from a Single Center

Post-stroke spasticity frequently occurs in patients with stroke, and there is a need for more quality-of-life assessments for different therapies. We evaluated for the first time in Romania the quality of life among patients with post-stroke spasticity, comparing two therapies over a 6-month period: botulinum toxin type A (BOT) with conventional therapy (CON). We also assessed the reduction of spasticity and functionality secondary to the increase in the mobility in upper limbs. This study was based on a prospective, randomized design, including subjects with post-stroke spasticity (N = 34; 34–80 years of age): in the CON arm, patients received therapy against muscle spasticity and physiotherapy, and, in the BOT arm, patients received incobotulinumtoxin-A and additionally conventional treatment, if required. Among 34 treated subjects in the two arms, the quality of life was significantly higher after BOT therapy (p < 0.001), represented by improvement in movement (p < 0.001), usual activities (p = 0.018), and distress (p < 0.001). Improvements in muscle tone (Ashworth Scale) over 6 months of treatment period were greater in the BOT arm (100%) than in the CON arm (11.8%). These preliminary results suggested that incobotulinumtoxin-A increased quality of life by improving movement, daily activities, mental health, and muscle tone more effectively than conventional therapy and could form a basis for future comparator studies.

Long-term effects of combined botulinum toxin treatment and rehabilitation on upper limb muscle spasms: a case report

[Purpose] We report our experience with a patient with a central spinal cord injury who showed improved finger and upper limb functions after long-term treatment with a combination of rehabilitation and botulinum toxin type A. [Participants and Methods] The patient had spasms and pain that gradually became more profound and was given botulinum toxin type A at 1 year 3 months after sustaining a spinal cord injury. We administered 14 botulinum toxin type A injections periodically for 7 years 4 months after the injury. We administered the injections at an average interval of 5.6 months. Splints that allowed extension and improved finger muscle tone and contracture were made for the patient. [Results] The patient experienced gradual alleviation of the spasms in the proximal upper limb muscles and improved range of motion after receiving five doses of botulinum toxin type A. The spasms and range of motion in the fingers gradually improved around 4 years after the injury through splint therapy and a combination of botulinum toxin type A administration and rehabilitation. [Conclusion] The combination of botulinum toxin type A, splint, and rehabilitation therapies can lead to positive improvements in finger spasticity and range of motion and is recommended for hypertonia cases with severe contractures.

Self-rehabilitation combined with botulinum toxin to improve arm function in people with chronic stroke. A randomized controlled trial

BACKGROUND

Botulinum toxin injection (BTI) reduces muscle hyperactivity, but its effect on active upper-limb function is limited. Intensive rehabilitation could optimize the effects; however, outpatient post-stroke rehabilitation is usually not intensive. One solution could be self-rehabilitation.

OBJECTIVES

The aim of this randomized controlled trial was to determine the effect of a self-rehabilitation program combined with BTI on upper-limb function in individuals with chronic hemiparesis.

METHODS

In total, 33 outpatients were randomly allocated to receive BTI+self-rehabilitation (R group: n=17) or BTI alone (C group: n=16). Outcomes evaluated just before the BTI and 4 weeks later included the Wolf Motor Function Test (WMFT time: primary outcome), Action Research Arm Test, fatigue and quality of life.

RESULTS

Change in WMFT did not differ between groups at 4 weeks (WMFT time: -14% for R group, -4% for C group. WFMT score: +12% for R group, 0% in C group). WFMT time and score improved significantly in the R group only (-14%, P=0.01, and +12%, P=0.02). In addition, the proportion of patients with improved WMFT time and score was higher in the R than C group (R group: 71% improved score, 77% improved time; C group: 43% improved score, 50% improved time). Also, passive range of shoulder flexion (P=0.03) and wrist extension (P=0.01) improved only in the R group. No other variables changed significantly. Compliance was excellent; average daily training time was greater than that prescribed.

CONCLUSIONS

The addition of a self-rehabilitation program to BTI did not significantly improve functional outcomes more than BTI alone; however, movement quality and speed improved only in the self-rehabilitation group. Participants in the self-rehabilitation group trained more than they were asked to, which suggests that they found the program worthwhile. These clinically relevant findings justify larger-scale studies of the effects of self-rehabilitation to enhance the effects of BTI.

CLINICAL TRIAL

NCT02699762.

Rehabilitation Treatment of Motor Dysfunction Patients Based on Deep Learning Brain-Computer Interface Technology

In recent years, brain-computer interface (BCI) is expected to solve the physiological and psychological needs of patients with motor dysfunction with great individual differences. However, the classification method based on feature extraction requires a lot of prior knowledge when extracting data features and lacks a good measurement standard, which makes the development of BCI. In particular, the development of a multi-classification brain-computer interface is facing a bottleneck. To avoid the blindness and complexity of electroencephalogram (EEG) feature extraction, the deep learning method is applied to the automatic feature extraction of EEG signals. It is necessary to design a classification model with strong robustness and high accuracy for EEG signals. Based on the research and implementation of a BCI system based on a convolutional neural network, this article aims to design a brain-computer interface system that can automatically extract features of EEG signals and classify EEG signals accurately. It can avoid the blindness and time-consuming problems caused by the machine learning method based on feature extraction of EEG data due to the lack of a large amount of prior knowledge.

The Effects of Botulinum Toxin Injections on Spasticity and Motor Performance in Chronic Stroke with Spastic Hemiplegia

Spastic muscles are weak muscles. It is known that muscle weakness is linked to poor motor performance. Botulinum neurotoxin (BoNT) injections are considered as the first-line treatment for focal spasticity. The purpose of this study was to quantitatively investigate the effects of BoNT injections on force control of spastic biceps brachii muscles in stroke survivors. Ten stroke survivors with spastic hemiplegia (51.7 ± 11.5 yrs; 5 men) who received 100 units of incobotulinumtoxinA or onabotulinumtoxinA to the biceps brachii muscles participated in this study. Spasticity assessment (Modified Ashworth Scale (MAS) and reflex torque) and muscle strength of elbow flexors, as well as motor performance assessment (force variability of submaximal elbow flexion) were performed within one week before (pre-injection) and 3~4 weeks (3-wk) after BoNT injections. As expected, BoNT injections reduced the MAS score and reflex torque, and elbow flexor strength on the spastic paretic side. However, motor performance remained within similar level before and after injections. There was no change in muscle strength or motor performance on the contralateral arm after BoNT injections. The results of this study provide evidence that BoNT injections can reduce spasticity and muscle strength, while motor performance of the weakened spastic muscle remains unchanged.

Non-invasive treatment of patients with upper extremity spasticity following stroke using paired trans-spinal and peripheral direct current stimulation

Background

Muscle spasticity is a common impediment to motor recovery in patients with chronic stroke. Standard-of-care treatments such as botulinum toxin injections can temporarily relieve muscle stiffness and pain associated with spasticity, but often at the expense of increased muscle weakness. Recent preclinical investigations of a non-invasive treatment that pairs trans-spinal direct current stimulation and peripheral nerve direct current stimulation (tsDCS+pDCS) provided promising data for a novel approach based on bioelectronic medicine for the treatment of patients with post-stroke spasticity.

Methods

Twenty-six patients with upper limb hemiparesis and wrist spasticity at least 6 months after their initial stroke participated in this single-blind crossover design study to test whether tsDCS+pDCS reduces chronic upper-extremity spasticity. Subjects received five consecutive daily sessions (20 min of stimulation or sham) of anodal tsDCS+pDCS, separated by a one-week washout period. The sham condition always preceded the active condition. Clinical and objective measures of spasticity and motor function were collected before and after each condition, and for five weeks after the completion of the active intervention.

Results

Subjects treated with active tsDCS+pDCS demonstrated significant reductions in both Modified Tardieu Scale scores (summed across the upper limb, P < 0.05), and in objective torque measures (Nm) of the spastic catch response at the wrist flexor (P < 0.05), compared to the sham condition. Motor function also improved significantly (measured by the Fugl-Meyer and Wolf Motor Function Test; P < 0.05 for both tests) after active treatment.

Conclusions

tsDCS+pDCS intervention alone significantly reduced upper limb spasticity in participants with stroke. Decreased spasticity was persistent for five weeks after treatment, and was accompanied by improved motor function even though patients were unsupervised and there was no prescribed activity or training during that interval.

Trial registration

NCT03080454, March 15, 2017.