Measuring spasticity and fine motor control (pinch) change in the hand after botulinum toxin-A injection using dynamic computerized hand dynamometry

The Effect of Botulinum Neurotoxin-A (BoNT-A) on Muscle Strength in Adult-Onset Neurological Conditions with Focal Muscle Spasticity: A Systematic Review

Botulinum neurotoxin-A (BoNT-A) injections are effective for focal spasticity. However, the impact on muscle strength is not established. This study aimed to investigate the effect of BoNT-A injections on muscle strength in adult neurological conditions. Studies were included if they were Randomised Controlled Trials (RCTs), non-RCTs, or cohort studies (n ≥ 10) involving participants ≥18 years old receiving BoNT-A injection for spasticity in their upper and/or lower limbs. Eight databases (CINAHL, Cochrane, EMBASE, Google Scholar, Medline, PEDro, Pubmed, Web of Science) were searched in March 2024. The methodology followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was registered in the Prospective Register of Systematic Reviews (PROSPERO: CRD42022315241). Quality was assessed using the modified Downs and Black checklist and the PEDro scale. Pre-/post-injection agonist, antagonist, and global strength outcomes at short-, medium-, and long-term time points were extracted for analysis. Following duplicate removal, 8536 studies were identified; 54 met the inclusion criteria (3176 participants) and were rated as fair-quality. Twenty studies were analysed as they reported muscle strength specific to the muscle injected. No change in agonist strength after BoNT-A injection was reported in 74% of the results. Most studies' outcomes were within six weeks post-injection, with few long-term results (i.e., >three months). Overall, the impact of BoNT-A on muscle strength remains inconclusive.

AbobotulinumtoxinA Doses in Upper and Lower Limb Spasticity: A Systematic Literature Review

Disabling limb spasticity can result from stroke, traumatic brain injury or other disorders causing upper motor neuron lesions such as multiple sclerosis. Clinical studies have shown that abobotulinumtoxinA (AboBoNT-A) therapy reduces upper and lower limb spasticity in adults. However, physicians may administer potentially inadequate doses, given the lack of consensus on adjusting dose according to muscle volume, the wide dose ranges in the summary of product characteristics or cited in the published literature, and/or the high quantity of toxin available for injection. Against this background, a systematic literature review based on searches of MEDLINE and Embase (via Ovid SP) and three relevant conferences (2018 to 2020) was conducted in November 2020 to examine AboBoNT-A doses given to adults for upper or lower limb muscles affected by spasticity of any etiology in clinical and real-world evidence studies. From the 1781 unique records identified from the electronic databases and conference proceedings screened, 49 unique studies represented across 56 publications (53 full-text articles, 3 conference abstracts) were eligible for inclusion. Evidence from these studies suggested that AboBoNT-A dose given per muscle in clinical practice varies considerably, with only a slight trend toward a relationship between dose and muscle volume. Expert-based consensus is needed to inform recommendations for standardizing AboBoNT-A treatment initiation doses based on muscle volume.

The Use of Botulinum Toxin for Treatment of Spasticity

Spasticity is one component of the upper motor neuron (UMN) syndrome resulting from a multitude of neurologic conditions, such as stroke, brain injury, spinal cord injury, multiple sclerosis, and cerebral palsy. It is clinically recognized as a phenomenon of velocity-dependent increase in resistance, i.e., hypertonia. Recent advances in the pathophysiology of spasticity improve our understanding of mechanisms underlying this complex phenomenon and its relations to other components of UMN syndrome (weakness and disordered motor control), as well as the resultant clinical problems. This theoretical framework provides a foundation to set up treatment goals and to guide goal-oriented clinical assessment and treatment. Among a spectrum of treatment options, botulinum toxin (BoNT) therapy is the preferred treatment for focal spasticity. The evidence is very robust that BoNT therapy effectively reduces spasticity; however, it does not improve voluntary movement. In this chapter, we highlight a few issues on how to achieve the best clinical outcomes of BoNT therapy, such as dosing, dilution, guidance techniques, adjunctive therapies, early treatment, repeated injections, and central effects, as well as the ways to improve motor function in selected subgroups of patients with spasticity. We also discuss the reasons of poor responses to BoNT therapy and when not to use BoNT therapy.

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.

Normative Values of the Michigan Hand Outcomes Questionnaire for Patients with and without Hand Conditions

BACKGROUND

The Michigan Hand Outcomes Questionnaire has been widely used for nearly 20 years to assess patients with a variety of hand and upper extremity conditions. However, normative data have not previously been collected, limiting interpretation.

METHODS

The Michigan Hand Outcomes Questionnaire was administered to 579 participants recruited from the general population. In addition, participants were asked to identify any problem affecting their hand(s), including trauma, hand disease/condition, systemic illness, or nonspecific symptoms. Comorbidities and demographic data were also collected.

RESULTS

Total Michigan Hand Outcomes Questionnaire score for healthy individuals was indicative of generally good hand function (95.2; 95 percent CI, 94.3 to 96.1). Individuals with unilateral trauma scored for their affected hand (90.3; 95 percent CI, 87.9 to 92.6) lower than their healthy hand (mean difference, 5.7; 95 percent CI, 3.2 to 8.3). For individuals with and without hand trauma, total Michigan Hand Outcomes Questionnaire score decreased with increasing number of comorbidities. Many of the differences in Michigan Hand Outcomes Questionnaire score between the problem hand and unaffected hand were smaller than the minimal clinically important difference of 3.0 to 23.0 for known abnormalities of the hand and upper extremity.

CONCLUSIONS

These normative data provide appropriate baseline information for individuals with and without underlying hand conditions. Most notably, these findings suggest that individuals with a unilateral problem establish new subnormative values for both their affected and unaffected hands. These data will encourage an appropriate understanding of the results of future studies using the Michigan Hand Outcomes Questionnaire.

A systematic review to investigate the measurement properties of goal attainment scaling, towards use in drug trials

Background

One of the main challenges for drug evaluation in rare diseases is the often heterogeneous course of these diseases. Traditional outcome measures may not be applicable for all patients, when they are in different stages of their disease. For instance, in Duchenne Muscular Dystrophy, the Six Minute Walk Test is often used to evaluate potential new treatments, whereas this outcome is irrelevant for patients who are already in a wheelchair. A measurement instrument such as Goal Attainment Scaling (GAS) can evaluate the effect of an intervention on an individual basis, and may be able to include patients even when they are in different stages of their disease. It allows patients to set individual goals, together with their treating professional. However, the validity of GAS as a measurement instrument in drug studies has never been systematically reviewed. Therefore, we have performed a systematic review to answer two questions: 1. Has GAS been used as a measurement instrument in drug studies? 2: What is known of the validity, responsiveness and inter- and intra-rater reliability of GAS, particularly in drug trials?

Methods

We set up a sensitive search that yielded 3818 abstracts. After careful screening, data-extraction was executed for 58 selected articles.

Results

Of the 58 selected articles, 38 articles described drug studies where GAS was used as an outcome measure, and 20 articles described measurement properties of GAS in other settings. The results show that validity, responsiveness and reliability of GAS in drug studies have hardly been investigated. The quality of the reporting of validity in studies in which GAS was used to evaluate a non-drug intervention also leaves much room for improvement.

Conclusions

We conclude that there is insufficient information to assess the validity of GAS, due to the poor quality of the validity studies. Therefore, we think that GAS needs further validation in drug studies, especially since GAS can be a potential solution when a small heterogeneous patient group is all there is to test a promising new drug.

Trial registration

The protocol has been registered in the PROSPERO international prospective register for systematic reviews, with registration number CRD42014010619. http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42014010619.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-016-0205-4) contains supplementary material, which is available to authorized users.

Validity of the Michigan Hand Outcomes Questionnaire in Patients With Stroke

OBJECTIVE

To investigate the measurement properties of the Dutch version of the Michigan Hand Outcomes Questionnaire (MHQ) in patients with stroke.

DESIGN

Validation study.

SETTING

Outpatient rehabilitation clinic.

PARTICIPANTS

Consecutive patients with stroke (N=51; mean age, 60±11y; 16 women [31%]).

INTERVENTIONS

Patients were asked to complete the MHQ (57 items) and Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Additional assessments included the Barthel Index and performance tests for hand function (Action Research Arm Test, Nine Hole Peg Test, Frenchay Arm Test, Motricity Index).

MAIN OUTCOME MEASURES

Associations between the MHQ and other outcome measures were determined using Spearman correlation coefficients and the internal consistency of the MHQ using Cronbach α. Floor or ceiling effects were present if >15% of the patients scored minimal or maximal scores, respectively. Test-retest reliability was established by the intraclass correlation coefficient.

RESULTS

The mean MHQ total score was 70.0±22.4, with Cronbach α being .97. The MHQ total score correlated significantly with the physical component summary of the SF-36, the Barthel Index, and all hand function performance tests (P<.01). The MHQ total score showed no floor or ceiling effects. The test-retest intraclass correlation coefficient was .97.

CONCLUSIONS

This study provides preliminary evidence that the MHQ is an internally consistent, valid, and reliable hand function questionnaire in outpatients after stroke, although these results need to be further confirmed.