Perceived impact of spasticity is associated with spatial and temporal parameters of gait in multiple sclerosis

Noninvasive brain stimulation for spasticity rehabilitation in multiple sclerosis: A systematic review of randomized controlled trials

OBJECTIVE

To investigate the effects of noninvasive brain stimulation (NIBS) on spasticity in people with multiple sclerosis (PwMS).

LITERATURE SURVEY

We searched PubMed, SCOPUS, MEDLINE, REHABDATA, PEDro, CINAHL, AMED, and Web of Science until December 2022.

METHODOLOGY

Studies were selected if they included PwMS, used transcranial direct current stimulation (tDCS) or repetitive transcranial magnetic stimulation (rTMS) as a main intervention, and were randomized controlled trials (RCTs) including at least one outcome measure evaluating spasticity. Two researchers individually screened the selected studies. The study's quality was assessed using the Cochrane Collaborations tool. The researchers decided that the meta-analysis was not possible because the treatment interventions varied among the selected studies.

SYNTHESIS

In total, 147 studies were reviewed. Of them, nine studies met the eligibility criteria and included 193 PwMS (mean age = 43.2 years), 54.4% of whom were female. Eight studies were considered "high" quality and one was considered "moderate" quality. Seven studies that used rTMS demonstrated a significant decrease in spasticity in PwMS after the intervention. The remaining studies that provided tDCS did not show meaningful effects.

CONCLUSIONS

The evidence for the influences of rTMS on spasticity in PwMS is promising. The evidence for the impact of tDCS on spasticity in PwMS was limited. Further RCTs with long-term follow-ups are encouraged.

Effects of low vs. high frequency local vibration on mild-moderate muscle spasticity: Ultrasonographical and functional evaluation in patients with multiple sclerosis

BACKGROUND

Local vibration (LV) is a physiotherapy application that aims to reduce spasticity. The study aimed to compare the effects of 50 Hz vs. 100 Hz LV on mild-moderate spasticity, functional performance and muscle architecture.

METHODS

Thirty-three patients were randomly divided into three groups: 50 Hz LV group, 100 Hz LV group and the control group. Physical therapy was applied for one hour a day, three days a week, for a total of eight weeks. LV was applied to the right and left medial gastrocnemius muscles for five minutes. Clinical (spasticity, ankle joint position sense, balance, gait) and ultrasonographic (gastrocnemius fascicle length and pennation angle) measurements were performed before and after treatment.

RESULTS

The study was completed with 27 patients. The decrease in spasticity and the increase in fascicle length were found to be statistically significant in the 50 Hz group (both p<0.05). Ankle joint position sense, single-leg stance time, limits of stability/postural sway range in the medio-lateral direction significantly improved in the vibration treatment groups (all p<0.05). The antero-posterior limits of stability and postural sway showed significant improvement in all groups (all p<0.05). While the 50 Hz group showed significant improvement for all walking parameters; velocity, step length and base of support values improved in the 100 Hz group (all p<0.05). The exercise group showed significant improvement only for single support and stance phase percentages of the gait cycle (both p<0.05). According to between group comparisons, significant difference was found only in medio-lateral limits of stabillity (p<0.05). Medio-lateral limits of stabillity scores were better for the 50 Hz group than the 100 Hz and exercise group.

CONCLUSION

Our findings show that LV does not have any substantial effect except for medio-lateral limits of stability.

CLINICAL TRIAL NUMBER

NCT04192786.

Spasticity, gait, and balance in patients with multiple sclerosis: A cross-sectional study

OBJECTIVE

More than 80% of people with multiple sclerosis (MS) are affected by spasticity. Spasticity is known to reduce quality of life and contribute to additional symptoms, such as pain and reduced mobility, but the association between spasticity, balance, and mobility has not yet been established. Our aim was to examine whether a relationship exists between spasticity in the lower limbs, balance, and gait, as well as to explore the involvement of different muscle groups.

METHODS

This study employed a cross-sectional design. Thirty patients with MS were included. The Modified Ashworth Scale (MAS) was used to examine spasticity in the ankle plantar flexors, knee extensors, and hip adductors. Balance was measured using the Mini-Balance Evaluation Systems Test, and gait with the 2-Minute Walk Test. The participants were tested once with no additional follow-up. Spearman's correlation, recursive partitioning, and linear regression analyses were used to explore the association.

RESULTS

A significant correlation between gait distance and spasticity in the ankle plantar flexors (ρ = -.69, p < .001) and knee extensors (ρ = -.45, p = .012) was observed. Balance significantly correlated with spasticity in ankle plantar flexors (ρ = -.69, p < .001), knee extensors (ρ = -.52, p = .003), and hip adductors (ρ = -.5, p = .005). The relationship between spasticity in ankle plantar flexors and hip adductors was significant, even from low levels of spasticity, whereas MAS score ≥ 2 was clinically correlated with a decrease in gait and balance function. Adjustments for sex, age, or years since diagnosis had only minor impact on the results.

CONCLUSIONS

This study indicates that spasticity in the lower limbs is clinically significantly associated with mobility in people with MS.

The 88-item Multiple Sclerosis Spasticity Scale: a Rasch validation of the Italian version and suggestions for refinement of the original scale

BACKGROUND

In multiple sclerosis (MS), the impact of spasticity on the patient's life is a key issue, and it is fundamental that existing tools measuring the patient's perspective undergo psychometric analysis and refinement to optimize confidence in their use in clinical practice and research.

OBJECTIVE

We examined-by Rasch analysis (RA)-the main metric characteristics of the 88-item Multiple Sclerosis Spasticity Scale (MSSS-88) to: (i) further validate its Italian version (MSSS-88-IT), previously validated through classical test theory methods only and (ii) independently verify the measurement properties of the original scale.

METHODS

MSSS-88 data from a convenience sample of 232 subjects with MS underwent RA, mainly examining item fit, reliability indices, test information function, dimensionality, local item independence, and differential item functioning (DIF).

RESULTS

Most items fitted the Rasch model, but 13/88 items showed a misfit in infit and/or outfit values. Rasch reliability indices were high (> 0.80). Test information functions in most subscales showed a sharp decrease in measurement precision as the ability level departs from the quite limited central range of maximal information. The unidimensionality of each subscale was confirmed. Thirteen item pairs showed local dependency (residual correlations > 0.30) and three items presented DIF.

CONCLUSION

Reliability, dimensionality and some internal construct validity characteristics of the MSSS-88-IT were confirmed. But, drawbacks of the original MSSS-88 emerged related to some item misfit, redundancy, or malfunctioning. Thus, further large independent studies are recommended, to verify the robustness of previous findings and examine the appropriateness of a few targeted item replacements.

The cross-cultural adaptation and psychometric validation of the MSSS-88 for use in Italian patients with multiple sclerosis

PURPOSE

To cross-culturally translate the Multiple Sclerosis Spasticity Scale into Italian and to evaluate its psychometric properties in patients with multiple sclerosis.

METHODS

The Italian version of Multiple Sclerosis Spasticity Scale was developed in accordance with international standards and subsequently administered to 232 Italian adults with multiple sclerosis. The following psychometric properties were analyzed: internal consistency through Cronbach's α and item-to-total correlation, dimensionality with factor analysis, and convergent and criterion validity through hypotheses-testing, comparing the Multiple Sclerosis Spasticity Scale with other outcome measures (Fatigue Severity Scale, Multiple Sclerosis Quality of Life, Modified Ashworth Scale, Barthel Index, and Expanded Disability Status Scale) and analyzing related constructs. Finally, we correlated the MSSS-88 subscales with each other.

RESULTS

The final Multiple Sclerosis Spasticity Scale version was well-understood by all subjects. The internal consistency was good (Cronbach's α ≥0.90). Factor analysis revealed that each subscale was unidimensional. Convergent and criterion validity were supported by acceptable correlations with other disease-specific questionnaires, according to the a priori expectations.

CONCLUSIONS

The final Italian Multiple Sclerosis Spasticity Scale version showed robust psychometric properties. Therefore, it can be recommended as an assessment tool for clinical and research use to evaluate spasticity in Italian patients with multiple sclerosis. Implications for rehabilitation The Multiple Sclerosis Spasticity Scale was developed to measure patients' perception of the impact of spasticity on life of subjects with multiple sclerosis. In a sample of Italian subjects with multiple sclerosis, the Multiple Sclerosis Spasticity Scale revealed good internal consistency and convergent and criterion validity. Factor analysis demonstrated that each subscale was unidimensional. Each subscale can be used to assess the impact of spasticity in Italian patients with multiple sclerosis.

Determinants of botulinum toxin discontinuation in multiple sclerosis: a retrospective study

The purpose of the present study was to investigate the long-term persistence to treatment with botulinum toxin type A (BoNT-A) for multiple sclerosis (MS)-related spasticity and the determinants of BoNT-A discontinuation in daily clinical setting. We retrospectively collected data of patients who started BoNT-A injections and underwent regular follow-up visits. Determinants of BoNT-A discontinuation were explored in a time-to-event Cox regression analysis which included as independent variables a large set of demographic and clinical characteristics. A total of 185 patients started BoNT-A injections from 2002 to 2014 and were followed up to September 2016. Of them, data on 121 were considered in our analysis. At follow-up, 53 (44%) patients were still on treatment and 68 (56%) patients discontinued BoNT-A after a median time of 1.2 years [interval 6 months to 7.4 years]. The reasons for discontinuation were loss of efficacy (n = 45), logistic problems or barriers to reach the structure (n = 16), and adverse events (n = 7). The absence of caregiver (hazard ratio = 1.69, p = 0.03) and lack of regular rehabilitation (hazard ratio = 1.78, p = 0.02) were two independent predictors for BoNT-A discontinuation. Our study confirms the beneficial effect of combining BoNT-A injections with rehabilitation and highlights the crucial role of caregivers for achieving better long-term outcomes in people with MS suffering from spasticity.

Imbalance in multiple sclerosis and neuromyelitis optica: association with deep sensation disturbance

Abnormality in balance is one of the most important causes of gait disturbance which has a direct impact to disability and medical cost in multiple sclerosis (MS) and neuromyelitis optica (NMO). However, characteristics of imbalance in these two diseases have not been fully elucidated. The aim of this study was to evaluate the degree and features of imbalance using stabilography, the degree of deep sensation disturbance using tibial nerve somatosensory evoked potentials (SEP), and their association with clinical impairment, in patients with MS and NMO. Seven NMO patients and seven MS patients with balance disturbance were examined. The relationship among stabilography measurements representing the degree and features of imbalance, height-adjusted P38 peak latency of SEP, and neurological functional disability, were analyzed. Stabilography evaluation showed a significantly severer degree of imbalance in NMO than in MS. Romberg quotient of the patients with brainstem lesions was significantly larger than those without them. In all patients, length of excursion per second significantly correlated positively with anterio-posterior-axis power spectra at intermediate frequency band. In all patients and in NMO, P38 peak latency adjusted by height significantly correlated positively with anterio-posterior-axis power spectra at intermediate frequency band. These findings suggest that the degree of imbalance of MS and NMO possibly correlate with deep sensation disturbance, which could be evaluated by anterio-posterior-axis power spectra at intermediate frequency band by stabilography. Severer imbalance in NMO than MS may be associated with the severe longitudinally extensive spinal cord lesions.

Spasticity in multiple sclerosis and role of glatiramer acetate treatment

INTRODUCTION

Spasticity is one of the most disabling and difficult-to-treat symptoms shown by patients with multiple sclerosis, who often show a suboptimal and unsatisfactory response to classic treatment and new available nonpharmacological alternatives. Due to the progressive nature of this condition, the early management should be essential to improve long-term outcomes.

METHODS

We performed a narrative literature review of the contribution of spasticity to the burden of multiple sclerosis and the potential role of classic disease-modifying drugs.

RESULTS

Added to the underlying pathophysiology of spasticity, certain external factors and drugs such as interferon may exacerbate the existing condition, hence their awareness is crucial as part of an effective management of spasticity. Furthermore, the evidence for the effectiveness of glatiramer acetate in preventing spasticity in naïve patients and in those switching from interferon should not be ignored.

CONCLUSIONS

This literature review proposes the examination of spasticity and the influence of classic disease-modifying agents on the level of existing condition among the variables to be considered when deciding on therapy for multiple sclerosis in clinical practice.

Spatial and temporal characteristics of gait as outcome measures in multiple sclerosis (EDSS 0 to 6.5)

BACKGROUND

Gait impairment represents one of the most common and disabling symptom of multiple sclerosis. Quantification of the gait is an important aspect of clinical trials. In order to identify which temporal or spatial parameters of gait could be used as outcome measures in interventional studies of patients with different levels of disability, we evaluated characteristics of these parameters in MS patients across the whole spectrum of mobility from EDSS 0 to 6.5.

METHODS

This is a cross-sectional study of spatial and temporal parameters of gait at self selected speed and at fast speed of walking in 284 patients with multiple sclerosis (108 men, mean age 38 years ± SD 10.8 years, range 18-64) divided into seven levels of disability (EDSS 0 to 1.5, EDSS 2.0 to 2.5, EDSS 3.0 to 3.5, EDSS 4.0 to 4.5, EDSS 5.0 to 5.5, EDSS 6.0, EDSS 6.5).

RESULTS

The velocity of gait decreases with increasing EDSS levels. Hovewer, the spatio-temporal parameters of gait that are involved in this process differ across the EDSS levels. The step length is decreased at higher EDSS levels up to the EDSS 6.0, but was not different between EDSS 6.0 and 6.5. The step time is significantly longer at EDSS 6.0 and 6.5, while the step length remains the same at those levels. The increase in percentage of double support time becomes statistically significant at EDSS 3.0-3.5 and continues to increase until EDSS 6.5. Variability of step time, step length or step width did not show significant difference between studied EDSS levels.

CONCLUSIONS

There is no single spatio-temporal parameter of gait (other than velocity of gait) that would show significant differences among all levels of EDSS. The step length reflects shortening of steps at lower EDSS levels (2.0 to 6.0), and percentage of double support time better reflects changes at higher EDSS levels 3.0 - 6.5. Gait variability is not associated with disability in MS and therefore would not be a suitable outcome measure. These observations have to be considered when designing gait experiments with temporal and spatial parameters of gait as outcomes.

Plantarflexor weakness negatively impacts walking in persons with multiple sclerosis more than plantarflexor spasticity

OBJECTIVES

To determine whether plantarflexor (PF) spasticity or ankle strength best predicts variance in walking capacity or self-perceived limitations in walking in persons with multiple sclerosis (MS) and whether persons with MS with PF spasticity are weaker and have greater walking dysfunction than do persons with MS without PF spasticity.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PARTICIPANTS

Forty-two adults with MS (mean age, 42.9±10.1y; Expanded Disability Status Scale score, median=3.0, range=0-6) and 14 adults without disability (mean age, 41.9±10.1y).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

PF spasticity and dorsiflexion and PF maximum voluntary isometric torque were assessed using the modified Ashworth Scale and a computerized dynamometer, respectively. The Timed 25-Foot Walk Test was the primary outcome measure of walking capacity. Secondary measures included the 6-Minute Walk Test and the 12-item Multiple Sclerosis Walking Scale.

RESULTS

PF strength was the most consistent predictor of variance in walking capacity (Timed 25-Foot Walk Test: R(2) change=.23-.29, P≤.001; 6-Minute Walk Test: R(2) change=.12-.29, P≤.012), and self-perceived limitations of walking (12-item Multiple Sclerosis Walking Scale: R(2) change=.04-.14, P<.18). There were no significant differences (P>.05) between persons with MS with PF spasticity and persons with MS without PF spasticity for any of the outcome measures.

CONCLUSIONS

Our study suggests a unique contribution of PF weakness to walking dysfunction in persons with MS, and highlights the importance of evaluating PF strength in this clinical population.

Does giving segmental muscle vibration alter the response to botulinum toxin injections in the treatment of spasticity in people with multiple sclerosis? A single-blind randomized controlled trial

Objective:

To determine if segmental muscle vibration and botulinum toxin-A injection, either alone or in combination, reduces spasticity in a sample of patients with multiple sclerosis.

Design:

Single-blind, randomized controlled trial.

Setting:

Physical medicine and rehabilitation outpatients service.

Subjects:

Forty-two patients affected by the secondary progressive form of multiple sclerosis randomized to group A (30 minutes of 120 Hz segmental muscle vibration over the rectus femoris and gastrocnemius medial and lateral, three per week, over a period of four weeks), group B (botulinum toxin in the rectus femoris, gastrocnemius medial and lateral and soleus, and segmental muscle vibration) and group C (botulinum toxin).

Main measures:

Modified Ashworth Scale at knee and ankle, and Fatigue Severity Scale. All the measurements were performed at baseline (T0), 10 weeks (T1) and 22 weeks (T2) postallocation.

Results:

Modified Ashworth Scale at knee and ankle significantly decreased over time ( p < 0.001) in all groups. Patients in group C displayed a significant increase of knee and ankle spasticity at T2 when compared with T1 ( p < 0.05). Fatigue Severity Scale values in groups A and C were significantly higher at T0 [A: 53.6 (2.31); C: 48.5 (2.77)] than at either T1 [A: 48.6 (2.21); p = 0.03; C: 43.5 (3.22); p = 0.03] or T2 [A: 46.7 (2.75); p = 0.02; 42.5 (2.17); p = 0.02], while no differences were detected in group B [T0: 43.4 (3.10); T1: 37.3 (3.15); T2: 39.7 (2.97)].

Conclusion:

Segmental muscle vibration and botulinum toxin-A reduces spasticity and improves fatigue in the medium-term follow-up in patients with multiple sclerosis.

Gait variability and multiple sclerosis

Gait variability, that is, fluctuations in movement during walking, is an indicator of walking function and has been associated with various adverse outcomes such as falls. In this paper, current research concerning gait variability in persons with multiple sclerosis (MS) is discussed. It is well established that persons with MS have greater gait variability compared to age and gender matched controls without MS. The reasons for the increase in gait variability are not completely understood. Evidence indicates that disability level, assistive device use, attentional requirement, and fatigue are related to gait variability in persons with MS. Future research should address the time-evolving structure (i.e., temporal characteristics) of gait variability, the clinical importance of gait variability, and underlying mechanisms that drive gait variability in individuals with MS.

Footfall placement variability and falls in multiple sclerosis

Gait variability (i.e., fluctuations in walking) provides unique information about the control of movement and is associated with falls. This investigation examined the association between gait variability and falls in persons with multiple sclerosis (MS) and healthy controls. Traditional distributional metrics of gait variability (i.e., coefficient of variation (CV)) and a novel metric based on Fourier series analysis of footfall placement variability were determined for 41 individuals with MS and 20 age- and sex-matched controls. Spatiotemporal parameters of gait were collected using a 7.9 m electronic walkway that recorded individual footfalls during steady state comfortable walking. Persons with MS were divided into two groups based on fall history (non-fallers and recurrent fallers). Overall, persons with MS had greater gait variability than controls as indexed by CV and Fourier-based variability (p's < 0.05). Moreover, recurrent fallers with MS had greater Fourier-based variability than non-fallers with MS (p = 0.025), whereas there was no difference in MS groups in traditional gait variability metrics (p > 0.05). These observations highlight that footfall placement variability is related to fall status in MS. Future work determining the sensitivity of footfall placement variability to dysfunction is warranted.