Construct Validity of the Four Square Step Test in Multiple Sclerosis

No immediate change in systemic cytokines following an eccentric muscle training session in people with multiple sclerosis

Background

Eccentric muscle contractions elicit distinct physiological responses, including modulation of the cytokine profile. Although relevant for rehabilitation, the effect of eccentric muscle training on the immune system has never been investigated in multiple sclerosis (MS).

Objectives

Examine the immediate cytokine response of interleukin-4 (IL-4), IL-6, IL-10, IL-17a, interferon-gamma, and tumor necrosis factor-alpha after a moderate eccentric training session in individuals with MS. Additionally, further investigate the association between systemic cytokine levels at rest and clinical measures of mobility and lower limb functional strength.

Design

Observational study.

Methods

The first session included blood sampling for baseline cytokine measures. Subsequently, the participant completed a battery of clinical assessments related to mobility and lower limb strength, that is, the Timed-Up-and-Go Test, Five-Repetition-Sit-to-Stand-Test (5STS), Four-Square-Step-Test, and Two-Minute-Walk-Test. The second session included the eccentric exercise training session, followed by a second blood sampling to assess the acute cytokine response to the eccentric training bout. This session comprised 10 exercises concentrating on the strength of the trunk and lower extremities.

Results

Twenty-seven people with MS (pwMS), with a mean age of 40.1 years, participated in the study. No difference was demonstrated in the cytokine concentration values between baseline and immediately after the eccentric training session. The 5STS explained 30.3% of the variance associated with interferon-gamma, 14.8% with IL-4, and 13.8% with IL-10.

Conclusion

An eccentric training bout does not impact cytokine concentration in the blood and, consequently, does not boost a pro-inflammatory response, thus, it can be performed on pwMS in a rehabilitation setting.

The association of fear of falling and falls with sedentary behavior in people with multiple sclerosis

OBJECTIVE

Sedentary behavior, falls, and fear of falling (FoF) are specific concerns for people with MS (pwMS). Considering the relatively high incidence and potential linkage, it is surprising that this triple relationship has as yet not been extensively investigated in pwMS. Thus, the present study aimed to examine the correlates of sedentary behavior with FoF and falls in pwMS.

METHODS

Fifty pwMS, 30 women, were admitted to this cross-sectional study. Primary outcome measures included physical activity and sedentary behavior metrics measured by accelerometry, fall status, and FoF. Additional measures included mobility clinical tests, cognition, perceived fatigue, depression, and anxiety. The sample was divided into two subgroups according to the daily Metabolic Equivalent of Task (MET) rate scores; <1.5 was defined as sedentary, ≥1.5 were defined as non-sedentary. Multivariate analysis of variance and linear regression analyses assessed the relationships by using an alpha of 0.05.

RESULTS

Sixty-four percent of the sample were classified as sedentary. The sedentary subgroup reported more FoF than the non-sedentary subgroup (32.5 (S·D. = 11.3) vs. 29.9 (S.D. = 9.5); however, no differences were found in fall status between the subgroups. No differences were found for depression, anxiety, cognition, and perceived fatigue between the subgroups. Furthermore, according to the linear regression analysis, FoF explained 23.9% of the variance pertaining to the daily MET rate when controlling for age, gender, disease duration, and disability.

CONCLUSIONS

Clinicians are encouraged to incorporate the issue of FoF during standard management, which may represent an opportunity to improve care and reduce sedentary behavior in pwMS.

The relationship between visual function and physical performance in the Study of Muscle, Mobility and Aging (SOMMA)

PURPOSE

The relationship of types of visual function to different aspects of physical function, especially strength and coordination, has been understudied, but delineation of these relationships could suggest potentially modifiable targets prior to the onset of disability.

METHODS

Cross-sectional analysis of visual function (self-reported eyesight and eye disease, visual acuity, contrast sensitivity) and physical function tests in 877 older adults (mean age 76.36±5.01 years, 59.2% women, and 13.3% Black race). Separate linear regression models were constructed for short physical performance battery (SPPB), expanded SPPB (eSPPB), their components (gait speed, chair stand, balance, narrow walk), stair climb, four-square step, leg extension peak power and strength, and grip strength.

RESULTS

In adjusted models, worse acuity, worse contrast sensitivity, and self-reported poor vision were significantly associated with worse performance on the eSPPB and four-square step test. Worse contrast sensitivity, but not acuity, was significantly associated with shorter balance times, slower chair stand pace, longer stair climb time, and worse SPPB score. Associations of worse acuity and contrast sensitivity with weaker leg extension power, leg strength, and grip strength were attenuated by covariate adjustment. Self-reported macular degeneration, but not cataract or glaucoma, was associated with worse performance on SPPB, eSPPB, balance, stair climb, and four-square step tests in adjusted models. Worse contrast sensitivity and macular degeneration remained associated with worse SPPB and balance after controlling for visual acuity and self-reported eyesight.

CONCLUSIONS

Poor contrast sensitivity was more strongly associated with worse physical performance than acuity, especially for complex tasks that dynamically challenge coordination and balance. Future studies should examine if older adults with contrast sensitivity impairment would benefit from targeted intervention to decrease their risk of disability.

Embodied learning in multiple sclerosis using melodic, sound, and visual feedback: a potential rehabilitation approach

Given the prevalence of motor and cognitive functions in persons with multiple sclerosis (PwMS), we proposed that the theoretical framework of embodiment could provide a rehabilitation avenue to train these functions as one functional unit. PwMS (n = 31) and age- and gender-matched healthy controls (n = 30) underwent an embodied learning protocol. This involved learning a cognitive sequence while performing it through bodily stepping movement under three feedback conditions (melody, sound, and visual). Cognitive and movement performance was assessed by a delayed recall 15 min after undergoing the embodied learning protocol. Half of participants correctly recalled the sequence in all three conditions, while 70% of healthy controls achieved correct recall within the melody condition. Balance impairment predicted the speed of executing the sequence irrespective of learning, most apparent in the melody condition. Information processing speed predicted the speed of executing the sequence in the melody and sound conditions between participants as well as over time. Those who learned performed the sequence faster in the melody condition only and overall were faster over time. We propose how embodied learning could expand the current context of rehabilitation of cognitive and motor control in PwMS.

Motor sequence learning in a goal-directed stepping task in persons with multiple sclerosis: a pilot study

Motor sequence learning in persons with multiple sclerosis (pwMS) and healthy controls (HC) under implicit or explicit learning conditions has not yet been investigated in a stepping task. Given the prevalent cognitive and mobility impairments in pwMS, this is important in order to understand motor learning processes and optimize rehabilitation strategies. Nineteen pwMS (the Expanded Disability Status Scale = 3.4 ± 1.2) and 18 HC performed a modified serial reaction time task by stepping as fast as possible on a stepping tile when it lit up, either with (explicit) or without (implicit) knowledge of the presence of a sequence beforehand. Motor sequence learning was studied by examining response time changes and differences between sequence and random blocks during the learning session (acquisition), 24 h later (retention), and in three dual-task (DT) conditions at baseline and retention (automaticity) using subtracting sevens, verbal fluency, and vigilance as concurrent cognitive DTs. Response times improved and were lower for the sequenced compared with the random blocks at the post- and retention tests (P's < 0.001). Response times during DT conditions improved after learning, but DT cost improved only for the subtracting sevens DT condition. No differences in learning were observed between learning conditions or groups. This study showed motor sequence learning, by acquisition and retention, in a stepping task in pwMS with motor impairments, to a similar degree as HC and regardless of learning conditions. Whether automaticity increased remains unclear.

Enhancement of balance, and mobility in individuals with multiple sclerosis using visual cue guided multidirectional step training - A pilot study

BACKGROUND

Individuals with multiple sclerosis (MS) often experience limitations in mobility due to impairment of gait and balance. Rehabilitation approaches to improve balance and mobility in individuals with MS are limited. We have developed a novel visual cue guided multi-direction step (MDS) training method to improve balance and mobility in individuals with MS.

OBJECTIVE

To examine the effect of MDS training on balance, gait, and mobility in individuals with MS.

METHODS

Five individuals with relapsing- remitting MS participated in the 4-week training involving stepping in eight directions in response to a visual cue. Balance, gait, and mobility were assessed before and after training.

RESULTS

Training related improvements were seen in the limits of stability (p< .05), spatial and temporal gait parameters (p<.05), and performance of the Tinetti Mobility Assessment (p=.001), 10-Meter Walk test (p<.001), and Four-Square Step test (p<.002).

CONCLUSION

Balance, gait, and mobility in individuals with MS could be improved after 4 weeks of visual cue guided multi-direction stepping training. Outcomes from this feasibility study could help to refocus conventional rehabilitation strategies aimed at aiding individuals with MS to achieve maximal independence in mobility.

The association between bladder dysfunction, balance and falls in women with multiple sclerosis: The specific contribution of fear of falling

BACKGROUND

Bladder dysfunction is the most common autonomic disturbance in people with MS (PwMS). Only a few studies have examined the relationship between bladder dysfunction and falls in PwMS. Bladder dysfunction has been deemed only a secondary outcome measure, and classified by a gross measure providing a limited perspective of this disturbing symptom. Furthermore, no study to date has focused on the relationship between bladder dysfunction and balance performance in PwMS.

RESEARCH QUESTION

Determine the relationship between bladder dysfunction with balance, falls and fear of falling in women with MS.

METHODS

The study was observational, including 44 women with MS, mean age 46.3 (SD = 5.7), all with at least a mild bladder dysfunction. Outcome measures included the Urinary Incontinence Quality of Life Scale (I-QoL), Bladder Control Scale (BLCS), Timed Up and Go Test (TUG), Four Square Step Test (FSST), Falls Efficacy Scale International (FES-I), Falls status, and posturography.

RESULTS

Participants performed the TUG in 14.1 s (S.D. = 11.1), and the FSST in 20.5 s (S.D. = 22.4). A relatively large proportion (68.2 %) of women was classified as fallers. However, no differences were found between those classified as fallers (n = 30) or non-fallers (n = 14) in terms of the I-QoL and the BLCS, controlling for age, EDSS and number of vaginal deliveries. Significant correlations scores were found between the I-QoL, BLCS and FES-I (rho ∼0.47), while controlling for age, EDSS and number of vaginal deliveries. No associations were demonstrated between the bladder dysfunction outcome scores and either the TUG and/or FSST.

SIGNIFICANCE

Women afflicted with MS and suffering from bladder dysfunction tend to fall and present with more balance difficulties compared with disability-matched PwMS. Nevertheless, once bladder dysfunction is detected, the perceived severity of the condition is not associated with balance and prevalence of falling, but rather on fear of falling.

The Four Square Step Test for Assessing Cognitively Demanding Dynamic Balance in Parkinson's Disease Patients

Objective

The Four Square Step Test (FSST) is a tool that assesses dynamic balance during obstacle step-over. To date, few studies have used the FSST to measure balance in patients with Parkinson’s disease (PD). This study aimed to verify that patients with PD, even at the de novo early stage, take more time to perform the FSST and identify which factors, cognitive status or cardinal motor symptoms, are related most to FSST scores.

Methods

Thirty-five newly diagnosed drug-naïve patients with PD and 17 controls completed the FSST. The Unified Parkinson’s Disease Rating Scale (UPDRS), Hoehn and Yahr (H&Y) stage, spatiotemporal gait parameters, and neuropsychological test battery were also assessed in the PD group.

Results

Mean FSST performance time was 8.20 ± 1.61 seconds in patients with PD, which was significantly more than the control group (7.13 ± 1.10 seconds, p = 0.018). UPDRS part III total score and H&Y stage were not significantly associated with FSST, but among the UPDRS subscores, only the postural instability/gait disturbance subscore showed a significant association. Regarding the association between FSST and cognition, the Trail Making Test-B and the Color Word Stroop Test showed strongly inverse correlations with FSST (rho = -0.598 and -0.590, respectively). With respect to gait parameters, double support time was significantly associated with FSST score (rho = 0.342, p = 0.044); however, other parameters, including velocity and step length, were not associated with the FSST.

Conclusion

The FSST can be used in the clinic to assess dynamic balance with cognitive demands even in the early stages of PD.

Description of novel instrumented analysis of the Four Square Step Test with clinical application: A pilot study

BACKGROUND

Falls are a common problem for adults in the United States raising concerns about injuries and the resulting economic burden. As a result, it is critical to develop objective measures to assess dynamic balance and the track progress related to interventions or disease progression over time.

RESEARCH QUESTION

Are there differences in balance between individuals in the community, individuals post-stroke, persons with Multiple Sclerosis (MS), and individuals living with Parkinson's Disease (PD) as measured with a new instrumented Four Square Step Test (i-FSST)?

METHODS

The i-FSST was utilized to assess dynamic balance in 41 individuals (11 community dwelling adults and 10 individuals in each group of persons post stroke, with PD, and with MS). Outcome data including the overall duration of the FSST as well unique temporal-spatial stepping patterns through the test, timing of transitions between each quadrant, and the time in each quadrant prior to transitioning.

RESULTS

One-way ANOVAs were conducted to determine whether i-FSST duration, Over Double Support (ODS), and Changes in Main Support (CMS) differed by participants' groups. There was a significant difference between groups in test Duration (F = 9.56, P =  .000), ODS (F = 15.71, P =  .001), and CMS (F = 7.03, P =  .001). Further differences in these variables were found between various groups using Bonferroni post-hoc testing.

SIGNIFICANCE

The i-FSST is an innovative and potentially beneficial tool for quantitatively measuring the dynamics that occur in the traditional FSST including a general measure of dynamic balance as well as transition times and stability during the test. This technology can provide objective data on stability, weight shifting, and weight acceptance that may guide interventions and further assessment.

Improving our understanding of the most important items of the Multiple Sclerosis Walking Scale-12 indicating mobility dysfunction: Secondary results from a RIMS multicenter study

BACKGROUND

The 12-item Multiple Sclerosis Walking Scale (MSWS-12) is currently the most widely validated, patient-reported outcome measure assessing patients' perception of the impact of multiple sclerosis (MS) on walking ability. To date, the majority of previous studies investigating the MSWS-12 have focused on the total score despite individual items being potentially informative. Therefore, our objective was to examine the associations between the individual items of the MSWS-12 and mobility and whether these associations depend on disability level.

METHODS

Participants completed the MSWS-12, Two-Minute Walk Test (2MWT), Timed 25-Foot Walk (T25FW), Timed Up and Go Test (TUG) and the Four Square Step Test (FSST). Subsequently, they were divided into two groups according to their disability level, classified as either "mildly" or "moderately-severely" disabled. The correlation between individual items of the MSWS-12 and clinical measures of mobility were separately examined by Spearman's correlation coefficients; linear regression analyses were performed for each disability group, with/without adjusting for cognition, age and gender.

RESULTS

242 people with MS (PwMS), 108 mildly and 134 moderately-severely disabled, were included. Stronger correlations between the MSWS-12 items and mobility tests were found in the mildly disabled compared to the moderately-severely disabled group. The linear regression analysis showed that in the mildly disabled, item 9 (use of support outdoors) explained 35.4%, 30.8%, and 23.7% of the variance related to the 2MWT, T25FW and TUG, respectively. As for the moderately-severely disabled, the linear regression analysis presented a model which included item 8 (use of support indoors), explaining 31.6%, 18.0%, 20.2% and 9.5% of the variance related to the 2MWT, T25FWT, TUG and FSST, respectively.

CONCLUSIONS

Items 8 and 9 of the MSWS-12 focusing on the patient's use of walking support in and outdoors, provide a robust indicator of mobility capabilities for mildly and moderately-severely disabled PwMS.

The reliability and validity of the Timed Up and Go as a clinical tool in individuals with and without disabilities across a lifespan: a systematic review

PURPOSE

To summarize the available literature related to reliability and validity of the Timed Up and Go in typical adults and children, and individuals diagnosed with the following pathologies: Huntington's disease, stroke, multiple sclerosis, Parkinson's disease, spinal cord injury, Down syndrome, or cerebral palsy.

MATERIALS AND METHODS

A search was conducted using MeSH terms and keywords through a variety of databases. Data regarding reliability and validity were synthesized.

RESULTS

This review included 77 articles. Results were variable depending on the studied population. The Timed Up and Go showed excellent reliability in typical adults, in individuals with cerebral palsy, in individuals with multiple sclerosis, in individuals with Huntington's disease, individuals with a stroke, and individuals with a spinal cord injury. The TUG demonstrated strong concurrent validity for individuals with stroke and spinal cord injury. Predictive validity data was limited.

CONCLUSIONS

Based on the literature assessed, the Timed Up and Go is clinically applicable and reliable across multiple populations. The Timed Up and Go has a wide variety of clinical use making it a diverse measure that should be considered when choosing an outcome an activity based outcome measure. However, there are some limitations in the validity of the utilization of the Timed Up and Go to some populations due to a lack of data and/or poor choice of comparison outcome measures when assessing validity. Additional research is needed for young to middle aged adults.IMPLICATIONS FOR REHABILITATIONOutcome measures are a vital component of clinical practice across all populations.The Timed Up and Go is a highly studied outcome measure in the geriatric population, but lacks research of its applicability to other populations.This study was able to highlight the clinical utility of the Timed Up and Go in populations that under utilize this outcome measure.

The ability of the instrumented tandem walking tests to discriminate fully ambulatory people with MS from healthy adults

BACKGROUND

People with multiple sclerosis (PwMS) experience walking and balance deficits at the initial phases of the disease, even when classified as only minimally disabled. Complex balance tasks, such as tandem walking, are probably more sensitive in detecting mild balance difficulties compared to the standard traditional tests in this population.

RESEARCH QUESTION

The aim was to investigate different types of 3-meter tandem walking tests in fully ambulatory PwMS.

METHODS

This observational case-control study included 50 participants; 25 PwMS, 17 women and 8 men, aged 35.2 (S.D = 8.6) and 25 healthy subjects, 18 women and 7 men, aged 34.3 (S.D = 6.1). The 3-meter tandem walk tests were performed during a single session. Each subject completed a sequence of 3 consecutive tests under 3 different task conditions: normal tandem walking, backward tandem walking and cognitive tandem walking. Tandem walking tests were evaluated via three small, lightweight axial wearable accelerometers (APDM, Oregon, USA).

RESULTS

The mean EDSS for the MS group was 1.6 (S.D = 0.6) indicating minimal disability. PwMS walked slower and at a slower pace, with a prolonged double support and decreased swing phase compared to healthy subjects in normal and backward conditions. In contrast, during the cognitive task, non-significant differences were found in gait measures between the PwMS and the healthy controls. Significant differences were found between task conditions for all participants. All reduced their walking speed and walked at a slower pace in both the cognitive and backward conditions compared to the normal tandem walk condition. However, non-significant scores were found for the condition X group factor.

SIGNIFICANCE

The study provides new insights into the 3-meter tandem walk test. Findings should improve evaluation and training of dynamic balance in fully ambulatory PwMS.

The ability of clinical balance measures to identify falls risk in multiple sclerosis: a systematic review and meta-analysis

Objective:

To determine the ability of clinical measures of balance to distinguish fallers from non-fallers and to determine their predictive validity in identifying those at risk of falls.

Data sources:

AMED, CINAHL, Medline, Scopus, PubMed Central and Google Scholar. First search: July 2015. Final search: October 2017.

Review methods:

Inclusion criteria were studies of adults with a definite multiple sclerosis diagnosis, a clinical balance assessment and method of falls recording. Data were extracted independently by two reviewers. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 scale and the modified Newcastle–Ottawa Quality Assessment Scale. Statistical analysis was conducted for the cross-sectional studies using Review Manager 5. The mean difference with 95% confidence interval in balance outcomes between fallers and non-fallers was used as the mode of analysis.

Results:

We included 33 studies (19 cross-sectional, 5 randomised controlled trials, 9 prospective) with a total of 3901 participants, of which 1917 (49%) were classified as fallers. The balance measures most commonly reported were the Berg Balance Scale, Timed Up and Go and Falls Efficacy Scale International. Meta-analysis demonstrated fallers perform significantly worse than non-fallers on all measures analysed except the Timed Up and Go Cognitive ( p < 0.05), but discriminative ability of the measures is commonly not reported. Of those reported, the Activities-specific Balance Confidence Scale had the highest area under the receiver operating characteristic curve value (0.92), but without reporting corresponding measures of clinical utility.

Conclusion:

Clinical measures of balance differ significantly between fallers and non-fallers but have poor predictive ability for falls risk in people with multiple sclerosis.

The validity and reliability of the four square step test in different adult populations: a systematic review

BACKGROUND

The four square step test (FSST) was first validated in healthy older adults to provide a measure of dynamic standing balance and mobility. The FSST has since been used in a variety of patient populations. The purpose of this systematic review is to determine the validity and reliability of the FSST in these different adult patient populations.

METHODS

The literature search was conducted to highlight all the studies that measured validity and reliability of the FSST. Six electronic databases were searched including AMED, CINAHL, MEDLINE, PEDro, Web of Science and Google Scholar. Grey literature was also searched for any documents relevant to the review. Two independent reviewers carried out study selection and quality assessment. The methodological quality was assessed using the QUADAS-2 tool, which is a validated tool for the quality assessment of diagnostic accuracy studies, and the COSMIN four-point checklist, which contains standards for evaluating reliability studies on the measurement properties of health instruments.

RESULTS

Fifteen studies were reviewed studying community-dwelling older adults, Parkinson's disease, Huntington's disease, multiple sclerosis, vestibular disorders, post stroke, post unilateral transtibial amputation, knee pain and hip osteoarthritis. Three of the studies were of moderate methodological quality scoring low in risk of bias and applicability for all domains in the QUADAS-2 tool. Three studies scored "fair" on the COSMIN four-point checklist for the reliability components. The concurrent validity of the FSST was measured in nine of the studies with moderate to strong correlations being found. Excellent Intraclass Correlation Coefficients were found between physiotherapists carrying out the tests (ICC = .99) with good to excellent test-retest reliability shown in nine of the studies (ICC = .73-.98).

CONCLUSIONS

The FSST may be an effective and valid tool for measuring dynamic balance and a participants' falls risk. It has been shown to have strong correlations with other measures of balance and mobility with good reliability shown in a number of populations. However, the quality of the papers reviewed was variable with key factors, such as sample size and test set up, needing to be addressed before the tool can be confidently used in these specified populations.