Associations between clinical characteristics and dual task performance in Multiple Sclerosis depend on the cognitive and motor dual tasks used.

BACKGROUND: In persons with Multiple Sclerosis (pwMS) performing a simultaneous cognitive task while walking often results in slower gait. Clinical characteristics associated with reduced dual task (DT) performance are not yet entirely clear. This multi-centre study aimed to determine the relationship between clinical and demographical characteristics with dual task (DT) walking performance in pwMS during multiple DT conditions. METHODS: Nine DT conditions were analysed, consisting of combinations of three types of cognitive ('digit span', 'subtraction', 'vigilance') and three types of walking ('walk', 'walk with cup', 'walk over obstacles') conditions. Primary outcomes were DT gait speed (m/s) and motor DT cost of gait speed (DTCmotor, %). Secondary outcomes were clinical tests of physical and cognitive functioning and patient-reported and demographical outcomes. Firstly, univariate analyses and, subsequently, multivariate analyses with backward modelling, were conducted for each type of walking DT condition separately. Cognitive DT conditions were included in the models as main and as interaction effect with the secondary outcomes. RESULTS: Analysis were performed in 81 pwMS (EDSS 3.3 ± 1.0). In the final models of DTCmotor, the significant main effects were in 'walk' DT-conditions the Symbol Digit Modalities Test (SDMT), in 'cup' conditions the SDMT and Dynamic Gait Index and in 'obstacles' conditions age. For DT gait speed, main effects were found for the 2-Minute Walking Test (2MWT) and the Multiple Sclerosis Walking Scale for all walking conditions. Additionally, interactions between cognitive DT-conditions and SDMT, age and 2MWT were found. CONCLUSION: Clinical characteristics related to DT walking performance differed according to cognitive-motor DT-condition used. Still, in general, pwMS with a better mobility demonstrated higher DT gait speed, while a faster information processing speed was related to a lower DTCmotor.

Is the walk ratio a window to the cerebellum in multiple sclerosis? A structural magnetic resonance imaging study.

BACKGROUND AND PURPOSE: Existing research studies have demonstrated a relationship between magnetic resonance imaging (MRI) neuroimaging measures and walking speed in people with multiple sclerosis (PwMS). However, to date there are no data as to the brain structures involved in gait coordination and control in PwMS. Therefore, the aim of our study was to investigate the association between walk ratio, an indicator of gait coordination, and related brain structures in PwMS. METHODS: A brain MRI was performed by a 3.0-T MR scanner in conjunction with a volumetric analysis based on three-dimensional T1-weighted images. Regions of interest were volumes of the hippocampus, amygdala, putamen, caudate, pallidum, thalamus, cerebellum and the corpus callosum regions. Walking speed and walk ratio, defined as step length divided by step rate, was measured whilst walking on an electronic walkway. RESULTS: In all, 343 PwMS (41.1 ± 13.4 years, 69.1% female, median Expanded Disability Status Scale 2.5) were included in the study. A significant association was found between the left cerebellum volume and walk ratio after controlling for age, gender, total cranial volume and disability; R2  = 0.379, P = 0.002. A similar association was found between the right cerebellum volume and walk ratio, R2  = 0.364, P = 0.002. No correlations were observed between walk ratio and the thalamus, basal ganglia, hippocampus, amygdala and the corpus callosum volumes. No association was found between walking speed and all brain measures. CONCLUSIONS: The walk ratio should be considered when evaluating and assessing PwMS presenting with ataxia. Furthermore, it is also hypothesized that a low walk ratio indicates a lower cerebellum volume in the MS population.

Neural correlates of gait variability in people with multiple sclerosis with fall history.

BACKGROUND AND PURPOSE: The aim was to investigate the association between step time variability and related brain structures in accordance with fall status in people with multiple sclerosis (PwMS). METHODS: The study included 225 PwMS. Whole-brain magnetic resonance imaging was performed with a high-resolution 3.0 T magnetic resonance scanner in addition to volumetric analysis based on 3D T1-weighted images using the FreeSurfer image analysis suite. Step time variability was measured with an electronic walkway. Participants were defined as 'fallers' (at least two falls during the previous year) and 'non-fallers'. RESULTS: In all, 105 PwMS were defined as fallers and had a greater step time variability compared to non-fallers [5.6% (SD = 3.4) vs. 3.4% (SD = 1.5); P = 0.001]. MS fallers exhibited a reduced volume in the left caudate and both cerebellum hemispheres compared to non-fallers. On using a linear regression analysis no association was found between gait variability and related brain structures in the total cohort and the non-fallers group. However, the analysis found an association between the left hippocampus and left putamen volumes with step time variability in the faller group: P = 0.031, 0.048, respectively, controlling for total cranial volume, walking speed, disability, age and gender. Nevertheless, according to the hierarchical regression model, the contribution of these brain measures to predict gait variability was relatively small compared to walking speed. CONCLUSIONS: An association between low left hippocampal, putamen volumes and step time variability was found in PwMS with a history of falls, suggesting that brain structural characteristics may be related to falls and increased gait variability in PwMS.

Is the impact of fatigue related to walking capacity and perceived ability in persons with multiple sclerosis? A multicenter study.

BACKGROUND: The relationship between fatigue impact and walking capacity and perceived ability in patients with multiple sclerosis (MS) is inconclusive in the existing literature. A better understanding might guide new treatment avenues for fatigue and/or walking capacity in patients with MS. OBJECTIVE: To investigate the relationship between the subjective impact of fatigue and objective walking capacity as well as subjective walking ability in MS patients. METHODS: A cross-sectional multicenter study design was applied. Ambulatory MS patients (n = 189, age: 47.6 ±â€¯10.5 years; gender: 115/74 women/men; Expanded Disability Status Scale (EDSS): 4.1 ±â€¯1.8 [range: 0-6.5]) were tested at 11 sites. Objective tests of walking capacity included short walking tests (Timed 25-Foot Walk (T25FW), 10-Metre Walk Test (10mWT) at usual and fastest speed and the timed up and go (TUG)), and long walking tests (2- and 6-Minute Walk Tests (MWT). Subjective walking ability was tested applying the Multiple Sclerosis Walking Scale-12 (MSWS-12). Fatigue impact was measured by the self-reported modified fatigue impact scale (MFIS) consisting of a total score (MFIStotal) and three subscales (MFISphysical, MFIScognitive and MFISpsychosocial). Uni- and multivariate regression analysis were performed to evaluate the relation between walking and fatigue impact. RESULTS: MFIStotal was negatively related with long (6MWT, r = -0.14, p = 0.05) and short composite (TUG, r = -0.22, p = 0.003) walking measures. MFISphysical showed a significant albeit weak relationship to walking speed in all walking capacity tests (r = -0.22 to -0.33, p < .0001), which persisted in the multivariate linear regression analysis. Subjective walking ability (MSWS-12) was related to MFIStotal (r = 0.49, p < 0.0001), as well as to all other subscales of MFIS (r = 0.24-0.63, p < 0.001), showing stronger relationships than objective measures of walking. CONCLUSIONS: The physical impact of fatigue is weakly related to objective walking capacity, while general, physical, cognitive and psychosocial fatigue impact are weakly to moderately related to subjective walking ability, when analysed in a large heterogeneous sample of MS patients.

Concern about falling is associated with step length in persons with multiple sclerosis.

BACKGROUND: Fear of falling is one of the major concerns of people with multiple sclerosis (MS). Although, it is likely that associations between spatio-temporal gait parameters and fear of falling exist in the MS population, these relationships have never been extensively studied. AIM: Aim of the study was to determine if fear of falling is associated with spatio-temporal gait parameters in persons with MS. DESIGN: Cross sectional study with a control group. SETTINGS: Multiple Sclerosis Center, Sheba Medical Center, Tel-Hashomer, Israel. METHODS: One-hundred and thirty relapsing-remitting patients diagnosed with MS, 79 women and 51 men aged 42.6 (SD=11.9), participated in this investigation. Twenty-five healthy subjects, 14 women and 11 men aged 38.5 (SD= 12.3), served as controls. Spatio-temporal parameters of gait were studied using the GAITRiteTM system (CIR Systems Inc., NJ, USA); Falls Efficacy Scale International (FES-I) was used to assess the level of concern relating to falls. Participants who scored >20 were classified as more concerned (N.=83), while those scoring ≤20 were defined as less concerned (N.=47). RESULTS: More concerned participants walked slower, took smaller steps, prolonged double support phase, wider base of support and a shorter single support phase compared to the less concerned group. According to step one of the multiple linear regression model, the spatial gait component accounted for 30.9% of the variance related to fear of falls (F=56.3, P<0.001). Step two added the gait temporal component, thus increasing the variance to 36.7% (F=36.2, P<0.001). Step three added the gait asymmetry parameters, thus increasing the predictor model to account for 40.3% of the variance in fear of falling (F=29.6, P<0.001). CONCLUSION: The present study provides quantitative evidence establishing spatio-temporal gait performance in individuals with MS relative to the level of fear of falling. CLINICAL REHABILITATION IMPACT: Spatio-temporal gait parameters may aid in assessing the level of fear of falling in people with MS. Step length may also serve as a surrogate outcome for assessing outcomes of interventions aimed at reducing fear of falling in the MS population.

A systematic review of the effectiveness of Kinesio Taping--fact or fashion?

In this systematic review article, we assessed the effects of therapeutic Kinesio Taping (KT) on pain and disability in participants suffering from musculoskeletal, neurological and lymphatic pathologies. Four online databases (CINAHL, Cochrane Library, MEDLINE, PEDro) were comprehensively searched from their inception through March 2012. The initial literature search found 91 controlled trials. Following elimination procedures, 26 studies were fully screened. Subsequently, 12 met our inclusion criteria. The final 12 articles were subdivided according to the basic pathological disorders of the participants' musculoskeletal (N.=9), neurological (N.=1) and lymphatic (N.=2) systems. As to the effect on musculoskeletal disorders, moderate evidence was found supporting an immediate reduction in pain while wearing the KT. In 3 out of 6 studies, reduction of pain was superior to that of the comparison group. However, there is no support indicating any long-term effect. Additionally, no evidence was found connecting the KT application to elevated muscle strength or long-term improved range of movement. No evidence to support the effectiveness of KT for neurological conditions. As to lymphatic disorders, inconclusive evidence was reported. Although KT has been shown to be effective in aiding short-term pain, there is no firm evidence-based conclusion of the effectiveness of this application on the majority of movement disorders within a wide range of pathologic disabilities. More research is clearly needed.

Effect of a cognitive task on postural control in patients with a clinically isolated syndrome suggestive of multiple sclerosis.

BACKGROUND: Patients with multiple sclerosis (MS) frequently experience poor postural control affecting mobility and/or cognitive impairment, even in the early stages of the disease. As postural control consumes attentional resources, it is essential to test stability during a cognitive task. AIM: To assess postural control and determine the effect of a cognitive task on balance in patients with a clinically isolated syndrome (CIS) suggestive of MS, within 3 months from onset. DESIGN: Observational case control study SETTING: Multiple Sclerosis Center and Institute of Motor Functions, Sheba Medical Center, Tel Hashomer, Israel POPULATION: Fifty-two CIS patients, aged 35.2±1.3 years, disease duration of 54±6.2 days and Expanded Disability Status Scale (EDSS) of 1.7±0.2, participated in the study. The control group consisted of 28 age and gender matched healthy subjects. METHODS: Stability was evaluated by the quantifying movement of the center of pressure (CoP) during standing under three conditions: eyes open, eyes closed, and while performing the modified Stroop test. Sway rate and CoP data was collected by a computerized force platform device. RESULTS: After combining major postural control parameters, only 50% of the patients performed normally. Differences in postural variables were found between patients and healthy subjects (P<0.01). Both sway rate and standard deviation of the CoP in all test conditions were significantly higher in patients compared to controls. The cognitive task resulted in an elevated sway rate both in CIS patients and the control group when compared with the eyes open task. Within 3 months of the onset of neurological symptomatology, postural instability was detected in 50% of CIS patients using a dedicated balance measurement device. CONCLUSION: As these findings are associated with the very early phase of MS, it appears that the ongoing pathological disease process is already taking place with regard to the balance control system. CLINICAL REHABILITATION IMPACT: Identification of postural abnormalities in the early stages is important in order to establish proper intervention programs.