Article

Quantitative measures detect sensory and motor impairments in multiple sclerosis

Department of Neurology, Johns Hopkins University, Baltimore, MD, USA.
Journal of the neurological sciences (Impact Factor: 2.26). 03/2011; 305(1-2):103-11. DOI: 10.1016/j.jns.2011.03.003
Source: PubMed

ABSTRACT Sensory and motor dysfunction in multiple sclerosis (MS) is often assessed with rating scales which rely heavily on clinical judgment. Quantitative devices may be more precise than rating scales.
To quantify lower extremity sensorimotor measures in individuals with MS, evaluate the extent to which they can detect functional systems impairments, and determine their relationship to global disability measures.
We tested 145 MS subjects and 58 controls. Vibration thresholds were quantified using a Vibratron-II device. Strength was quantified by a hand-held dynamometer. We also recorded Expanded Disability Status Scale (EDSS) and Timed 25-Foot Walk (T25FW). t-tests and Wilcoxon-rank sum were used to compare group data. Spearman correlations were used to assess relationships between each measure. We also used a step-wise linear regression model to determine how much the quantitative measures explain the variance in the respective functional systems scores (FSS).
EDSS scores ranged from 0-7.5, mean disease duration was 10.4 ± 9.6 years, and 66% were female. In relapsing-remitting MS, but not progressive MS, poorer vibration sensation correlated with a worse EDSS score, whereas progressive groups' ankle/hip strength changed significantly with EDSS progression. Interestingly, not only did sensorimotor measures significantly correlate with global disability measures (i.e., EDSS), but they had improved sensitivity, as they detected impairments in up to 32% of MS subjects with normal sensory and pyramidal FSS.
Sensory and motor deficits in MS can be quantified using clinically accessible tools and distinguish differences among MS subtypes. We show that quantitative sensorimotor measures are more sensitive than FSS from the EDSS. These tools have the potential to be used as clinical outcome measures in practice and for future MS clinical trials of neurorehabilitative and neuroreparative interventions.

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Available from: Kathleen M Zackowski, Nov 10, 2014
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    • "This study builds on to the literature on foot vibration thresholds in PwMS [7] [8] by testing vibration at additional sites and further investigating the relationship with clinical measures of balance (the Berg balance scale (BBS)) and, both short (the Timed Up and Go test (TUG)) and long (the 6 min walking test (6MWT)) walking tests. "
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    ABSTRACT: The aim of this study was to investigate the relationship between foot vibration threshold and walking and balance functions in people with Multiple Sclerosis (PwMS). The study sample consisted of 34 participants with mean age of 49.5 years (SD 11.13). Participants were able to walk independently or with an assistive device. Participants underwent vibration threshold testing using the Neurothesiometer (NT), followed by the 6 minute walking test (6MWT), the Timed up and go test (TUG) and the Berg balance scale (BBS). We found a statistically significant relationship between foot vibration threshold and all outcome measures used. The first metatarsophalangeal joint had the strongest correlation with BBS (-0.585, p < 0.01), 6MWT (-0.557, p < 0.01) and TUG (0.498, p < 0.01). We also found that vibration threshold scores differed between those people with MS with and without walking limitations (Mann-Whitney U test, p < 0.01 for all testing points). In conclusion, these findings confirm the relationship between foot vibration threshold and clinical measures of walking and balance in PwMS and add to literature predictive validity of foot vibration threshold. They also suggest that vibration threshold may be important to consider when identifying people in need of intervention or when evaluating the effect of rehabilitation and exercise interventions.
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