Comparison of Slip Training in VR Environment And on Moveable Platform.

Slip training is gaining popularity as an innovative fall intervention approach. The objective of this study was to compare the efficacy of two different slip training modality (moveable platform and virtual reality) in reducing fall frequency and improving reactive recovery in older adults. Thirty-six healthy older adults were involved in a laboratory study, and were equally and randomly divided into the control group, the moveable platform training (MPT) group, and the virtual reality training (VRT) group. The MPT was achieved by inducing slips using a custom built sliding device consisting of a low friction, motorized moveable platform. The VRT was conducted by inducing visual perturbation in a head mounted display while subjects walked on a treadmill. All groups performed slip trials (kinematics, kinetics and EMG data were collected) on an actual slippery floor surface before and after a training session. The results indicated a significant reduction in fall frequency in both training groups. Between MPT and VRT groups, significant differences were also found in forward trunk rotations, peak knee angular velocity, ankle coactivity, and muscular activity in tibialis anterior. It was concluded that slip training in VR environment could produce comparable results in fall intervention.

Use of item response analysis to investigate measurement properties and clinical validity of data for the dynamic gait index.

BACKGROUND AND PURPOSE: The Dynamic Gait Index (DGI) is a standardized clinical assessment that aids in evaluating a subject's ability to modify gait in response to changing demands. The purpose of this study was to use Rasch measurement theory to examine whether the DGI rating scale meets suggested psychometric guidelines, whether the hierarchical order of DGI tasks is consistent with a clinically logical testing procedure, and whether the DGI represents a unidimensional construct. SUBJECTS: Subjects were 84 community-dwelling male veterans (age range=64-88 years; mean+/-SD=75+/-6.47 years). METHODS: Data were retrieved retrospectively from the participants' clinical records. The Rasch measurement model with the WINSTEPS program was used in this study because it offers distinct advantages over traditional psychometric approaches. RESULTS: Overall, the DGI showed sound item psychometric properties. Each of the original 4 rating scale categories appeared to distinctly identify subjects at different ability levels. The analysis revealed a clear item difficulty hierarchical order that is generally consistent with clinical expectations. In addition, fit statistics and principal components analysis indicated that the 8 items of the DGI appear to represent a single construct. DISCUSSION AND CONCLUSION: The results suggest that the rating scale of the DGI is used appropriately for community-dwelling older subjects with balance problems. The findings support the continued use of this well-constructed scale for clinical and research assessment in a community-dwelling population of older subjects.

Feasibility of electromyography-triggered neuromuscular stimulation as an adjunct to constraint-induced movement therapy.

BACKGROUND AND PURPOSE: The purpose of this case report is to explore the feasibility of electromyography-triggered neuromuscular stimulation (EMG-stim) as an adjunct to constraint-induced movement therapy (CIMT). CASE DESCRIPTION: The patient was a 72-year-old man, 10 years poststroke, who did not meet traditional CIMT criteria. The EMG-stim was applied to the wrist extensors of the patient's weaker arm for one half of the CIMT training hours. OUTCOMES: The intervention was feasible for this individual. Improvements were observed in motor behavior, quality and amount of use, muscle activity, wrist range of motion, and reaction time of the more-affected extremity. These improvements were paralleled by a change in the size and location of the extensor digitorum communis muscle representation in the primary motor cortex, as measured by transcranial magnetic stimulation mapping. DISCUSSION: These changes suggest that using EMG-stim as an adjunct to CIMT should be further investigated in individuals who have low functional abilities following stroke.

Rating scale analysis of the Berg Balance Scale.

OBJECTIVES: To examine, using Rasch analysis, the rating scale performance of the Berg Balance Scale (BBS) and to describe the 45/56 cutoff score in functional terms. DESIGN: Retrospective chart review of BBS scores. Rasch rating scale analysis was performed on these data. SETTING: Outpatient Veterans Affairs medical center. PARTICIPANTS: One hundred (99 men, 1 woman) community-dwelling veterans referred for balance deficits (age range, 64-88y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: The BBS. RESULTS: Condensing item-rating categories allowed the elimination of underutilized categories and constructed categories that better separated people of differing abilities. Rating pivot points were developed for each item to represent a transition between passing and failing. Following pivot-point development and rating scale rescoring, person and item measures became more evenly distributed across the BBS and resulted in changes in item difficulty order. In our sample, functional indicators of a score of at least 45/56 were a rating of passing the item "tandem stance," as well as passing 2 of the following 3 items: "alternating foot," "standing on one leg," and "look behind." CONCLUSIONS: Our findings provide direction for improving the rating scale structure for each of the items and establish a connection between the BBS cutoff score of 45/56 and functional ability.