Temporal and spatial characteristics of gait during performance of the dynamic gait index in people with and people without balance or vestibular disorders

Background and Purpose. Understanding underlying gait characteristics during performance of the Dynamic Gait Index (DGI) could potentially guide interventions. The purpose of this study was to describe the characteristics and reliability of gait performance during the level walking items of the DGI in people with balance or vestibular dysfunction. The study was a cross-sectional investigation with 2-group comparisons. Subjects and Methods. Forty-seven subjects (mean age = 59.2 years, SD=8.5, range = 24-90) participated in the study; 26 were control subjects, and 21 were subjects with balance or vestibular dysfunction. Three trials of each level gait item were administered to subjects as they ambulated on an instrumented walkway. Test-retest reliability was determined by use of an intraclass correlation coefficient (3,1) 2-way random-effects model for gait parameters associated with continuous walking and the item requiring turning and stopping quickly. Mean gait parameter differences between control subjects and subjects with balance or vestibular disorders were compared by use of a multivariate analysis of variance for each gait task. Results. The reliability of most gait parameters during DGI performance were fair to excellent between trials. Subjects with balance or vestibular disorders demonstrated differences in gait characteristics compared with control subjects. The heterogeneity of the group of subjects with balance or vestibular disorders does not permit inferences to be drawn regarding the relationship between gait and any specific balance or vestibular diagnosis. The results are most pertinent to people with chronic balance or vestibular disorders. Discussion and Conclusion. Gait parameters underlying dynamic walking appeared to be relatively reliable across multiple trials and distinguished subjects with balance or vestibular disorders. Evaluating a person's performance on items of the DGI may be useful in identifying gait deviations and in evaluating gait improvements as a result of interventions.