Gait analysis in a component timed-up-and-go test using a smartphone application.

BACKGROUND: The timed-up-and-go test (TUG) is a popular test for mobility, but it only measures the total time to complete tasks. Recent advances in smartphone technology enables measuring respective times of 6 components in the test (Stand, Go, Turn1, Come, Turns and Sit). We examined availability of these data for assessing different gait patterns.

METHODS: This study enrolled 32 patients with probable idiopathic normal-pressure hydrocephalus and 87 age-matched active participants as controls. All the patients responded positively to cerebrospinal fluid (CSF) removal, among whom 19 underwent surgery with positive outcomes. The TUG was performed using a free smartphone application. The components were automatically detected, and their respective times were computed. Statistical analyses included item cluster analysis.

RESULTS: In the control group, high correlations (r ≥ 0.7) were observed in two pairs of Go and Come, and Turn1 and Turn2, which reflect straight walk and turn. This pattern was lost in the baseline and after CSF removal in the hydrocephalus group. After surgery, the two pairs in the control group regained high correlations. The item cluster analysis showed the pattern changes more clearly.

CONCLUSIONS: A smartphone is useful for analyzing gait patterns in the TUG, which can be applicable for various gait disorders.