2017 Volume 4 Issue 1 Pages 33-42
【Objective】This study was conducted to analyze the effect of fall experience on whole waveform of toe-height trajectory during swing phase of barefoot walking. We also focused on the effect of participant’s sex.
【Methods】Participants were 88 elderlies (56 non-fallers and 32 fallers) aged 60 to 77. The principal component analysis (PCA) was conducted using a 166 x 202 input matrix constructed from the participants’ time-normalized average and standard deviation of the toe-heights during swing phase (101 data × 2 parameters). Two-way (age x sex) multivariate analysis of variance were conducted on the principal component scores (PCSs) of principal component vectors (PCVs) 1 through 11.
【Results】We identified a PCV that exhibits a significant fall experience effect (PCV 3, F (1, 165) ＝ 5.936, p ＜ 0.05, ES ＝ 0.031) and significant fall experience / sex interaction (PCV 7, F (1, 165) ＝ 7.573, p ＜ 0.01, ES ＝ 0.044). These findings suggest that the toe-height trajectory related to PCV 3 and PCV 7 is the important characteristic that affects the risk of falling while walking. We therefore recombined the toe-height trajectory corresponding to PCV 3 and PCV 7, and found that the local minima of toe height during swing-phase for fallers tend to appear earlier than non-fallers. Further, the variability of the toe height trajectory during late-swing phase for fallers was larger than that for non-fallers regardless of sex.
【Conclusions】These results indicate that we should focus whole toe-trajectory as well as minimum toe clearance to understand the gait characteristics of fallers.
