Abstracts Category : Other

Gait adaptability and fall risk: effects of age, Parkinsons disease and step training

by Caetano Maria Duarte

The ability to adjust gait is crucial when performing daily living activities such as avoiding obstacles and crossing a busy street. In older age and in conditions such as Parkinsons disease, poor gait adaptability might contribute to tripping; a frequently reported cause of falls in these groups. In this PhD project I devised a new overground walking task to assess peoples ability to respond to obstacles and targets appearing at short notice on a walkway, i.e. a test of gait adaptability that reflects the cognitive and motor challenges required for walking in many daily life situations. Five studies were conducted. The first study compared gait adaptability performance in younger and older people. The second examined the contributions of cognitive and sensorimotor functions to gait adaptability. The third investigated associations between gait adaptability and fall risk and the extent to which gait adaptability is affected by the addition of a concurrent cognitive task. The fourth compared adaptive stepping and gait in people with Parkinsons disease and healthy controls and the fifth investigated the effectiveness of a step training program to improve gait adaptability in people with Parkinsons disease. The main findings were that gait adaptability is: (i) impaired in older adults (e.g. high prevalence of errors, reduced gait speed, shorter steps, longer time in double-support and increased number of steps taken to approach the targets and obstacles); (ii) associated with impaired executive function, slow reaction time, increased postural sway, weaker quadriceps strength and higher concern about falling; (iii) associated with high risk of falls while mediated by reduced executive function, increased concern about falling and weaker quadriceps strength; (iv) impaired in people with Parkinsons disease (increased number of steps taken to approach the obstacle and poorer target stepping accuracy); and lastly (v) a minimally supervised home-based videogame stepping training was not effective in improving gait adaptability performance in people with Parkinsons disease. The findings of this PhD research elucidate several aspects of fall risk in older people and people with Parkinsons disease. They may facilitate both the development of fall risk assessments and fall prevention strategies for these high risk groups.Advisors/Committee Members: Lord, Stephen, Neuroscience Research Australia, Faculty of Medicine, UNSW, Menant, Jasmine, Neuroscience Research Australia, Faculty of Medicine, UNSW.