WATERLOO VISION AND MOBILITY STUDY - GAIT ADAPTATIONS TO ALTERED SURFACES IN INDIVIDUALS WITH AGE-RELATED MACULOPATHY

Walking is an extremely complex task that can become seriously challen ged if one of the sensory systems which provides input to the motor sy stem is compromised. The present study evaluated gait adaptations to a ltered surface characteristics and high and low ambient light conditio ns by subjects with age-related maculopathy (ARM). Twenty subjects wit h ARM and 20 control subjects walked along a 6 m path, along which the y met 1 of 3 altered surfaces (compliant, uneven, or shiny). Kinematic data and ground reaction forces information were analyzed to discern gait adaptation strategies used by the ARM group. Ten trials on each s urface were collected under both high and low ambient light levels. Th e ARM subjects were found to be generally more cautious when walking o n the altered surfaces. For example, they walked on the altered surfac es. For example, they walked more slowly, with a longer swing time. Ho wever, gait adaptations in the ARM group were not merely scaled versio ns of normal gait but were adjustments to adapt to environmental chang es. Gait was modified to avoid tripping over a surface edge, to preven t slipping at heel contact, and to balance during stance. These adapta tions enabled subjects to maintain safe mobility when walking in a cha llenging environment.