Gait & Posture Special Issue: Gait adaptations in response to obstacle type in fallers with Parkinson's disease

Gait impairment places older adults and people with Parkinson's disease (PD) at an increased risk of falls when walking over obstacles. Increasing the height of obstacles results in greater challenge to balance however little is known about the demands encountered when negotiating obstacles of greater depth which may be greater for PD who often walk with a short, shuffling gait.

To describe gait adaptation in older adults and people with PD when walking over long and tall obstacles.

20 people with PD and 13 older adults with a history of falls walked across an instrumented walkway under four conditions: level walking, and over a small, long and tall obstacle. Differences due to group, step and obstacle type were evaluated using General Linear Models.

An increased step duration, longer single limb support and a wider step (p < .033) were observed when crossing the tall obstacle for both older adults and PD. The PD group completed the crossing steps more slowly than controls, with a shorter step and longer single limb support (p < .043). Obstacle type did not significantly influence step length.

The greatest temporal-spatial adaptations were elicited when participants negotiated the tall obstacle. Electing a wider step when crossing the tall obstacle was a strategy common to both faller groups (older adults and PD). The tall obstacle presented added challenge for PD who spent longer in single limb support during the crossing steps compared to controls. The long obstacle did not cause a disproportionate change in step length in people with PD, and we suggest that the obstacle may have acted as a visual cue in this group.