Effect of Secondary Motor Task on Performance of Stair Descent in People with Idiopathic Parkinson’s Disease

In people with Parkinson’s disease (PD), dual tasking is difficult because of the impaired motor functions of the basal ganglia. It causes postural instability, reduction in gait speed, decreased stride length, increased festination and freezing. So it can also influence performance on stair ambulation. This creates a need to study the effect of dual tasks on stair ambulation, especially stair descent. 30 subjects were selected from various hospitals in Delhi. After taking the informed consent, the subjects were made to descend down the stairs under two conditions: stairs descent only and stairs descent with secondary motor task. The time taken in both the activities was recorded along with the scores on Observational Stair Parameter Scoring System (OSPS). Time taken by the subjects and the scores on OSPS for performing secondary task was more than the normal stair descent. The performance of stair descent with secondary task became more difficult than descent without the secondary task.