THE COMBINED INFLUENCES OF VISUAL INFORMATION, SPATIAL WORKING MEMORY AND PROPRIOCEPTIVE FEEDBACK ON POSTURAL STABILITY OF INDIVIDUALS WITH PARKINSON’S DISEASE : A DOUBLE-BLIND RANDOMIZED CONTROLLED TRIAL

Background and Objectives: Disturbance in the processing of proprioception contributes to characteristic Parkinson’s disease (PD) postural instability which can be cited as a fourth core feature of PD in addition to the early emerging gait abnormalities. This study is aimed at measuring the combined influences of visual information, spatial working memory, and proprioceptive feedback on the diminished postural control in PD. Design: A double-blind randomized controlled trial. Participants and settings: Twenty six patients with PD participated in this study. They were randomly assigned to either group one (G1) who received proprioceptive training with task related visual biofeedforward/back using a force platform in addition to a traditional physical therapy program or group two (G2) who received only the traditional physiotherapy program. Outcome measures: Rhythmic weight shift, sit to stand and tandem gait examination protocols of the computerized dynamic posturography were used to measure the sensorimotor performance. Results: Significant improvements were observed (P < 0.05) in on-axis velocity, directional control, weight transfer, rising index, center of gravity sway, step width, speed, end sway. In G2 a significant improvement is only observed with sit to stand test. Conclusion: Long term training based on integrated proprioceptive and spatial visual information has a positive effect on the sensorimotor performance and postural instability caused by the PD. The results also support that motor relearning abilities is retained in subjects with PD.