Evaluation of Balance Control in Patients with Idiopathic Parkinson's Disease Using Tetra-ataxiometric Posturography

Objective: To investigate the postural stability of patients with mild to moderate stage of idiopathic parkinson's disease (IPD) using Tetra-ataxiometric posturography (Tetrax) and to evaluate the correlation between balance and activity of daily living (ADL). Method: Twenty patients with IPD at mild to moderate stage, twenty young controls and twenty elderly controls were enrolled in this study. In order to evaluate postural stability, we checked stability index, fourier index, weight distribution index, synchronization index, and fall index at eight positions using Tetrax. We also assessed Berg Balance Scale, Postural Instability and Gait Difficulty (PIGD) score of Unified Parkinson Disease Rating Scale (UPDRS). In order to evaluate the correlation between balance and functional performance, the ADL score of UPDRS was checked in the patients with IPD. Results: The patients with IPD showed a significantly higher fall index, weight distribution indices in five positions than the elderly controls. The stability indices of the patients with IPD were higher in all positions, but significantly higher in only one position than the elderly controls. The fallers in the IPD patients had a higher fall index and lower synchronization indices than the non-fallers. The balance and functional performance showed significant correlations in the IPD patients. Conclusion: We could identify a high falling risk and uneven weight distribution in the IPD patients and a close correlation between balance and functional performance. Therefore the evaluation of postural stability should be considered from mild stage because postural instability might impair activity of daily living and increase fall risk.