COMPARISON OF STATIC POSTURAL BALANCE IN PATIENTS WITH SWEDDS AND PARKINSON’S DISEASE

Differentiating scans without evidence of dopaminergic deficits (SWEDDs) from Parkinson’s disease (PD) is very important to avoid costly and inappropriate interventions. The postural balance strategy patients with SWEDDs are not clear. This study investigates the difference in static postural balance between patients with SWEDDs and PD. Twenty-two patients (11 SWEDDs and 11 PD groups) and 11 control groups were instructed to quietly stand on a custom-made force platform. The outcome measures were, mean distance, 95% confidence ellipse area, mean velocity, mean frequency, peak frequency and peak power derived from the center of pressure (COP) data in overall, medio-lateral (ML) and anterio-posterior (AP) directions. As statistical analysis, ANOVA and post hoc tests were conducted for comparison of patients with SWEDDs and PD. SWEDDs patients presented a smaller postural sway size and a more frequent postural sway mainly in the ML direction ( p < 0 . 0 5 ). On the contrary, there were no significant differences in mean velocity and peak power. Also, no significant differences existed between SWEDDs and normal subjects ( p > 0 . 0 5 ). The results reflect that a few COP-based outcome variables might be useful to distinguish SWEDDs patients from PD patients. This study suggests that a static postural balance test can be used for clinical screening and identification of potential SWEDDs.