Session Information
Date: Tuesday, June 21, 2016
Session Title: Parkinson's disease: Pathophysiology
Session Time: 12:30pm-2:00pm
Location: Exhibit Hall located in Hall B, Level 2
Objective: To determine the effect of floor square size on turning behavior in patients with PD.
Background: Turning has been repeatedly shown to be the most relevant trigger situation for festination and freezing gait (FOG). As a reduction in step size was shown to elicit FOG episodes, we hypothesized that a reduction of the side length of the floor square wherein patients turn will co-determine the stepping count in patients with PD, particularly in those with FOG.
Methods: We conducted a cross-sectional study with N=36 patients with PD and N=18 healthy controls. We assessed the MDS-UPDRS score for cognition, non-motor and motor symptoms, the FOG-questionnaire and the FOG score. Patients performed 360° turns of floor square sizes with side lengths of 50, 40, 30 cm. Their stepping behavior, i.e. step count, turn duration and variability was evaluated by using objective inertial measurements obtained from accelerometers attached to shank and thighs. Clinical data are descriptively analyzed. Results from mixed-model ANOVA are given as means and corrected post-hoc by Tukey’s range test.
Results: Patients / healthy controls were mean 65.4 /62.6 years old. PD patients had a disease duration of 9.4 years. Subjective (FOG-Q) and objective (FOG-S) freezing assessments were highly intercorrelated (r=.71, p.0001). Healthy controls, PD w/o and PD w/ FOG took mean 10.1, 13.6, and 29.2 steps to turn, respectively. In 30 cm, 40 cm and 50 cm floor squares 23.6, 16.2, and 13.1 steps were needed. Patients with PD took more steps compared to HC (p<0.0001), and this was attributed to the presence of FOG (p<0.0001). Floor square size strongly affected the number of steps (p<0.001).
Conclusions: We recorded conclusive data from a small cross-sectional cohort demonstrating an important contribution of the side length of the floor squares on the step count. This observation could help explain why turning is the most relevant trigger situation for festination and FOG. Floor markers should be standardized for objective assessments of freezing during turns.
Part of the data has been presented in different form as a poster at the IAPRD in Milano, December 2015.
To cite this abstract in AMA style:
U.M. Fietzek, L. Stuhlinger, A. Plate, A.O. Ceballos-Baumann, K. Bötzel. Floor square size predicts step count of 360° turns in PD patients with freezing [abstract]. Mov Disord. 2016; 31 (suppl 2). https://www.mdsabstracts.org/abstract/floor-square-size-predicts-step-count-of-360-turns-in-pd-patients-with-freezing/. Accessed May 16, 2025.« Back to 2016 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/floor-square-size-predicts-step-count-of-360-turns-in-pd-patients-with-freezing/