Parkinson's Disease (PD) subjects are less able to adapt gait to fluctuating motor demands in daily life
situations than the healthy elderly, e.g. in crowded places, crossing the road, and starting or stopping at traffic lights.
Several studies proved gait abnormalities in PD. However, to our knowledge there is currently no biomechanical test that
deals with the ability in gait adaptation. The aim of this study was to develop and evaluate a new biomechanical test
which proves the adaptability of gait to fluctuating external conditions.
In order to have a reproducible, quantitative gait-test, a treadmill was used, accessed by a special software. The so called
adaptability-of-gait test (AOG) changed the treadmill's velocity ballistically and unpredictably for the test subjects. 49
PD-subjects and 10 age-matched controls (HC) participated in the study. In order to subdivide PD subjects in
homogeneous groups, we used a cluster analysis. In a first-step of evaluation we focused on differences between PD with
moderate (PDM) and severe disease stages (PDS) and HC and examined correlations according to existing, valid tests,
e.g. Unified Parkinson Disease Rating Scale (UPDRS) subscales, clinical and biomechanical gait-assessments.
Results showed significant differences in gait-adaptation between the groups. Severe PD had a worse gait adaptation
compared to PD moderate and HC. Correlation analysis of the PD sample showed significance differences between the
AOG-test and bradykinesia and facial expression, but no significances differences according to conventional clinical gait
assessments, e.g. Webster gait-test. We conclude that the AOG-test has potentials to identify a new gait performance: the
adaptation of gait.