Coordination Rigidity in the Gait, Posture, and Speech of Persons with Parkinson’s Disease

Abstract

Parkinson’s disease (PD) is associated with reduced coordination abilities. These can result either in random or rigid patterns of movement. The latter, described here as coordination rigidity (CR), have been studied less often. We explored whether CR was present in gait, quiet stance, and speech—tasks involving coordination among multiple joints and muscles. Kinematic and voice recordings were used to compute measures describing the dynamics of systems with multiple degrees of freedom and nonlinear interactions. After clinical evaluation, patients with moderate stage PD were compared against matched healthy participants. In the PD group, gait dynamics was associated with decreased dynamic divergence—lower instability—in the vertical axis. Postural fluctuations were associated with increased regularity in the anterior-posterior axis, and voice dynamics with increased predictability, all consistent with CR. The clinical relevance of CR was confirmed by showing that some of those features contribute to disease classification with supervised machine learning (82/81/85% accuracy/sensitivity/specificity).

Keywords:

• classification
• complexity
• gait stability
• posture

ACKNOWLEDGMENTS

We are grateful to Dr. Kiret Dhindsa, Dr. Cristian Geny, Dr. Sophie Bayard, Cindy Lebrun, and Petra Ihalainen.

DISCLOSURE STATEMENT

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors were partly supported by grant FP7-ICT-2013-10 “Health and Wellness on the Beat” awarded to BB and SDB, contract #610633. DD received support from NIH P20GM109090 during preparation of this article.