title: Fractal dynamics of body motion in patients with Parkinson's disease.
abstract: In this paper, we assess the complexity (fractal measure) of body motion during walking in patients with Parkinson's disease. The body motion of 11 patients with Parkinson's disease and 10 healthy elderly subjects was recorded using a triaxial accelerometry technique. A triaxial accelerometer was attached to the lumbar region. An assessment of the complexity of body motion was made using a maximum-likelihood-estimator-based fractal analysis method. Our data suggest that the fractal measures of the body motion of patients with Parkinson's disease are higher than those of healthy elderly subjects. These results were statistically different in the X (anteroposterior), Y (lateral) and Z (vertical) directions of body motion between patients with Parkinson's disease and the healthy elderly subjects (p < 0.01 in X and Z directions and p < 0.05 in Y direction). The complexity (fractal measure) of body motion can be useful to assess and monitor the output from the motor system during walking in clinical practice.
authors.affiliation: Department of Gerontechnology, National Institute for Longevity Sciences, Ohbu, Aichi, Japan. sekine@nils.go.jp
authors.forename: Masaki
authors.initials: M
authors.lastname: Sekine
authors.forename: Metin
authors.initials: M
authors.lastname: Akay
authors.forename: Toshiyo
authors.initials: T
authors.lastname: Tamura
authors.forename: Yuji
authors.initials: Y
authors.lastname: Higashi
authors.forename: Toshiro
authors.initials: T
authors.lastname: Fujimoto
mesh_terms: D000054:Acceleration; D000368:Aged; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D005260:Female; D017709:Fractals; D020233:Gait Disorders, Neurologic / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008954:Models, Biological; D015233:Models, Statistical; D010300:Parkinson Disease / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D010808:Physical Examination / Q000295:instrumentation / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D014159:Transducers; D016138:Walking