title: Effects of postural threat on walking features of Parkinson's disease patients.
abstract: This study investigated whether or not gait kinematics among healthy older individuals and Parkinson's disease (PD) patients are influenced by postural threat. Eight healthy older individuals and eight PD patients were examined while walking at self-selected velocities, under three conditions of postural threat: unconstrained floor; constrained floor (19cm wide); constrained and elevated floor (19cm wide by 10cm high). Independent of the surface conditions, due to motor disturbances caused by the PD these patients walked slower, with shorter strides, and spent more time in the double support phase and less time in the swing phase than did their matched controls. Increases in postural threat resulted in altered gait kinematics for all subjects. Specifically, stride length, stride velocity, cadence, and heel contact velocity decreased, and stride duration and double support duration increased relative to increases in postural threat. All gait alterations were the result of participants' attempts to facilitate locomotion control and maintain stability. The results of this study reveal that width and height constraints effectively perturbed the balance of all of the walking older individuals. The PD patients were able to modulate gait parameters when faced by a postural threat task.
authors.affiliation: UNESP -- São Paulo State University at Rio Claro, Posture and Gait Studies Lab, Brazil.
authors.forename: Maria Joana Duarte
authors.initials: MJ
authors.lastname: Caetano
authors.forename: Lilian Teresa Bucken
authors.initials: LT
authors.lastname: Gobbi
authors.forename: Mónica Del Rosario
authors.initials: Mdel R
authors.lastname: Sánchez-Arias
authors.forename: Florindo
authors.initials: F
authors.lastname: Stella
authors.forename: Sebastião
authors.initials: S
authors.lastname: Gobbi
mesh_terms: D000368:Aged; D005080:Exercise Test / Q000379:methods*; D005260:Female; D005684:Gait / Q000502:physiology; D020233:Gait Disorders, Neurologic / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D007866:Leg / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000503:physiopathology; D010300:Parkinson Disease / Q000175:diagnosis / Q000503:physiopathology*; D004856:Postural Balance / Q000502:physiology*; D011237:Predictive Value of Tests; D016138:Walking / Q000502:physiology