title: Analysis of antagonistic co-contractions with motorized passive movement device in patients with Parkinson's disease.
abstract: Patients with Parkinson's disease (PD) suffer from an increased resistance to passive movement of a joint, called as rigidity. Stretch reflex and shortening reaction were suggested to be associated to the rigidity, however, the mechanism is still poorly understood. We hypothesized that the co-contraction of antagonistic muscle pairs is enhanced in patients with PD and this induces resistance persisting throughout its range of motion. To test the hypothesis, we developed a motorized device for application of passive movement of the wrist joint and investigated the co-contraction of muscles during passive movement. It consisted of a servo motor connected to a rotating axis with a timing belt, load cell for the measurement of resistance, and other elements for the fixation of arm and hand. Repetitive passive movement was applied to the wrist joint of patients. Co-contraction of antagonistic muscle pairs was significantly greater in patients than in normal subjects (p<0.001), suggesting that the enhanced co-contraction is associated with the mechanical resistance during passive movement, i.e. rigidity. Co-contraction during extended state was greater than the other states (p<0.001), which implies that the length-feedback mechanism may play the important role in co-contraction.
authors.affiliation: Biomedical Engineering, Konkuk University, Choongju 380-701, Korea.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kwon
authors.affiliation: Biomedical Engineering, Konkuk University, Choongju 380-701, Korea.
authors.forename: Ji-Won
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Biomedical Engineering, Konkuk University, Choongju 380-701, Korea.
authors.forename: Yeji
authors.initials: Y
authors.lastname: Ho
authors.affiliation: Biomedical Engineering, Konkuk University, Choongju 380-701, Korea.
authors.forename: Hyeong-Min
authors.initials: HM
authors.lastname: Jeon
authors.affiliation: Biomedical Engineering, Konkuk University, Choongju 380-701, Korea.
authors.forename: Min-Jung
authors.initials: MJ
authors.lastname: Bang
authors.affiliation: Biomedical Engineering, Konkuk University, Choongju 380-701, Korea BK21Plus Research Institute of Biomedical Engineering, Konkuk University, Choongju 380-701, Korea.
authors.forename: Gwang-Moon
authors.initials: GM
authors.lastname: Eom
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Korea.
authors.forename: Seong-Beom
authors.initials: SB
authors.lastname: Koh
mesh_terms: D000368:Aged; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D015915:Motion Therapy, Continuous Passive / Q000295:instrumentation*; D009119:Muscle Contraction; D009127:Muscle Rigidity / Q000209:etiology / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology*; D004856:Postural Balance; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D012371:Robotics / Q000295:instrumentation*; D012680:Sensitivity and Specificity; D014955:Wrist Joint / Q000503:physiopathology
keywords: Parkinson's disease; co-contraction; motorized device; passive movement; rigidity