title: Validity of gait asymmetry estimation by using an accelerometer in individuals with hemiparetic stroke.
abstract: [Purpose] The purpose of this study was to evaluate the validity of estimating step time and length asymmetries, using an accelerometer against force plate measurements in individuals with hemiparetic stroke. [Subjects and Methods] Twenty-four individuals who previously had experienced a stroke were asked to walk without using a cane or manual assistance on a 16-m walkway. Step time and length were measured using force plates, which is the gold standard for assessing gait asymmetry. In addition to ground reaction forces, trunk acceleration was simultaneously measured using an accelerometer. To estimate step time asymmetry using accelerometer data, the time intervals between forward acceleration peaks for each leg were calculated. To estimate step length asymmetry using accelerometer data, the integration of the positive vertical accelerations following initial contact of each leg was calculated. Asymmetry was considered the affected side value divided by the unaffected side value. [Results] Significant correlations were found between the accelerometer and the force plates for step time and length asymmetries (rho=0.83 and rho=0.64, respectively). [Conclusion] An accelerometer might be useful for assessing step time and length asymmetries in individuals with hemiparetic stroke, although improvements are needed for estimating the accuracy of step length asymmetry.
authors.affiliation: Department of Health Sciences, Graduate School of Medicine, Shinshu University, Japan; Japan Society for The Promotion of Science, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Oyake
authors.affiliation: Japan Society for The Promotion of Science, Japan; Department of Rehabilitation Medicine, Keio University School of Medicine, Japan.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Tokyo Bay Rehabilitation Hospital, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Sugasawa
authors.affiliation: Graduate School of Sport Sciences, Waseda University, Japan.
authors.forename: Chihiro
authors.initials: C
authors.lastname: Oda
authors.affiliation: Faculty of Rehabilitation, School of Health Sciences, Fujita Health University, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Tanabe
authors.affiliation: Department of Health Sciences, Graduate School of Medicine, Shinshu University, Japan.
authors.forename: Kunitsugu
authors.initials: K
authors.lastname: Kondo
authors.affiliation: Department of Health Sciences, Graduate School of Medicine, Shinshu University, Japan; Department of Rehabilitation Medicine, Keio University School of Medicine, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Otaka
authors.affiliation: Department of Health Sciences, Graduate School of Medicine, Shinshu University, Japan.
authors.forename: Kimito
authors.initials: K
authors.lastname: Momose
keywords: Gait analysis; Rehabilitation; Trunk acceleration