title: Vertical ground reaction force shape is associated with gait parameters, timed up and go, and functional reach in elderly females.
abstract: OBJECTIVE
  The aim of this study was to evaluate the relationship between knee pain and various indicators of the combined performance of the lower extremity (including gait parameters, functional performance such as timed up and go, and functional reach test) and to determine whether the classification of vertical ground reaction forces correlates with gait parameters and functional performance.
  
  
  METHODS
  Simultaneous analysis of gait, time-distance parameters and vertical ground reaction force. Timed up and go, and functional reach test were examined in 130 elderly women. The vertical component of the ground reaction force was grouped into 2 categories: M-shaped and non-M-shaped.
  
  
  RESULTS
  No significant association was found between knee pain and timed up and go, functional reach test, or gait parameters in elderly female participants. There were significant differences between subjects with M- and non-M-shaped vertical ground reaction forces with regard to timed up and go, functional reach test and Japan Orthopaedic Association score. There were also significant differences between the 2 groups (M shaped and non-M-shaped) in gait parameters.
  
  
  CONCLUSIONS
  Evaluation of the vertical ground reaction force to determine its shape may be a useful and simple tool in the analysis of gait and functional performance.
authors.affiliation: Department of Orthopaedic Surgery, Kochi Medical School, Kochi, Japan. takahast@kochi-ms.ac.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Takahashi
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishida
authors.forename: Daisuke
authors.initials: D
authors.lastname: Hirose
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Nagano
authors.forename: Kiyoto
authors.initials: K
authors.lastname: Okumiya
authors.forename: Masanori
authors.initials: M
authors.lastname: Nishinaga
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Doi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018771:Arthralgia / Q000209:etiology / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D035002:Lower Extremity / Q000503:physiopathology; D020370:Osteoarthritis, Knee / Q000150:complications / Q000503:physiopathology*; D016138:Walking / Q000502:physiology*