title: Nonlinear analysis of postural sway in subjects with below knee amputation during opened and closed eye conditions.
abstract: OBJECTIVE
  The aim of this study was to compare the structure of postural sway in healthy people and amputees with SACH foot (solid ankle cushion heel) and single axis foot during standing.
  
  
  METHODS
  Twenty healthy, 10 amputees with single axis foot, and 10 amputees with SACH foot participated in this study. The structure of postural sway of the subjects was evaluated using approximate entropy (ApEn).
  
  
  RESULTS
  People with SACH foot prosthesis exhibit increased regularity in postural sway compared to healthy people and people with single axis foot.
  
  
  CONCLUSIONS
  Amputees who used single axis prosthesis achieved appropriate adaptation to their prosthesis device.
authors.affiliation: Physical Therapy Department, Rehabilitation Faculty, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Meissam
authors.initials: M
authors.lastname: Sadeghisani
authors.affiliation: Musculoskeletal Research Center, Rehabilitation Faculty, Isfahan University of Medical Sciences, Iran.
authors.forename: Mohammad Taghi
authors.initials: MT
authors.lastname: Karimi
authors.affiliation: Musculoskeletal Research Center, Rehabilitation Faculty, Isfahan University of Medical Sciences, Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Kamali
keywords: Balance; Below knee amputee; Force plate; SACH foot; Single axis foot