title: Between-day reliability of a cluster-based method for multisegment kinematic analysis of the foot-ankle complex.
abstract: BACKGROUND
  Detailed description of foot pronation-supination requires multisegment evaluation of the kinematics of the foot-ankle complex. There are noninvasive methods with independent (single) tracking markers attached directly to the skin. However, these methods are inconsistent with the usual rigid segments assumption. In contrast, using clustered markers is compatible with this assumption and is necessary for analyses that need tracking markers to be distant from the foot (eg, shod walking). This study investigated the between-day reliability of a cluster-based method for multisegment analysis of foot-ankle angles related to pronation-supination.
  
  
  METHODS
  Ten healthy adults participated in the study. An anatomically based, three-dimensional model comprising the shank, calcaneus, and forefoot was created. Rigid clusters of tracking markers were used to determine the relative positions and motions of the segments. Mean positions were measured with the subtalar joint in neutral position during standing. Furthermore, mean angles, peaks, and timings of peaks were measured during the stance phase of walking. All of the variables were measured twice, with a 1-week interval. To evaluate reliability, intraclass correlation coefficients were calculated for discrete variables and coefficients of multiple correlation for entire gait curves.
  
  
  RESULTS
  Intraclass correlation coefficients varied from 0.8 to 0.93 for the angles obtained when the subtalar joint was in neutral and from 0.76 to 0.9 for walking variables. Coefficients of multiple correlation varied from 0.93 to 0.97 for walking curves.
  
  
  CONCLUSIONS
  The method described has good to high reliability and provides a systematic method for multisegment kinematic evaluation of foot-ankle pronation-supination.
authors.forename: Thales R
authors.initials: TR
authors.lastname: Souza
authors.forename: Haroldo L
authors.initials: HL
authors.lastname: Fonseca
authors.forename: Ana Carolina A
authors.initials: AC
authors.lastname: Vaz
authors.forename: Juliana S
authors.initials: JS
authors.lastname: Antero
authors.forename: Cristiano S
authors.initials: CS
authors.lastname: Marinho
authors.forename: Sérgio T
authors.initials: ST
authors.lastname: Fonseca
mesh_terms: D000293:Adolescent; D000328:Adult; D000843:Ankle Joint / Q000502:physiology*; D001696:Biomechanical Phenomena; D016000:Cluster Analysis; D005260:Female; D005528:Foot / Q000502:physiology*; D006801:Humans; D008297:Male; D008954:Models, Biological; D011403:Pronation / Q000502:physiology*; D015203:Reproducibility of Results; D013484:Supination / Q000502:physiology*; D016138:Walking / Q000502:physiology*; D055815:Young Adult