title: Bilateral measurement of resting calcaneal stance position and tibial varum using digital photography and standardized positioning protocols.
abstract: BACKGROUND
  Excessive calcaneal eversion and tibial varum are thought to predispose individuals to overuse injuries such as patellofemoral pain, yet investigations of this relationship have yielded equivocal results. Differences in the methods used, including stance position, may contribute to the observed differences.
  
  
  METHODS
  Forty-six young adults (29 asymptomatic control patients and 17 patients with patellofemoral pain syndrome) participated. Resting calcaneal stance position and tibial varum were measured using a digital photographic-goniometric method while participants adopted three upright, weightbearing stance positions (self-selected, Romberg, and single-limb right or left). Data were collapsed and analyzed by group (asymptomatic, symptomatic) or limb status (uninjured, injured), stance, and limb (right, left).
  
  
  RESULTS
  Mean resting calcaneal stance position and tibial varum values differed significantly among the three stance conditions, whereas differences between groups, limb status, and limb were not observed. Pearson product moment correlations revealed no relationship between measures derived under the differing stance conditions (r = -0.08 to -0.37, P > .05) and only weak to moderate relationships in resting calcaneal stance position and tibial varum measures between the right and left limbs (r = 0.37 to 0.71, P < .01).
  
  
  CONCLUSIONS
  If differences in reported values for resting calcaneal stance position and tibial varum in an individual, between groups, or from study to study are to be interpreted as true differences or as products of the measurement method used, a standardized measurement method must be established and methods must be accurately reported.
authors.affiliation: School of Health and Human Performance, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Shannon M
authors.initials: SM
authors.lastname: Mahar
authors.forename: Lori A
authors.initials: LA
authors.lastname: Livingston
mesh_terms: D000293:Adolescent; D000328:Adult; D002111:Calcaneus / Q000033:anatomy & histology* / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D010781:Photography / Q000379:methods*; D011187:Posture / Q000502:physiology*; D015203:Reproducibility of Results; D012146:Rest / Q000502:physiology*; D013977:Tibia / Q000033:anatomy & histology* / Q000502:physiology; D055815:Young Adult