title: Contribution of altered hip, knee and foot kinematics to dynamic postural impairments in females with patellofemoral pain during stair ascent.
abstract: BACKGROUND
  Altered hip, knee and foot kinematics have been systematically observed in individuals with patellofemoral pain (PFP). However, less attention has been given to the altered dynamic postural control associated with PFP. Additionally, the relative contribution of kinematic impairments to the postural behavior of subjects with PFP remains an open question that warrants investigation. The aims of this study were: i) to investigate possible differences in hip adduction, rearfoot eversion, knee flexion and displacement area of the center of pressure (COP) in individuals with PFP in comparison to controls during stair ascent; and (ii) to determine which kinematic parameter is the best predictor of the displacement area of the COP measured during the stance phase of the stair ascent.
  
  
  METHODS
  Twenty-nine females with PFP and 25 asymptomatic pain-free females underwent three-dimensional kinematic and COP analyses during stair ascent. Between-group comparisons were made using independent t-tests. Regression models were performed to identify the capability of each kinematic factor in predicting the displacement area of the COP.
  
  
  RESULTS
  Reduced knee flexion and displacement area of the COP as well as increased peak hip adduction and peak rearfoot eversion were observed in individuals with PFP as compared to controls. Peak hip adduction was the best predictor of the displacement area of the COP (r(2)=23.4%).
  
  
  CONCLUSIONS
  The excessive hip adduction was the biggest predictor of the displacement area of the COP.
  
  
  CONCLUSIONS
  Based on our findings, proximally targeted interventions may be of major importance for the functional reestablishment of females with PFP.
authors.affiliation: Physical Therapy Department, School of Science and Technology, University of São Paulo State, Presidente Prudente, Brazil.
authors.forename: Danilo
authors.initials: D
authors.lastname: de Oliveira Silva
authors.affiliation: School of Arts, Sciences, and Humanities, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Fernando Henrique
authors.initials: FH
authors.lastname: Magalhães
authors.affiliation: Physical Therapy Department, School of Science and Technology, University of São Paulo State, Presidente Prudente, Brazil.
authors.forename: Marcella Ferraz
authors.initials: MF
authors.lastname: Pazzinatto
authors.affiliation: Physical Therapy Department, School of Science and Technology, University of São Paulo State, Presidente Prudente, Brazil.
authors.forename: Ronaldo Valdir
authors.initials: RV
authors.lastname: Briani
authors.affiliation: Physical Therapy Department, School of Science and Technology, University of São Paulo State, Presidente Prudente, Brazil.
authors.forename: Amanda Schenatto
authors.initials: AS
authors.lastname: Ferreira
authors.affiliation: Physical Therapy Department, State University of West Parana, Cascavel, Parana, Brazil.
authors.forename: Fernando Amâncio
authors.initials: FA
authors.lastname: Aragão
authors.affiliation: Physical Therapy Department, School of Science and Technology, University of São Paulo State, Presidente Prudente, Brazil. Electronic address: micolis@fct.unesp.br.
authors.forename: Fábio Mícolis
authors.initials: FM
authors.lastname: de Azevedo
mesh_terms: D000293:Adolescent; D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D005528:Foot / Q000503:physiopathology*; D006615:Hip / Q000503:physiopathology*; D006801:Humans; D007717:Knee / Q000503:physiopathology*; D010147:Pain Measurement; D046788:Patellofemoral Pain Syndrome / Q000503:physiopathology*; D004856:Postural Balance / Q000502:physiology*; D016059:Range of Motion, Articular; D055815:Young Adult
keywords: Center of pressure; Knee injury; Patellofemoral joint; Postural control; Regression analysis