title: Associates of physical function and pain in patients with patellofemoral pain syndrome.
abstract: OBJECTIVE
  To explore whether impairment of muscle strength, soft tissue length, movement control, postural and biomechanic alterations, and psychologic factors are associated with physical function and pain in patients with patellofemoral pain syndrome (PFPS).
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Rehabilitation outpatient.
  
  
  METHODS
  Seventy-four patients diagnosed with PFPS.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Measurements were self-reported function and pain; strength of quadriceps, hip abduction, and hip external rotation; length of hamstrings, quadriceps, plantar flexors, iliotibial band/tensor fasciae latae complex, and lateral retinaculum; foot pronation; Q-angle; tibial torsion; visual observation of quality of movement during a lateral step-down task; anxiety; and fear-avoidance beliefs.
  
  
  RESULTS
  After controlling for age and sex, anxiety and fear-avoidance beliefs about work and physical activity were associated with function, while only fear-avoidance beliefs about work and physical activity were associated with pain.
  
  
  CONCLUSIONS
  Psychologic factors were the only associates of function and pain in patients with PFPS. Factors related to physical impairments did not associate to function or pain. Our results should be validated in other samples of patients with PFPS. Further studies should determine the role of other psychologic factors, and how they relate to anxiety and fear-avoidance beliefs in these patients.
authors.affiliation: Department of Physical Therapy, University of Pittsburgh, Pittsburgh, PA 15260, USA. spiva@pitt.edu
authors.forename: Sara R
authors.initials: SR
authors.lastname: Piva
authors.forename: G Kelley
authors.initials: GK
authors.lastname: Fitzgerald
authors.forename: James J
authors.initials: JJ
authors.lastname: Irrgang
authors.forename: Julie M
authors.initials: JM
authors.lastname: Fritz
authors.forename: Stephen
authors.initials: S
authors.lastname: Wisniewski
authors.forename: Gerald T
authors.initials: GT
authors.lastname: McGinty
authors.forename: John D
authors.initials: JD
authors.lastname: Childs
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Domenech
authors.forename: Scott
authors.initials: S
authors.lastname: Jones
authors.forename: Anthony
authors.initials: A
authors.lastname: Delitto
mesh_terms: D000328:Adult; D001007:Anxiety / Q000523:psychology; D003430:Cross-Sectional Studies; D015444:Exercise / Q000502:physiology / Q000523:psychology; D005239:Fear / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D046788:Patellofemoral Pain Syndrome / Q000503:physiopathology* / Q000523:psychology*; D016059:Range of Motion, Articular / Q000502:physiology; D012959:Socioeconomic Factors