title: The effect of exercise therapy on knee adduction moment in individuals with knee osteoarthritis: A systematic review.
abstract: BACKGROUND
  Exercise therapy is an evidence-based intervention for the conservative management of knee osteoarthritis. It is hypothesized that exercise therapy could reduce the knee adduction moment. A systematic review was performed in order to verify the effects of exercise therapy on the knee adduction moment in individuals with knee osteoarthritis in studies that also assessed pain and physical function.
  
  
  METHODS
  A comprehensive electronic search was performed on MEDLINE, Cochrane CENTRAL, EMBASE, Google scholar and OpenGrey. Inclusion criteria were randomized controlled trials with control or sham groups as comparator assessing pain, physical function, muscle strength and knee adduction moment during walking at self-selected speed in individuals with knee osteoarthritis that underwent a structured exercise therapy rehabilitation program. Two independent reviewers extracted the data and assessed risk of bias. For each study, knee adduction moment, pain and physical function outcomes were extracted. For each outcome, mean differences and 95% confidence intervals were calculated. Due to clinical heterogeneity among exercise therapy protocols, a descriptive analysis was chosen.
  
  
  RESULTS
  Three studies, comprising 233 participants, were included. None of the studies showed significant differences between strengthening and control/sham groups in knee adduction moment. In regards to pain and physical function, the three studies demonstrated significant improvement in pain and two of them showed increased physical function following exercise therapy compared to controls. Muscle strength and torque significantly improved in all the three trials favoring the intervention group.
  
  
  CONCLUSIONS
  Clinical benefits from exercise therapy were not associated with changes in the knee adduction moment. The lack of knee adduction moment reduction indicates that exercise therapy may not be protective in knee osteoarthritis from a joint loading point of view. Alterations in neuromuscular control, not captured by the knee adduction moment measurement, may contribute to alter dynamic joint loading following exercise therapy. To conclude, mechanisms other than the reduction in knee adduction moment might explain the clinical benefits of exercise therapy on knee osteoarthritis.
authors.affiliation: Masters Program in Rehabilitation Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Brazil. Electronic address: giovannieferreira@hotmail.com.
authors.forename: Giovanni E
authors.initials: GE
authors.lastname: Ferreira
authors.affiliation: Doctoral Program in Health Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Brazil. Electronic address: carollinerobinson@gmail.com.
authors.forename: Caroline Cabral
authors.initials: CC
authors.lastname: Robinson
authors.affiliation: Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Brazil. Electronic address: matheusw.fisio@hotmail.com.
authors.forename: Matheus
authors.initials: M
authors.lastname: Wiebusch
authors.affiliation: Masters Program in Rehabilitation Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Brazil. Electronic address: carolinaviero@gmail.com.
authors.forename: Carolina Cabral de Mello
authors.initials: CC
authors.lastname: Viero
authors.affiliation: Masters Program in Rehabilitation Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Brazil. Electronic address: luisr@ufcspa.edu.br.
authors.forename: Luis Henrique Telles
authors.initials: LH
authors.lastname: da Rosa
authors.affiliation: Masters Program in Rehabilitation Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Brazil; Doctoral Program in Health Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Brazil. Electronic address: marcelofs@ufcspa.edu.br.
authors.forename: Marcelo Faria
authors.initials: MF
authors.lastname: Silva
mesh_terms: D005081:Exercise Therapy; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D053580:Muscle Strength / Q000502:physiology; D020370:Osteoarthritis, Knee / Q000503:physiopathology* / Q000628:therapy*; D010146:Pain / Q000503:physiopathology / Q000517:prevention & control; D010147:Pain Measurement
keywords: Exercise therapy; Knee adduction moment; Knee osteoarthritis; Systematic review