title: The importance of perceived helplessness and emotional health in understanding the relationship among pain, function, and satisfaction following revision knee replacement surgery.
abstract: OBJECTIVE
  Little is known about the relationships among pain, function, psychological variables like perceived helplessness and emotional health, and patient satisfaction in people with revision knee replacement surgery. We hypothesized that pain and function would have a direct association with satisfaction as well as an indirect association through patient perceptions of helplessness and emotional health.
  
  
  METHODS
  This longitudinal study included 145 participants undergoing revision knee replacement surgery. Demographic data and expectation of benefit from surgery were recorded prior to surgery. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Arthritis Helplessness Scale (AHS) and the Mental Component Scale (MCS) of the SF-36 (emotional health) were collected prior to and 2 years post-surgery. Satisfaction was recorded 2 years post-surgery. Regression analyses were conducted to test for mediation effects of helplessness and MCS.
  
  
  RESULTS
  Participants were on average 69 years old and 54% were women. Participants were satisfied with the results of the surgery (mean ± standard deviation (SD) = 70.42 ± 31.46). Less pain and functional disability were associated with increased patient satisfaction and, the effect of pain or function was also mediated through helplessness whereby more pain and disability were associated with perceptions of helplessness and helplessness was associated with lower satisfaction. MCS did not mediate the relationship of pain and function with satisfaction.
  
  
  CONCLUSIONS
  Helplessness plays an important role in understanding patient satisfaction. Interventions aimed at improving patient outcome should target not only pain and function but also should address strategies to support people in managing following knee revision surgery to maximize satisfaction with outcome.
authors.affiliation: Division of Health Care and Outcomes Research, Toronto Western Research Institute, University Health Network, Toronto, ON, Canada. viji.venkataramanan@uhnresearch.ca
authors.forename: V
authors.initials: V
authors.lastname: Venkataramanan
authors.forename: M A
authors.initials: MA
authors.lastname: Gignac
authors.forename: M
authors.initials: M
authors.lastname: Dunbar
authors.forename: D
authors.initials: D
authors.lastname: Garbuz
authors.forename: J
authors.initials: J
authors.lastname: Gollish
authors.forename: A
authors.initials: A
authors.lastname: Gross
authors.forename: D
authors.initials: D
authors.lastname: Hedden
authors.forename: S J
authors.initials: SJ
authors.lastname: MacDonald
authors.forename: N N
authors.initials: NN
authors.lastname: Mahomed
authors.forename: E
authors.initials: E
authors.lastname: Schemitsch
authors.forename: A M
authors.initials: AM
authors.lastname: Davis
mesh_terms: D000328:Adult; D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000523:psychology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000523:psychology* / Q000601:surgery; D010146:Pain / Q000523:psychology* / Q000601:surgery; D017060:Patient Satisfaction; D020127:Recovery of Function; D012086:Reoperation; D011795:Surveys and Questionnaires