title: The Impact of Demographic, Clinical, Symptom and Psychological Characteristics on the Trajectories of Acute Postoperative Pain After Total Knee Arthroplasty.
abstract: Total knee arthroplasty is a painful procedure. No studies have evaluated modifiable predictors of acute postoperative pain trajectories during hospitalization.
  
  
  
  Consecutive patients (N = 188) were enrolled in a longitudinal cohort study and completed a demographic questionnaire, as well as the Brief Pain Inventory, Hospital Depression and Anxiety Scale, Lee Fatigue Scale, Fatigue Severity Scale, and Brief Illness Perception Questionnaire on the day before surgery. Clinical data were extracted from medical records.
  
  
  
  Each patient completed a pain diary that assessed pain at rest and with activity, and hours per day in pain every evening from day of surgery until postoperative day 3. Using hierarchical linear modeling, we investigated which demographic, clinical, symptom, and psychological characteristics predicted initial levels as well as the trajectories of acute pain at rest and with activity, and hours per day in pain.
  
  
  
  Higher levels of all three acute pain characteristics on the day of surgery resulted in worse trajectories. Higher pain scores with rest and with activity on the day of surgery were associated with more days with femoral block, higher average dose of opioids, and higher emotional response to osteoarthritis. Higher number of comorbidities, higher average dose of opioids, and lower perceived control predicted more hours per day in pain on the day of surgery.
  
  
  
  This study identified several potentially modifiable predictors of worsening pain trajectories following total knee arthroplasty. Optimal pain management warrants identification of these high-risk patients and treatment of modifiable risk factors.
authors.affiliation: Department of Patient Safety and Research, Lovisenberg Diakonale Hospital, Oslo, Norway.|Department of Nursing Science, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Maren Falch
authors.initials: MF
authors.lastname: Lindberg
authors.affiliation: School of Nursing, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Miaskowski
authors.affiliation: Department of Nursing Science, Faculty of Medicine, University of Oslo, Oslo, Norway.|Department of Research and Development, Division of Emergencies and Critical Care, Oslo University Hospital, Oslo, Norway.
authors.forename: Tone
authors.initials: T
authors.lastname: Rustøen
authors.affiliation: Department of Research and Development, Division of Emergencies and Critical Care, Oslo University Hospital, Oslo, Norway.|Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Leiv Arne
authors.initials: LA
authors.lastname: Rosseland
authors.affiliation: School of Nursing, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Paul
authors.affiliation: School of Nursing, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Cooper
authors.affiliation: Department of Patient Safety and Research, Lovisenberg Diakonale Hospital, Oslo, Norway.|Department of Nursing Science, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Anners
authors.initials: A
authors.lastname: Lerdal
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery; D010147:Pain Measurement; D010149:Postoperative Pain / Q000453:epidemiology* / Q000209:etiology* / Q000523:psychology*
keywords: Acute Postoperative Pain; Hierarchical Linear Modeling; Pain at Rest; Pain with Activity; Total Knee Arthroplasty