title: Mechanical symptoms as an indication for knee arthroscopy in patients with degenerative meniscus tear: a prospective cohort study.
abstract: According to prevailing consensus, patients with mechanical symptoms are those considered to most likely benefit from arthroscopic surgery. The aim of this study was to determine the value of using patients' pre-operative self-reports of mechanical symptoms as a justification surgery in patients with degenerative meniscus tear/knee disease.
  
  
  
  Pragmatic prospective cohort of 900 consecutive patients with symptomatic degenerative knee disease and meniscus tear undergoing arthroscopic partial meniscectomy (APM) was collected from one public orthopedic referral center specialized in arthroscopic surgery during 2007-2011. The patients' subjective satisfaction, self-rated improvement, change in Western Ontario Meniscal Evaluation Tool (WOMET) score, and patients' ratings of the knee using a numerical rating scale (NRS) was assessed at 1 year postoperatively. Multivariable regression models, adjusted for possible confounders and intermediates, were used to compare the outcomes in those with and without preoperative mechanical symptoms.
  
  
  
  The proportion of patients satisfied with their knee 12 months after arthroscopy was significantly lower among those with preoperative mechanical symptoms than among those without (61% vs 75%, multivariable adjusted risk ratio [RR] 0.84; 95% confidence interval [CI] 0.76, 0.92). Similarly, the proportion reporting improvement was lower (RR 0.91; 95% CI 0.85, 0.97). No statistically significant difference was found in change in WOMET or NRS between the two groups. Of those with preoperative mechanical symptoms, 47% reported persistent symptoms at 12 months postoperatively.
  
  
  
  Our observational data contradicts the current tenet of using patients' self-report of mechanical symptoms as a justification for performing arthroscopic surgery on patients with degenerative meniscus tear.
authors.affiliation: Department of Orthopaedics and Traumatology, Hatanpää Hospital and University of Tampere, Tampere, Finland. Electronic address: raine.sihvonen@fimnet.fi.
authors.forename: R
authors.initials: R
authors.lastname: Sihvonen
authors.affiliation: Orthopaedics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden; Clinical Epidemiology Research and Training Unit, Boston University School of Medicine, Boston, MA, USA. Electronic address: martin.englund@med.lu.se.
authors.forename: M
authors.initials: M
authors.lastname: Englund
authors.affiliation: Orthopaedics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden. Electronic address: aleksandra.j.turkiewicz@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: Turkiewicz
authors.affiliation: Department of Orthopaedics and Traumatology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland. Electronic address: teppo.jarvinen@helsinki.fi.
authors.forename: T L N
authors.initials: TL
authors.lastname: Järvinen
mesh_terms: D001182:Arthroscopy; D006801:Humans; D008592:Menisci, Tibial; D009864:Ontario; D011446:Prospective Studies; D012421:Rupture
keywords: Degenerative knee; Knee arthroscopy; Mechanical symptoms; Meniscus