title: The incidence and impact of arthroscopy in the year prior to total knee arthroplasty.
abstract: BACKGROUND
  Prior knee surgery and arthroscopy is known to increase complications and re-operations in subsequent total knee arthroplasty (TKA). We set out to examine the time dependant effect of arthroscopy on Patient Reported Outcome Measures following subsequent TKA.
  
  
  METHODS
  A retrospective review of theatre and clinical records identified 186 patients who underwent TKA within a year of arthroscopy (2009-2013). Oxford knee score (OKS) data was compared with a published cohort from the same department (1708 patients).
  
  
  RESULTS
  One hundred and eighty six patients were identified who underwent TKA within a year of arthroscopy; 112 females, 74 males; mean age 64 (SD 10); mean BMI 31.4 (SD 4.6). There was no significant difference between groups with respect to sex, age, BMI, or pre-operative OKS. One hundred and three patients underwent TKA within six months of arthroscopy. This group had a significant reduction in OKS compared to the previously published cohort (32.8 vs 36.3, p<0.005). There was no significant difference in OKS when TKA was performed more than six months after arthroscopy (35.3). The re-operation rate was 14% in the arthroscopy group, with a revision rate of 3.8% vs 1.6% in a previously published large cohort from the same institution.
  
  
  CONCLUSIONS
  There appears to be a negative impact of arthroscopy in relation to subsequent TKA which seems to be time dependent. TKA should not routinely be performed within six months of arthroscopy. This should inform guidelines on the management knee osteoarthritis.
authors.affiliation: Department of Orthopaedic Surgery, Chorley District Hospital, Lancashire Teaching Hospitals NHS Trust, Preston, United Kingdom. Electronic address: bartonsi@hotmail.com.
authors.forename: S B
authors.initials: SB
authors.lastname: Barton
authors.affiliation: Department of Orthopaedic Surgery, Chorley District Hospital, Lancashire Teaching Hospitals NHS Trust, Preston, United Kingdom.
authors.forename: G J
authors.initials: GJ
authors.lastname: McLauchlan
authors.affiliation: Department of Orthopaedic Surgery, Chorley District Hospital, Lancashire Teaching Hospitals NHS Trust, Preston, United Kingdom.
authors.forename: S J
authors.initials: SJ
authors.lastname: Canty
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D001182:Arthroscopy; D005260:Female; D006801:Humans; D015994:Incidence; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D000071066:Patient Reported Outcome Measures; D012086:Reoperation; D012189:Retrospective Studies
keywords: Arthroscopy; Outcomes; Total knee arthroplasty