title: Osteoarthritis prevalence following anterior cruciate ligament reconstruction: a systematic review and numbers-needed-to-treat analysis.
abstract: OBJECTIVE
  To determine the prophylactic capability of anterior cruciate ligament (ACL) reconstruction in decreasing the risk of knee osteoarthritis (OA) when compared with ACL-deficient patients, as well as the effect of a concomitant meniscectomy. We also sought to examine the influence of study design, publication date, and graft type as well as the magnitude of change in physical activity from preinjury Tegner scores in both cohorts.
  
  
  METHODS
  We searched Web of Science and PubMed databases from 1960 through 2012 with the search terms osteoarthritis, meniscectomy, anterior cruciate ligament, anterior cruciate ligament reconstruction, and anterior cruciate ligament deficient.
  
  
  METHODS
  Articles that reported the prevalence of tibiofemoral or patellofemoral OA based on radiographic assessment were included. We calculated numbers needed to treat and relative risk reduction with associated 95% confidence intervals for 3 groups (1) patients with meniscal and ACL injury, (2) patients with isolated ACL injury, and (3) total patients (groups 1 and 2).
  
  
  METHODS
  A total of 38 studies met the criteria. Of these, 27 assessed the presence of tibiofemoral osteoarthritis in patients treated with anterior cruciate ligament reconstruction.
  
  
  RESULTS
  Overall, ACL reconstruction (ACL-R) yielded a numbers needed to treat to harm of 16 with a relative risk increase of 16%. Anterior cruciate ligament reconstruction along with meniscectomy yielded a numbers needed to treat to benefit of 15 and relative risk reduction of 11%. Isolated ACL-R showed a numbers needed to treat to harm of 8 and relative risk increase of 43%. Activity levels were decreased in both ACL-R (d = -0.90; 95% confidence interval = 0.77, 1.13) and ACL-deficient (d = -1.13; 95% confidence interval = 0.96, 1.29) patients after injury.
  
  
  CONCLUSIONS
  The current literature does not provide substantial evidence to suggest that ACL-R is an adequate intervention to prevent knee osteoarthritis. With regard to osteoarthritis prevalence, the only patients benefiting from ACL-R were those undergoing concomitant meniscectomy with reconstruction.
authors.affiliation: Neuromuscular Research Laboratory, Department of Exercise and Sports Science, University of North Carolina at Chapel Hill;
authors.forename: Brittney
authors.initials: B
authors.lastname: Luc
authors.forename: Phillip A
authors.initials: PA
authors.lastname: Gribble
authors.forename: Brian G
authors.initials: BG
authors.lastname: Pietrosimone
mesh_terms: D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000009:adverse effects / Q000379:methods; D006801:Humans; D007718:Knee Injuries / Q000601:surgery*; D020370:Osteoarthritis, Knee / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D010043:Outcome and Process Assessment, Health Care; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control; D015995:Prevalence
keywords: absolute risk reduction; activity level; knee; meniscectomy