title: Changes in Knee Osteoarthritis, Symptoms, and Function After Anterior Cruciate Ligament Reconstruction: A 20-Year Prospective Follow-up Study.
abstract: Progression of tibiofemoral (TF) and patellofemoral (PF) osteoarthritis (OA) and changes in knee function more than 15 years after anterior cruciate ligament reconstruction (ACLR) are not well understood.
  
  
  
  To examine the progression of knee OA and changes in symptoms and function in isolated and combined injuries from 15 to 20 years after ACLR.
  
  
  
  Cohort study; Level of evidence, 2.
  
  
  
  A total of 210 subjects with ACLR were prospectively followed. At the 15- and 20-year follow-ups, radiographs were obtained and classified by the Kellgren and Lawrence (K-L) grading system. Symptoms and function were evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS) as well as isokinetic quadriceps and hamstring muscle strength tests.
  
  
  
  There were 168 subjects (80%) who returned for the 20-year follow-up, with a mean (±SD) age of 45 ± 9 years, mean body mass index of 27 ± 4, and median Tegner activity level of 4 (range, 0-9). The prevalence of radiographic TF and PF OA at the 20-year follow-up was 42% and 21%, respectively. Patients with ACL injuries and other combined injuries had significantly higher prevalence of radiographic TF OA compared with those who had isolated ACL injury (P < .0001). There was a 13% increase in radiographic TF OA (P = .001) and an 8% increase in PF OA (P = .015) from the 15- to the 20-year follow-up. A significant deterioration in knee symptoms and function was observed on the KOOS subscales (P ≤ .01), with the exception of quality of life (P = .14), as well as a decrease in quadriceps muscle strength and hamstring muscle strength (P < .0001).
  
  
  
  The prevalence of radiographic TF and PF OA was 42% and 21%, respectively. A significantly higher prevalence of TF OA was found for subjects with combined injuries compared with those who had isolated ACL injury. The majority of the subjects were stable radiographically over the 5 years between follow-ups. A statistically significant deterioration in symptoms and function was noted, but the mean changes were of questionable clinical importance.
authors.affiliation: Norwegian Research Center for Active Rehabilitation, Department of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway Department of Sport Medicine, Norwegian School of Sport Sciences, Oslo, Norway m.a.risberg@nih.no.
authors.forename: May Arna
authors.initials: MA
authors.lastname: Risberg
authors.affiliation: Norwegian Research Center for Active Rehabilitation, Department of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway Oslo and Akerhus University College of Applied Sciences, Institute of Physiotherapy, Oslo, Norway.
authors.forename: Britt Elin
authors.initials: BE
authors.lastname: Oiestad
authors.affiliation: Department of Radiology, Oslo University Hospital, Oslo, Norway.
authors.forename: Ragnhild
authors.initials: R
authors.lastname: Gunderson
authors.affiliation: Department of Orthopedic Surgery, Aleris, Drammen, Norway Department of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway.
authors.forename: Arne Kristian
authors.initials: AK
authors.lastname: Aune
authors.affiliation: Department of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway Oslo Sports Trauma Research Center, Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: Lars
authors.initials: L
authors.lastname: Engebretsen
authors.affiliation: Norwegian Research Center for Active Rehabilitation, Department of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway Institute of Anatomy, Paracelsus Medical University Salzburg and Nuremburg, Salzburg, Austria.
authors.forename: Adam
authors.initials: A
authors.lastname: Culvenor
authors.affiliation: Department of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Inger
authors.initials: I
authors.lastname: Holm
mesh_terms: D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000503:physiopathology / Q000601:surgery; D059549:Anterior Cruciate Ligament Reconstruction; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000503:physiopathology / Q000601:surgery; D000071066:Patient Reported Outcome Measures; D011446:Prospective Studies; D016059:Range of Motion, Articular
keywords: ACL reconstruction; knee function; osteoarthritis