title: Twenty-year outcomes of a longitudinal prospective evaluation of isolated endoscopic anterior cruciate ligament reconstruction with patellar tendon autografts.
abstract: BACKGROUND
  Long-term prospective follow-up studies of single-incision endoscopic anterior cruciate ligament (ACL) reconstruction are limited and may include confounding factors.
  
  
  OBJECTIVE
  This longitudinal prospective study reports the outcomes of isolated ACL reconstruction using middle-third patellar tendon autografts in 90 patients over 20 years.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  Between January 1993 and April 1994, a total of 90 patients met study inclusion criteria: evaluation at 1, 2, 3, 4, 5, 7, 10, 15, and 20 years after surgery. Exclusion criteria were associated ligamentous injuries requiring surgery, previous meniscectomy or meniscal injuries requiring more than one-third meniscectomy, chondral injuries, and an abnormal contralateral knee.
  
  
  RESULTS
  At 20 years, 32 (36%) patients had sustained another ACL injury: 8 (9%) to the index limb and 27 (30%) to the contralateral limb (3 injuring both knees). The mean International Knee Documentation Committee (IKDC) score was 86. Of the patients, 50% participated in strenuous/very strenuous activities, and kneeling pain was present in 63%. Radiographic degenerative change was found in 61%; 20% had IKDC grade C, and 0% had grade D. The IKDC clinical examination revealed that 95% had a normal/nearly normal knee. Significant sex differences existed: when compared with male patients, female patients were less likely to reinjure the reconstructed ACL (18% vs 2%, respectively; P = .01), reported poorer IKDC subjective scores (90 vs 83, respectively; P = .03), had more activity-related pain (20% vs 57%, respectively; P = .02), and were less likely to participate in strenuous activities (66% vs 35%, respectively; P = .009). ACL graft survival was not related to age. Patients <18 years old had an increased odds ratio (3.2) for rupturing the contralateral ACL. A coronal graft angle <17° increased the risk of failure compared with an angle >17° (77% vs 96% survival, respectively) by a factor of 8.5.
  
  
  CONCLUSIONS
  Injuries more commonly occurred in the contralateral ACL than in the reconstructed ACL graft, and the most significant predictor of a contralateral ACL injury was age <18 years. The most significant predictor of an ACL graft rupture was a coronal graft angle <17°. Female patients had lower rerupture rates, poorer subjective scores, and decreased participation in strenuous activities, putting the graft at a lower risk of failure. Kneeling pain remained persistent over 20 years. Radiographic osteoarthritis was evident in 61% of patients, but symptomatic osteoarthritic symptoms were rarely reported.
authors.affiliation: North Sydney Orthopaedic and Sports Medicine Centre, Sydney, New South Wales, Australia.
authors.forename: Simon
authors.initials: S
authors.lastname: Thompson
authors.affiliation: North Sydney Orthopaedic and Sports Medicine Centre, Sydney, New South Wales, Australia.
authors.forename: Lucy
authors.initials: L
authors.lastname: Salmon
authors.affiliation: North Sydney Orthopaedic and Sports Medicine Centre, Sydney, New South Wales, Australia.
authors.forename: Alison
authors.initials: A
authors.lastname: Waller
authors.affiliation: Castlereagh Imaging, Sydney, New South Wales, Australia.
authors.forename: James
authors.initials: J
authors.lastname: Linklater
authors.affiliation: North Sydney Orthopaedic and Sports Medicine Centre, Sydney, New South Wales, Australia The Mater Hospital, Sydney, New South Wales, Australia.
authors.forename: Justin
authors.initials: J
authors.lastname: Roe
authors.affiliation: North Sydney Orthopaedic and Sports Medicine Centre, Sydney, New South Wales, Australia The Mater Hospital, Sydney, New South Wales, Australia University of Notre Dame, Sydney, New South Wales, Australia lpinczewski@nsosmc.com.au.
authors.forename: Leo
authors.initials: L
authors.lastname: Pinczewski
mesh_terms: D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D001182:Arthroscopy / Q000379:methods*; D064592:Autografts / Q000637:transplantation; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000601:surgery; D007719:Knee Joint / Q000601:surgery; D008297:Male; D020370:Osteoarthritis, Knee / Q000517:prevention & control; D017847:Patellar Ligament / Q000637:transplantation*; D011446:Prospective Studies; D012421:Rupture / Q000601:surgery; D014182:Transplantation, Autologous; D016896:Treatment Outcome
keywords: anterior cruciate ligament (ACL); knee; long-term outcome; reconstruction