title: Anterior laxity and patient-reported outcomes 7 years after ACL reconstruction with a fresh-frozen tibialis allograft.
abstract: OBJECTIVE
  After reconstructing a torn ACL with a soft tissue allograft, the long-term healing process of graft maturation following the short-term healing process of graft incorporation into the bone tunnels might lead to recurring instability and concomitant decreases in the activity level, function, and patient satisfaction. Relying on roentgen stereophotogrammetric analysis (RSA), the primary purpose was to determine whether anterior laxity increased and whether patient-reported outcomes declined between 1 and 7 years for a particular graft construct, surgical technique, and rehabilitation programme.
  
  
  METHODS
  Eighteen of 19 patients, who participated in an earlier RSA study which extended to 1 year after the surgical procedure, were contacted 7 years after the surgical procedure. An examiner, different from the treating surgeon, measured anterior laxity under 150 N of anterior force using RSA in 16 patients and obtained outcome scores in 17 patients. One patient moved abroad and could not be contacted. One patient reinjured his reconstructed ACL and was excluded.
  
  
  RESULTS
  The average increase in anterior laxity of 1.5 ± 2.1 mm between 1 and 7 years after surgery was not significant (p = 0.08), and the average increase in anterior laxity of 2.7 ± 2.3 mm between the day of surgery and 7 years was significant (p < 0.001). There were no significant declines in activity (median Tegner score, 6 at 1 year, 6 at 7 years), function (average Lysholm score, 94 at 1 year, 91 at 7 years), and subjective satisfaction (average International Knee Documentation Committee score, 90 at 1 year, 87 at 7 years) between 1 and 7 years after surgery.
  
  
  CONCLUSIONS
  In demonstrating that the ACL graft construct remains functional in the long term, this study supports the use of a fresh-frozen tibialis allograft in patients with an average age of 37 years at the time of surgery when used in conjunction with a surgical technique which avoids roof and PCL impingement, uses slippage-resistant fixation devices, and allows brace-free, self-paced rehabilitation.
  
  
  METHODS
  IV.
authors.affiliation: Biomedical Engineering Graduate Group, University of California, Davis, CA, 95616, USA.
authors.forename: Emily
authors.initials: E
authors.lastname: Meike
authors.affiliation: Department of Biomedical Engineering, Biomedical Engineering Graduate Group, University of California, Davis, CA, 95616, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Howell
authors.affiliation: Department of Mechanical Engineering, Department of Biomedical Engineering, Biomedical Engineering Graduate Group, University of California, Davis, CA, 95616, USA. mlhull@ucdavis.edu.
authors.forename: M L
authors.identifier: http://orcid.org/0000-0001-8305-4589
authors.initials: ML
authors.lastname: Hull
mesh_terms: D000293:Adolescent; D000328:Adult; D064591:Allografts; D000070598:Anterior Cruciate Ligament Injuries / Q000000981:diagnostic imaging / Q000534:rehabilitation / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods* / Q000534:rehabilitation; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000534:rehabilitation / Q000601:surgery*; D007719:Knee Joint / Q000601:surgery; D008297:Male; D008875:Middle Aged; D000071066:Patient Reported Outcome Measures; D017060:Patient Satisfaction; D059869:Radiostereometric Analysis; D014184:Transplantation, Homologous; D055815:Young Adult
keywords: Anterior cruciate ligament; Graft maturation; Ligamentization; Long-term follow-up; Roentgen stereophotogrammetry