title: Results of revision anterior cruciate ligament reconstruction using a transportal technique.
abstract: BACKGROUND
  As the number of anterior cruciate ligament (ACL) injuries and primary ACL reconstruction surgeries increase, the absolute number of re-ruptures or failures has also subsequently increased. In our study, we look at the causes of failure in the primary surgery and also report the clinical and functional outcomes in our series of patients undergoing revision surgery.
  
  
  METHODS
  We performed a retrospective review of all revision ACL reconstructions performed by the senior author over a 3-year period using a single-stage transportal technique. Causes of failure were elucidated through clinical, radiological and intraoperative assessment. Outcomes of revision surgery were assessed clinically as well as functionally through the use of a variety of subjective knee scores, with a mean follow-up time of 27.5 months (range 12-40).
  
  
  RESULTS
  In our series of 13 patients, all primary surgeries were performed originally via a transtibial technique, with a mean time to failure of 26.4 months (range 6-65). Tunnel malposition was identified as the most common cause of failure (61.5%), while purely traumatic causes accounted for 38.5% of cases. New meniscal injuries were identified in 77% of the patients, and cartilage loss in 38.5%. There was a statistically significant improvement in functional outcomes in all patients following revision surgery, and whilst majority (92%) were able to return to sporting activities on a regular basis, only 54% were able to return to their previous level of sports.
  
  
  CONCLUSIONS
  Tunnel malposition was found to be the most common cause of primary graft failure in our series of patients undergoing revision ACL reconstruction. Concomitant meniscal and cartilage pathologies were also common intraoperative findings. Improved knee stability and functional outcomes can be expected following revision surgery, and majority will be able to return to some form of sporting activity, albeit at lower levels than before for some patients.
authors.forename: Bryan
authors.initials: B
authors.lastname: Wang
authors.forename: Keng Thiam
authors.initials: KT
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007593:Joint Instability / Q000209:etiology / Q000601:surgery*; D007718:Knee Injuries / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012086:Reoperation / Q000379:methods; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult