title: Patient Outcomes and Predictors of Success After Revision Anterior Cruciate Ligament Reconstruction.
abstract: BACKGROUND
  Patient outcomes and predictors of success after revision anterior cruciate ligament (ACL) reconstruction are currently limited in the literature. Existing studies either have a small study size or are difficult to interpret because of the multiple surgeons involved in the care of the study sample.
  
  
  OBJECTIVE
  To determine patient outcomes and predictors of success or failure after a single-stage revision ACL reconstruction by a single fellowship-trained senior surgeon at a single institution.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  A total of 78 patients who underwent revision ACL reconstruction by a single surgeon from 2010 to 2014 were contacted and available for follow-up. The mean time from revision procedure to follow-up was 52 months. Those patients who were able to participate in the study sent in a completed Tegner activity level scale, International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, and IKDC Current Health Assessment Form. The patients' medical records were also thoroughly reviewed.
  
  
  RESULTS
  Five patients had subsequent failure after revision surgery. The median Tegner score was 6 at follow-up, and the mean subjective IKDC score was 72.5. There was no statistically significant difference in outcome scores when comparing revision graft type, body mass index, sex, need for bone grafting, and time from failure to revision. Patients with failures after primary ACL reconstruction secondary to a traumatic event were found to have statistically significantly higher IKDC scores (mean, 76.6) after revision when compared with nontraumatic failures (mean, 67.1), even when controlling for confounders (P < .017).
  
  
  CONCLUSIONS
  Revision ACL reconstruction is effective in improving patient activity levels and satisfaction. However, the subjective IKDC results are quite variable and likely based on multiple factors. Patients with traumatic injuries contributing to graft failure after primary ACL reconstruction had a statistically significantly, although not clinically significant, higher IKDC score after revision surgery compared with nontraumatic failures. These data may be useful when counseling a patient on whether to pursue revision ACL reconstruction surgery.
authors.affiliation: Harvard Medical School, Boston, Massachusetts, USA.; Temple University Health System, Philadelphia, Pennsylvania, USA.; Tufts Medical Center, Boston, Massachusetts, USA.
authors.forename: William R
authors.initials: WR
authors.lastname: Johnson
authors.affiliation: Watson Clinic, Lakeland, Florida, USA.
authors.forename: Amun
authors.initials: A
authors.lastname: Makani
authors.affiliation: Albany Medical College, Albany, New York, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Wall
authors.affiliation: Harvard Medical School, Boston, Massachusetts, USA.; Bioengineering Laboratory, Massachusetts General Hospital, Boston, Massachusetts, USA.
authors.forename: Ali
authors.initials: A
authors.lastname: Hosseini
authors.affiliation: Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Perry
authors.initials: P
authors.lastname: Hampilos
authors.affiliation: Harvard Medical School, Boston, Massachusetts, USA.; Bioengineering Laboratory, Massachusetts General Hospital, Boston, Massachusetts, USA.
authors.forename: Guoan
authors.initials: G
authors.lastname: Li
authors.affiliation: Orthopaedic Surgery, Tufts Medical School, Boston, Massachusetts, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Gill
keywords: anterior cruciate ligament; failure; reconstruction; revision