title: Effects of Remnant Tissue Preservation on Clinical and Arthroscopic Results After Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction.
abstract: BACKGROUND
  Clinical utility of remnant tissue preservation after single-bundle anterior cruciate ligament (ACL) reconstruction has not been established. In addition, no studies have evaluated the clinical utility of remnant preservation after anatomic double-bundle ACL reconstruction.
  
  
  OBJECTIVE
  The study hypotheses were as follows: (1) Subjective and functional clinical results may be comparable between anatomic double-bundle reconstructions that preserve the remnant tissue and those that resect the remnant tissue, (2) postoperative knee stability and the second-look arthroscopic evaluation may be significantly more favorable with the remnant-preserving reconstruction, and (3) the degree of the initial graft coverage may significantly affect postoperative knee stability.
  
  
  METHODS
  Cohort study; Level of evidence, 2.
  
  
  METHODS
  A total of 179 patients underwent anatomic double-bundle ACL reconstruction. Based on the Crain classification of ACL remnant tissue, 81 patients underwent the remnant-preserving procedure (group P) and the remaining 98 patients underwent the remnant-resecting procedure (group R). There were no differences between the 2 groups concerning all background factors, including preoperative knee instability and intraoperative tunnel positions. The patients were followed for 2 years or more.
  
  
  RESULTS
  The subjective and functional clinical results were comparable between the 2 reconstruction procedures. Side-to-side anterior laxity was significantly less (P = .0277) in group P (0.9 mm) than in group R (1.5 mm). The pivot-shift test was negative in 89% of group P and 78% of group R patients; the result for group R was significantly lower (P = .0460). In the arthroscopic observations, results for group P were significantly better than for group R concerning postoperative laceration and fibrous tissue coverage of the grafts (P = .0479).
  
  
  CONCLUSIONS
  Remnant preservation in anatomic double-bundle ACL reconstruction did not significantly improve subjective and functional results in the short-term evaluation, but it significantly improved postoperative knee stability. The degree of initial graft coverage significantly affected postoperative knee stability.
authors.affiliation: Department of Sports Medicine and Joint Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan Department of Advanced Therapeutic Research for Sports Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan eijik@med.hokudai.ac.jp.
authors.forename: Eiji
authors.initials: E
authors.lastname: Kondo
authors.affiliation: Department of Sports Medicine and Joint Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Yasuda
authors.affiliation: Department of Sports Medicine and Joint Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Onodera
authors.affiliation: Department of Sports Medicine and Joint Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Kawaguchi
authors.affiliation: Department of Sports Medicine and Joint Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors.forename: Nobuto
authors.initials: N
authors.lastname: Kitamura
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D001182:Arthroscopy / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000601:surgery; D007719:Knee Joint / Q000601:surgery*; D022125:Lacerations / Q000503:physiopathology; D008297:Male; D011446:Prospective Studies; D024162:Second-Look Surgery; D019737:Transplants; D055815:Young Adult
keywords: anterior cruciate ligament; double-bundle reconstruction; knee ligaments; remnant tissue