title: The effect of remnant preservation on tibial tunnel enlargement in ACL reconstruction with hamstring autograft: a prospective randomized controlled trial.
abstract: OBJECTIVE
  To investigate the effect of remnant preservation on tibial tunnel enlargement in a single-bundle anterior cruciate ligament (ACL) reconstruction with a hamstring autograft.
  
  
  METHODS
  From 2006 to 2009, a total of 62 patients who underwent single-bundle ACL reconstruction with a quadrupled hamstring tendon autograft were enrolled in this study. The patients were randomly divided into two groups: the preserving-remnant group and the removing-remnant group. Plain radiographs were taken at 1 week, and 3, 6, and 24 months postoperatively, and tibial tunnel enlargement was evaluated. The postoperative clinical assessment included the Lysholm rating scale and KT-1000 measurement.
  
  
  RESULTS
  In total, 27 patients in the preserving-remnant group and 24 patients in the removing-remnant group were followed up and the median follow-up was 24.5 months (range 24-27 months). Tibial tunnel enlargement occurred within 6 months postoperatively. Positive enlargement was observed in 8 patients (29.6 %) in the preserving-remnant group and 14 patients (58.3 %) in the removing-remnant group (P = 0.0388). The percentage of tibial tunnel enlargement was 25.7 ± 6.7 and 34.0 ± 8.9 % in the preserving- and removing-remnant groups, respectively (P = 0.0004). In the preserving-remnant group, the average Lysholm score increased from 60.3 ± 5.3 (51-69) to 93.0 ± 3.5 (88-100), and the side-to-side difference of the KT-1000 changed from 6.3 ± 0.9 (5.1-8.0) to 1.4 ± 0.6 (0.5-2.4) mm. In the removing-remnant group, the average Lysholm score increased from 58.7 ± 6.5 (48-71) to 91.1 ± 3.9 (85-100), and the side-to-side difference of the KT-1000 changed from 6.5 ± 0.8 (5.4-8.2) to 1.7 ± 0.6 (0.6-2.8) mm.
  
  
  CONCLUSIONS
  It is confirmed that remnant preservation in ACL reconstruction can resist tibial tunnel enlargement but that this technique does not affect the short-term clinical outcome of ACL reconstruction.
authors.affiliation: Department of Orthapaedic Surgery, The General Hospital of the Jinan Military Command, No. 25, Shifan Road, Jinan, Shandong, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
authors.forename: Xuecheng
authors.initials: X
authors.lastname: Cao
authors.forename: Lifeng
authors.initials: L
authors.lastname: Liu
authors.forename: Ya
authors.initials: Y
authors.lastname: Liu
authors.forename: Rui
authors.initials: R
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D064592:Autografts; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D013710:Tendons / Q000637:transplantation*; D013977:Tibia / Q000601:surgery*; D014182:Transplantation, Autologous; D055815:Young Adult