title: Comparison of the Modified Transtibial Technique, Anteromedial Portal Technique and Outside-in Technique in ACL Reconstruction.
abstract: OBJECTIVE
  To compare clinical and radiographic results of anterior cruciate ligament (ACL) reconstruction using modified transtibial technique (mTT), anteromedial (AM) portal technique and outside-in (OI) technique.
  
  
  METHODS
  From March 2007 to December 2012, ACL reconstruction was performed using the mTT, AM portal technique and OI technique in 20 patients each. Anteroposterior and rotational stability were assessed using the GNRB arthrometer and pivot-shift test. Femoral tunnel obliquity was measured on the anteroposterior and lateral radiographs.
  
  
  RESULTS
  Tegner score, Lysholm score, International Knee Documentation Committee score, pivot-shift test were improved at final follow-up in all three groups. However, statistical difference was not shown. Side-to-side difference in GNRB arthrometer was average of 1.4 mm, 1.0 mm and 0.9 mm in mTT, AM and OI group, showing the signicant difference between mTT and AM/OI groups (p<0.001). The mean femoral tunnel obliquity was 56.4° in the mTT group, 39.4° in the AM group and 33.6° in the OI group, showing significant intergroup difference (p<0.001). It showed the significant difference among three groups (p<0.001).
  
  
  CONCLUSIONS
  Clinical results were improved in all three groups. Femoral tunnel obliquity in AM and OI were more horizontal on the coronal plane. They are thought to have more benefits in oblique positioning of the grafted ACL in rotational stability; however, there was no significant difference among three techniques in pivot-shift test to assess the rotational stability in this study.
authors.affiliation: Department of Orthopedic Surgery, Yeungnam University Medical Center, Daegu, Korea.
authors.forename: Oog Jin
authors.initials: OJ
authors.lastname: Sohn
authors.affiliation: Department of Orthopedic Surgery, Yeungnam University Medical Center, Daegu, Korea.
authors.forename: Dong Chul
authors.initials: DC
authors.lastname: Lee
authors.affiliation: Department of Orthopedic Surgery, Yeungnam University Medical Center, Daegu, Korea.
authors.forename: Kang Hyun
authors.initials: KH
authors.lastname: Park
authors.affiliation: Department of Orthopedic Surgery, Yeungnam University Medical Center, Daegu, Korea.
authors.forename: Hyo Sae
authors.initials: HS
authors.lastname: Ahn
keywords: Anterior cruciate ligament; Knee; Reconstruction; Rotational stability