title: MRI analysis of single-, double-, and triple-bundle anterior cruciate ligament grafts.
abstract: OBJECTIVE
  The purpose of the study was to evaluate the entire course of ACL grafts on coronal oblique MR images, focusing on differences in graft morphology and graft-to-tunnel healing among single-bundle (SB), double-bundle (DB), and triple-bundle (TB) reconstructions.
  
  
  METHODS
  Eighty-three patients underwent anatomical ACL reconstruction using the semitendinosus tendon. SB reconstruction was performed on 20 patients, DB on 29 patients, and TB on 34 patients. The anteromedial-bundle (AMB) and posterolateral-bundle (PLB) images were extracted from coronal oblique images of grafts at 6 months to visualize their entire course. Signal intensity of grafts was measured independently in three regions: (1) intra-femoral tunnel region, (2) intra-articular region, and (3) intra-tibial tunnel region, followed by calculation of the signal-to-noise quotient (SNQ). To evaluate graft-to-tunnel healing, T2-weighted images were examined for the presence of a high signal-intensity lesion between the graft and bone tunnel around the tunnel aperture.
  
  
  RESULTS
  AMB images showed that SB graft was thick throughout the entire course, while DB graft was thinner than SB graft. TB graft showed a fan shape approaching the tibial tunnels. The SNQ in the femoral tunnel of SB graft was significantly lower than in the DB and TB grafts. High signal-intensity lesions were frequently observed around the femoral tunnel aperture in PLB images of DB and TB grafts compared to SB grafts.
  
  
  CONCLUSIONS
  Gross morphology of TB grafts resembled that of the natural ACL. However, the graft-to-tunnel healing around the femoral tunnel seemed to be insufficient in PLB images of DB and TB compared to SB grafts.
authors.affiliation: Department of Sports Orthopedics, Osaka Rosai Hospital, 1179-3 Nagasone-cho, Kita-ku, Sakai, Osaka, 583-8555, Japan, yoshi-tanaka@iris.eonet.ne.jp.
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Yasukazu
authors.initials: Y
authors.lastname: Yonetani
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Shiozaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanamoto
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kita
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Amano
authors.forename: Masashi
authors.initials: M
authors.lastname: Kusano
authors.forename: Masashi
authors.initials: M
authors.lastname: Hirakawa
authors.forename: Shuji
authors.initials: S
authors.lastname: Horibe
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013710:Tendons / Q000637:transplantation*; D013848:Thigh; D013977:Tibia / Q000601:surgery; D016896:Treatment Outcome