title: Computed tomography value and tunnel enlargement of round and rounded rectangular femoral bone tunnel for anterior cruciate ligament reconstruction.
abstract: BACKGROUND
  We developed a novel technique for anatomical single-bundle anterior cruciate ligament (ACL) reconstruction: creation of a rounded rectangular femoral bone tunnel. The purpose of this study was to compare the computed tomography (CT) value and tunnel enlargement ratio of the femoral bone tunnel with those of round tunnel ACL reconstruction.
  
  
  METHODS
  We included 39 knees that underwent round tunnel ACL reconstruction and 42 that underwent rounded rectangular ACL reconstruction. To evaluate the CT value, we compared the CT images approximately 1 week after surgery. Making a parallel slice toward the opening of bone tunnels to a depth of 3 mm, we evaluated the CT value of eight directions in the bone tunnel wall. To evaluate tunnel enlargement, we compared CT images approximately 1 week after surgery with images taken 3 months after surgery. Using a parallel slice toward the opening of the bone tunnel, we measured the bone tunnel area and calculated the tunnel enlargement ratio. The level of significance was P < 0.05, and the t test was used for statistical analyses.
  
  
  RESULTS
  The CT value was significantly increased for the rounded rectangular tunnel in comparison with the round tunnel in almost all directions (P < 0.05). The rounded rectangular tunnel area enlargement ratio was significantly lower (round, 110 ± 38 %; rounded rectangular, 73 ± 37 %; P = 0.001).
  
  
  CONCLUSIONS
  The rounded rectangular tunnel could have a compression effect on the cancellous bone and reduce enlargement of the bone tunnel.
authors: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, 13-1, Takara-machi, Kanazawa, Ishikawa, 920-8641, Japan.
authors: Yasushi
authors: Y
authors: Takata
authors: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, 13-1, Takara-machi, Kanazawa, Ishikawa, 920-8641, Japan. nakase1007@yahoo.co.jp.
authors: Junsuke
authors: J
authors: Nakase
authors: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, 13-1, Takara-machi, Kanazawa, Ishikawa, 920-8641, Japan.
authors: Hitoaki
authors: H
authors: Numata
authors: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, 13-1, Takara-machi, Kanazawa, Ishikawa, 920-8641, Japan.
authors: Takeshi
authors: T
authors: Oshima
authors: Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, 13-1, Takara-machi, Kanazawa, Ishikawa, 920-8641, Japan.
authors: Hiroyuki
authors: H
authors: Tsuchiya
mesh_terms: D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries / Q000175:diagnosis / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
keywords: ACL reconstruction; Bone tunnel enlargement; Computed tomography value; Dilation; Rounded rectangular femoral bone tunnel