title: Healing of tibial bone tunnels after bone grafting for staged revision anterior cruciate ligament surgery: A prospective computed tomography analysis.
abstract: OBJECTIVE
  To quantify healing of tibial bone tunnels after bone grafting in two-stage ACL reconstruction revision.
  
  
  METHODS
  Ten consecutive patients underwent autogenous bone grafting prior to ACL reconstruction revision (four females and six males, average age 28years). The indications for two-stage surgery were as follows: (1) the enlargement of the tibial tunnel aperture was >20mm in diameter or, (2) the existing tunnel was overlapped with the optimal tunnel and positioned more than a half tunnel diameter posterior to the optimal position. An autogenous iliac bone block was driven into a new tunnel. CT examinations were performed at three, 12 and 24weeks after bone grafting. Evaluations were performed on 15 axial planes at one-millimeter intervals from the articular surface perpendicular to the long axis of the tibia using the following three parameters: occupying ratio (OR), union ratio (UR), and bone mineral density (BMD) of grafted bone.
  
  
  RESULTS
  The average ORs were 81, 85 and 94%, and the average URs were 49, 75 and 89% at three, 12 and 24weeks, respectively. Each parameter significantly increased over time. The average BMD was 510 and 571mg/cm(3) at 12 and 24weeks, respectively, with a significantly higher value at 24weeks.
  
  
  CONCLUSIONS
  The average ORs, URs and BMD at 24weeks after bone grafting were higher than those at 12weeks, which suggests that at 24weeks after bone grating, the condition of the patients' beds becomes favorable for safe implantation and fixation of ACL graft revision.
  
  
  METHODS
  Case series Level IV.
authors.affiliation: Department of Orthopaedic Sports Medicine, Seifu Hospital, Osaka, Japan; Department of Orthopaedic Sports Medicine, Kansai Rosai Hospital, Hyogo, Japan. Electronic address: uchida3847@gmail.com.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Uchida
authors.affiliation: Department of Orthopaedic Sports Medicine, Kansai Rosai Hospital, Hyogo, Japan.
authors.forename: Yukiyoshi
authors.initials: Y
authors.lastname: Toritsuka
authors.affiliation: Department of Orthopaedics, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Mae
authors.affiliation: Department of Orthopaedic Sports Medicine, Kansai Rosai Hospital, Hyogo, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Kusano
authors.affiliation: Department of Orthopaedic Sports Medicine, Kansai Rosai Hospital, Hyogo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ohzono
mesh_terms: D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D015519:Bone Density; D016025:Bone Transplantation; D005260:Female; D017102:Fracture Healing; D006801:Humans; D007085:Ilium / Q000637:transplantation; D008297:Male; D011446:Prospective Studies; D012086:Reoperation; D013977:Tibia / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D014057:Tomography, X-Ray Computed
keywords: ACL reconstruction revision; Bone healing; Bone mineral density; Iliac bone grafting; Two-staged ACL reconstruction revision