title: Axial perspective to find the largest intraosseous space available for percutaneous screw fixation of fractures of the acetabular anterior column.
abstract: OBJECTIVE
  To find the largest screw path in the acetabular anterior column using a novel method of axial perspective and test the clinical feasibility of the anterior column axial view projection.
  
  
  METHODS
  3D models with the inner triangular patches deleted were created from the pelvic CT scan data of 58 normal pelvises. The transparency of each 3D model was downgraded at the axial perspective (the view perpendicular to the cross section of the anterior column axis) so that a translucent area was seen clearly. The orientations of each 3D model were adjusted until a triangle-like translucent area that could accommodate the largest virtual screw (Screw I) was present and then an ellipse-like translucent area that could accommodate the two largest virtual screws (Screw II) was present. The maximum diameter, direction of Screw I and the maximum diameter Screw II were measured. Clinical feasibility of the axial view projection was next tested in five cadaveric specimens.
  
  
  RESULTS
  The mean maximum diameters of Screw I and Screw II were 11.20 ± 1.73 (7.80-14.60 mm) and 8.71 ± 0.91 (6.60-10.60 mm), respectively. The angles of Screw I to the transverse, coronal and sagittal planes were 41.16° ± 4.59°, 18.18° ± 1.15° and 44.33° ± 4.31°, respectively. Translucent areas were successfully observed in all the cadaveric hemi-pelves and guide pins were successfully inserted in all the cadaveric hemi-pelves with the assistance of the anterior column axial view projection without cortex penetration or joint violation.
  
  
  CONCLUSIONS
  The acetabular anterior column could safely accommodate not only one 7.3-mm screw, but also two 6.5-mm screws. The anterior column axial projection may be clinically feasible.
authors.affiliation: Department of Orthopedic Trauma, Nanfang Hospital, Southern Medical University, No. 1838 North Guangzhou Avenue, Guangzhou, 510515, China.
authors.forename: XiaoReng
authors.initials: X
authors.lastname: Feng
authors.forename: JinTao
authors.initials: J
authors.lastname: Fang
authors.forename: Chaowen
authors.initials: C
authors.lastname: Lin
authors.forename: Sheng
authors.initials: S
authors.lastname: Zhang
authors.forename: WenXiong
authors.initials: W
authors.lastname: Lei
authors.forename: YuanHui
authors.initials: Y
authors.lastname: Li
authors.forename: SanYuan
authors.initials: S
authors.lastname: Tang
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging* / Q000293:injuries / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001863:Bone Screws; D005260:Female; D005593:Fracture Fixation, Internal / Q000379:methods*; D050723:Fractures, Bone / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000000981:diagnostic imaging* / Q000293:injuries / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult