LAUSR

OBJECTIVE The aim of this study was to determine safe paths for screw placement on the posterior column of the acetabulum. METHODS A total of 25 male hemipelvises were utilized in this study. These hemipelvises were sectioned, and formed cross-sections A, B, C, D, and E. The length of the screw and screw posterior column angle of the entry points at cross-sections B, C, and D were measured. RESULTS On the margin of the acetabulum, lateral middle 1/4 point, midpoint, medial middle 1/4 point, and medial margin of the posterior column of each cross-section, the safe entry angle of inclination is 39, 57, 74, 90, and 106°, respectively, and the length of the screw is 35.5 mm, 33 mm, 32 mm, 31 mm, and 74 mm, respectively. CONCLUSION On the lateral 1/4 region, lateral middle 1/4 region, medial middle 1/4 region, and medial 1/4 region of the posterior column, the screw posterior column angle is 40 ~ 60°, 60 ~ 75°, 75 ~ 90°, and 90°~parallel to the quadrilateral plate, respectively, and the length of the screw is 30 mm.