The use of a virtual three-dimensional model to evaluate the intraosseous space available for percutaneous screw fixation of acetabular fractures

Abstract

We created virtual three-dimensional reconstruction models from computed tomography scans obtained from patients with acetabular fractures. Virtual cylindrical implants were placed intraosseously in the anterior column, the posterior column and across the dome of the acetabulum. The maximum diameter which was entirely contained within the bone was determined for each position of the screw. In the same model, the cross-sectional diameters of the columns were measured and compared to the maximum diameter of the corresponding virtual implant. We found that the mean maximum diameter of virtual implant accommodated by the anterior columns was 6.4 mm and that the smallest diameter of the columns was larger than the maximum diameter of the equivalent virtual implant. This study suggests that the size of the screw used for percutaneous fixation of acetabular fractures should not be based solely on the measurement of cross-sectional diameter and that virtual three-dimensional reconstructions might be useful in pre-operative planning.

Sex-specific Differences of the Infraacetabular Corridor: A Biomorphometric CT-based Analysis on a Database of 523 Pelves

“…Significant differences of both techniques were reported by Attias et al for the anterior column corridor [1].…”

“…Small sample sizes in previous studies limit the statistical analysis of periacetabular corridor parameters and their correlation with several anthropomorphic parameters [1,5,8,30,31,37]. An automatic registration and analyzing algorithm is one strength of this study facilitating large data acquisition of 523 pelves.…”

“…Therefore, CT data sets of 523 healthy pelves were evaluated to answer the following study questions: (1) What proportion of healthy pelvis specimens have an infraacetabular corridor that is 5 mm or larger in diameter? (2) Does a universal corridor axis and specific screw entry point exist?…”

Computer-assisted virtual preoperative planning in orthopedic surgery for acetabular fractures based on actual computed tomography data

“…[21,22] In pelvic-acetabular surgeries, VIRTOPS could be used in minimally invasive techniques to calculate the trajectory and size of the screws, and can also be used for transcolumn screws. [20,23,24] When we used Mimics software to simulate a severely injured pelvis model, the result was more comprehensive and simplified the operation by simulating each step of the procedure. Because this required some knowledge of computer in addition to medical knowledge, the segmentation process of our model was carried out by the surgeons who had studied this software system.…”

A retrospective analysis of percutaneous SI joint fixation in unstable pelvic fractures: Our experience in armed forces

“…[12][13][14] Relative contraindication to this technique would include cases of sacral dysplasia, which would narrow the safe zone for screw placement. Open fixation is warranted in cases of poor intraoperative visualisation due to various reasons including inadequate bowel preparation.…”