Biomechanical comparison of three different fixation techniques for anterior column posterior hemitransverse acetabular fractures using anterior intrapelvic approach

The aim of this study was to biomechanically compare three different fixation methods for the fixation of anterior column posterior hemitransverse type acetabular fracture (ACPHT). ACPHT fracture models were created on twenty-four foam cortical shell artificial hemipelvis models. Three fixation methods were assessed - Group 1: posterior column lag screws over a suprapectineal plate; Group 2: Posterior column lag screws over a suprapectineal plate and an infrapectineal plate; Group 3: A suprapectineal plate and a vertical infrapectineal plate. Stiffness and displacement amounts of fixation methods under dynamic and static axial loading conditions were measured. In the dynamic and static tests, Group 3 showed the less stable fixation compared to Group 2. There was no statistically significant difference between the stiffness values of the fixation groups. In the static tests, there was no statistically significant difference between Group 1 and 2, although less displacements were obtained in Group 2. A combination of posterior lag screws over a suprapectineal plate and an infrapectineal plate supporting the pelvic brim along both sides of the linea terminalis resulted in a better fixation construct than a suprapectineal plate accompanying with a vertical infrapectineal plate provide better stability with less fracture displacement.