Simulation for Reduction of Transverse Acetabular Fractures in Sawbones Models

PURPOSE: The transversely oriented fracture lines are very difficult to reduce during operations, even after clear exposure of the fracture site, in acetabular fractures. The purpose of this study is to verify the quality of reduction between the different subtypes (transtectal, juxtatectal, and infratectal) of transverse fractures. This study also determined the proper type of clamps to use and the proper zone for achieving accurate reductions in Sawbones models. MATERIALS AND METHODS: Six fractures in 3 different subtypes of transverse fractures were artificially created. Ten different reduction clamps were applied for reduction of the fractures. Twelve holes around the fracture were drilled for the maintenance of the clamps. The fracture displacements were measured at the extra-articular area and the intra-articular joint portion. The pictures of the intra-articular fracture displacements were taken by a camera and these were uploaded and analyzed by the TraumaCad® computer program (Brainlab). RESULTS: The reduction quality was poor in order of transtectal, juxtatectal and infratectal. The intraarticular opening was more prominent in the transtectal subtype. The safe zone, when giving consideration of the neurovascular bundles, was a quadrilateral surface of the ilium. Drill holes are useful for maintenance of the reduction clamps. Reduction clamps with points (Weber clamp) were the best for maintenance and accurate reduction. Regarding the concerns of placement of clamps, the middle to posterior combination was the best. The upper hole among the posterior holes in the ilium was the most likely to well reduce the intra-articular opening. CONCLUSION: Transtectal was the more complicated subtype in the aspect of reduction quality. The Weber type reduction clamp was the best for reduction by centrally located holes in the quadrilateral surface and posteriorly located iliac holes in transverse acetabular fractures. The upper hole, among the posterior holes in the ilium, was the best for reduction of the fracture displacements in the intraarticular portion of acetabulum.

Biomechanical evaluation of transverse acetabular fracture fixation / 中华创伤骨科杂志

Objective To conduct a biomechanical evaluation of the four internal fixation methods to treat transverse acetabular fracture and find the b est one. Methods The transverse acetabular fracture models were created by osteo tomy in 12 pairs of embalmed cadaveric hip joints, and fixed with one of the fou r different methods: an anterior column plate (P/N), an anterior column plate w ith a posterior column screw (P+S), a posterior column plate with an anterior screw (S+P) and two posterior column plates (N/P?2). The biomechanical stabi lity was evaluated on longitudinal displacement, level displacement and stiffnes s measurements for fixed fracture fragments which were under 800 Newton vertical compression load. Results The longitudinal displacement in S+P was 3.99mm, in P+S 4.09mm, in N/P?2 5.07mm and in P/N 5.66mm; the level displacement in S+P was 0.015mm, in P+S 0.016mm, in N/P?2 0.022mm and in P/N 0.025mm; the average stiffness in S+P was 205.77N/mm, in P+S 207.52N/mm, in N/P?2 162.36N/mm and i n P/N 146.67N/mm. There were significant differences between the groups of S+P and P+S and the groups of N/P?2 and P/N (P