Further development of our finite element pelvic model to compare fixation methods for pelvic fractures
Gergely Sztrinkai1, Tamás Bodzay1, Sándor Pajor1, Péter Erdös2, Zsolt Vendégh1, Zoltán Jónás3, Károly Váradi2
1Trauma Centre, Péterfy Hospital, Budapest, Hungary
2Faculty of Mechanical Engineering, Institute of Machine Design, University of Technology and Economics, Budapest, Hungary
3Department of Orthopaedic Surgery, University of Debrecen, Medical and Health Centre, Debrecen, Hungary
Keywords: Finite element analysis; fracture fixation; pelvic bone.
Objectives: In this study, we aimed to create a realistic model which is suitable for computerized simulation of any kind of fractures and provides reliable results.
Patients and methods: We used a plastic pelvic model to construct advanced specimens. The data were retrieved from the computed tomography scans of a healthy pelvis. A geometrically exact model by the means of three-dimensional scanning of the plastic pelvis was obtained. The material properties of the bony parts based on the data retrieved from the computed tomography scans were modified. The pelvis was divided into distinct segments and the proportion of the cortical and cancellous bone substance in each segment were determined to make the material properties accurate. In the validation of the pelvic model, a type C pelvic injury was simulated and the fracture of the sacrum and the symphyseolysis were stabilized with plates. These data were compared with those of previously performed cadaver experiments.
Results: Based on the simulation performed on the new model, the shift values between the fragments of the broken sacrum approximated the reported values of our cadaver experiments and also arising strains remained in the tolerable interval.
Conclusion: Our new finite element pelvic model represents the pelvis more accurately than the former one. As the validation of the model was successful, it is suitable for computerized simulation of any kind of fractures offering reliable results.