Pelvic fractures are severe injuries that are associated with high rates of mortality and morbidity, especially in the elderly population. In severe cases of fracture, urgent surgical intervention may be required with the use of fixation plates to stabilize the fracture. The surgical planning process of these fractures is complicated and time consuming, which could potentially increase the risk on the patients. Therefore, this thesis aims to provide a method for virtually reconstructing fractured pelvises with the goal of easing the surgical planning process and improving surgical outcomes.

For unilaterally fractured pelvises, pelvic symmetry was examined first to conclude whether the contralateral side can be used as a template for rebuilding the fractured side. Pelvic bilateral symmetry was evaluated by studying intact pelvises and calculating the differences between the left and right sides with the use of 3D deviation analyses. Results showed that the pelvis exhibits remarkable left-right symmetry, confirming that the uninjured sides of fractured pelvises can serve as viable models in virtual pelvis reduction. A reconstruction technique is presented and assessed in this thesis. It is a semi-automatic method that can provide accurate virtual reconstructions with deviations within the clinically acceptable range for preventing osteoarthritis in the hip joints.

For bilaterally fractured pelvises, there is no intact model to serve as a template for the reconstruction procedure. Therefore, average pelvic shape models were developed to work as templates for the reconstruction. Separate average shape models were developed for male and female hemipelves to account for sex differences in pelvic shape. Statistical shape modeling was used to build these average shape models from a group of intact pelvises. Differences in shape between the average shape models and the respective intact pelvises from which they were developed is discussed in this thesis. The average shape models were then used as templates to reconstruct unilaterally fractured pelvises. The results were compared to the same pelvises that were reconstructed by using the opposite intact sides as templates, in order to evaluate the quality of the reduction. Finally, the method for reconstructing bilaterally fractured pelvises using the average shape template is presented.

Developing an accurate virtual reconstruction method for different types of pelvic fracture has the potential to lower the overwhelmingly high mortality and morbidity rates. Surgeons will be able to provide better treatments for these patients by offering quicker treatment proposals and easing the design process of the fixation plates for surgery. This can reduce the wait times for patients prior to surgery while preserving the quality of the planned reconstruction procedure.