With a growing elderly population, osteoporotic pelvic fractures have been an increasingly common worldwide problem. Due to the complexity of the human pelvis, difficulties exist in the diagnosis of subtle fractures and complications may arise from standard treatments. Guidelines for approaching pelvic fracture have been established, but the uniqueness and complexity of the pelvis leaves much to professional discretion. This thesis showed how a biomechanical study provides more objective insights in dealing with the pelvic fractures.
A three-dimensional digital image correlation (3D-DIC) was used for its ability to extract mechanical measurements across a sizeable area of the contoured pelvic surface. From a preliminary study, a procedure was established to effectively conduct an optimized experiment with this technique and to quantify the uncertainty of its measurements. An existing experimental setup was redesigned and reconfigured for testing and measuring with an integrated DIC system. From initial experimentation and validation, it was shown that crack behavior can be accurately characterized using the ability of the test setup to measure crack edge openings as small as 0.03 mm with less than 10% uncertainty.
When testing on an intact pelvis, the measurements were very repeatable, observed to be about 10% for strain measurements. After testing a fractured pelvis and comparing the results to the intact pelvis, it could be seen how a crack causes shifts in the tension and compression profiles experienced by a normal pelvis. It was also shown that the test setup could observe crack behavior on a microscopic scale while observing a significant area of the pelvis. Crack edge opening measurements with less than 10% uncertainty were then used to characterize the stability of the fractured specimen. The designed setup was proven to be an effective tool for analyzing the mechanics and stability of a fractured pelvis.