In image-based finite element analysis, partial volume effects are a known byproduct of model creation. In this study, we developed and validated a materialassignment based approach to mitigate partial volume effects in N = 20 models of intact ovine tibiae with three popular element types (10-node tetrahedral, 8-node hexahedral, and 20-node hexahedral). Without partial volume management, the models over-predicted the torsional rigidity compared to physical biomechanical tests. To address this problem, a dual-zone material model was implemented to treat elements that overlap low-density surface voxels as soft tissue rather than bone. After optimization, the dual-zone models produced high absolute agreement with physical tests.