System for pose estimation of three-dimensional bone models in surgical planning a joint replacement procedure

A system for processing patient data associated with a joint of a patient. The system comprising a computing device executing instructions to generate a 3D patient bone model of the joint in a non-weighted pose. The instructions rearrange 3D first and second bone models in order to mimic a weighted pose of the joint of the patient from a 2D image of the joint of the patient in a weighted pose by performing the steps of: generating a plurality of 2D projections of poses of the 3D patient bone model; comparing the plurality of 2D projections to contour lines of the first bone and the second bone in the 2D image; identifying particular 2D projections that best-fit a shape and size of the contour lines; and arranging the 3D first and second bone models relative to each other according to orientations represented by the particular 2D projections that were identified.