A memory device stores instructions, which, when executed by a controller, cause the controller to perform tasks. The tasks include obtaining a three-dimensional (3D) model of a patient's pelvis, identifying two landmarks of the 3D model of the patient's pelvis, defining a coronal radiographic plane of the patient, and determining a mediolateral axis of the 3D axis based on the two landmarks. The tasks also include planning the surgical placement of the acetabular cup into the acetabulum by positioning a virtual model of the acetabular cup relative to the 3D model and determining a planned version and a planned inclination based on the virtual model of the acetabular cup, the mediolateral axis and the coronal radiographic plane.