Method for determining craniocaudal length change and mediolateral change femur offset, involves calculating spatial change of location coordinates and projecting spatial change of location coordinates to craniocaudal reference direction

摘要

The method involves defining a reference coordinate system using a surgical reference marking device (26,28). The surgical marking device is defined at the femur (12) for defining a primary characteristic point on the femur. The location coordinates of the primary and secondary characteristic points of the femur are determined in the reference coordinate system before and after implantation. The spatial changes of location coordinates of the primary and secondary characteristic points in the reference coordinate system due to the implantation are calculated. The change in length of the femur is determined by projecting the spatial change of the location coordinates of the primary characteristic point to the craniocaudal reference direction. The change of the offset of the femur is determined by projecting the spatial change of the location coordinates of the secondary characteristic point to the mediolateral reference direction. Independent claims are included for the following: (1) a device for determining craniocaudal length change and mediolateral change of the offset of a femur of a patient due to the implantation of an artificial hip joint; and (2) a computer program product with a computer readable medium for storing a computer program for determining craniocaudal length change and mediolateral change of the offset of a femur of a patient due to the implantation of an artificial hip joint.