A method and apparatus for motion correction of medical image data of a patient are provided. Medical image data is obtained in a tomographic image recording process by back-projection from a number of projection images. The position of a magnetic location sensor, which is arranged on a medical implant inserted into a patient is also determined as a function of time while the projection images are being recorded, by means of an electromagnetic location system and the position is taken into account in the back-projection of the projection images for motion correction purposes.