1. A method for determining the three-dimensional movement of an object positioned on a means for support between a means for providing a radiation source and a means for receiving an image in an imaging apparatus comprising: placing a plurality of radio-opaque markers on a body of the object, the markers constituting a fixed reference frame; taking at least one first radiographic image of the object for a first determined fixed position of the imaging apparatus in the reference frame of the markers; taking at least one second radiographic image of the object for a second determined fixed position of the imaging apparatus in the reference frame of the markers; and determining a matrix of the three-dimensional movement of the object with respect to the means for providing a radiation source of the imaging apparatus on the basis of the two-dimensional movements of the markers in the radiographic images, the means for providing a radiation source constituting a fixed reference frame.