[Improved radiological imaging of acetabular screw socket].

The improved radiological representation of the cementless acetabular screw-socket at two levels is of fundamental importance for the postoperative determination of position as well as for the judgement of an aseptic loosening. To improve the radiological representation two special radiographic techniques in the anterior-posterior as well as in the axial view have been examined on a human preparation of pelvis and have been scrutinized on a great number of clinical patients. The a.-p. radiography with twenty degrees cranio-caudal prone view in the sagittal plane and the axial radiography with forty-five degrees caudo-cranial prone view in the coronal plane shows the best and fewest overlayed representation of the screw-socket. The position of inclination and anteversion could have been directly determined out of these two radiographs. Malpositions of the screw-socket, especially with regard to the anteversion are easily identifiable due to the special axial radiographic technique. Overprojection of adjoining bone areas, which were possible should be considered at the judgment of the implant-bone-contact. Radiographic technical and positioning problems were not observed in patients. Out of these examinations the a.-p. radiography with twenty degrees cranio-caudal prone view in the sagittal plane and the axial radiography with forty-five degrees caudo-cranial prone view in the coronal plane could be recommended to the radiological diagnosis after implantations of hip prosthesis.