[Possibilities of geometric X-ray examination of the pelvis for partial pelvis replacement].

Patients with tumors of the pelvis, which cannot be treated by chemotherapy or radiation, must undergo hemipelvectomy. The postoperative prosthetic treatment was difficult und not always sufficient. So, a complete internal hemipelvectomy was done by replacement of an artificial part of half pelvis. Before the operation it was necessary to know the measurements of the pelvis exactly. This was done by taking X-ray pictures in anterior--posterior, lateral and axial direction which brought out the relevant diameters for the construction of the artificial pelvis. By using the Computer-Tomography we could get exact slices of the pelvis in the transversal plane. The slices were centrally positioned, then the model was covered with modelling-mass. The result was an exact positive feature of the pelvis which must be replaced.