[Sciatic nerve: special topography and possibility of injuries in surgery of the hip joint (author's transl)].

The minimal distance between the dorsal acetabulum and the sciatic nerve can be 1.5 cm. This topographic situation is extremely important for surgery of the hip and dorsal pelvis (for e.g.: total hip prothesis, osteosynthesis of dorsal acetabulum-fractures). Various operative approaches to the hip joint lead to different intraoperative aspects including the danger of iatrogen sciatic nerve-lesions. In most cases the nerve cannot be seen but only be palpated during operation. If the stem of the sciatic nerve is injured intraoperatively, lesions can be found in the whole field of its innervation. For this reason specimen operations were performed in human cadavers using various approaches to the hip joint. We systematically investigated the topography of this region--layer by layer--cutting sections in horizontal and sagittal plains. Based on our findings the course of the sciatic nerve is described with special emphasis on the danger of lesions during surgery of the hip joint and dorsal pelvis.