[The postoperative control CT after a fracture of the acetabulum. A useful quality control measure or an unnecessary exposure to radiation?].

Fractures of the acetabulum are severe injuries of the hip joint. Exact preoperative management is necessary to make possible an anatomical reconstruction. Postoperative quality control is done best with computed tomography. Is the higher radiation exposure caused by this routine examination justified?During the 5 years from 1995 to 1999, a total of 154 patients with fractures of the acetabulum were examined postoperatively at our clinic using CT to control reconstruction, implant position and the remaining free fragments in the joint. Thirteen of these patients (8.4%) had to be re-operated after postoperative CT control. The causes of the re-operation were four cases of an intra-articular implant position, three of free fragments remaining in the joint, and in 6 patients showed inadequate reconstruction. The mean radiation exposure was 25 mGy per patient. The low mean age of the patients and the long lasting consequences of a probably unrecognised complication, justify routine, postoperative CT control, even though the radiation exposure is about 10 mGy higher than the conventional radiological diagnosis. The use of CT diagnosis as a routine postoperative measure is an appropriate control procedure that allows an objective assessment of the quality of the result for the patient as well as for the surgeon.