Preoperative Fluoroscopic Imaging Reduces Variability of Acetabular Component Positioning

We evaluated the preoperative errors in the pelvic tilt of 249 hips before total hip arthroplasty using fluoroscopic imaging while the patients were in the lateral decubitus position. The mean absolute value errors of the pelvic tilt were 2.94° (SD, 2.92°), 2.49° (SD, 2.68°), and 5.92° (SD, 5.20°) in the coronal, transverse, and sagittal planes, respectively. Such preoperative errors in the pelvic tilt contribute to malpositioning of the acetabular component, as is frequently observed on postoperative radiographs. We reduced the incidence of malpositioning by correcting the errors in the pelvic tilt through repositioning of the operating table using fluoroscopic imaging before surgery. The new technique using fluoroscopic imaging described in this article can be performed within a short time without a navigation system.