This study was performed to evaluate the efficacies and the reliabilities of methods used to measure acetabular anteversion in plain radiographs.

Three orthopedic surgeons measured prosthetic acetabular anteversions in three plain AP and three translateral radiographs of ten patients who underwent total hip arthroplasty. In each film, we measured anteversions three times using three methods in AP and a direct method in translateral radiographs. Data were collected and analyzed statistically with CT axial and planar anteversion measured by a radiologist.

All methods with plain AP film showed very low inter and intraobserver variances and correlated well with CT planar and axial anteversions. Although the data obtained from translateral radiographs were showed low variances, they did not correlate with those of the other methods.

Simple estimation alone or mathematical methods can be reliably and reproducibly used to assess planar anteversion in a clinical setting. Data from translateral radiographs were unreliable and did not correlated well with the other methods, and they are not recommended for clinical use.