RESUMEN
Objective To get a controllable acetabulum component inclination angle during the total hip arthroplasty(THA) with the lateral position,a new method using a self-made instrument was introduced.Methods Totally 80 consecutive patients undergoing THA at the lateral position were enrolled.Forty acetabular components were assembled using a new method with a self-made instrument referring to the 42 degrees' angle drawn on the wall(group A),while another 40 acetabular cups were implanted free-handedly(group B).The postoperative inclination angle was evaluated on the anterior-posterior pelvic radiographs.Results The average inclination angle was 43.3° ± 3.7°(34.7°～49.1°) in group A and 40.3 ± 4.5o(32.8°～50.7°) in group B.Moreover,40/40 of group A and 38/40 of group B were in the Lewinnek's inclination safe zone(P＞0.05),without significant differences between the two groups.Conclusion It is practical and reliable to decide the acetabular component orientation using the lateral position instrument and reference angle on the wall.