Abstract: ［Abstract］ Objective〖HTSS〗〓To analyze the accuracy of auxiliary positioner of proximal femoral nail antirotation（PFNA）in the clinical application.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓Selected 40 patients with intertrochanteric fracture of the femur, according to the doubleblind method, were divided into control group and observation group. The first 20 patients in the control group were received conventional surgery by PFNA. The rest 20 patients in the observation group were received PFNA surgery with screwblade implanted auxiliary positioner. The number of implantation, the duration of operation and the number of Carm Xray exposure were recorded. The accuracy of the placement was evaluated by measuring the angle between the axis of the screw blade and the central axis of the femoral head(deflection angle).
〖HTH〗〖WTHZ〗Results〖HTSS〗〓The operation time, Xray exposure time, the number of screw inserts and the deflection angle of the observation group were less than those of the control group. The difference was statistically significant(P＜0.05).
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓The proximal femoral screw counter screw blade assisted positioner allows for faster and more accurate placement of the screw blade at once. It can obviously reduce the exposure times of Carm and effectively reduce the radiation damage of related personnel.

Key words: femoral fractures, fracture fixation, internal, implanted auxiliary positioner