Fig. 7

Personalized position map of femoral neck guide pin. a, the relationship between neck shaft angle and anteversion angle of the guide pin when axial rotation angle of main intramedullary nail changed; b, application of personalized distribution map of femoral neck guide pin. The coordinates of the black line was corresponding to the ideal location of femoral neck guide line in preoperative planning. PSA of guide pin is 135.7°, while anteversion of guide pin is 24°. The coordinates of the red line was corresponding to the first position of femoral neck guide line in operation; based on the PSA and anteversion angle of guide pin measured in the operation, the corresponding positions in the figure are found; the abscissa and the rotation angle of the main intramedullary nail are found; compared with the abscissa of red and black line, the method to adjust the guide pin location can be obtained