Fig. 3

A typical case to regulate the PSA and anteversion angle to obtain ideal TAD. a-b, preoperative anteroposterior (a) and lateral (b) X-ray to diagnose intertaochanteric fractures; c-f, the adjustment of the guide pin. When position of neck guide pin is higher (the PSA is larger, c) and anteversion angle of nail is more than normal (d), we need to internally rotate the nail to make anteversion angle smaller (f) (at the same time, the PSA will become less in AP view, e) to get better TAD; g-h, postoperative anteroposterior (g) and lateral (h) X-ray to confirm the fracture reduction. Green line, nail position; red line, current position; yellow, ideal position