Can the possibility of transverse iliosacral screw fixation for first sacral segment be predicted preoperatively? Results of a computational cadaveric study

BH and HDS1 could be used to predict the possibility of TIS screw fixation. If the BH exceeds 20.6 mm or HDS1 is less than 18.6 mm, TIS screw fixation for S1 should not be undertaken because of narrowed SZ.