To evaluate the reference value of transverse acetabular ligament to the proper placement of the artificial cup during total hip arthroplasty.

There were 87 patients (174 hips) who met the inclusion and exclusion criteria from January 2017 to December 2018, including 49 males (98 hips) and 38 females (76 hips). The anatomical anteversion of the transverse acetabular ligament on three-dimensional reconstruction images of the pelvic were measured and the differences in gender, laterality as well as different ages were compared and the proportion of the safe-zone was calculated. The anatomical anteversion of the acetabulum was also measured and the differences in gender and laterality were compared. Independent-sample t-test or paired-sample t test were used to compare the differences of gender and side, and one-factor analysis of variance was used to analyze the difference between different ages.

The mean values of anatomical anteversion of acetabular was (22± 4)°, without significant difference in gender and laterality (t =-1.491, -1.518, both P >0.05). The mean values of anatomical anteversion of acetabular was (18±5)°, without statistically significant difference in gender and laterality (t =-0.319, -1.437, both P >0.05)). No statistically significant difference was found among different age groups (F =0.828, P>0.05). The proportion of the cups in the safe area was 98.85%.The values of anatomical anteversion of acetabular was smaller than the values of anatomical anteversion of acetabular with statistically significant difference(t=7.859, P<0.001).

In patients without acetabular dysplasia, transverse acetabular ligament can be used as a valuable intraoperative reference mark for the placement of the cup during the total hip arthroplasty surgery.