Does 2.5 cm of Symphyseal Widening Differentiate APC I from APC II Pelvic Ring Injuries

The position of the hemipelvis was recorded with a three dimensional motion capture system and video. We recorded the displacement of the symphysis pubis, the displacement of the anterior aspect of the sacroiliac joint, and the applied torque to determine the symphysis pubis distance that corresponded with failure of the anterior sacroiliac ligaments. CONCLUSIONS Significant morphological variation is seen in anterior sacroiliac tolerances. Our data support that anterior sacroiliac ligament disruption is likely for displacement >4.5 cm and may or may not be disrupted for values between 1.0 and 4.5 cm. Additionally, our study suggests that the sacrospinous and sacrotuberous ligaments might not rupture prior to the anterior sacroiliac ligament.