Structure
The posterior sacroiliac ligament consists of short and long heads that attach to the intermediate and lateral sacral crests and extend laterally to the iliac crest. They are superficial to the interosseous sacroiliac ligament and are continuous with the sacrotuberous ligament, laterally, and with the thoracolumbar fascia, medially. The short heads consist of horizontal fibers while the long head is made up of oblique fibers.
Related parts of the anatomy
Function
The posterior sacroiliac ligament provides pelvic stability by limiting the displacement of the ilium from the sacrum.
