The posterior sacrococcygeal ligament or dorsal sacrococcygeal ligament is a ligament which stretches from the sacrum to the coccyx and thus dorsally across the sacrococcygeal symphysis shared by these two bones. This ligament is divisible in two parts: A short deep part which unites the two bones, and a larger superficial portion which completes the lower back part of the sacral canal. On either side, two lateral sacrococcygeal ligaments run between the transverse processes of the coccyx and the inferior lateral angle of the sacrum. It is in relation, behind, with the gluteus maximus.