Structure
The sacrospinous ligament connects the ischial spine to the lateral borders of the sacrum and coccyx. It is roughly triangular and helps to convert the greater and lesser sciatic notches into the greater and lesser sciatic foramina. Its anterior surface is continuous with the coccygeus muscle.
Function
The sacrospinous ligament confers stability to the pelvis by limiting the movement of the pelvis and the sacrum.
