Sacrospinous ligament

The sacrospinous ligament (Latin lig. sacrospinosum, English Sacroiliac ligament), also known as the sacrospinous or sacrospinous ligament, is a fibrous interosseous formation of the sacral spine and the iliac wing fused to it.

The function of the ligament is to attach the sacral region to the transverse and spinous processes of the lumbar spine. The ligamentous complex provides stability to the sacrum and provides attachment to the gluteal muscle and perineum.

The ligament has three bundles: two anterior and one posterior. The anterior bundle runs from the fossa of the sacral crest behind the tuberosity to the outer protrusion of the transverse process of the fifth lumbar vertebra, the posterior bundle runs from the sacrum along the pelvic edge of the sacroiliac joint to the wall of the acetabulum. The branches of the lateral branches come from the transverse processes of the sacral vertebrae