Sacrospinous ligament Sacrospinous ligament The sacrospinous ligament (small or anterior sacrosciatic ligament) is a thin, triangular ligament in the human pelvis. The base of the ligament is attached to the outer edge of the sacrum and coccyx, and the tip of the ligament attaches to the spine of the ischium, a bone in the human pelvis. Its fibres are intermingled with the sacrotuberous ligament. The sacrotuberous ligament passes behind the sacrospinous ligament. In its entire length it covers the equally triangular coccygeus muscle, to which its closely connected. The presence of the ligament in the greater sciatic notch creates an opening (foramen),
Squamous part of occipital bone The lower division of the cruciform eminence is prominent and is named the internal occipital crest; it bifurcates near the foramen magnum and gives attachment to the falx cerebelli. In the attached margin of this falx is the occipital sinus, which is sometimes duplicated. In the upper part of the internal occipital crest, a small depression is sometimes distinguishable; it is termed the vermian fossa since it is occupied by part of the vermis of the cerebellum. Transverse grooves, one on either side, extend from the internal occipital protuberance to the lateral angles of the bone; those grooves accommodate the