The sacrum is a large, triangular bone at the base of the spine and at the upper and back part of the pelvic cavity, where it is inserted like a wedge between the two hip bones. Its upper part connects with the last lumbar vertebra, and bottom part with the coccyx (tailbone).
The sacrum is noticeably sexually dimorphic (differently-shaped in males and females). In the female the sacrum is shorter and wider than in the male; the lower half forms a greater angle with the upper; the upper half is nearly straight, the lower half presenting the greatest amount of curvature. The bone is also directed more obliquely backward; this increases the size of the pelvic cavity and renders the sacrovertebral angle more prominent. In the male, the curvature is more evenly distributed over the whole length of the bone, and is altogether greater than in the female.
|This page uses content from Sacrum. The list of authors can be seen in the . As with Spanking Art, the text of Wikipedia is available under a copyleft license, the Creative Commons Attribution Sharealike license.. The original article was at|