The "sacred bone" is the sacrum, a bone located at the base of the spine. The term "sacred bone" or os sacrum comes from Latin. Eighteenth-century anatomists coined the term.
In more detail:
The sacrum is a large, triangular bone formed by the fusion of five sacral vertebrae (S1-S5). It's located at the base of the vertebral column, where it connects to the hip bones (ilium) forming the sacroiliac joints. This connection is crucial for weight-bearing and stability of the pelvis.
Functions of the Sacrum:
- Connects the spine to the lower body: It acts as a bridge between the vertebral column and the pelvis.
- Supports the spine: It provides a stable base for the upper body.
- Protects pelvic organs: It contributes to the posterior wall of the pelvic cavity, offering protection to the organs located within.
- Provides attachment points for muscles and ligaments: Various muscles and ligaments attach to the sacrum, contributing to its stability and movement of the lower body.
Why it's called "sacred": The exact origin of why os sacrum translates to "sacred bone" is debated. Some theories suggest:
- Resurrection Beliefs: Ancient cultures believed that this bone would be the last to decompose, thus making it essential for resurrection.
- Sacrificial Use: Some speculate that the sacrum may have been used in sacrificial rituals.
- Location: Its location near the reproductive organs might have contributed to its sacred status.