Sacrum apex is directed downward and presents an oval facet for articulation with the coccyx. The sacral canal as a continuation of the vertebral canal runs throughout the greater part of the sacrum. The sacral angle is the angle formed by the true conjugate with the two pieces of sacrum. Normally it is greater than 60 degrees. A sacral angle of lesser degree suggests funneling of the pelvis. The sacral promontory marks part of the border of the pelvic inlet, and comprises the iliopectineal line and the linea terminalis. The sacral promontory articulates with the last lumbar vertebra to form the
Composition of the human body are averages of different numbers reported by different references. The adult human body averages ~53% water. This varies substantially by age, sex, and adiposity. In a large sample of adults of all ages and both sexes, the figure for water fraction by weight was found to be 48 ±6% for females and 58 ±8% water for males. Water is ~11% hydrogen by mass but ~67% hydrogen by atomic percent, and these numbers along with the complementary % numbers for oxygen in water, are the largest contributors to overall mass and atomic composition figures. Because of water content, the human body