Anatomy
Bulge forward where top (ie base) of wedge-shaped sacrum, where it joins with bottom (ie L5) of lumbar spine.
Along with ileopectineal line, comprises the pelvic brim, edge of pelvic inlet (above, abdominal cavity; below, pelvic cavity). Sacrum tilts forward, presenting a sacrovertebral angle with lumbar spine; more prominent in female.
Vignette
Sacrum (Latin); sacred. Sacred bone, because of its position near reproductive organs.
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