Posterior sacral foramina
Encyclopedia
Lateral to the articular processes of the sacrum
are the four posterior sacral foramina (or dorsal sacral foramina); they are smaller in size and less regular in form than the anterior, and transmit the posterior divisions of the sacral nerves
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Sacrum
In vertebrate anatomy 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...
are the four posterior sacral foramina (or dorsal sacral foramina); they are smaller in size and less regular in form than the anterior, and transmit the posterior divisions of the sacral nerves
Sacral nerves
The five sacral nerves emerge from the sacrum. Although the vertebral components of the sacrum are fused into a single bone, the sacral vertebrae are still used to number the sacral nerves....
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