Sacral hiatus
Encyclopedia
The laminae
of the fifth sacral vertebra, and sometimes those of the fourth, fail to meet behind, and thus a sacral hiatus occurs in the posterior wall of the sacral canal
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Lamina of the vertebral arch
The laminæ are two broad plates, extending dorsally and medially from the pedicles, fusing to complete the roof of the vertebral arch.Their upper borders and the lower parts of their anterior surfaces are rough for the attachment of the ligamenta flava....
of the fifth sacral vertebra, and sometimes those of the fourth, fail to meet behind, and thus a sacral hiatus occurs in the posterior wall of the sacral canal
Sacral canal
The vertebral canal runs throughout the greater part of the sacral bone; above, it is triangular in form; below, its posterior wall is incomplete, from the non-development of the laminæ and spinous processes....
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