sacral vertebra


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sacral vertebra

one of the five segments of the vertebral column that fuse in the adult to form the sacrum. The ventral border of the first sacral vertebra projects into the pelvis. The bodies of the other sacral vertebrae are smaller than that of the first and are flattened and curved ventrally, forming the convex, anterior surface of the sacrum. The rudimentary spinous processes of the first several sacral vertebrae surmount the middle sacral crest, and the transverse processes of the sacral vertebrae form the lateral sacral crests. The sacral hiatus at the caudal end of the sacral canal develops from the incomplete growth of the spinous processes of the last two sacral vertebrae. The resultant widened aperture is used by anesthesiologists for the insertion of a needle to administer caudal analgesia. Compare cervical vertebra, coccygeal vertebra, lumbar vertebra, thoracic vertebra. See also sacrum, vertebra.

sacral vertebra

One of the five fused vertebrae forming the sacrum.
See: sacrum for illus
See also: vertebra

sacral vertebra

one of the thick strong vertebrae of the lower backbone, some of which are fused together and attached to the PELVIC GIRDLE to form the SACRUM, giving great strength to the hip region.
References in periodicals archive ?
The fifth pair of sacral foramina is generated either due to fusion of first coccygeal vertebra to apex of sacrum or fifth lumbar vertebra with first sacral vertebra.
FM- foramen magnum, C7- seventh cervical vertebra, T1- first thoracic vertebra, T13- thirteenth thoracic vertebra, L1- first lumbar vertebra, L2- second lumbar vertebra, L3- third lumbar vertebra, L5- fifth lumbar vertebra, L6- sixth lumbar vertebra, S1- first sacral vertebra, S2- second sacral vertebra, S3- third sacral vertebra, S4- fourth sacral vertebra.
Measurement of maximum length of sacrum was recorded by the distance from antero-superior margin of promontory to the middle of anteroinferior margin of the last sacral vertebra.
The prevalence rate of lumbarization of first sacral vertebra is 3.
Partial or complete fusion of fifth lumbar vertebrae with first sacral vertebra is called sacralisation.
Location of the apex of sacral hiatus in relation to level of sacral vertebra varied from S2 to S5 vertebra level.
At the cranial end of sacrum there is fifth lumbar vertebra, which when fused with the first sacral vertebra is known as sacralization of lumbar vertebra.