Sacrum with five pairs of sacral foramina

Sacrum is wedge shaped bone between two iliac bones forming posterior wall of pelvis. Normally, sacrum is generated by fusion of five sacral vertebrae constituting four pairs of sacral foramina [1]. 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. Similarly at the caudal end, first coccygeal vertebra when fuses with the apex of sacrum, this process is known as sacralization of coccygeal vertebra. Both processes described above may generate additional fifth pair of sacral foramina [2]. The author came across a sacrum with five pairs of sacral foramina due to fusion of coccyx to the apex of sacrum. Case is reported for the variation in the anatomy of sacrum and its clinical implications among Indian population as it is less known variant.