A study of sacrum with five pairs of sacral foramina in western India.

Background: The sacrum is a large, triangular fused five sacral vertebrae and forms the postero-superior wall of the bony pelvis. Numerous anatomical variations of the sacrum have been reported including complete bilateral sacralization of the fifth lumbar vertebra or complete bilateral sacralization of first coccygeal vertebra in different race generates sacrum with five pairs of sacral foramina. There has never been reported among Gujarati population in Western India. These variations may be found in the living during radiological investigations for pain and neurological symptoms of patients or may be found during post mortem examination or during dissection of human body and osteology class for undergraduate students. Aims & Objective: The study was designed to know the prevalence of sacrum with five pairs of sacral foramina among Gujarati population in Western India as there is paucity of available literature. Considering the variation, we conduct this study as a prelude to any type of experimental work in biomechanics, for diagnostic and therapeutic purposes in low back pain, sciatica, coccydynia, spinal surgery and for interventional procedures like spinal anaesthesia and lumbar puncture. Material and Methods: Observational study was carried out on 302 dry human sacra from Department of Anatomy, B.J. Medical college Ahmedabad, Government Dental college Ahmedabad, Medical college Vadodara and Government Medical College, Surat in Gujarat. Morphological study was done on the sacrum. The sacra consisting of six vertebral segments were selected. The specimens were then carefully examined and recorded. Results: 302 dry human sacra were studied. Sacra with five pairs of sacral foramina were recorded. We founded 51 specimens of sacrum with five pairs of sacral foramina representing Bilateral complete sacralization of fifth lumbar vertebra (24 sacra) and bilateral complete sacralization of first coccygeal vertebra (27 sacra). Conclusion: The prevalence of a sacrum with five pairs of sacral foramina varies in general population is not reported separately. The present study shows that the incidence of sacrum with five pairs of sacral foramina among Gujarati population in Western India is 16.9%. Prevalence of sacrum with five pairs of sacral foramina is 7.9% and 8.9% due to sacralization of fifth lumbar vertebra and sacralization of first coccygeal vertebra, respectively. The knowledge of this anatomical variation is of paramount importance to spinal surgeons, obstetricians, radiologists, forensic experts, morphologists and clinical anatomists.