Lumbosacral Transitional Vertebrae- An Osteological Study In Dry Human Sacra Of North Indian Origin With Its Clinical And Forensic Implications

Context: Lumbosacral transitional vertebrae (LSTV) are congenital anomalies that occur due to defect in normalsegmentation of the lumbosacral spine during development. This may be either in the form of assimilation offifth lumbar vertebra with the sacrum (sacralisation), or transition of the first piece of sacral vertebra into thelumbar configuration (lumbarisation).Aims and Objectives: Although presence of LSTV is common in general population but knowledge about its exactclinical implications is still lacking. The primary aim of the present study was to determine the rate of incidenceof transitional vertebra and their sex difference (if present) in dried human sacra. Secondary aim was to studythese transitional vertebra in detail and correlate these findings clinically.Materials and Methods: A total of fifty unbroken adult sacra were examined (male to female ratio of 3:2). Thepresence or absence of a lumbar transitional vertebra was noted and classified as incomplete or complete. Thesacral indices (SI) of all sacra were measured and values compared between typical and atypical sacra with LSTVas well as between male and female sacra.Results: Out of fifty sacra, six sacra (12%) showed presence of LSTV. Among them, four (8%) showed sacralisationof the fifth lumbar vertebra and two (4%) showed lumbarisation of first sacral vertebra. Among the four sacrashowing sacralisation, two showed incomplete fusion and two showed complete fusion of fifth lumber vertebrawith sacrum. LSTV was found to be more common in male than female. Sacralisation was seen only in male sacrawhile lumbarisation only in female sacra. The difference in the mean SI of typical sacra (97.76±4.08) and sacrawith LSTV (83.69±2.38 and 98.11±1.52 for sacralised and lumbarised sacra respectively) was found to bestatistically significant (p<0.05) and that between the male (94.55±5.70) and female (100.14±3.42) sacra wasfound to be highly significant (p<0.01).Conclusion: Presence of LSTV has many clinical and forensic implications and its knowledge is important fororthopaedic surgeons, neurosurgeons, forensic experts and also to radiologists.