Morphological Variations of Sacrum in Adult Indian Population

Abstract

Introduction: The sacrum is considered as a highly variable bone. Several morphological variations have been documented which exhibit differences in the frequency of occurrence and morphological characteristics in various study populations. Variant anatomy of the sacrum may be associated with backache, enuresis, neurological anomalies of the lower limb and functional disorders of lower urinary tract. Purpose: The purpose of this study was to identify and describe morphological variations of sacrum in Indian population and enable comparison with different populations. Materials and Methods: The study was conducted on 108 dry adult human sacra and morphological characteristics and variations were noted. Results: Sacral skewness was observed in 7.4% sacra with right sided skewness being predominant. The presence of accessory auricular surface (AAS) was noted in 13% sacra which was at the level of S3 vertebra in most sacra. Spina bifida (SB) was observed in 11.1% sacra and it was most commonly located at S1 vertebral level. Furthermore, the lumbo-sacral transitional vertebra (TV) was documented in 10.2% sacra. Conclusions: Sacrum displays numerous variations in Indian population such as skewness, AAS, SB and TV. Thorough knowledge of morphological characteristics and variations of sacrum is vital and should be contemplated during diagnosis and treatment of sacrum-related diseases. KEY WORDS: Accessory auricular surface, Spina bifida, Transitional vertebra, Sacral skewness, Variations.