Influence of Age and Sex on the Position of the Conus Medullaris and Tuffier's Line in Adults

Abstract

During spinal block, there seems to be a safety margin of 2-4 vertebral bodies and intervertebral spaces between the conus medullaris and Tuffier's line, which is consistent regardless of sex or presence of transitional vertebra. However, because the conus medullaris and Tuffier's line become closer with age and the clinical use of Tuffier's line requires palpation through subcutaneous fat, caution must be exercised regarding selection of the intervertebral space, especially in the aged and obese population.