A small percentage of the population possesses an additional vertebral element, most commonly at the lumbosacral junction. This anatomical variation, sometimes referred to as a transitional vertebra, represents a congenital anomaly where the last lumbar vertebra partially or fully fuses with the sacrum, or conversely, the first sacral vertebra takes on lumbar characteristics. This can result in six lumbar vertebrae instead of the typical five.
The presence of this variant can be clinically significant, potentially contributing to lower back pain and altered biomechanics. Historically, its identification has relied on radiographic imaging, and its association with specific musculoskeletal conditions has been a subject of ongoing research. Understanding its prevalence and potential implications is crucial for accurate diagnosis and treatment planning in individuals presenting with lower back complaints.
