Presentation
Back pain.
Patient Data
Age: 35 years
Gender: Male
From the case:
Lumbosacral transitional vertebra
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On sagittal images an S1 vertebra is mimicking L5 (lumbarization of S1). If you compare the axial planes, there is a characteristic shape of lumbar facet joints on the L5/S1 level, and the S1/2 facets are smaller and flatter.
Case Discussion
Lumbasacral transitional vertebrae (LSTV) is one of the most common congenital anomalies of the lumbosacral region. It usually involves the fifth lumbar vertebra and can result in numerical abnormalities of vertebral segments. Lumbarization of first sacral vertebra is seen in 2% of cases.