Limbus vertebra is a bony fragment that usually occurs at the anterosuperior margin of the lumbar vertebrae. The inferior and posterior margins are less commonly affected. It results from an old injury in the immature skeleton, resulting in herniation of the nucleus pulposus through the ring apophysis before fusion, separating a small segment from the vertebral rim.

Anterior limbus vertebra is usually asymptomatic. It is an incidental finding and typically not the cause of the pain. Thus, it needs no treatment. Limbus vertebra could be mistaken for a fracture, discitis, Schmorl’s node, or tumor.  This is most likely to occur when a patient presents with back pain, especially after trauma.