Incidental diagnosis of limbus vertebra in a patient with sciatica

The limbus vertebra is formed due to anterior herniation of the nucleus pulposus between the ring apophysis and the adjacent vertebral body, resulting in the formation of a triangular, smooth bony fragment that ossifies separately. It is commonly located in the mid-lumbar spine, usually at the antero-superior margin of a single vertebral body. We present the case of a 31-year-old male who presented to the Emergency Department with complaints of sciatica after bending forwards. The plain radiograph of the lumbosacral spine was suspicious for a L5 chip fracture but was diagnosed to have limbus vertebra and discharged. Limbus vertebra is generally identified incidentally, and most patients with anterior limbus vertebra are asymptomatic. Some patients with posterior limbus vertebra can present with symptoms of nerve compression. It can be mistaken for vertebral fracture, infection, degenerative disease of the spine or tumour, resulting in further diagnostic evaluation. Most patients are management conservatively, while those patients with symptoms of nerve compression requiring total laminectomy. Emergency physicians should consider the limbus vertebra as a differential diagnosis in patients presenting with lumbar pain, particular in young patients.