Figure 1: Anteroposterior radiograph of lumbar spine.
Figure 2: Lateral view of spine.
A 16-year-old presents with mild lower back pain that has been present for several months. The patient reports no pain radiating down the legs or difficulty walking. He has no history of juvenile rheumatoid arthritis or a spine infection. His mom believes his pediatrician mentioned he had a spinal deformity years ago. Radiographs are ordered (Figures 1 and 2). On physical examination, the patient has mild lower back stiffness when he bends to touch his toes otherwise, he has no pain with rotation and extension of the back. His motor skills and sensations are intact in his lower extremities.
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The patient presents with a congenital vertebral synostosis (CVS) at L1-L2. A congenital lumbar synostosis is an uncommon condition caused by failure of lumbar spine segmentation resulting in inappropriate vertebral fusion. Congenital vertebral synostosis is generally found incidentally on imaging as the patient is often symptom free. Symptoms can arise if patients develop adjacent segment degeneration or lumbar stenosis.1,2
The amount of fusion can vary from partial or complete fusion of the vertebral endplates, facet joints, laminae, and spinous processes. Complete vs partial fusion depends on early or late failure of normal development. Complete vertebral fusion suggests early developmental failure.1,2
The majority of congenital fusions occur in the cervical spine, where they are often associated with Klippel-Feil syndrome.1,2 The patient in this case was advised to perform core strengthening at home and monitor his symptoms.
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor in chief of the Journal of Orthopedics for Physician Assistants.
1. Volk AM, Mathkour M, Iwanaga J, Dumont AS, Tubbs RS. A comprehensive review of congenital lumbar synostosis and associated findings. Cureus. 2021;13(10):e19013. doi:10.7759/cureus.19013
2. Paraskevas GK, Noussios G, Koutsouflianiotis KN, Iliou K. Congenital synostosis of cervical vertebrae: an osteological study and review of the literature. Cureus. 2019;11(10);e6015. doi:10.7759/cureus.6015