Cervical congenital spondylolytic spondylolisthesis associated with duplication of the vertebral artery: case report.

BACKGROUND CONTEXT: Cervical bilateral congenital spondylolysis with spondylolisthesis is an abnormality both of congenital and mechanical origin, characterized by its primary feature, cervical bilateral spondylolysis. We are unaware of any reports describing cervical congenital spondylolytic spondylolisthesis associated with duplication of the vertebral artery. PURPOSE: To report the case of a patient affected with cervical bilateral congenital spondylolysis with spondylolisthesis associated with duplication of the vertebral artery. STUDY DESIGN: A unique case report from a university hospital and a literature review. PATIENT SAMPLE: An 18-year-old man who arrived at the emergency department complaining of neck pain starting from a car accident 5 days ago. METHODS: Neurologic examination and images taken by ordinary radiographs, magnetic resonance imaging (MRI) scans, ordinary computed tomography (CT) scans, and CT angiograms with three-dimensional (3D) reconstruction. RESULTS: Neurologic examination did not find evidence of strength deficit in upper extremities. Ordinary radiographs of the cervical spine showed spondylolisthesis of C6 and C7 and a cortical cleft between the superior and inferior articular facets of the C6 vertebra and spina bifida of the C6 and C2 vertebrae and an abnormal appearance of the remnant spinous processes of the cervical vertebrae. Magnetic resonance imaging confirmed the abnormalities that had been noted on the radiographs. Computed tomography scans of the cervical spine showed congenital spondylolytic spondylolisthesis and spina bifida of the C6 vertebra and duplication of the vertebral artery. They also showed double origins of the vertebral artery depicted by 3D angiographic reconstruction. Conservative treatment of wearing a cervical collar and receiving muscle relaxants and anti-inflammatory drugs was effective. With the pain completely subsided, the patient was discharged 5 days after arriving at the emergency department. CONCLUSIONS: Vascular abnormalities should be suspected and investigated in cases of congenital spondylolysis or spondylolytic spondylolisthesis. We strongly suggest performing angio-CT or angio-MRI and 3D reconstruction in these cases. Awareness of the presence of a duplicated vertebral artery and the course of its limbs could significantly help planning in cases proceeding to surgery.