Cervical ribs as a caution for spine surgeons in thoracic spinal surgery

Abstract

Cervical ribs are well-described anomalous additional ribs arising from the seventh cervical vertebrae, but they can be a potential cause for wrong-level surgery. We report a case of a 71-year-old female with bilateral lower limb weakness and numbness due to spinal stenosis from T8 to T11 correlated on magnetic resonance imaging (MRI). However, computed tomography (CT) of thoracic spine showed ossification of the yellow ligament (OYL) one level distal at T9-T12. The whole spine CT revealed the presence of cervical ribs, and the initial discrepancy was caused by counting thoracic spinal levels according to the rib heads. Intraoperative decompression confirmed the dura had merged with OYL at T8–T11. The patient made a partial neurological recovery and could walk independently at 6-month follow-up. This case serves as a reminder for spine surgeons surgical implications of cervical ribs when operating on the thoracic spine, and the authors suggest additional radiological examinations to include the cervical spine to minimize the chances of wrong-level surgery.