Cervical spinal cord injury is a rare but serious complication after general anesthesia. The risk factors include traumatic cervical injury, cervical spine instability, and difficult airway management. It has also occurred in the absence of cervical instability. Here we report a patient who had a history of intermittent neck pain without numbness. Preoperative radiologic examinations showed degenerative changes in the cervical spine. She developed progressive tingling and numbness in her limbs after thyroidectomy under general anesthesia. Magnetic resonance imaging showed a cervical disc protruding into the canal at C5-C6, which was considered to be induced by surgical positioning. She recovered after anterior cervical decompression and internal fixation surgery.