The so-called cervical-lumbar syndrome refers to the stenosis of the cervical and lumbar spinal canals at the same time, and the compression of the nerves in the spinal canal and clinical symptoms at the same time or successively. Its incidence rate in patients with cervical spondylosis and cervical spinal stenosis is about 20%. The spinal canals of patients with cervical spinal stenosis and spinal cervical spondylotic myelopathy (with symptoms of spinal cord compression as the main symptom) often show developmental stenosis. In cases where the ratio of the vertebral body to the sagittal diameter of the spinal canal is less than 1:0.75, the absolute value of the sagittal diameter of the spinal canal is mostly below 12mm, and there are even cases with a sagittal diameter of less than 10mm, but cases below 6mm are very rare.