The lumbar spinal canal includes the central spinal canal, which is mainly the part occupied by the dural sac, and the lateral spinal canal, which is the narrowest part of the nerve root canal. The size and width of the lumbar spinal canal is different for each person, just like the height of a person. Some people have smaller than normal spinal canal development, but people with lumbar spinal stenosis usually develop a condition based on developmental spinal stenosis combined with arthrogryposis, disc herniation, and ligamentous hypertrophy. Patients with lumbar spinal stenosis and lumbar disc herniation both have herniated discs on CT and MRI, but the herniated lumbar discs play different roles in the two conditions. Lumbar spinal stenosis is characterized by significant relief or disappearance of pain with bed rest, typical intermittent rupture (i.e., symptoms appear after walking a few hundred meters, can be relieved with a little squatting and rest, can continue walking again, and the same symptoms appear after walking a few hundred meters, and can be relieved after rest), and no symptoms with bicycling, in addition to the fact that there are often no obvious localization signs on neurological examination. Lumbar disc herniation is characterized by typical radicular symptoms, i.e. pain radiating from the hip to the calf, obvious neurological localization signs on physical examination, and a positive straight leg raise test.