Sensory, muscular, and neurological abnormalities of the lower extremities often occur in thoracic spinal stenosis, and the clinical manifestations of the disease are mainly a series of syndromes of blood supply circulation to the thoracic spinal cord, sensory, muscular, and neurological abnormalities of the lower extremities caused by incomplete compression of the thoracic medulla. Thoracic spinal stenosis is a disease in which the thoracic spinal cord and nerve roots are compressed due to congenital or acquired degenerative factors, resulting in corresponding clinical symptoms and signs. The thoracic segment of the spinal cord has impaired blood supply and circulation, sensory and motor conduction caused by the compressor. There are many mechanisms that cause thoracic spinal stenosis, including congenital: spinal canal hypoplasia and shortened pedicles; hereditary abnormalities of bone metabolism such as Paget’s disease; and Vit-D resistant bone disease. There are also acquired ones: nephrotic abnormalities of bone metabolism, fluorosis. The most common clinical condition is due to strain factors. Examination items: 1. X-ray examination of the thoracic spine X-ray plain film may show degenerative signs of varying degrees, the extent of which varies in size. Sometimes the posterior joint space and the vertebral plate space is blurred and the density is increased. Among them, the lateral film can be found on the hypertrophic protrusion into the spinal canal, which is an important basis for the diagnosis of this disease. 2, CT examination CT examination can clearly show the degree of thoracic spinal canal stenosis and the changes of the walls of the spinal canal. Posterior wall hyperplasia, ossification of the posterior longitudinal ligament, shortening of the vertebral arch, thickening of the vertebral plate, thickening and ossification of the ligamentum flavum, etc. can make the sagittal diameter of the spinal canal smaller; thickening and coalescence of the vertebral arch makes the transverse diameter shorter; hyperplasia of the posterior articular eminence and thickening and ossification of the joint capsule make the spinal canal triangular or trefoil-shaped. 3, MRI examination MRI can not only assess the changes in the spinal cord after compression, but also exclude other intramedullary and extramedullary lesions caused by compression, such as tumors, inflammation, etc.