The English word for thoracic spine is Thoracic Spine, so in clinical work the industry usually uses a capital T plus a number to mark the vertebrae of the thoracic spine, which has a total of 12 vertebrae, referred to as T1-T12 from top to bottom. Thoracic spinal stenosis is most likely to occur in the part of the lower thoracic spine connected to the lumbar spine, called the thoracolumbar segment, specifically the 10th thoracic vertebra to the 2nd lumbar vertebra (T10-L2). ). The thoracic vertebrae together with the connected ribs and sternum form the thorax, which resembles a “cage”, making the stability of the thoracic vertebrae very good and the mobility of the intervertebral joints relatively small. However, below the 10th thoracic vertebra, there is no protection from the thoracic contour, and the lumbar vertebra, which is very mobile, is connected downward. Therefore, the thoracolumbar segment can be seen as a transition zone from a stable and immobile thoracic structure to a flexible and mobile lumbar structure. In addition, the thoracic spine protrudes posteriorly, while the lumbar spine protrudes forward, and is also a transitional region in the thoracolumbar segment. These anatomical features make the thoracolumbar segment the most susceptible to thoracic spinal stenosis, accounting for about 70% of cases. The second high incidence site is the upper thoracic spine (T1-T4). This segment is located in the transition area from the cervical to the thoracic spine and is also more prone to thoracic spinal stenosis. The mid-thoracic spine (T5-T8) is the most stable and has a low incidence of thoracic spinal stenosis.