The causes of cold pain in the back and lower limbs include blood circulation disorders, intercostal nerve injury, bone and joint diseases, etc. 1. Blood circulation disorder: due to prolonged sitting or standing, being cold, or living in a cold environment for a long time, the blood in the lower back and legs is stagnant, the circulation is not smooth, and the heat can not be transported to the whole body, thus causing the symptoms of cold pain in the back and lower limbs. 2. Intercostal nerve injury: If the patient suffers from intercostal nerve injury due to trauma or other reasons, it may also cause the patient to suffer from cold pain in the back and lower limbs. 3. Bone and joint diseases: mainly caused by degenerative diseases, such as patellar synovitis, lumbar degenerative disease (spinal stenosis), etc., patients will appear back and lower extremity cold pain symptoms, usually accompanied by joint stiffness and other symptoms. Some elderly patients even have to wear cotton knee pads for their knees in the summer. In addition to the above diseases, lumbar disc herniation and other diseases can also cause the above symptoms. If the above situation occurs, it is recommended to go to the hospital for examination, identify the cause of the disease, and carry out regular treatment under the guidance of the doctor.