Cold legs are a subjective sensation and there are more possible causes, which are more common in elderly patients. In addition to environmental, physical, and other functional factors, general possible conditions include: poor vascularity and obstructed circulation in the lower extremities, and long-term pressure on the nerves in the lower extremities caused by lumbar spine diseases can trigger coldness and abnormal sensation in the lower extremities. Older patients may be many combined with hypertension, diabetes, hyperlipidemia, hyperuricemia and other metabolic diseases, bone and joint degeneration and other factors will be more likely to occur. Chinese medicine theory that older people often viscera deficiency, kidney Yang deficiency leads to a decrease in warming function, will also cause cold legs. 1, there are problems with the circulation of the lower limbs. Arterial plaque, stenosis, varicose veins, reflux, thrombosis and other causes of lower extremity blood supply disorders, poor circulation or obstruction can trigger cold or swelling of the lower extremities. In addition, patients with perennial diabetes and poorly controlled hypertension have poor elasticity of the vascular walls of the lower extremities, damage to the lining of the walls, and poor blood return, which can also easily cause coldness and swelling of the lower extremities. It may be accompanied by varicose veins, dry skin, thinning hair, dry and brittle toenails without luster, etc. Older patients may also suffer from cold extremities due to the deterioration of their body functions and the loss of vascular elasticity. Smoking and other bad habits are also unfavorable factors. 2, lumbar disc herniation, lumbar spinal stenosis can cause nerve root pressure to cause abnormal sensation in the lower limbs along with cold extremities. May be accompanied by lower limb soreness, numbness, lower limb weakness and other sensations. 3, other: some endocrine system diseases such as osteoporosis, hypothyroidism, etc., some neurological diseases, anemia, etc. When the lower limb skin temperature is low and the legs are cold, you should promptly consult a doctor to clarify the cause, and according to the situation, health guidance or drug treatment, etc., in line with the indications for surgery, if necessary, surgery can be treated.