Leg pain and weakness can be caused by the following conditions: first, degenerative changes in the lumbar spine, osteophytes or lumbar disc herniation compressing the nerve roots, the patient will experience lower limb pain, lower back pain and numbness in the lower limbs, and even restricted movement, which occurs due to weight bearing and exertion. With age, the bone degenerates and the fibrous ring becomes less elastic, and in severe cases, spinal stenosis may occur. Second, there are also some patients are caused by arterial system diseases, the common is atherosclerosis occlusion, the elderly appear more often, should have a history of coronary heart disease, hypertension disease. Because atherosclerosis is a systemic disease, patients may also experience pain, coldness, and numbness in the lower extremities, especially after activity will induce an increase in symptoms.