Lumbar straight up all the time up legs and waist pain may be due to physiological factors, lumbar intervertebral disc herniation and lumbar vertebral osteophytes and other reasons. 1. Physiological factors: if the patient after strenuous exercise or a long time after the high load exercise, may cause the waist and lower limbs appear temporary hypoxia, lactic acid secretion over the situation, so that the waist can not straighten up, has been up legs and waist pain phenomenon, generally after resting for some time will be improved. 2. Lumbar disc herniation: If the position of the lumbar disc herniation of such patients presses the downwardly traveling sciatic nerve, when the patients stand up, the lumbar disc herniation may aggravate the pressurization of the sciatic nerve, which results in the phenomenon of lumbar and leg pain. 3. Lumbar vertebral osteophytes: occurring in the lumbar 3-4 and other parts of the lumbar spine, often manifested as lumbar vertebrae and lumbar soft tissue swelling, pain and stiffness and other symptoms. Therefore, when the patient bends down, it may be difficult to stand up. At the same time, the proliferated bone may also compress the sciatic nerve, resulting in lumbar and leg pain. Therefore, if the patient suffers from severe or persistent low back pain and difficulty in standing up straight, it is recommended to go to the hospital in time to identify the cause of the disease and target treatment.