Sudden pain in the lumbar spine can’t stand up straight, considering that it is caused by acute lumbar sprain, lumbar spine disease, visceral disease and other reasons. 1. Acute lumbar sprain: when the lumbar posture suddenly changes, if the force is not appropriate, may cause lumbar muscles, ligaments and other soft tissues acute injury, resulting in lumbar spine sudden pain straight back. 2. Lumbar spine disease: If you usually have lumbar spine disease, such as lumbar intervertebral disc herniation, etc., when you use your waist improperly, such as lifting and carrying heavy objects, lumbar sudden twisting, etc., it may induce an acute attack of lumbar intervertebral disc herniation, which may cause lumbar spine sudden pain and straighten up, and some of the patients may also be accompanied by radiating pain in the legs, numbness and weakness, and other symptoms. 3. visceral diseases: such as kidney stones, ureteral stones, etc., in the acute attack of these conditions, may also cause the lumbar spine suddenly appeared tugging pain straight back. There are many other causes of sudden pain in the lumbar spine, such as severe symptoms or have not been able to alleviate, you need to go to the hospital for timely diagnosis and treatment.