A sudden pain in the lower back that prevents you from standing up may be due to sprains, herniated discs and kidney stones. 1. Sprain: Improper posture during activities may cause sprain, which is manifested by a sudden sharp pain. At this time, you should stop the activity in time and pay attention to rest to avoid aggravation of sprain. 2. Herniated lumbar disc: Herniated lumbar disc may show sudden pain symptoms. The patient can be treated with medication or surgery to relieve the symptoms. 3. Kidney stones: when suffering from kidney stones, due to the stone stimulation of the kidney mucosa, resulting in sudden pain, this time should be promptly admitted to the hospital for treatment. Sudden pain in the waist can not stand up, may also be due to cold, lumbar vertebrae small joint disorders and other reasons, should go to the hospital in time for treatment.