If a kidney stone falls into the ureter and gets stuck in the ureteral stenosis, the pain in the lower back can occur, often as colic, with paroxysmal pain, and can be accompanied by radiating pain in the small abdomen. In this case, the kidney and urological ultrasound should be performed for examination and diagnosis, and if necessary, laser lithotripsy should be performed to relieve the back pain and the pain in the small abdomen. Second, gynecological diseases, if pelvic inflammatory disease or pelvic effusion is serious, it can lead to low back pain accompanied by small abdominal pain, and can be accompanied by a feeling of small abdominal swelling, then pelvic ultrasound or CT examination should be performed for diagnosis.