Kidney stones cause lumbar pain in two places: 1. the rib spine point, which is the junction of the 12th rib and the spine. 2. the rib lumbar point, which is the junction of the psoas major muscle and the 12th rib. If there is pain in both areas, you may have stones or pyelonephritis. Both pyelonephritis and kidney stones can cause pain in this area, which can be identified by imaging, for example, if stones are found on ultrasound, pain in this area is caused by stones, and if stones are not found on ultrasound, pain in this area is caused by pyelonephritis. The pain may radiate to the back or to the lumbar muscles. Some patients may have lower abdominal radiation, but the pain is most obvious in this area, which is also called the trigger point. For other causes of low back pain, the location of the pain is not clear, and the pain is more widespread, such as pain caused by lumbar disc herniation or lumbar muscle strain, which is not in this area. There is no relationship between changes in