The causes of right-sided lumbar pain are relatively numerous, and are commonly found in the following clinical causes: first, lumbar muscle strain. Because of excessive weight-bearing of bilateral lumbar muscles and prolonged improper sitting posture leads to lumbar muscle strain, which can cause pain in the right side of the back. Second, lumbar disc herniation. A herniated lumbar disc that irritates the nerve roots on the right side can cause pain in the right side of the back. It is also common in urinary system diseases, especially urinary stones. Kidney or ureteral stones on the right side can lead to right-sided back pain, and the pain is more intense.