The causes of pain on the right side of the waist may be related to lumbar muscle strain, lumbar disc herniation, spinal stenosis and other conditions, as follows: 1. Lumbar muscle strain: high-intensity or long-term right lumbar muscle overactivity, or keep bending for a long time and other bad postures, so that the lumbar muscles have been in a state of tension may lead to lumbar muscle strain, which causes pain when bending on the right side of the waist. 2. Lumbar disc herniation: the nucleus pulposus of the lumbar intervertebral disc protrudes and compresses the surrounding adjacent spinal nerve roots under the action of external factors, and when the right side of the nerve is severely compressed, it can be manifested as the symptom of the right side of the lumbar pain, and the lumbar vertebrae are subjected to increased force when bending, which aggravates the pressure on the nerve, and thus leads to the pain of the right side of the lumbar pain when bending. 3. Spinal stenosis: lumbar vertebrae, ligamentous lesions can lead to narrowing of the nerve root canal, spinal nerve root compression, when the right side of the nerve root compression is serious, then the left side of the lumbar pain, bending the waist increased lumbar activity, there is a lumbar pain when bending on the right side of the waist and so on. The right side of the waist when bending pain may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.