The pain on only one side of the waist may be caused by the following reasons: 1. The patient has been carrying weight for a long time, and the pressure on only one side of the waist is too great, which causes damage to the muscles on one side of the waist, resulting in pain on one side of the waist. 2. The waist may be cold, that is, this side of the waist is exposed to wind, resulting in poor local qi and blood flow, which in the long run will cause the waist muscles to be in a state of tension, which in turn will cause pain. 3. The patient may be affected by the work, maintaining the same posture for a long time, causing uneven force on one side of the waist, which may lead to pain in the waist. 4, it may be due to the degeneration of body functions in the human body, such as osteophytes or osteoporosis, causing pain on one side of the waist. 5, it may be caused by diseases, such as diabetes or rheumatoid arthritis, as well as male kidney deficiency and female gynecological diseases, which can lead to pain on only one side of the waist. pain occurs on only one side.