During the practice of nephrology clinic, we met a large number of patients with low back pain, who had the experience of going to major hospitals and thought that it was “kidney pain” and that there was something wrong with their kidneys, but after examination, no problem was found and they asked for an explanation. In fact, clinically, 90% of patients with low back pain are suffering from chronic lumbar muscle strain or chronic fatigue. urinary routine, kidney ultrasound examination, can find the problem. 2, spinal diseases: including osteophytes, disc prolapse, spinal infections (especially tuberculosis), spinal tumors (primary or metastatic), and ankylosing spondylitis. These diseases are mostly accompanied by pain or abnormal sensation in the lower extremities, and special movements of the spine or spinal imaging can reveal the problem. 3, radiating or involving lumbar pain: such as angina pectoris, chest or lung infection, etc. 4.Lumbar muscle strain: As mentioned earlier, this is the main cause of low back pain. Many patients say, “I’m not doing any heavy work, how can I have a lumbar muscle injury? In fact, lumbar muscle strain is a forced contraction tension of the lumbar muscle in a sustained period of time, resulting in the accumulation of metabolic products such as lactic acid, just like the calf muscle pain that must occur in people who have not exercised for a long time and suddenly run for a longer period of time.