1.Chronic lumbar strain generally has a slow onset and a long course, without an obvious history of acute trauma, but with a long-term history of gradual onset after working or bending, or sitting or other poor posture. 2. Some patients have acute lumbar sprain without timely and reasonable treatment and turn into chronic lumbago. 3. Early symptoms of patients are generally mild, often feeling soreness, swelling, sleepiness, heaviness and discomfort in the lumbar region, aggravated after activity and exertion, alleviated after rest, and can be alleviated by changing the position frequently. As the disease progresses, the back pain increases and the patient cannot sit or stand for a long time and often has to change position. After sleeping for a period of time at night, back pain starts to appear and gradually worsens, even making it difficult to sleep at night. Patients like to pound their waist with both hands to relieve the pain. Symptoms can be significantly relieved by treatment such as lumbar massage or hot compress. 4.Lumbar muscle strain, if it exists for a long time, can still cause pain in other areas, such as intercostal neuralgia, abdominal pain, chest and back pain, pelvic organ pain, such as dysmenorrhea, menstrual disorders, anal perineal pain, etc. 5. Due to the different types of strain in patients, there can be different degrees of pressure pain in different parts during examination, but its degree is generally lighter than that of acute lumbar sprain. Lumbar muscle strain often has pressure pain at the sacral or iliac appendages of the lumbar muscle or other parts of the lumbar muscle, and the bilateral lumbar muscle is located in the combined thoracolumbar area with the palm of the hand, but some patients feel pain relief or comfort. If the supraspinous ligament and interspinous ligament are strained, there is pressure pain at the supraspinous ligament or interspinous ligament. The numbness of the skin at the site of the strain is often without clear sensory impairment.