Sacroiliac strain is also one of the main causes of low back pain, often with acute attacks, but also some become chronic, and the course of the disease is prolonged for weeks or months. The causes are mostly related to acute sprains or prolonged labor in unfavorable positions. The disease can be triggered by the secretion of progesterone during pregnancy, which causes ligamentous laxity and increased weight and forward gravity. In acute attacks, the pain is severe on the lower back side, radiating to the buttock or groin area, but not to the sciatic nerve distribution area of the lower leg. Patients are often unable to go down to the floor or can only barely limp. Reclining and flexing the hip can relieve the pain, and in severe cases, they cannot turn over to their side. In some cases, the symptoms are not very serious, but the unilateral lower back pain is more obvious, and the patient cannot go down to the ground or work. On examination by a physician, the patient is seen to have limited straight leg elevation on the affected side and may cause increased pain in the sacroiliac region. Compression and separation of the iliac wing may cause sacroiliac pain or lead to worsening of sacroiliac pain when lying down. Most patients have significant pressure pain in the sacroiliac region. In acute sacroiliac strain, the symptoms are usually more serious, and bed rest is mostly required, and pain relievers or local closure treatment is given if necessary. Chronic patients can use traditional Chinese medicine to activate blood stasis and pain relief cream and other drugs for external application, and acupuncture and physiotherapy are effective treatment methods.