Acute back sprain is commonly known as back sprain in the folk. It is more common in clinical practice, especially in manual laborers; it is more common in those who occasionally participate in sports or labor without preparing for physical activities in advance, and this situation is more common in those who sit in the office all year round. The incidence of this disease varies greatly according to the scope of treatment of each hospital, accounting for about 5% to 20% of orthopedic outpatient cases. However, in recent years, due to the continuous improvement of working conditions, its incidence has been significantly reduced. Acute back sprain patients are more common in men than in women. Most of them are young and middle-aged, and there are fewer young and old patients. Although patients with this disease can be seen in all walks of life, more than 60% are heavy manual laborers and athletes who have a large amount of activities, and mental workers who occasionally do heavy work are also prone to it. The range of lesions of this disease includes the myofascial tissue from the lower back to the sacroiliac part, that is, the two anatomical areas of the thoracolumbar segment and the lumbosacral region. However, in clinical practice, because its manifestations and treatment principles are basically similar, they are now explained together.