Sacroiliac muscle strain has the following common symptoms: First, the patient’s activity is limited when squatting, which will induce lumbosacral pain, and the lumbosacral pain will be aggravated when the patient lies on the back for too long or stands for too long. Secondly, when the patient is in sitting position, there is no pain or slight pain symptoms when bending, while bending in standing position will induce lumbosacral pain. Third, when the patient is lying down, putting one side of the lower limb above the opposite knee joint will cause obvious pain in the lumbosacral region. Fourth, when the patient is in prone position, the pelvis stays motionless and the hip joints are stretched backward, which can obviously feel the pain in the lumbosacral region. Fifth, if the patient maintains the kneeling position, so that the buttocks and heels are close to each other, it will also induce the lumbosacral pain symptoms.