A girl’s legs do not close together may be caused by factors such as thinness and inversion of the knee. 1. Thin body shape: for some thin body or limbs of the crowd, in the thighs together when the legs can not close the situation, is a normal physiological phenomenon, do not need to worry about it. 2. Knee inversion: also known as “O” shaped legs, can be manifested as the patient’s two lower limbs stand naturally or straighten, the two heels can touch each other but the two knees can not be together, is a more common lower limb deformity, common in teenagers and children. Can be divided into physiological knee inversion and pathologic knee inversion, pathologic knee inversion can be seen in rickets and so on. If the phenomenon of girls can not close their legs together is accompanied by other obvious discomfort, it is recommended that the patient go to the hospital in time to find out the cause of the disease and then targeted treatment.