The child’s knee protrudes from the inside of the leg is not straight, folk known as X-shaped legs, if it is bilateral protrusion, may be rickets and other diseases caused by vitamin D supplementation as prescribed by the doctor for treatment, the serious cases may require surgery. For rickets caused by oral vitamin D, calcium carbonate and other oral prescriptions to restore normal calcium and phosphorus metabolism; if there is a serious deformity, surgical correction is feasible. However, it should be noted that some babies are younger, with about 2-3 years old, there can be physiological knee valgus, in this case there is no need for special treatment, you can wait for the baby’s natural growth and development, more at about 4 years old can gradually straighten. If the child’s knee protrudes from the inside of the leg is not straight, there may be other possibilities, such as knee injury, etc. If there is any discomfort symptoms, you should consult a doctor in a timely manner, to clarify the cause of the disease, and standardized treatment under the guidance of the doctor.