Genu varum and valgum is physiologic (normal) at certain points in a child's development. Infants and children up to approximately 2 years of age frequently exhibit genu varum. Internal tibial torsion often co-exists with genu varum and may to accentuate the 'bow-legged' appearance. Children with other abnormalities such as short stature should be investigated with x-rays to determine if this is part of a generalized skeletal abnormality (or skeletal dysplasia). Radiographs are otherwise deferred unless the deformity is extreme or progressive. Non-physiologic genu varum may be the result of abnormalities of bone mineralization (rickets), skeletal dysplasia or "Blount's disease", a condition of unknown etiology where the medial tibial growth plate becomes disturbed and does not grow normally. Between the ages of 2 and 3 years, most children develop genu valgum. This may exceed the normal 5-7 degrees seen in adults and usually peaks at about 36 months of age.