Internal tibial torsion and in-toeing with an asymmetrical angle greater on the left side can be associated with fetal positioning, the neonate sleeping in a prone position, or the child sitting on the feet. External tibial torsion may be observed from ages 4-7, mostly unilateral (right sided), and worsening with age. Surgery (osteotomy) for external tibial torsion is more likely to be recommended, but not usually until age 10 or older.
M21.80 – Other specified acquired deformities of unspecified limb
Q74.2 – Other congenital malformations of lower limb(s), including pelvic girdle
249785006 – Tibial torsion