The shinbone (tibia) is one of the bones in the lower leg. Twisting (called torsion) of the tibia toward the outside (external torsion) occurs normally as the child grows and is rarely a problem. Twisting toward the inside (internal torsion) is common at birth and typically resolves as the child grows. However, a great degree of torsion may indicate a neuromuscular problem or Blount disease Bowlegs In bowlegs, what doctors call genu varum, the legs appear curved out at the knees so that the knees are more widely separated than normal. This appearance is usually created by the position... read more 
. Persistent, excessive internal torsion can lead to toe-ing in (pigeon toes) and bowlegs Bowlegs In bowlegs, what doctors call genu varum, the legs appear curved out at the knees so that the knees are more widely separated than normal. This appearance is usually created by the position... read more .
Doctors can detect this birth defect by doing a physical examination and taking various measurements of the legs.
In most children, the shinbone returns to a normal position without treatment around 5 to 6 years of age. Children who have a severe case of tibial torsion may need to wear special shoes, a cast, or leg braces.
(See also Introduction to Birth Defects of the Face, Bones, Joints, and Muscles Introduction to Birth Defects of the Face, Bones, Joints, and Muscles Birth defects of the face and limbs are fairly common. They may involve only a specific body part, such as the mouth (cleft lip or cleft palate) or foot (clubfoot). Or they may be part of a... read more .)
