tibial femoral angle

The natural history of the tibial femoral angle is one of considerable genu varum or bowing at birth, approximately 15 degrees. There is gradual spontaneous correction to zero degrees at one and one-half to two years of age. During the next year, a valgus of 10 degrees to 12 degrees develops which gradually corrects to the normal adult value of 5 to 6 degrees valgus at about age seven years. This process is identical in boys and girls.

Diagnosis

Clinical diagnosis and x-rays are not required. Observation of child walking:
Knee caps point forward
Femur external
Tibial internal rotation cancels femur rotation
Foot points inward (due to tibial rotation)

Measuring degree of genu varum:
Child stands with medial malleoli touching
Measure distance between medial femoral condyles

http://www.doctorslounge.com/pediatrics/diseases/genuvar.htm