Characteristic of blounts disease -

Ans. is 'b' i.e., Genu varus Blount's disease (Infantile tibia vara)* Blount's disease is a rare growth disorder that affect children, causing the legs to bow outwards just below the knee. Tibia vara is caused by growth retardation of the medial and posterior part of the proximal tibial physis and epiphysis due to abnormal weight - bearing stress and compression forces on varus knee. Blount's disease does not develop in infant before walking age and is not observed in non-walkers. Weight-bearing and walking are requisites for the development of tibia vara. Children with tibia vara (Blount's disease) have severe genu varum and excessive medial tibial torsion and they are early walkers.* Primary deformity in Blount's disease is tibia vera (genu varum) and associated deformities are internal tibial torsion and genu recurvatum.