Blount disease is an extreme case of bow legs that children don’t grow out of.
Bowlegs also known as tibia varum (singular) or tibia vara (plural) are common in toddlers and young children. The condition is called physiologic tibia varum when it’s a normal variation. The child will grow out of this type of bowing.
Most toddlers have bowlegs from positioning in utero (in the uterus). This curvature remains until the muscles of the lower back and legs are strong enough to support them in the upright position. By the time the child is three years old, this bowing should be much improved.
In some cases abnormal growth of the bone causes the bowing to get worse instead of better over time. This condition is called Blount’s disease or pathologic tibia varum.
With Blount disease there is an abnormal amount of compressive force across the growth plate. This causes growth to stop and deformities to form. The younger the child is when this problem is discovered, the greater the chances for more deformity.
Previous studies show that left untreated, Blount disease gets worse. The deformity becomes greater. The child’s walking pattern will be affected. There can be enough of a difference from side to side to cause one leg to be shorter than the other. Early arthritis can develop, too.
Early treatment is the key to a successful result. The child’s parents should be made aware of the likely results without treatment.