Blount's Disease

Definition

Definition of Blount's Disease
Blount's disease is a growth disorder of the tibia (shin bone) that causes the lower leg to angle inward, resembling a bowleg.

Symptoms

Symptoms of Blount's Disease
Bowing of one or both legs that may:

1. Be rapidly progressive
2. Appear asymmetric
3. Primarily occur just below the knee

Causes

Causes of Blount's Disease
Blount's disease occurs in young children and adolescents. The cause is unknown but is thought to be due to the effects of weight on the growth plate. The inner part of the tibia, just below the knee, fails to develop normally, causing angulation of the bone.

Unlike bowlegs, which tend to straighten as the child develops, Blount's disease is progressive and the condition worsens. It can cause severe bowing of the legs and can affect one or both legs.

Diagnosis

Diagnosis of Blount's Disease
Physical examination shows that the lower legs angle inward. An x-ray of the knee and the lower leg confirms the diagnosis.

Treatment

Treatment of Blount's Disease
Children who develop severe bowing before the age of 3 may be treated with bracing. However, bracing may fail, or bowing may not be detected until the child is older. In some cases, surgery may be performed. Surgery may involve cutting the shin bone (tibia) to realign it, and sometimes lengthen it as well.

Other times, the growth of just the outer half of the tibia can be surgically restricted to allow the child’s natural growth to reverse the bowing process. This second, much smaller surgery is most effective in children with less severe bowing and significant growth remaining.

Prognosis

Prognosis of Blount's Disease
Return to normal function and cosmetic appearance is expected if the knee can be properly aligned.

Prevention

Prevention of Blount's Disease
Weight loss for overweight children may be helpful.