Blount disease is a growth disorder that affects bones of the lower leg, causing them to bow outward. . It can affect children at any time during the growing process, but it's more common in kids under 4 and in teens. In younger kids both legs are often affected, but in teens it's usually just one. Blount’s disease is an uneven bone growth that causes the tibia to bow outward instead of grow straight.
Blount disease is very different from the type of bowlegs that are so common in babies and toddlers due to their positioning in the uterus. Babies' legs are naturally bowed. But the bowing almost always straightens out on its own once a child starts walking between the ages of 1 and 2 when the muscles of the lower back and legs are strong enough to support them in the upright position. . Most of the time bowlegs resolves on its own with time and growth. No specific treatment is needed unless the problem persists after age two.
Blount disease, on the other hand — whether it starts in early childhood or the teen years — will not correct itself over time and will only get worse if left untreated. That's why it's important to diagnose the defect early.
The most obvious sign a person might have Blount disease is bowing of the leg below the knee. In young kids this is usually not painful, but for teens it can be. Over time, Blount disease also can lead to arthritis of the knee joint and, in very severe cases, trouble walking. In rare cases, one leg may also become slightly shorter than the other.
What Causes Blount Disease?
The underlying causes are controversial: it seems to be a multifactorial disease, but the contribution of genetic factors is unknown. Blount disease can only be diagnosed in children over 2 years of age. Doctors believe the development of Blount disease is directly related to weight.
There are other underlying factors with Blount disease, though. In general, it's more common among girls, people of African heritage, kids who started walking at an early age, and those with a family member who also had it.
If your legs start bowing — especially if you also have knee pain that seems to be getting worse and can't be traced back to an injury — your doctor may consider Blount disease as a possibility. Visual observation is the first method of diagnosis. The doctor sees the problem when looking at the child or watching him or her walk. The distance between the knees is measured with the child standing with the feet together.The orthopedic doctor will do a complete physical exam and also take X-rays of your legs. X-rays help the doctor look for the abnormal bone growth patterns.
The doctor treats Blount disease depending on how old the person is and how far the disease has progressed. Young kids may simply need to wear leg braces. Most older kids and teens will need to have surgery. Many different types of surgeries can correct Blount disease. Whichever method your surgeon recommends, the procedure will be done under general anesthesia. Afterward, you'll probably need to wear a cast and use crutches for a while. You'll also probably need physical therapy. Most teens make a complete recovery finding themselves returning to all their normal activities. It ia important to stay at a healthy weight to help protect bones and joints from excess wear and tear that can damage them over time.
It must be noted that a severe untreated deformity can lead to early degenerative arthritis of the knee so early detection is important for the patient’s future wellbeing. If the child doesn't receive early treatment, Blount's disease will gradually get worse with more and more bowlegged deformity. Surgery may be needed to correct the problem.
Parents should be advised that Blount's disease might not be cured with surgery. Results are usually good when treated at a young age and at an early stage, the problem usually doesn't come back. Older patients with advanced deformity have a much higher risk of recurrence of the deformity. Patients must be followed carefully throughout their growth and development.