Multiple congenital exostosis

Multiple congenital exostosis, also called EXT is a disease that causes multiple tumors called osteochondromas. The tumors are benign, meaning they are not cancerous, and they appear on the surface of bones. Most often the long bones (such as in the legs and arms) are affected, but the osteochondromas can also occur on bones such as the ribs and spine. The number and placement of the osteochondromas is different for every person with EXT, and there is no way to predict where they will be.

Symptoms of EXT include having a short stature, uneven limb length, hip dysplasia (improper development of hip joint), pain when walking, and pressure on the nerves/spinal cord.

The tumors are not detectable at birth, but are usually diagnosed at age 3. In almost every case, the osteochondromas are formed by age 12, and no new tumors are known to grow after adolescence. EXT can be diagnosed prenatally using DNA testing, or after birth with x-ray scans and DNA testing.

There is no way to prevent EXT, but pain management, surgery, and physical therapy are the most common forms of treatment. It is also important for individuals with this disease to be monitored regularly for any cancerous findings in the tumors because there is a chance that the osteochondromas could become cancerous. Most people with EXT live long lives relatively unaffected by the disease. If you have been diagnosed with this condition, talk to your doctor about the the best treatment options for you.

Description Last Updated: Jan 15, 2018