A to Z: Spondyloepiphyseal Dysplasia (SED)

May also be called: SED

Spondyloepiphyseal dysplasia (spon-dih-low-ep-ih-FIZ-ee-ul dis-PLAY-zhee-uh), or SED, is a term that refers to a rare group of skeletal conditions that cause a type of dwarfism in which people have shortened trunks and limbs.

More to Know

Spondyloepiphyseal dysplasias are genetic conditions that affect the development of bones in the spine (vertebrae) and the ends of long bones that are near the joints. This results in short stature with a very short trunk and limbs, although hands and feet may be more average-sized.

People with SED usually have barrel chests, short necks, and abnormal curvature of the spine that may get worse as they age. SED also can be associated with vision and hearing problems, clubfeet, cleft palate, arthritis, and difficulty with the respiratory system as the spine curvature becomes worse.

The two main types of SED are:

1. SED congenita, in which short stature is apparent at birth.
2. SED tarda, in which a lack of growth in the trunk area may not become apparent until a child is between 5 and 10 years old.

Both types are caused by mutations in genes that are responsible for making proteins the body needs to form cartilage and bone. Most cases of SED are due to a random mutation in the genes, but the condition can be inherited from a parent.

Treatment for SED involves treating complications like vision loss and spinal curvature as they arise.

Keep in Mind

There is no cure for SED, but it doesn't reduce life expectancy. People with SED may require regular monitoring by doctors to help prevent and treat complications.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.