What is hip dysplasia?

Hip dysplasia (developmental dysplasia of the hip, or DDH) is a common condition in which a child's hip does not fully develop or is loose in the hip socket. The condition can range from very mild instability to complete dislocation of the thigh bone ball, out of the socket. Typical hip dysplasia may be present at birth or develop during the first year after birth. (Atypical dysplasia develops during adolescence.)

What causes hip dysplasia?

The cause of hip dysplasia isn't usually clear. However, here are risk factors that increase the chance of hip dysplasia in a child.

• Having a close family member with hip dysplasia, like a sibling or parent.

• Being in the breech position during the third trimester of pregnancy.

• Being assigned female sex at birth.

• Being swaddled incorrectly.

How does the doctor check for hip dysplasia?

Your child's doctor will check your newborn for hip dysplasia right after birth and at every well-child exam until your child is walking. During the exam, your child's doctor carefully moves your child's hips to see whether the thigh bones (balls) are positioned well in the hip sockets. This exam is done gently and does not hurt your baby.

Your child's doctor also looks for other signs that may suggest a problem, including

• Range of motion that is limited in either hip

• One leg that is shorter than the other

• Thigh or buttock creases that appear uneven or lopsided

If your child's doctor suspects a problem with your child's hip, you may be referred for an imaging study, to get an X-ray or ultrasound, and to an orthopedic specialist who has experience treating hip dysplasia.

How is hip dysplasia treated?

Not all cases of hip dysplasia need treatment. Many mild cases can be carefully observed by repeating imaging studies until the hips mature and stabilize.

If your child needs treatment, early treatment is important. Failure to treat this condition can result in permanent disability.

Children diagnosed with hip dysplasia before they are 6 months of age will most likely be treated with a soft brace, like a Pavlik harness. The Pavlik harness holds the legs apart in a flexed way to secure the thigh bones in the hip sockets. The orthopedic specialist tells you how long and when your baby needs to wear the brace. Your child is also examined often to make sure their hips remain typical and stable.

In resistant cases or in older children, hip dysplasia may need to be treated with a combination of braces, casts, traction, or surgery. After surgery, your child will be placed into a hip spica cast for about 3 months. This hard cast stops movement in the hips and keeps the hips in the correct position. When the cast is removed, your child needs to wear a removable hip brace for several more months. Your child may need a special car safety seat during this time.

Note: In the past, parents were told to double or triple diaper their babies. The hope was to keep the legs in a position that made dislocation less likely. This practice is not recommended. The diapering does not prevent hip dysplasia and only delays effective treatment.

For More Information

American Academy of Pediatrics

www.aap.org and www.HealthyChildren.org