Developmental Dysplasia of the Hip

During physical examination, hip instability, where the ball comes out of the socket, produces a "clunk" that can be felt as the hips move. With a dislocated hip, range of motion is reduced and the affected lower limb appears shorter than the other, non-affected side.

If DDH is suspected, the next step for a child less than 6 months of age is an ultrasound. This painless and non-invasive test, which takes about 15 minutes, is done in the doctor's office. Ultrasound provides a picture of the ball and socket, from which the severity of the DDH can be determined.

For a child older than 6 months, the best test is an X-ray. This test is also painless and non-invasive, and the radiation exposure is less than the routine background radiation present in the environment.

Once a child with DDH begins to walk, the dislocated hip will produce a limp. Again, this is considered a silent condition since the child most likely will not complain about the limb. If both hips are dislocated, the child will waddle from side to side, which may even be considered cute by onlookers.

In special cases, DDH is not diagnosed until a child reaches the teenage years. This typically occurs in girls who begin to experience hip pain while performing physical activities, such as playing sports.

Reviewed by health care specialists at UCSF Benioff Children's Hospital.

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UCSF Clinics & Centers


Orthopedic Clinic
1825 Fourth St., Fifth Floor, 5B
San Francisco, CA 94158
Phone: (415) 353-2967
Fax: (415) 353-2299
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