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Developmental hip dysplasia

Pūtau rerekē ki ngā hope whanaketanga

Diagram showing hip dysplasia, subluxation and dislocation

If your pēpi/baby has developmental dysplasia of the hip, or DDH, it means their hips are unstable or have not fully developed. This can be because the socket of their hip joint (called the acetabulum) is not deep enough, or the ball part of their thigh bone (the femoral head) is in the wrong position in the socket. If the ball is not sitting in the socket at all, it's called a dislocation.

The problem is usually there at birth, but it can also develop during infancy or childhood.

It's important to diagnose and treat DDH as early as possible. If it's not treated it can lead to painful hips, limping and reduced strength. Your tamaiti (child) could also develop arthritis early in life.

Causes of DDH

We do not know the exact cause, but some things can make tamariki (children) more likely to develop DDH. These include:

Girls are affected six times more often than boys.

Preventing DDH

How the legs of your pēpi are positioned during the first few months of their life may affect their risk of developing DDH. Consider hip-healthy methods of wrapping (swaddling) and equipment for pēpi such as car seats.

Avoid having the legs of your pēpi held straight and tight together. Instead put their hips and knees in the position known as the M shape. Read more detailed information about preventing DDH.

Diagnosing DDH

Your midwife, doctor and Plunket nurse will examine your pēpi for hip problems at birth and several times during their first months of life. If a doctor suspects your pēpi has a hip problem, they will arrange an ultrasound scan of their hips. If your pēpi is 6 months or older, they will have an X-ray.

Pēpi with a higher risk of DDH (due to family history, breech birth or other womb factors) will usually be offered an ultrasound scan at about 6 to 8 weeks of age.

Treating DDH

If your pēpi has DDH, a paediatric orthopaedic surgeon will assess their hips and look at the ultrasound scan or X-ray. The surgeon will decide how best to treat the DDH. This will depend on how old your pēpi is and the severity of the condition.

Some babies may need to be treated using a harness or brace. Surgery may be needed in more severe cases or if the bracing is unsuccessful.

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On the next page: Treating DDH using a harness

Written by HealthInfo clinical advisers. Last reviewed June 2022.


Page reference: 52939

Review key: HIBOW-85151