About developmental dysplasia of the hip or DDH

Developmental dysplasia of the hip (DDH) affects the hip joint in babies and young children.

It happens when the ball of a baby’s hip isn’t sitting in the correct position in the hip socket. The ball is unstable within the socket. This can sometimes cause dislocation, which is when the ball comes partially or completely out of the socket.

Usually, only one hip is affected, most commonly the left hip. But sometimes both hips are affected.

DDH can happen at birth or develop in the weeks or months after birth.

DDH can vary from mild to severe. It isn’t painful in babies. But if it isn’t treated in infancy and early childhood, it might cause pain later in life.

Signs and symptoms of DDH

If your baby or young child has developmental dysplasia of the hip (DDH), you might see the following signs, but they won’t always be obvious:

• One of your baby’s legs looks shorter. This is noticeable when your baby is on their back and their hips and knees are bent at a 90° angle.
• Your baby’s legs are tight when you try to open them to change your baby’s nappy.
• Your baby has uneven thigh creases.
• Your child limps when they start walking.

Medical help: when to get it for children with signs of DDH

You should take your child to your GP if you notice any of the signs of developmental dysplasia of the hip (DDH) above.

Tests for DDH

Doctors and/or midwives do a very careful physical examination of both hips in all newborn babies in the first few days of life.

Your GP or child and family health nurse will do these examinations again at 6 weeks. And your child and family health nurse will check your baby’s hips at every appointment in the first 12 months of your baby’s life.

If your health professional suspects developmental dysplasia of the hip (DDH), your baby might get a hip ultrasound or X-ray.

If you have a family history of DDH or your baby was breech, a hip ultrasound might be recommended at 8 weeks of age.

You might be referred to a paediatric orthopaedic surgeon for a specialist opinion.

Treatment for DDH

If your baby is diagnosed with developmental dysplasia of the hip (DDH) when they’re a newborn or young baby, doctors might recommend a brace. Babies with braces usually have hip ultrasounds every 4-6 weeks to monitor their progress.

Babies with mild to moderate DDH usually wear braces for at least 3 months. For more severe DDH, babies wear braces for at least 6 months. Babies with more severe DDH might need surgery too.

The earlier DDH is diagnosed and bracing is started, the better. If babies are older than 5 months of age when diagnosed with DDH, they’re more likely to get complications and need complex treatment like surgery.

DDH prevention

Developmental dysplasia of the hip (DDH) can sometimes be caused by wrapping your baby’s legs too tightly, so they’re straight and can’t move. If you wrap your baby, keep their legs loose so that their hips and knees can bend.

Some babies really like to lie with their head turned to one side. This can affect the position of your baby’s hips. It’s important to alternate your baby’s head position for sleep from right to left. This can also help to prevent your baby from getting plagiocephaly, which is an uneven or flattened head.

Regular tummy time can also encourage babies to alternate their head position.

To learn more about how to wrap your baby safely, check out our video on wrapping a newborn or our illustrated guide to wrapping babies.

Risk factors for DDH

Risk factors for developmental dysplasia of the hip (DDH) include:

• family history of DDH
• breech position in the womb
• low amniotic fluid in the womb
• twin pregnancy
• first pregnancy
• sex – DDH is 4 times more common in girls than boys
• plagiocephaly, clubfoot, positional talipes and other problems associated with babies’ positions in the womb.