Hip dysplasia in babies

Also known as developmental dysplasia of the hip (DDH) or congenital dislocation of the hip

Developmental hip dysplasia is a condition where the hip joint does not form properly or is unstable in babies and young children.

Key points about hip dysplasia in babies

  1. In 1000 babies, 1 to 2 are affected by developmental hip dysplasia.
  2. Girls are 5 times more likely to get the condition than boys.
  3. Hip dysplasia is not always detected at birth, and can develop over the next few months of age. 
  4. If hip dysplasia is detected earlier, treatment is more effective and the outcome will be better. 
  5. Practicing hip-healthy swaddling can help prevent hip dysplasia and other serious hip problems. 

What causes hip dysplasia in babies?

The hip joint comprises the head of femur (ball) and pelvis (socket) and is commonly called the "ball and socket" joint. For the hip joint to function and rotate properly, the head of femur has to fit in the pelvis socket tightly.

In hip dysplasia, the socket of the hip is too shallow, so the head of femur (the ball) does not fit properly in the socket, causing the hip joint to be loose. This means it can dislocate easily. 

The exact cause of developmental hip dysplasia is not known. However, the risk factors for babies getting hip dysplasia include:

  • being female
  • being a first born baby
  • your baby being in the breech position (feet or bottom first) before birth
  • a family history of developmental hip dysplasia.

What are the symptoms of hip dysplasia in babies?

Common symptoms of hip dysplasia include:

  • one leg appears shorter than the other
  • one leg is less flexible or mobile than the other
  • your baby's thighs, buttocks or groin creases are not in symmetry (they look different from each other)
  • your toddler walks with a limp (if hip dysplasia has not been diagnosed earlier). 

What are the complications of hip dysplasia in babies?

If hip dysplasia is not diagnosed and treated early, it can get worse and cause complications such as:

  • your child learning to walk with a limp
  • severe hip pain 
  • early arthritis (wear and tear of the lining of the joint)
  • your child requiring a hip replacement surgery at a young age. 

How is hip dysplasia diagnosed in babies?

Your doctor or midwife will check your baby for this condition when they are born as part of the newborn examination. They will do some tests on your baby by moving your baby's hip joints gently.

If the condition is not detected after your baby is born, your doctor, midwife or Well Child provider will do more tests over the next few months of age, including at their 6-week check.

If your doctor is concerned, they will refer your baby to a paediatric orthopaedic surgeon. If the hips feel stable on exam but there are minor signs, or your baby is older than 4 months, your doctor may request an x-ray or ultrasound of your baby’s hips first. 

How is hip dysplasia treated in babies?

Developmental hip dysplasia is treated by paediatric orthopaedic surgeons. The treatment chosen depends based on your baby's age and the severity of the condition.

Treatment can include:

  • observation with repeat ultrasound scans and x-rays
  • a harness or a brace – a splint used to hold your baby's hips in a stable position
  • surgery. 

Talk to your baby's doctor or surgeon to find out the best treatment option. 

What is the outlook for a baby with hip dysplasia?

Not all cases are the same. However, most of the cases have good outcomes from treatment and those children are able to develop normally.

How can I prevent my baby from getting hip dysplasia?

To prevent hip dysplasia, make sure your baby's hips are not wrapped (swaddled) tightly with their legs straight and pressed together. To allow healthy hip development, the legs should be able to bend up and out at the hips. 

If you use a baby carrier, make sure it supports your baby’s hips appropriately – the thighs should be supported and the hips and knees bent (the ‘M’ position).

Read more about hip-healthy swaddling.

Learn more

The following links provide further information about developmental hip dysplasia. Be aware that websites from other countries may have information that differs from New Zealand recommendations.  

Developmental hip dysplasia Healthinfo, NZ
Developmental dislocation of the hip (congenital dislocation of the hip) Starship Paediatric Orthopaedics, NZ
Developmental dislocation (dysplasia) of the hip (DDH) OrthoInfo, US
Developmental dysplasia of the hip NHS, UK 
What is pediatric hip dysplasia? International Hip Dysplasia Institute

References

  1. Developmental dysplasia of the hip (DDH) Auckland Regional HealthPathways, NZ
  2. Developmental dysplasia of the hip Starship Clinical Guideline, NZ 

Reviewed by

Dr Sara Jayne Pietersen is a GP practicing in south-east Auckland. She has a special interest in travel medicine, paediatrics and women's health, particularly the postnatal period. She is passionate about the role exercise and nutrition play in our general wellbeing. 
Credits: Health Navigator Editorial Team. Reviewed By: Dr Sara Jayne Pietersen, FRNZCGP, Auckland Last reviewed: 20 Oct 2020