What is Developmental Dysplasia of the Hip?
Developmental Dysplasia of the Hip (DDH) is a condition where the hip joint doesn’t develop properly. It affects between 1-3% of newborns. The hip is a ball and socket joint and when it develops normally the ball sits deep within the socket and is very stable. In DDH, the ball is not as stable within the socket and can dislocate. When diagnosed early DDH can be successfully treated, but if left untreated the condition can cause a painful limp and arthritis later in life.
Babies are generally screened for DDH at birth and again at 6 weeks of age, but the tests to check for DDH can be difficult to perform by even the most experienced health professionals. Sometimes DDH is diagnosed at birth, but sometimes it isn’t identified until the child begins to walk.
What are the symptoms?
Babies/children may have the following symptoms:
The skin creases around the bottom are asymmetrical (i.e., the left and right side look different)
One hip feels stiff compared to the other, especially when moving the knees apart (e.g., during nappy change time)
One leg turns out
One leg is longer than the other
If the child is walking, limping or leaning to one side
If you notice any of the above symptoms in your baby/child, you should consult your child's GP or Paediatrician for further assessment.
What causes DDH?
The exact cause of DDH is unknown, but it is more common in:
First born babies
Girls
Babies in the breech position
Babies with a family history of DDH (e.g., a sibling or parent with DDH)
Babies who have Congenital Muscular Torticollis ('twisted neck')
When the baby is crowded in-utero (e.g., twins, or low levels of amniotic fluid)
When the baby is swaddled too tightly around the legs
How is it treated?
The treatment for DDH depends on how severe it is and when it is diagnosed. Babies who are diagnosed with DDH are usually prescribed a splint as the first line of treatment. Two commonly used splints are called the ‘Pavlik Harness’ and the ‘Dennis Brown Bar’. These splints hold the legs in a specific position (knees bent up and out) so that the ball sits deep within the socket, allowing the joint to develop. The splints need to be worn for several months to allow the hip joint time to develop. This can be a daunting prospect for parents, but when worn as recommended, they are generally very effective in treating DDH.
Wearing a splint to treat DDH does not mean babies can’t continue to develop their gross motor skills. A Paediatric Physiotherapist can show you different ways to position babies with splints for tummy time so they can continue to develop their muscle strength.
If the splint is unsuccessful or if DDH is diagnosed late, a procedure to re-align the hip joint under general anaesthetic or surgery may be required.
What can be done to prevent DDH from developing after birth?
Swaddling your baby using the correct technique can help to reduce the risk of DDH. When swaddling your baby, there should be plenty of room for the legs to fall out to the side with the knees bent (i.e., in ‘frog leg position’). This is a good position for the hips to develop when the baby is sleeping.
If you have any concerns about the way your babies hips move when you change their nappy, or notice that one side looks different to the other you should consult your GP or Paediatrician for further assessment.
References:
Atalar H., Sayli U., Yavuz O.Y., Uras I., Dogruel H. (2007). Indicators of successful use of the Pavlik harness in infants with developmental dysplasia of the hip. International Orthopaedics, vol. 31, pp:145-150.
Alsaleem, M. Set, K.K. & Saadeh, L. (2015). Developmental Dysplasia of the Hip. Clinical Pediatrics, vol. 54(10), pp: 921-928.
Bracken, J., Tran, T.. & Ditchfield, M. (2012). Developmental dysplasia of the hip: controversies and current concepts. Journal of Paediatric and Child Health, vol. 48(11), pp: 963-973.
Sewell, M.D., Rosendahl, K. & Eastwood D. M. (2009) Developmental dysplasia of the hip. British Medical Journal, vol 339(7732), pp:1242-1248.
Shipman, S.A., Helfand M., Moyer V.A., Yawn B.P. (2006). Screening for developmental dysplasia of the hip: a systematic literature review for the US Preventive Services Task Force. Paediatrics, vol: 117, pp: 557-576.
Schwend, R.M., Schoenecker, P., Richards, B.S., Flynn JM, Vitale, M. (2007). Screening the newborn for developmental dysplasia of the hip: now what do we do? Journal of Paediatric Orthopaedics, vol. 27(6), pp: 607-610.
Tecklin, J.S. (2008). Pediatric physical therapy 4th ed. Philidelphia: Lippincott Williams & Wilkins.