Developmental dysplasia of the hip (DDH) is the term used to describe the condition where the femoral head (ball) has an abnormal relationship to the acetabulum (socket). This can range from a severe dislocated hip where the ball is not in contact with the socket; to a stable hip with a shallow acetabulum (socket). Good hips to start out life are very important. If the hip joints have not developed properly when a baby takes its first steps, the scenario may be set for hip troubles later in life.
--What is developmental dyplasia of the hip (DDH)?
The hip is a ‘ball and socket’ joint. In a normal hip, the head of the hip (ball) fits snugly and tightly into the cup of the pelvis (socket).
DDH is a common childhood condition, affecting approximately 1 in 1000 babies and is more common in girls than boys (8:1). It can occur in one hip or both hips. The precise cause of DDH is not known but we know that both genetics and environmental factors influence the way the hip develops and can lead to a baby’s hip failing to develop properly.
Risk factors for DDH include a family history of DDH and breech birth. Any babies with these risk factors must have a screening hip ultrasound at 6 weeks corrected age, even if they have a normal clinical examination at birth.
Other associated risk factors are:
- multiple pregnancies (eg, being a twin or a triplet)
- decreased amniotic fluid inside the womb (called ‘oligohydramnios’)
- foot deformities present at birth
- congenital muscular torticollis (difficulty turning the head)
- plagiocephaly (misshapen head).
--How do I know if my child’s hips require medical attention?
It is not always possible to detect DDH in infants with just a clinical examination of their hips and legs.
If there are any concerns about DDH from your maternal and child health (M&CH) nurse, it is best to have a hip ultrasound (if under six months old) or a hip X-ray (if over six months old).
Although DDH may be present and diagnosed at birth, many cases may not be detectable at birth and may only be recognised later when the child begins to walk.
It is, therefore, important to have careful and regular follow-up with experienced health professionals, especially your M&CH nurse and GP.
If they have concerns about your baby’s hips, such as uneven skin creases of thighs/buttocks, hip stiffness or leg length difference, you may be referred for a hip ultrasound. If DDH is present, you will be referred to a paediatric orthopaedic surgeon and may require brace treatment.
(Link to DDH Brace Fact sheet – RCH/VPON)
--Should I be concerned?
DDH is not a painful condition in infancy and childhood and does not cause delays in gross motor milestones.
If DDH is undetected and/or untreated in infancy, the hip can become painful during teenage years and early adulthood, due to the onset of early arthritis.
Early treatment with bracing results in the best outcomes. Most babies wear a brace for 3–6 months, depending on their age and how severe their DDH is. Older babies (above six months) may require surgery to treat their DDH.
--How can physiotherapy help with DDH?
A paediatric physiotherapist can offer strategies to help with DDH treatment:
- if your baby’s hips are tight, your physiotherapist can show you gentle stretches to do at nappy changes
- a physiotherapist can show you strategies for positioning and play when your baby is wearing a brace for DDH
- a physiotherapist can help treat your baby for torticollis and plagiocephaly which can be associated with DDH.
--Will bracing delay my child’s development?
No. Brace management for DDH will not delay a baby’s gross motor milestones. They will either learn to move in the brace in a different way, or will ‘catch up’ very quickly when the brace treatment is finished.
Babies are able to roll, crawl, stand and even walk when wearing a hip brace. They do not usually require physiotherapy to help with their development while in a brace or after brace treatment is finished.
--What can I do at home?
- Do not swaddle your baby’s legs or place your baby in sleeping bags which pulls their legs together tightly. This can increase the chance of them developing DDH. Remember to have ‘loose legs’ for sleeping.
- Carry your baby around your hip or use a baby carrier which holds the baby’s legs apart.
- Encourage frequent short periods of ‘tummy time’ play every day.
- Ensure your baby experiences different positions to encourage their gross motor development—eg, side lying, supported sitting, prone play (tummy time).
- Monitor your baby’s head shape and ensure he/she can look to both sides and sleep with their head turned to both sides. Babies who favour turning to one side are at risk of developing plagiocephaly.
- Attend regular follow-ups with health professionals (eg, M&CH nurses, GP) who will monitor your baby’s hips as they grow.
