Developmental Dysplasia of the Hip (DDH)
DDH is when the hip joint does not develop properly in infancy. Diagnosed early, it can often be treated with a simple harness.
Developmental dysplasia of the hip (DDH) is when the hip joint does not develop normally in infancy. The socket may stay shallow, the head of the thigh bone may be loose in the socket, or it may be completely out of it. Treatment is much simpler and more effective when DDH is found early, which is why hip screening in babies is so important.
Risk factors
- Being a girl
- A family history of DDH
- Breech position in the womb
- A first pregnancy and conditions that cause crowding in the womb
- Tight swaddling with the legs held straight
Signs
- A difference in leg length
- Uneven thigh and buttock creases
- Limited outward opening of the leg during nappy changes
- In walking children: a limp, a waddling gait or toe walking
Many babies show no obvious signs, which is why all babies are advised to have an examination and an ultrasound, even without risk factors.
Diagnosis
Special hip tests are performed in the newborn period and in the first months. Hip ultrasound (the Graf method) is the most valuable test in the first months. As the bones ossify, usually after 4-6 months, X-rays are used.
Treatment
Treatment depends on the child’s age and the degree of dysplasia.
- 0-6 months: A Pavlik harness holds the hips bent and spread outwards. This position helps the head settle into the socket and the socket develop. The harness is worn for weeks, with regular ultrasound checks.
- 6-18 months: If the harness is not enough or diagnosis is late, the hip is put back in place under anaesthesia without an incision and a hip spica cast is applied.
- 18 months and older: Open surgery is usually needed. The hip is put back in place, and corrective operations on the pelvis and thigh bone may be added.
About swaddling
Traditional tight swaddling with the legs straight and together can harm hip development. Babies’ legs should be free to bend and open.
What happens without treatment?
Untreated DDH can lead to a limp, a difference in leg length and early arthritis later in life. Early diagnosis and treatment prevent most of these problems.
Life with a Pavlik harness
The Pavlik harness is adjusted so the baby can kick freely while the hips stay in the correct position. Its settings should only be changed under medical supervision. Parents learn to change nappies without removing the harness and to check the baby’s skin regularly where the harness touches.
When carrying the baby, the “frog” position with the legs spread and the knees bent should be maintained. When choosing a baby seat and car seat, choose models that allow the legs to rest in this position. During harness treatment, regular ultrasound checks follow the hip’s development, and the timing for stopping the harness is decided from these checks.
The cast period
Babies whose hip is put back in place, with or without an incision, are placed in a cast that covers the waist and legs (a hip spica cast). The cast is usually worn for a few months and may be changed under anaesthesia during this time. Keeping the cast clean and dry, tucking the nappy properly at the cast edges and checking the skin for irritation are important. Families are given detailed advice on care during this period.
Long-term follow-up
After treatment, hip development is followed with X-rays at intervals throughout growth. In some children the socket does not develop enough, and corrective operations may be needed later. Regular follow-up ensures this is noticed in time.
Frequently asked questions
When should my baby have a hip ultrasound?
It is usually recommended in the first months. Babies with risk factors may be checked earlier. You can plan the timing with your paediatrician.
Is the Pavlik harness uncomfortable for my baby?
Babies usually get used to it quickly. You will be shown how to handle nappy changes, bathing and daily care.
Will the hip be completely normal after treatment?
With early diagnosis and appropriate treatment, the hip develops normally in most children. Check-ups at intervals are recommended throughout growth.
Is DDH painful?
It is usually not painful in infancy, which is why screening without waiting for symptoms is important. Untreated cases may cause pain later in life.
Is my sibling's baby also at risk?
A family history of DDH is a risk factor. Mention it to the paediatrician so the baby's hip examination and ultrasound are done on time.
Does double nappying prevent DDH?
There is no evidence that double nappies prevent or treat DDH. Babies diagnosed with DDH should be treated with a proper harness or cast.
The information on this page is general and does not replace an examination. An examination is needed to decide which treatment suits you.