Why bring your baby for hip ultrasound?
Hip ultrasound (US) and clinical examination of the infant (aged 4 weeks to 12 months) primarily serve to detect and treat in time the most common musculoskeletal conditions of infancy: developmental dysplasia of the hip (DDH), torticollis and foot deformities.
Although the vast majority of children are born healthy, timely hip US and paediatric orthopaedic examination are desirable because all problems can be treated more quickly, successfully and simply if therapy is started as early as possible.
When to bring your baby?
For term infants (from 39 weeks gestation onwards), hip US is best performed at 5–8 weeks of age.
Earlier examination is recommended for children with:
- A family history of Pavlik harness treatment or limping in childhood
- Birth in breech presentation (regardless of mode of delivery)
- Oligohydramnios during pregnancy
Positive family history, breech presentation and oligohydramnios are risk factors for DDH. However, DDH is a genetic condition present in the foetus in the uterus – it is not caused by delivery. Therefore the statement "the hips were dislocated during delivery because the baby was breech" is not considered accurate.
How is hip ultrasound performed?
In Croatia, the accepted method is Graf's technique – the infant is placed in a lateral position and the ultrasound probe is applied laterally to the upper hip region. Hip US is a subjective imaging method; technically correct examination and interpretation require knowledge and skills acquired through clinical practice.
What can be detected?
Hip US is the gold standard for detecting DDH. Dysplastic means abnormally developed – in DDH, the acetabulum (socket) in the pelvis is too shallow and the femoral head does not sit correctly, so the hip joint does not develop properly.
The goal is to determine whether the hip is correctly developed or too shallow. If dysplasia is found, treatment should begin as soon as possible. Dysplasia is not necessarily bilateral – it is usually on the left side and more common in girls.
The goal of all DDH treatments is to achieve the most correct hip joint relationship possible and subsequently optimal joint function – pain-free full range of motion. Untreated DDH leads to abnormal wear of hip cartilage, pain, limping and secondary osteoarthritis, ultimately requiring total hip replacement.
Treatment if DDH is confirmed
DDH has different clinical manifestations – degrees of severity – so treatment must be adapted to the severity of dysplasia and the child's age.
- Pavlik harness – the standard conservative treatment for most cases detected in time; positions the femoral head over the acetabulum
- Abduction nappies – for younger, less mature infants with milder dysplasia
- Hilgenreiner splint or casting – may be needed if dislocation accompanies dysplasia
All these methods aim to position the femoral head over the dysplastic acetabulum so that mechanical pressure deepens the socket. This is possible while children are young and the acetabulum is cartilaginous and can be plastically remodelled.
Unfortunately, if DDH is not detected in time and the capacity for plastic remodelling is limited, surgical treatment must be undertaken immediately. This underlines the critical importance of timely hip ultrasound examination.