Hip joint ultrasound in babies for the detection of developmental dysplasia of the hip – a screening test that should be performed on everyone!

What is DDH (Developmental Dysplasia of the Hip)?

This is a disorder in the development of the hip joint.

The hip joint is shaped like a ball and socket. Occasionally, a developmental issue arises that causes a mismatch between the femoral head (the ball) and the hip socket. In DDH, the socket (part of the hip bone) is too shallow, and the femoral head sits unstable—partially or entirely outside the socket. This misalignment impairs joint function and leads to characteristic signs and symptoms, as described below.

What are the different causes of DDH?

As with many conditions in medicine, the exact cause of DDH remains unclear. Multiple genetic and environmental factors may contribute. Known risk factors include:
– First birth
– Female sex
– Breech position
– Reduced amniotic fluid
– Multiple fetuses (twins, triplets, etc.)
– Family history of DDH

However, approximately half of all DDH cases occur without any identifiable risk factors. Additionally, DDH frequently co-occurs with other congenital issues, such as metatarsus adductus and torticollis. If one of these disorders is present, the likelihood of another rises significantly—about 20% of infants have two or more of these conditions.

What is the prevalence of DDH?

DDH is relatively common, affecting approximately 7–8 in every 1,000 newborns. It can manifest either during fetal development or within the first year of life.

What are the signs and symptoms of developmental dysplasia of the hip?

Symptoms depend on severity and may include:
– Asymmetrical thigh or buttock folds
– Limited leg abduction
– Apparent leg length discrepancy
– Limping in walking children

Mild cases of DDH are often asymptomatic and only detectable via imaging, such as ultrasound or, later, x‑ray. Early detection remains the goal.

How is DDH diagnosed?

Diagnosis combines risk evaluation, physical exam, imaging, and sometimes auxiliary testing.

Physical examination – In newborns, signs of instability or asymmetry may be noticed before discharge or at early pediatric visits. Examiners may detect restricted abduction, thigh‑fold asymmetry, or even audible “clicks” during hip movement. However, milder cases may present no physical signs at all, underscoring the need for regular hip checks during the first year.

Auxiliary tests – Hip ultrasound is the most common imaging test in infants, using standard ultrasound equipment to assess joint structure and measure relevant angles. Findings are graded (commonly from I–IV) to determine severity and guide treatment. In older infants (over one year), x‑rays become more useful. A detailed discussion by a radiologist is available here on our site.

Should ultrasound imaging be performed on all neonates or only those at high risk?

Some countries mandate universal neonatal hip ultrasound screening, while others reserve it for high-risk infants only. Arguments against universal screening include potential overdiagnosis and strain on specialist resources. However, physical exams alone may miss mild or developing cases. Many specialists recommend hip ultrasound for all newborns during the first few weeks, regardless of risk factors, to maximize early detection.

When should hip ultrasound imaging be performed on a neonate?

If any signs of hip imbalance are noted at birth, ultrasound should be performed promptly. Otherwise, scheduling an ultrasound around four weeks of age is optimal. This timing allows early detection of developing DDH. Additionally, routine pediatric examinations throughout the first year should include hip stability checks.

What is the treatment for DDH?

Treatment varies depending on age, severity, and associated conditions. The aim is to reposition the femoral head into the socket to allow normal development of the joint.

Pavlik Harness – In infants under six months, a Pavlik harness maintains hip flexion and abduction while permitting movement to encourage joint development. Worn nearly full-time initially, usage transitions primarily to bedtime over several weeks, with frequent follow-ups. When detected early, this method succeeds in about 95% of cases.

Hip surgery and spica cast – If the harness fails, surgical reduction under anesthesia followed by immobilization in a spica cast may be required. This approach is less common when DDH is detected early but becomes necessary in older infants or unresponsive cases.

Does DDH have any implications for the future?

Early diagnosis and treatment lead to excellent outcomes—normal hip function without pain or limitations. However, late or inadequate intervention increases the risk of persistent joint dysfunction, uneven leg length, and early onset osteoarthritis, often requiring surgery such as hip replacement. With prompt, proper care, DDH no longer impairs long-term health.

In summary, DDH is a common congenital hip condition that can have serious consequences if left untreated. Early detection through vigilant screening and timely intervention ensures successful outcomes in nearly all infants. Maintaining a high diagnostic suspicion is essential. We recommend hip ultrasounds and orthopedist evaluations for all newborns—especially those with risk factors or abnormal exam findings.

Good luck!