The newborn hip examination is one of the more skilled components of the routine postnatal check. It requires both experience and technique. The Barlow and Ortolani manoeuvres can detect unstable or dislocated hips that look entirely normal on external examination, but false negatives do occur, which is why the examination is repeated at the six-to-eight-week check and why parents are advised to watch for signs of asymmetry as the baby grows.
When DDH is found early, the Pavlik harness is a remarkably effective treatment. It simply holds the hips in the optimal position for the socket to deepen around the femoral head — no surgery, no casting, just positioning. The earlier it is fitted, the higher the success rate. Late-diagnosed DDH, sometimes found only when a toddler starts walking with a limp, requires more complex treatment.
Healthbooq (healthbooq.com) covers newborn health and common conditions of early infancy.
What DDH Is
The hip is a ball-and-socket joint. The ball (femoral head) sits inside the socket (acetabulum). In DDH, the socket may be too shallow to hold the ball securely, the ball may sit partially outside the socket (subluxation), or the ball may be completely outside the socket (dislocation). The condition exists on a spectrum. Mild acetabular dysplasia can resolve spontaneously; frank dislocation requires active treatment.
DDH is not a static condition — it can progress or regress. Some hips that are unstable at birth normalise over the first few weeks as ligamentous laxity (influenced by maternal hormones during pregnancy) resolves. Others that appear normal initially become dysplastic as growth proceeds. This is why late presentation occurs even when newborn screening has been performed correctly.
Who Is at Higher Risk
The incidence of DDH requiring treatment is approximately 1 to 2 per 1,000 live births, but hip instability detectable at birth is more common. Risk factors are well established:
Female sex accounts for around 80 per cent of cases — female infants are more affected by maternal oestrogen and relaxin, which increases ligamentous laxity. Breech presentation at any point in the third trimester (not just at delivery) significantly increases risk. A first-degree family history of DDH doubles or triples risk. Oligohydramnios and multiple pregnancy also increase risk, probably by limiting foetal movement.
Newborn Screening
All newborns in England should receive a hip examination as part of the Newborn and Infant Physical Examination (NIPE) programme within 72 hours of birth and again at six to eight weeks.
The Barlow test attempts to provoke dislocation of a located but unstable hip: the hip is flexed to 90 degrees and adducted while posterior pressure is applied. A palpable "clunk" (not a click — soft clicks without a clunk are common and usually insignificant) indicates the femoral head slipping out of the acetabulum.
The Ortolani test attempts to relocate a dislocated hip: the hip is flexed to 90 degrees and abducted while anterior pressure is applied. A palpable clunk indicates the femoral head returning to the socket.
Neonates with risk factors (breech presentation, family history, or clinical concern at examination) should be referred for hip ultrasound at around six weeks. Ultrasound, using the Graf classification system, provides quantitative assessment of acetabular morphology and is far more sensitive and specific than clinical examination alone.
Later Presentation
Despite screening, DDH is not always detected at birth. Late-presenting DDH may become apparent when a child starts weight-bearing. Signs include: limited hip abduction (the thigh cannot be spread widely when lying on the back), asymmetrical thigh or gluteal skin folds, leg length discrepancy, and, once walking begins, a Trendelenburg gait (the pelvis drops to the opposite side on standing on the affected leg) or a waddling gait if both hips are affected.
Any child with unexplained gait abnormality, persistent limited hip abduction, or leg length discrepancy should be referred for orthopaedic assessment.
The Pavlik Harness
The Pavlik harness is a soft splint system that holds the hips in flexion and abduction — the "frogleg" position — which is the optimal posture for the acetabulum to deepen around the femoral head. It is the first-line treatment for DDH in the first six months of life.
Success rates with the Pavlik harness are highest in the youngest infants. For hips that are dislocatable or subluxed (but still reducible), success rates of 85 to 90 per cent have been reported. For frankly dislocated hips, success rates are lower (around 60 to 70 per cent).
The harness is typically worn full-time (24 hours a day) for the first few weeks, then part-time as the hip stabilises. Parents are taught how to dress the baby over the harness, how to check skin for pressure marks, and how to keep the harness clean. Normal bathing is usually possible.
Hip ultrasound is repeated at intervals during harness treatment to confirm progress.
If the Pavlik harness fails or DDH is not detected until after six months of age, treatment typically involves a period of closed reduction under general anaesthetic followed by a hip spica cast. Surgery is required in some cases of late-diagnosed or treatment-resistant DDH.
Key Takeaways
Developmental dysplasia of the hip (DDH) is a spectrum of conditions in which the hip joint does not develop normally, ranging from mild acetabular dysplasia to frank dislocation. It affects approximately 1–2 per 1,000 live births, and is more common in girls, first-borns, breech presentations, and those with a family history. All newborns in the UK are examined for hip instability using the Barlow and Ortolani tests. High-risk infants are also offered hip ultrasound. When caught early and treated with a Pavlik harness, outcomes are excellent. Undetected DDH can lead to abnormal gait, pain, and early hip osteoarthritis.
