Developmental dysplasia of the hip

Also called DDH, Clicky hip, Hip dysplasia

A hip that has not formed properly in a baby. Caught early it is treated in a harness; caught late it needs surgery.

What it is

A condition present from birth in which the hip socket is too shallow, so the head of the thigh bone is unstable or dislocated.

It affects around 1 to 2 babies in every 100 to some degree. Risk factors are a breech position, particularly after 36 weeks, a family history in a first-degree relative, being a first-born girl, and being one of multiples.

All babies are examined at the newborn and six to eight week checks, and babies with risk factors are offered an ultrasound.

**Timing is everything.** Treated in the first few months with a Pavlik harness, which holds the hips in the right position while the socket forms, the great majority resolve completely with no surgery. Diagnosed after walking has started, it usually needs surgery, sometimes several operations, and carries a higher risk of early osteoarthritis and hip replacement in adulthood.

Late diagnosis remains a real problem: a proportion of cases are missed at the newborn checks, because early dislocation can be silent and painless.

**Swaddling with the legs straight and tightly wrapped increases the risk**, and hip-healthy swaddling, leaving the legs free to bend up and out, is the practical prevention. Baby carriers and slings should support the thighs in the same M-shaped position.

Signs you might notice

In a baby: a clicking or clunking hip on examination; uneven skin creases at the thigh or buttock; one leg appearing shorter; limited ability to spread one hip outwards when changing a nappy.

In a toddler: walking late; a limp; walking on tiptoe on one side; a waddling gait if both hips are affected.

Often no symptoms at all, and no pain, which is why the checks matter.

Get assessed: any asymmetry of leg length or skin creases; difficulty spreading the hips; a limp at any age; or late walking.

Ask specifically for an ultrasound if there was a breech presentation, a family history, or a twin pregnancy, and the baby has not had one.

In adults: hip pain in a young adult with a history of DDH, which may mean early arthritis and warrants assessment.

How it can affect day-to-day life

Nappy changing is the moment most parents would notice asymmetry, and knowing what to look for, creases, leg length and how far each hip spreads, turns that into screening.

The Pavlik harness is worn continuously for weeks and is daunting at first. Practical guidance on bathing, dressing, car seats and sleeping makes an enormous difference, and specialist nurses and parent groups are the best source.

Hip-healthy swaddling is a simple message that is not widely known: wrap the arms and chest if you wish, leave the hips and legs free to move.

Baby carriers should support the thighs so the knees are higher than the bottom; narrow-based carriers that leave the legs dangling are less hip-friendly.

Where surgery is needed, a hip spica cast for weeks is a major undertaking for a family, affecting car seats, nappies, sleeping and school.

Long-term follow-up continues into skeletal maturity, and adults with treated DDH should mention it if hip pain develops.

Supporting someone well

Ask for a hip ultrasound if there was breech presentation, a family history, or a multiple pregnancy.

Look at the hips at nappy changes: creases, leg length, and how far each hip spreads.

Get any limp, late walking or asymmetry assessed; do not wait.

Use hip-healthy swaddling: arms wrapped if you wish, legs free to bend up and out.

Choose a carrier or sling that supports the thighs with knees higher than the bottom.

Wear the harness exactly as instructed, and ask for practical help with bathing and dressing.

Keep the follow-up appointments through childhood.

Mention a history of DDH if hip pain develops in adulthood.

Where to get help

A GP practice, health visitor or the newborn and six-week checks.

Paediatric orthopaedics for ultrasound, harness treatment and surgery.

Steps Charity Worldwide support families with lower limb conditions including DDH.

Arthritis UK for adult hip problems following DDH.