Diagnosed late: hip dysplasia found after 6 months
Written by Dr. Mutasem Aldhoon, pediatric orthopedic consultant · Medically reviewed by the Baby Hip Center pediatric orthopedic team · Last reviewed September 1, 2026
A hip dysplasia diagnosis after six months usually means a closed reduction under anaesthetic and a spica cast rather than a harness, and the older the child the more likely surgery becomes. Late diagnosis genuinely happens despite good screening, and outcomes after treatment are still good — but the treatment is bigger, and time matters.
If you have just been told at eight or twelve months that your baby's hip is dislocated, the first thing most parents feel is guilt, and the second is anger that it was missed. Neither is warranted. Screening examinations are normal in a real proportion of hips that later prove dysplastic, and some hips genuinely deteriorate after a normal early scan.
Why screening misses cases
- A shallow but stable socket produces a completely normal Ortolani and Barlow examination.
- The examination becomes unreliable after about three months, as a dislocated hip becomes stiff rather than loose.
- Some hips are normal at six weeks and become dysplastic later — so-called late-developing dysplasia.
- Where scans are only offered to babies with risk factors, dysplasia in a baby with none is found clinically or not at all.
What treatment looks like now
| Age at diagnosis | Usual approach |
|---|---|
| 6-12 months | Closed reduction under anaesthetic and spica cast; sometimes traction beforehand |
| 12-18 months | Closed reduction if it will hold, otherwise open reduction |
| 18 months - 3 years | Open reduction, commonly with a pelvic and/or femoral osteotomy |
| Over 3 years | Open reduction with bone reshaping and sometimes femoral shortening |
The outlook
Most children treated between six and eighteen months walk normally, play sport and have no functional restriction. Two things need honest mention: the socket may remain slightly shallow and need watching or a further procedure during growth, and there is a small risk to the blood supply of the femoral head with any reduction, which is why teams reduce carefully and check with imaging afterwards.
Questions worth asking now
- Is the plan a closed or open reduction, and what decides between them on the day?
- Will an arthrogram or MRI be used to confirm the hip is seated?
- How long in the cast, how many cast changes, and what comes after — a brace?
- What follow-up X-rays are planned, and until what age?
- What is the specific concern about the blood supply in my child's case?
Ask for the images, not just the report
If you want an independent reading before consenting to surgery, request a copy of the X-rays on disc or through the hospital portal. A second opinion on the actual films is far more useful than a second opinion on a summary of them.
Want your own baby's images read by a consultant?
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Read next
- Signs of hip dysplasia in newborns and babies
Uneven thigh creases, one leg that seems shorter, limited spread on one side, and the later signs at crawling and walking age.
- Is hip dysplasia painful for babies?
Untreated hip dysplasia is almost never painful in infancy — which is exactly why it gets missed. When pain does appear, and what it means.
- How to get a second opinion on your baby's hips
What to bring, what to ask, and how to request a second opinion without damaging the relationship with your baby's own doctor.
This page is general information about developmental dysplasia of the hip, not a diagnosis of your own baby. It does not replace examination by your baby's doctor, and it is not for emergencies.