Developmental Dysplasia of the Hip: What Is It and Why Does It Still Cause Problems in Adults?
Developmental dysplasia of the hip (DDH) means the hip socket is too shallow. It cannot cover the ball of the thighbone properly. Many adults were never diagnosed as children. This poor fit puts extra stress on the joint. It leads to pain, stiffness and early wear. A standing, weight-bearing scan shows how the hip copes under real load.
Key points
- DDH is a spectrum. It ranges from a mildly shallow socket to a fully dislocated hip.
- It is the most common structural cause of early hip arthritis in adults under 50.
- Lying-down scans can miss how DDH affects your alignment when you stand and bear weight.
- An EOS whole-body standing scan uses about 90% less radiation than a standard X-ray, around ten times less.
- ScanAlign provides the imaging that helps your surgeon or physiotherapist plan the right approach.
Developmental dysplasia of the hip is sometimes called congenital hip dislocation. But not every case involves a true dislocation. DDH sits on a spectrum. At one end, the socket is just a little shallow. At the other end, the ball of the thighbone sits partly or fully outside the socket. Many people go through childhood without clear symptoms. Then they develop hip pain, a limp or stiffness in their twenties, thirties or later.
The socket does not hold the ball as well as it should. So the cartilage wears unevenly, and the labrum (the ring of cartilage around the rim) takes extra strain. Over time this leads to osteoarthritis, often decades earlier than normally expected.
What are the symptoms of hip dysplasia in adults?
The most common symptom is a deep, aching pain in the groin or the front of the hip. It is often worse after walking, standing for a long time or exercise. You might also notice clicking, catching, or a feeling that the hip is unstable.
A deep ache that gets worse with activity and eases with rest.
You may tilt or lean to one side without realising it.
Difficulty crossing your legs, tying shoes or getting in and out of a car.
The hip may click or feel like it locks during certain movements.
Symptoms often develop slowly. Some people live with a stiff hip for years before seeking help. They assume it is just the way their body is built. Your body also compensates, so you may develop pain in your lower back, knee or other hip. This compensation pattern is one of the main reasons a whole-body view matters.
When is MRI more useful? EOS shows bones, joints and overall alignment. If your specialist suspects a labral tear, cartilage damage or other soft-tissue problems, MRI is usually the better tool. The two types of imaging often work well together.
What causes hip dysplasia?
DDH develops because the hip joint does not form properly during pregnancy or early infancy. The exact cause is not fully understood. But several factors raise the risk.
DDH tends to run in families, which suggests a genetic part.
Babies who sat bottom-down in the womb are more likely to develop DDH.
DDH is more common in first-born babies. It is several times more common in girls.
Many adults with DDH were simply never picked up by screening as babies. Screening programmes in the UK have improved over the decades, but milder cases still slip through. Perhaps you have always felt your hip was a bit stiff or clicky. If so, and especially if hip problems run in your family, it is worth looking into.
How does a standing EOS scan help with DDH?
A standing EOS scan captures your whole skeleton in one image while you are upright and bearing weight. This matters for DDH. It shows the true relationship between your hip socket, pelvis and spine under real-world load.
Standard hip imaging is usually taken lying down. When you lie flat, your muscles relax and the pelvis settles into a neutral position. The hip may then look less abnormal than it really is. Standing up changes everything. Gravity, muscle tension and your natural posture all come into play. This shows how the shallow socket really performs when you walk, stand and go about your day.
Your body is a connected chain from your feet to your head. If one hip socket is shallow, your pelvis tilts. Your spine curves to compensate. Your knee takes extra load on the other side. A scan of just the hip misses this chain reaction. An EOS whole-body image captures it all. It gives your surgeon or physiotherapist the complete picture they need.
Want to see how your hip alignment looks when you are standing and bearing weight?
Book a free video consultationThe EOS system uses about 90% less radiation than a standard X-ray, around ten times less. This is especially helpful if you need repeat scans over time to monitor the joint or plan surgery.
What can be done about hip dysplasia in adults?
Treatment depends on how shallow the socket is, how much wear has already happened, and what your symptoms are. ScanAlign is a diagnostic imaging clinic, so we do not provide treatment. But the imaging we produce helps specialists decide the right path for you.
For milder cases, physiotherapy that strengthens the muscles around the hip can help steady the joint and manage symptoms. For more significant dysplasia, surgical options may include a periacetabular osteotomy (a procedure to reposition the socket). If arthritis is already advanced, they may include hip replacement. Accurate alignment data from a standing scan is valuable for planning either approach.
Getting the right imaging early matters. The sooner the true shape and alignment of your hip is understood, the sooner the right specialist can advise you on managing it well. You may be living with hip pain, stiffness or a limp that has never been properly explained. If so, a whole-body standing assessment can be a useful starting point. Learn more about hip alignment and imaging on our hip page.
Before you start treatment, or change the one you are on, it is worth getting a detailed diagnosis. Knowing whether the cause sits in the pelvis, the legs or the spine changes what will actually help.
Frequently asked questions about DDH
Yes. Many adults with DDH were never picked up by screening as babies, especially milder cases. Symptoms often appear slowly in the twenties, thirties or later as the cartilage wears down.
Congenital hip dislocation is the older term. DDH is now preferred because it covers the full spectrum, from a mildly shallow socket to a fully dislocated hip. Not everyone with DDH has an actual dislocation.
An EOS scan captures your whole skeleton while you are standing. It shows the true alignment of your hip, pelvis and spine while you bear weight. A standard X-ray is usually taken lying down, which can make the hip look more normal than it is. Learn more about how EOS imaging works on the ScanAlign homepage.
EOS uses about 90% less radiation than a standard X-ray, around ten times less. Full details on safety and what to expect are on the FAQs page.
No. ScanAlign is a private, self-pay clinic. You can book directly without a referral. We start with a free video consultation to make sure the scan is right for your situation.
Yes. When the hip socket is shallow, the pelvis often tilts. This changes the loads through the spine and the other leg. Because of this compensation chain, pain can show up in the lower back, knee or other hip rather than the affected hip itself.
The price for patients travelling from abroad is confirmed during the free video consultation. You can read more on the FAQs page.
Not necessarily. The outcome depends on how severe the dysplasia is and how much cartilage damage has happened. Milder cases may be managed with physiotherapy and changes to activity. More significant dysplasia may require corrective surgery. Accurate imaging helps specialists plan the most suitable approach.
Yes. Surgeons planning a periacetabular osteotomy or hip replacement benefit from seeing the full alignment picture while you bear weight. The whole-body data helps them understand how the pelvis sits, how the spine compensates, and how the legs are loaded.
ScanAlign is at 19 Harley Street, London. The first step is a free video consultation, which you can join from home. We discuss your symptoms and check that an EOS scan is the right next step for you.
Understand your hip alignment
A free video consultation is the first step. We will discuss your symptoms and explain whether a standing whole-body scan is right for you.
Book a free video consultationSources
- NHS. Hip dysplasia. nhs.uk. Available at: https://www.nhs.uk/conditions/developmental-dysplasia-of-the-hip/
- Gala L, Clohisy JC, Beaulé PE. Hip Dysplasia in the Young Adult. Journal of Bone and Joint Surgery. 2016;98(1):63-73.
- International Hip Dysplasia Institute. Adult Hip Dysplasia. hipdysplasia.org.
Written by Abbas Dhami (Specialist Diagnostic Radiographer)
This page is general information and not a diagnosis.
ScanAlign is the trading name of CoreMed Solutions Ltd and operates under The Harley Street Hospital's CQC licence.