Hip Dysplasia Surgery in Sydney
Hip dysplasia means the socket does not fully cover the ball of the hip, which overloads the joint and can lead to pain, labral tears and early arthritis. Treatment aims to improve hip stability, reduce symptoms and protect the joint for the long term.
What is hip dysplasia?
Hip dysplasia means the socket of the hip joint is too shallow or not shaped well enough to fully support the ball of the hip. In babies and young children, this is often called developmental dysplasia of the hip, or DDH.
In a well-formed hip, the ball sits centred inside the socket so the joint can grow and move normally. In dysplasia, the socket may be shallow and saucer-like, which makes the ball less stable. If the ball is not centred properly, normal growth and development of the hip can be affected.
When dysplasia persists into adolescence or adulthood, the shallow socket means the cartilage, labrum and surrounding muscles take on extra load. Over time, this can lead to groin pain, muscle fatigue, labral tears, instability and early arthritis.
Do you need hip dysplasia surgery?
Not every child or adult with hip dysplasia needs surgery. Mild or borderline cases may be monitored, treated with bracing in infancy, or managed with physiotherapy and activity modification in selected adults.
Surgery is usually considered when the hip is unstable, dislocated, not developing properly despite bracing, or when an adolescent or adult has painful dysplasia that is overloading the labrum and cartilage. In adults, the decision also depends on whether enough healthy cartilage remains for joint-preserving surgery to be worthwhile.
The aim is a centred, stable hip. Whether treatment is observation, bracing or surgery, the goal is to keep the ball well positioned in the socket so the hip can grow, move and carry load as normally as possible.
For adults and adolescents, one of the main surgical options is periacetabular osteotomy, or PAO. This is a joint-preserving operation that reorients the socket so it gives better coverage to the ball. If arthritis is already advanced, total hip replacement may be more appropriate than PAO.
What causes hip dysplasia?
Developmental dysplasia of the hip is usually caused by a combination of genetic, mechanical and environmental factors. The exact cause is not always known, but some factors are known to increase risk.
Risk factors for DDH
- Family history: having a close family member with DDH increases risk
- Breech position: babies positioned bottom or feet first during pregnancy are at higher risk
- Foetal packaging: reduced room in the uterus, such as first pregnancy, twins or low amniotic fluid, may contribute
- Sex: DDH is more common in female infants
- Side: the left hip is commonly affected
- Swaddling position: tight swaddling with the legs held straight may increase risk in susceptible babies
Having a risk factor does not mean a child will definitely have DDH, and some children with DDH have no obvious risk factors. This is why newborn and infant hip checks are important.
What might a parent or patient notice?
Infant hip dysplasia can be clinically silent. Many babies with milder dysplasia have no pain, normal movement and normal development through early childhood, especially when the hip is not dislocated.
If the socket remains shallow into adulthood, symptoms may appear later. This may be in the teenage years, young adulthood, middle age or older age depending on the severity of dysplasia, cartilage health and activity demands.
Possible signs in babies
- One leg appearing shorter than the other
- Uneven skin folds on the thighs or buttocks
- Reduced ability for one hip to move out to the side in the frog-leg position
- A clunk or feeling of the hip moving in and out when changing a nappy
- One leg turning or resting differently compared with the other
Possible signs in older children
- An asymmetric limp or waddling gait
- Leg length difference
- Reduced hip abduction
- Increased arch in the lower back, especially if both hips are affected
- Difficulty with running, stairs or longer walking as symptoms develop
Possible symptoms in adolescents and adults
- Groin pain or deep hip pain
- Hip muscle fatigue with standing or walking
- Pain with squatting, twisting or activities that combine hip flexion and rotation
- Clicking, catching, locking or giving way from labral overload
- Progressive stiffness or reduced walking tolerance if arthritis develops
How is hip dysplasia diagnosed?
Hip dysplasia is diagnosed with a combination of physical examination and imaging. The right test depends on age, symptoms and whether the hip is still mostly cartilage or has developed enough bone to be assessed on X-ray.
A doctor or health practitioner will examine the hips, legs and pelvis for asymmetry, limited range of motion, instability, limp or differences in leg length. In babies, the examination may include manoeuvres that assess whether the hip is unstable or dislocated.
Ultrasound in infants
Ultrasound is particularly useful in young infants because much of the hip is still cartilage and cannot be seen clearly on X-ray. It can assess how much of the femoral head is covered by the socket, the shape and steepness of the socket roof, and whether the hip remains stable when gentle stress is applied.
Common ultrasound measures include femoral head coverage and the alpha angle. In a mature and stable hip, the socket should give good coverage and the bony roof should not be excessively steep. Results need to be interpreted based on the child’s age and clinical findings.
X-rays in older infants, children and adults
From around six months of age, X-rays become more useful because the bones are more visible. X-rays can show the acetabular index, femoral head position, asymmetry of the ossific nuclei and whether the ball is subluxed or dislocated.
In adults, standing pelvis and specialised hip views help assess socket coverage, joint congruence, cartilage space, labral overload signs and whether hip preservation surgery is realistic. MRI or CT may also be used when more detail is needed.
DDH is not always easy to diagnose, and some cases need repeated examinations and imaging over time. Once diagnosed, treatment is tailored to age, severity, symptoms, stability and joint health.
What are the treatment options?
Treatment for hip dysplasia depends on the age of the patient and the severity of the condition. The aim is always to obtain and maintain a well-centred hip joint so the ball and socket can develop or function as normally as possible.
Observation
In some mild or borderline cases, especially in very young infants with stable hips, observation and repeat imaging may be appropriate. This is only suitable when the treating doctor is confident the hip is stable and safe to monitor.
Bracing
A brace such as a Pavlik harness may be used in infants to hold the hip in a position that encourages the ball to sit deeply in the socket. This helps guide socket development while still allowing the baby to move their legs. In older babies, other braces such as a Rhino brace may be used depending on age and stability.
Surgery in infants and children
Surgery is generally reserved for more severe cases, older babies, dislocated hips or hips that do not respond to bracing. The operation may involve physically repositioning the ball into the socket and supporting the hip in a spica cast while it stabilises and heals.
Surgery in adolescents and adults
In adolescents and adults with painful dysplasia but enough cartilage remaining, hip preservation surgery may be considered. The most common option is periacetabular osteotomy, or PAO, which reorients the socket to improve coverage of the femoral head. PAO is designed to reduce overload and delay or prevent progression to arthritis in suitable patients.
If the hip already has advanced arthritis, hip replacement is usually more reliable than hip preservation surgery. This is why early diagnosis and careful imaging are important.
Benefits and risks
What treatment can aim to achieve
- Keep the ball centred in the socket during growth
- Improve socket development in infants where possible
- Reduce instability and abnormal loading
- Relieve pain caused by overload of the labrum and cartilage
- Improve walking, standing tolerance and hip function
- Protect the hip joint and reduce the risk of early arthritis in suitable cases
- Delay or avoid hip replacement where joint preservation is realistic
Risks to understand
- Observation: the hip may not improve and may need bracing or surgery later
- Bracing: skin irritation, fit issues, femoral nerve irritation, failure to hold the hip centred, or rarely avascular necrosis
- Infant surgery: infection, stiffness, recurrent instability, avascular necrosis, need for further surgery and cast-related issues
- PAO surgery: bleeding, blood clots, nerve irritation, non-union, hardware irritation, residual pain, stiffness and ongoing arthritis progression
- Hip replacement: infection, blood clots, dislocation, leg length difference, implant wear or loosening and future revision surgery
All treatment decisions are individual. The goal is to choose the option that gives the hip the best chance of stable development or long-term function while avoiding unnecessary treatment.
Infant vs adult hip dysplasia
Infant DDH is about helping a developing hip become centred and stable while growth is still occurring. Treatment may involve observation, bracing or surgery depending on age and severity.
Adult hip dysplasia is different. The hip is fully developed, so treatment focuses on symptoms, socket coverage, labral overload, cartilage health and whether the natural joint can still be preserved.
| Infant DDH | Adult hip dysplasia |
|---|---|
| Usually detected through screening, risk factors or baby hip checks | Often presents with groin pain, fatigue, limp, labral tear symptoms or early arthritis |
| Ultrasound is commonly used in younger infants | X-rays, MRI and sometimes CT are used to assess structure and joint health |
| Treatment may include observation, Pavlik harness, other bracing or surgery | Treatment may include physiotherapy, PAO, hip arthroscopy in selected cases or hip replacement |
| The goal is to guide normal growth of the hip | The goal is to reduce overload, relieve pain and preserve the joint if possible |
| Early diagnosis can reduce long-term problems | Early assessment can help identify whether joint preservation is still realistic |
Periacetabular osteotomy for adult hip dysplasia
Periacetabular osteotomy, or PAO, is a hip preservation operation used for selected adolescents and adults with symptomatic hip dysplasia. It involves cutting around the acetabulum so the socket can be repositioned to better cover the ball of the hip.
PAO may be considered when the hip is painful, the socket is too shallow, the joint is still congruent and there is enough healthy cartilage remaining. It is not usually recommended once arthritis is advanced, because reshaping the socket cannot reliably fix a joint surface that is already badly worn.
Because PAO is a significant operation, preparation and rehabilitation matter. Recovery usually involves a hospital stay, protected weight-bearing with crutches, gradual strengthening and a long-term plan to rebuild hip and trunk control.
Preparing for hip dysplasia surgery
Preparation depends on the type of treatment being planned. For infants, preparation is usually about education, brace fitting, skin care and parent support. For surgery, preparation includes imaging, anaesthetic review, medical checks and clear instructions about hospital care.
For adolescents and adults, preparation often includes strengthening, gait assessment, hip and trunk control work, medication review, imaging and planning around home support, work, study, transport and stairs.
Your preparation may include
- Pelvis and hip X-rays
- Ultrasound in infants where appropriate
- MRI or CT where more detailed joint or bony planning is needed
- Medical and anaesthetic review
- Medication planning, especially blood thinners or medicines affecting bleeding risk
- Pre-operative physiotherapy and exercise physiology for older patients
- Planning for crutches, stairs, transport, school, work and home support
The procedure: what happens
The procedure depends on age and severity. In infants, treatment may involve bracing rather than surgery. If surgery is required, the surgeon may reposition the hip into the socket and use a spica cast to keep it stable while healing occurs.
In adolescents and adults having PAO, the surgeon makes controlled cuts around the socket so it can be reoriented into a better position. The repositioned socket is fixed with screws while the bone heals. The aim is to improve coverage, reduce overload and keep the natural hip joint working for as long as possible.
If arthritis is advanced, hip replacement may be discussed instead. In this operation, the damaged socket and ball are replaced with prosthetic components. This is usually the more reliable option when the joint surface is too worn for preservation surgery.
After surgery
After surgery, you or your child will be monitored in recovery before returning to the ward. Pain control, circulation, wound care, mobility and comfort are checked closely.
After infant surgery, cast care and safe handling are major parts of recovery. After PAO, protected weight-bearing with crutches is usually required while the bone heals. After hip replacement, patients are usually encouraged to stand and walk early with physiotherapy support.
When to seek help. Contact us or seek urgent care if there is fever, increasing wound redness, discharge, worsening calf pain or swelling, shortness of breath, chest pain, severe uncontrolled pain, new weakness, cast concerns, skin pressure areas or a sudden change in walking or limb position. Concerned about recovery? Call (02) 9437 9794.
Hip dysplasia surgery recovery and rehabilitation
Recovery depends on the treatment used. A baby in a brace needs regular review to check hip position, brace fit, skin condition and progress on imaging. A child in a spica cast needs careful skin, toileting, transport and positioning support.
Adolescents and adults recovering from PAO need a longer rehabilitation plan. The early phase is focused on bone healing, protected weight-bearing, pain control and safe movement. Strength, walking quality and activity tolerance are then rebuilt gradually.
Adult PAO recovery timeline
| Phase | Timeframe | What to expect |
|---|---|---|
| Protect & settle | Weeks 0–2 | Hospital recovery, wound care, pain control, protected weight-bearing and safe transfers |
| Protected mobility | Weeks 2–8 | Crutches, gentle exercises, avoiding overload and allowing bone healing |
| Weight-bearing progression | Weeks 8–12 | Gradual increase in loading if imaging and symptoms allow |
| Strength & control | Months 3–6 | Progressive hip, trunk and lower-limb strengthening, balance and gait retraining |
| Return to activity | Months 6–12 | Gradual return to higher-level exercise, sport-specific work or physical work as appropriate |
Timeframes vary depending on the procedure, healing, imaging, symptoms and your surgeon’s protocol.
Rehabilitation at MTP Health
This is where MTP Health is different. Your rehabilitation is delivered by our own physiotherapists and exercise physiologists, working in the same clinic as your surgeon. Your plan can begin before surgery and continue afterwards, with everyone working from the same goals and shared clinical record.
Rehabilitation may focus on hip strength, trunk control, walking quality, gradual loading, return to study or work, and eventually sport or higher-demand activity. Your recovery may be supported by our pre-operative rehabilitation, post-operative rehabilitation, physiotherapy and exercise physiology services.
Returning to driving, work and sport
Return to driving after hip dysplasia surgery depends on the operation, side, weight-bearing restrictions, pain, reaction time and whether you are taking strong pain medication. You should check with your surgeon and insurer before driving.
Desk-based work or study may be possible earlier than physical work, but sitting tolerance, transport and crutch use need to be considered. Physical work, running and sport usually require a longer staged plan and should be guided by your surgical and rehabilitation team.
Joint preservation takes time. Surgery can improve hip mechanics, but the result depends on healing, strength, movement control and sensible progression. The goal is not just to get through surgery — it is to build a hip that can carry load well over the long term.
Hip dysplasia surgery cost in Sydney
The cost of hip dysplasia surgery depends on the procedure, private health cover, hospital insurance, surgeon fees, anaesthetist fees, assistant fees, imaging, implants or screws, hospital stay and any excess on your policy.
If you are having surgery using private health cover, your out-of-pocket costs depend on your insurer, level of cover and whether reduced-gap arrangements apply. The anaesthetist is an independent practitioner and may charge a separate gap, so we provide their details and recommend checking their quote before surgery.
The surgeons at MTP Health participate in various reduced-gap schemes run by different health insurance providers. Availability can vary, and reduced-gap surgical time slots may involve a longer wait. Your insurer may also charge an excess depending on your policy.
If surgery is performed through the public system, there is no out-of-pocket surgical cost, but waiting times can be long and depend on hospital access, urgency category and local availability.
Why have your hip dysplasia surgery at MTP Health
MTP Health brings together fellowship-trained orthopaedic surgeons, careful assessment, physiotherapy and exercise physiology in one clinic. That matters because hip dysplasia is not just a scan finding — it is a structural condition that affects load, movement, symptoms and long-term joint health.
Honest advice comes first. If observation or non-surgical care is appropriate, we will explain why. If joint-preserving surgery is realistic, we will talk through what it involves. If arthritis means hip replacement is the safer option, we will explain that clearly too.
Your surgeon
Dr Jonathan Negus
Dr Negus is a fellowship-trained hip and knee surgeon with a focus on hip preservation and joint replacement. He works alongside MTP Health's physiotherapy and exercise physiology team so your diagnosis, treatment and rehabilitation are managed as one plan.
View full profile →Frequently asked questions
What is hip dysplasia?
Infant hip dysplasia, also called developmental dysplasia of the hip or DDH, is a condition where the hip joint of a baby or young child is not properly formed.
In babies with DDH, the socket is shallower and more saucer-like, which makes the ball less stable. When the ball is not centred in the socket, normal growth and development of the hip can be affected.
If dysplasia persists into adulthood, the shallow socket can place extra strain on the cartilage, labrum and muscles around the hip. This can lead to pain, labral tears and arthritis over time.
DDH is most commonly diagnosed in the first few months of life and can be treated with observation, bracing or surgery. Early diagnosis and treatment help reduce the risk of long-term complications.
What causes hip dysplasia?
Developmental dysplasia of the hip is caused by a combination of genetic and environmental factors. The exact cause is not always fully understood.
Known risk factors include family history, breech position during pregnancy, reduced room in the uterus, first pregnancy, twin pregnancy, low amniotic fluid and female sex.
Some babies develop DDH without any obvious risk factors, which is why routine hip checks remain important.
What would a parent or patient feel or notice with this condition?
Infant hip dysplasia is often clinically silent. Children with milder dysplasia may have normal movement, normal function and no pain throughout childhood.
In more severe cases, parents may notice one leg appearing shorter, uneven thigh or buttock skin folds, reduced ability for one hip to move out to the side, or a clunk when changing a nappy.
Older children may have a limp, waddling gait, leg length difference or restricted hip movement. If both hips are dislocated, signs can be harder to notice because there may be no obvious asymmetry.
In adults, symptoms may include groin pain, deep hip pain, muscle fatigue, limping, catching, giving way or pain with squatting, twisting and prolonged walking.
How is hip dysplasia diagnosed?
Hip dysplasia is diagnosed through physical examination and imaging. A doctor or health practitioner will assess the hips, legs and pelvis for asymmetry, instability, restricted movement, limp or leg length difference.
Ultrasound is particularly useful in infants under six months because much of the hip is still cartilage. It can assess femoral head coverage, hip stability, socket shape and the alpha angle.
From around six months and older, X-rays become the main imaging test because the bones are more visible. X-rays can show the acetabular index, femoral head position, asymmetry and whether the hip is subluxed or dislocated.
Some cases require repeated examination and imaging over time. Once diagnosed, treatment depends on age, severity, stability and joint health.
What are the treatment options?
Treatment depends on the age of the child or patient and the severity of the dysplasia. The goal is to obtain and maintain a well-centred hip joint so the ball and socket can grow or function properly.
In mild or borderline infant cases, observation and repeat imaging may be recommended. Bracing, such as a Pavlik harness, may be used to hold the hip in a position that encourages normal socket development. In older babies, other braces such as a Rhino brace may be used.
Surgery is usually reserved for more severe cases, older babies, dislocated hips or hips that do not respond to non-surgical treatment. After some infant surgeries, a spica cast may be needed for around eight to 12 weeks.
In adolescents and adults, options may include physiotherapy, hip arthroscopy in selected cases, periacetabular osteotomy to reorient the socket, or hip replacement if arthritis is advanced.
Can adults have hip dysplasia?
Yes. Some people are treated for hip dysplasia as babies and still have symptoms later, while others are not diagnosed until adolescence or adulthood.
Adult hip dysplasia may cause groin pain, fatigue, limping, labral tears, instability or early arthritis. Treatment depends on symptoms, socket coverage, cartilage health and whether the natural joint can still be preserved.
What is PAO surgery?
PAO stands for periacetabular osteotomy. It is a joint-preserving operation used for selected adolescents and adults with painful hip dysplasia.
The surgeon makes controlled cuts around the hip socket and repositions it to provide better coverage of the femoral head. The aim is to reduce overload, improve stability and protect the natural hip joint for as long as possible.
PAO is usually considered when there is enough healthy cartilage remaining. If arthritis is advanced, hip replacement may be more appropriate.
What happens if hip dysplasia is left untreated?
Untreated hip dysplasia can increase load on the labrum and cartilage because the socket does not fully support the ball of the hip.
Over time, this may lead to labral tears, pain, instability, limping and early osteoarthritis. The risk depends on how severe the dysplasia is and how well the hip remains centred and functioning.
Hip dysplasia consultations across Sydney
North Shore Health Hub, Level 4, Suite 401, 7 Westbourne St, St Leonards NSW 2065
St Leonards consulting →173 Warringah Road, Beacon Hill NSW 2100 — serving the Northern Beaches
Beacon Hill consulting →Also consulting at Gosford, Wahroonga, Castle Towers and Tamworth.
Talk to a surgeon about hip dysplasia
Book a consultation to understand the severity of the dysplasia, whether the hip can be preserved, and which treatment pathway is most suitable.
Book a ConsultationPrefer to talk? Call (02) 9437 9794 · GP & physio referrals: referrer information
- Current clinical guidance on developmental dysplasia of the hip, infant diagnosis, ultrasound, X-ray assessment, bracing and surgical treatment pathways.
- Current peer-reviewed literature and consensus guidance on adult hip dysplasia, periacetabular osteotomy, hip preservation surgery and hip replacement when arthritis is advanced.