How Is Hip Dysplasia Diagnosed in Adults? Signs, Imaging, and Assessment

Key Takeaways

• Adult hip dysplasia is diagnosed by combining symptoms, physical examination and properly performed imaging rather than relying on one scan or measurement.
• Standing pelvic X-rays assess socket coverage, alignment and arthritis, while MRI and CT may provide further information about the labrum, cartilage and three-dimensional anatomy.
• Borderline measurements require careful interpretation because hips with similar X-ray findings may differ substantially in stability and symptoms.
• A diagnosis does not automatically mean surgery; treatment depends on symptoms, joint stability, cartilage condition, functional limitations and response to rehabilitation.

Many adults living with hip dysplasia have no idea it was ever there. There was no childhood diagnosis, no early treatment, and no reason to suspect anything was different about their hip — until groin pain, fatigue with walking, or a sense of instability started showing up, often years into adult life. Getting to the bottom of this can feel confusing, particularly when an MRI report focuses on a labral tear without mentioning the underlying joint shape at all.

Adult hip dysplasia is diagnosed by combining the patient’s symptom pattern, a thorough physical examination, and properly performed imaging. X-rays usually provide the first assessment of socket coverage and alignment, while MRI and CT may be used to evaluate soft-tissue damage, three-dimensional anatomy and surgical suitability where relevant. No single scan or measurement tells the whole story — this article explains how the pieces actually fit together.

What is adult hip dysplasia?

Adult hip dysplasia describes a hip socket, or acetabulum, that is shallower or oriented differently than usual, providing less coverage of the femoral head than it should. This reduced coverage concentrates joint forces over a smaller surface area, which can increase stress on the labrum and articular cartilage and, in some patients, lead to a degree of instability.

It is important to separate structural dysplasia — the underlying shape of the joint — from symptomatic dysplasia, which refers to a dysplastic hip that is actually causing pain or functional problems. Not every dysplastic hip becomes symptomatic, and the presence of undercoverage on a scan does not automatically explain a patient’s symptoms.

Why can hip dysplasia go undiagnosed until adulthood?

It is more common than many people expect for dysplasia to remain unrecognised well into adult life. Several factors contribute to this.

• Childhood abnormality may have been mild enough to go unnoticed on screening
• There may be no known history of childhood hip treatment at all
• Symptoms often develop gradually rather than appearing suddenly
• High activity levels in adulthood can be the first thing to expose the underlying issue
• Pain is frequently misattributed to a muscle strain or tendon problem
• Imaging reports often focus on the labrum rather than commenting on the underlying socket coverage
• Symptoms may appear in the lateral hip, buttock or thigh rather than the more classically expected groin area

What are the signs of hip dysplasia in adults?

Symptoms of adult hip dysplasia can be varied, and no single symptom confirms the diagnosis on its own. Recognising the overall pattern is more useful than fixating on any one feature.

Groin pain

Groin pain is a common presenting symptom, though it is shared with many other hip conditions and is not specific to dysplasia.

Lateral hip or buttock pain

Some patients experience pain more toward the side or back of the hip, which can overlap with gluteal tendon problems.

Fatigue after walking or standing

A sense of the hip “tiring out” or aching after sustained activity can reflect the muscles working harder to stabilise an undercovered joint.

Clicking or catching

These sensations can relate to labral pathology, but are common in many hip conditions and are not diagnostic in isolation.

Instability or giving-way sensations

A feeling that the hip might give way, particularly in certain positions, can be a more specific clue to underlying instability.

Reduced activity tolerance

Gradually reduced tolerance for walking distances, standing, or higher-demand activities is a common pattern.

Muscle and tendon pain

Overload of the hip abductors, iliopsoas or other surrounding muscles is common as they work to compensate for reduced bony stability.

Symptoms with running, dancing, or a change of direction

Higher-demand movements that load the hip through greater ranges of motion often provoke symptoms earlier than everyday activity.

Who may be more likely to have adult dysplasia?

Certain factors increase the likelihood of underlying dysplasia, though none of them confirm the diagnosis by themselves — they simply raise clinical suspicion and support further assessment.

• A history of childhood hip dysplasia or treatment
• A breech presentation at birth
• A family history of hip dysplasia
• Being female, as dysplasia is more commonly recognised in women
• Generalised joint hypermobility
• Participation in high-flexibility sports such as dance or gymnastics
• Previous hip surgery
• Longstanding labral symptoms without a clear structural explanation

What happens during the clinical assessment?

A proper diagnostic assessment draws on several sources of information, not just an imaging report. Each part plays a distinct role in building the overall picture.

Medical and childhood history

The clinician asks about any known childhood hip issues, birth history, family history and previous treatment.

Pain pattern and activity triggers

Understanding exactly which activities provoke symptoms and how the pain has evolved, helps narrow down the likely source.

Gait assessment

Watching how a patient walks can reveal compensatory patterns or muscle weakness related to instability.

Hip range of motion

Assessing the available range of motion, including any excessive range that might suggest laxity, is a routine part of examination.

Strength and muscle-fatigue testing

Testing hip abductor and other muscle groups can reveal fatigue or weakness related to chronic joint understabilisation.

FADIR and other intra-articular tests

Provocative tests can reproduce intra-articular pain, though they are not specific to dysplasia and must be interpreted alongside other findings.

Instability or apprehension testing

Specific manoeuvres may reproduce a sense of apprehension or instability in certain hip positions, supporting a diagnosis of microinstability.

Hypermobility assessment and Beighton score

A simple screening tool, the Beighton score, assesses generalised joint laxity, which can contribute to the clinical picture without being diagnostic of hip instability on its own.

Assessment of the lumbar spine, pelvis, and tendons

Because several other structures can mimic or contribute to hip symptoms, a broader assessment of the lower back, pelvis and surrounding tendons is an important part of a thorough review.

What imaging is used to diagnose adult hip dysplasia?

Imaging plays a central role in confirming or excluding dysplasia, but different scans answer different questions, and the sequence usually starts with a well-performed X-ray.

Pelvic and hip X-rays

A standing, correctly positioned pelvic X-ray is usually the first and most important investigation. Positioning matters considerably here — pelvic tilt or rotation during the X-ray can distort the measurements that follow, so a technically adequate film is essential before any interpretation takes place.

Lateral centre-edge angle

This measurement estimates how much of the femoral head is covered by the acetabulum from the side. It is one of the most commonly used measurements, but its value depends heavily on the measurement method and should never be interpreted in isolation from the rest of the clinical picture.

Tönnis angle

Also known as acetabular inclination, this measurement assesses the slope of the weight-bearing roof of the socket. A steeper slope can support a diagnosis of inadequate coverage.

Anterior and posterior coverage

Lateral coverage alone does not tell the whole story — additional views or cross-sectional imaging may be needed to assess whether the front or back of the femoral head is adequately covered, since undercoverage can be more pronounced in one direction.

Joint-space and arthritis assessment

The X-ray is also used to check joint space, osteophytes and subchondral changes, since the health of the cartilage strongly influences which treatment options remain appropriate.

MRI or MR arthrogram

MRI, sometimes combined with a contrast injection, assesses the labrum and articular cartilage in detail, helping identify associated soft-tissue damage.

CT scan

Where more detailed surgical planning is needed, CT can provide three-dimensional information about socket orientation, acetabular version and femoral torsion that plain X-rays cannot capture.

What does borderline hip dysplasia mean?

This is one of the more genuinely confusing areas for patients, and it deserves a careful explanation rather than a simplified answer.

• Borderline dysplasia refers to hips with measurements that sit near commonly used thresholds between normal and dysplastic
• There is no single, universally agreed-upon definition of where this category begins and ends
• Two patients with an identical lateral centre-edge angle can have very different degrees of joint stability
• Additional measurements, symptoms, and examination findings are needed to interpret a borderline result properly
• The central question is not simply whether a number falls into a borderline range, but whether the hip actually behaves as an unstable, undercovered joint in that particular patient
• Treatment can differ substantially between a stable hip with coexisting impingement and a genuinely unstable dysplastic hip, even when the imaging numbers look similar

Can an MRI diagnose hip dysplasia?

MRI is a valuable tool, but it is not designed to diagnose dysplasia on its own, and it is worth understanding why.

• MRI is well-suited to assessing labral tears, labral hypertrophy, cartilage damage, and other soft-tissue findings
• Standardised X-rays remain the primary tool for assessing acetabular coverage and alignment
• A labral tear seen on MRI may actually be a secondary finding, caused by underlying undercoverage rather than an isolated problem in its own right
• MRI can sometimes underestimate certain cartilage lesions, particularly delamination-type damage
• A relatively unremarkable MRI does not necessarily rule out structural instability, since MRI is not the primary tool for assessing bony coverage
• It is often worth having the original images reviewed by an experienced clinician, rather than relying solely on the written report

What else could be causing the symptoms?

Because hip and groin symptoms overlap across many conditions, a careful assessment needs to consider several alternative or coexisting explanations before settling on dysplasia as the primary diagnosis.

• Femoroacetabular impingement, including cam or pincer morphology
• Gluteal tendinopathy or greater trochanteric pain syndrome
• Iliopsoas-related pain or snapping
• Adductor-related groin pain
• Athletic pubalgia
• Hip osteoarthritis
• Referred pain from the lumbar spine
• Sacroiliac joint pain
• Femoral-neck stress injury
• Avascular necrosis of the femoral head
• Deep gluteal syndrome
• A broader hypermobility spectrum disorder

Does a diagnosis mean surgery is required?

No. Being told your hip shows dysplasia is not the same as being told you need surgery. The right course of action depends on your symptoms, the degree of structural undercoverage, joint stability, cartilage condition and your own goals.

• Mild or manageable symptoms may be appropriate to monitor rather than treat aggressively
• Rehabilitation and activity modification may adequately control symptoms for many patients
• Ongoing monitoring may be reasonable where the function remains acceptable
• Specialist joint-preservation assessment becomes more relevant when symptoms are persistent or significant
• Arthritis-related treatment becomes more relevant where degeneration is already advanced
• Shared decision-making between the patient and clinician should guide the ultimate choice

How is adult hip dysplasia managed without surgery?

Non-surgical management cannot reshape the socket, but it can meaningfully improve symptoms and function for many patients, particularly those with milder or more stable presentations.

• Education about the condition and what aggravates it
• Hip-abductor, hip-flexor and trunk strengthening to improve muscular support around the joint
• Neuromuscular and single-leg control training
• Gradual, structured activity progression rather than abrupt increases in load
• Deliberately avoiding painful end-range stretching, since excessive flexibility work can aggravate instability in some patients rather than help
• Symptom-guided exercise progression
• Medication or selected injections where clinically appropriate
• Regular follow-up if symptoms change over time

When may PAO or another operation be considered?

For a subset of patients, structural surgery may become a relevant part of the conversation. Periacetabular osteotomy (PAO) is a procedure that reorients the acetabulum to improve coverage of the femoral head, and is generally considered only after a thorough assessment.

• Persistent pain and functional disability despite a genuine trial of rehabilitation
• Meaningful structural undercoverage confirmed on imaging
• Preserved cartilage, since PAO is a joint-preserving procedure rather than a treatment for advanced arthritis
• Clinically significant instability affecting daily activity, work or sport
• An inadequate response to structured non-surgical care
• Patient goals, age and general health suited to a joint-preservation approach

It’s worth understanding that PAO, hip arthroscopy, and hip replacement address different problems. Hip arthroscopy alone generally does not correct significant acetabular undercoverage and may not be the right tool if dysplasia is the primary underlying issue. Hip replacement, by contrast, becomes more relevant where arthritis has already progressed to the point that joint-preserving surgery is unlikely to provide lasting benefit.

For patients with persistent symptoms, meaningful socket undercoverage and preserved joint cartilage, learning more about hip dysplasia surgery may help clarify how structural procedures are used to improve femoral-head coverage and joint stability. This is most relevant when rehabilitation has not provided enough relief and a specialist assessment suggests that the underlying anatomy, rather than an isolated labral tear, is the main driver of symptoms.

Patient scenarios

These examples illustrate how the same underlying finding can lead to quite different conclusions depending on the full clinical picture.

Young adult with gradual groin pain

Pain develops with walking, running and prolonged standing. X-rays show undercoverage, and examination identifies abductor fatigue along with signs of instability. MRI is used to further assess the labrum and cartilage.

Flexible dancer or gymnast

The patient has a notably large range of motion but develops groin pain and a sense of instability. Hypermobility and repeated end-range loading are considered alongside the degree of acetabular coverage.

Runner labelled with a labral tear

MRI identifies a labral tear, but properly performed pelvic X-rays reveal that the tear may actually be secondary to underlying dysplasia. The treatment discussion, therefore, extends well beyond isolated arthroscopy.

Active adult with lateral hip pain

Undercoverage is present on imaging, but examination shows that gluteal tendon pain is currently the dominant issue. Rehabilitation may initially focus on tendon loading and pelvic control rather than the underlying bony shape.

Older patient with established arthritis

Dysplasia is identified as the underlying structural cause, but significant joint-space loss and stiffness make reconstructive surgery less suitable. Arthritis management or replacement assessment may be a more relevant discussion.

Borderline imaging measurements

A patient’s lateral centre-edge angle sits near a commonly used threshold. Further clinical examination, specialised imaging views and possibly CT help determine whether the hip is genuinely stable or unstable.

The Australian referral and imaging pathway

Understanding the typical Australian pathway can help patients know what to expect and plan accordingly.

• Initial assessment by a GP, physiotherapist or sports physician
• Referral for an appropriately performed pelvic X-ray
• GP referral to an orthopaedic hip-preservation surgeon for a Medicare-rebated private consultation
• Specialist review of symptoms, examination findings and the original imaging
• Further MRI, MR arthrogram or CT where these would meaningfully change the diagnosis or surgical planning
• Structured physiotherapy or monitoring where appropriate
• Discussion of PAO, arthroscopy, combined treatment or hip replacement, only where clinically relevant to the individual case
• Private or public hospital pathways if surgery is ultimately selected

It is worth noting that Medicare rebates typically cover only part of the consultation or imaging cost, and private health insurance coverage varies between policies. Outpatient physiotherapy generally involves separate fees, and public hospital access depends on referral, eligibility and clinical prioritisation. Current rebate and cost information should be confirmed directly with Medicare, your insurer and your surgeon’s rooms.

Questions to ask after being told you have dysplasia

If dysplasia has come up as part of your assessment, these questions can help you understand exactly what it means for you.

• Is the dysplasia definitely causing my symptoms?
• Is my hip stable or unstable?
• Which measurements were abnormal, and by how much?
• Is the finding frank dysplasia or borderline?
• Is there also a labral tear or cartilage damage?
• How much arthritis, if any, is present?
• Do I also have coexisting femoroacetabular impingement?
• Would a CT scan add useful information in my case?
• Can I continue exercising safely?
• What should my physiotherapy focus on?
• What happens if I choose to simply monitor it?
• Would hip arthroscopy actually address the underlying problem?
• Am I a suitable candidate for PAO?
• What factors are likely to affect my long-term outlook?

Frequently Asked Questions (FAQs)

1. Can hip dysplasia first be diagnosed in adulthood, and can you have it without pain?

Yes to both. Some adults have no recognised childhood diagnosis and only develop symptoms later, when activity demands or cumulative tissue stress increase. Structural dysplasia and symptomatic dysplasia are not the same thing, so it is possible to have the underlying joint shape without significant pain, and treatment decisions depend on symptoms and function as well as imaging findings.

2. Is an X-ray enough to diagnose hip dysplasia?

X-rays usually provide the initial structural assessment and are an essential first step, but borderline or more complex cases often require MRI, CT and a detailed clinical examination before a confident diagnosis can be made.

3. What is the lateral centre-edge angle, and is there a normal value?

The lateral centre-edge angle is a commonly used X-ray measurement that estimates lateral coverage of the femoral head by the acetabulum. Reference thresholds vary depending on measurement technique and clinical context, so a single number should never be treated as an absolute diagnosis without considering the full clinical picture.

4. What is borderline hip dysplasia?

It describes hips with measurements that sit near commonly used thresholds between normal and dysplastic. Some borderline hips are genuinely stable, while others show clinically important instability — additional imaging, symptoms and examination findings are needed to tell the difference.

5. Does MRI show hip dysplasia, and can a labral tear be caused by it?

MRI can show soft-tissue effects such as labral tears, labral enlargement or cartilage damage, but standardised X-rays remain the primary tool for assessing acetabular coverage and alignment. Yes, a labral tear can be caused or aggravated by inadequate socket coverage, meaning the labrum may be a secondary victim rather than the primary problem — and this is why a labral tear alone does not automatically mean arthroscopy is the right treatment.

6. Does hypermobility mean I have hip dysplasia?

No. Generalised joint hypermobility may contribute to instability and is a relevant part of the overall clinical picture, but it does not by itself establish that the acetabulum is uncovering the femoral head.

7. Does a diagnosis automatically mean I need PAO surgery?

No. Surgery is considered based on symptoms, the severity of structural undercoverage, joint stability, cartilage condition, functional limitations, and how you have responded to non-surgical care — not simply because dysplasia has been identified on imaging.

The Bottom Line 

Diagnosing adult hip dysplasia is a process of putting several pieces of information together, not the result of a single measurement or scan. Your symptom pattern, a thorough physical examination, properly performed X-rays and, where needed, MRI or CT all contribute to understanding whether your hip is genuinely undercovered, unstable, and responsible for the symptoms you are experiencing. A diagnosis of dysplasia is the start of a conversation about the right path forward, not an automatic route to surgery.

If you have persistent groin, hip or buttock symptoms that haven’t been fully explained, or if you have been told you have a labral tear without a clear discussion of the underlying joint shape, it is worth seeking assessment from a clinician experienced in hip preservation to understand the complete picture.