Are You Missing Hip Dysplasia? Essential Clinical Clues for Physios

Hip dysplasia is an under-diagnosed and consequently mis-managed hip condition affecting people from a young age.

As physiotherapists are often the first point of contact for people seeking help for hip pain, it’s essential that we better understand the condition and how to identify it. By improving our ability to recognise hip dysplasia early, we can ensure people get the care they need, and help reduce the significant physical and mental burden that comes with delayed or incorrect diagnosis.

In this blog, I’ll outline some key factors to look out for during your subjective and objective assessment of patients with hip pain.

For a deep dive into assessment, diagnosis and management of hip dysplasia, be sure to check out the full Masterclass with expert physiotherapists Alesha Coonan and Dr Michael O’Brien HERE.

Background

Hip dysplasia symptoms can significantly impact participation in activities like sport and work. Patients with hip dysplasia are also at a higher risk of developing early-onset hip osteoarthritis (before age 50).

Research shows that around 32% of people presenting with hip pain have hip dysplasia. Yet on average, it takes patients 5 years of symptoms and 3 different clinicians to receive an accurate diagnosis. This delay not only worsens physical symptoms but can also add frustration and mental health challenges.

We as physios are well placed to change this trend by sharpening our diagnostic skills.

So, first – what is hip dysplasia? It’s an umbrella term describing a lack of congruency between the acetabulum and femoral head, caused by variations in shape, size, and/or orientation. The three most common types include:

• Anteversion = anteriorly rotated acetabulum or femoral head leading to undercoverage of the anterior aspect of the hip joint
• Retroversion = posteriorly rotated acetabulum or femoral head leading to undercoverage of the posterior aspect of the hip joint
• Global = femoral head undercovered by acetabulum all the way around

See Alesha explain these common types of hip dysplasia in the below video from her Masterclass:

Subjective assessment

The patient history offers valuable clues to whether hip pain may stem from dysplasia. Alesha highlights several key questions and risk factors to explore:

• Family history of ‘clicky hips’, total hip replacements etc.
• Was the patient a breech baby?
• Were they the first born, or are they a twin/triplet? (risk factors for hip dysplasia due to positioning in the womb)
• Positioning/alignment in childhood: would they sit in the W-sitting position? Were they pigeon or duck toed?
• Milestones: did they skip crawling and go straight to walking? Did they start walking late (>18 months old)?
• What sports did they do growing up (ballet, gymnastics, martial arts)?
• Presence of hypermobility (current or past)

These are all really useful clues which might raise your suspicion of hip dysplasia. Another important note is the aggravating factors, which can point toward the type of hip dysplasia:

1. Extension pattern (think anteverted): anterior hip pain when the leg is behind them (e.g., pain with walking, walking quickly), hip flexion stretches make pain worse, pain with prolonged standing and sitting (due to aggravated anterior structures).
2. Flexion pattern (think retroverted): pain with deep flexion (e.g., squats,deadlift, child’s pose), posterior hip pain can feel like cramping, pain in sitting, achiness through gluteals.

The subjective should help you identify whether hip dysplasia could be a source of your patient’s symptoms, and these clues can guide your objective assessment.

Objective assessment

Diagnosing hip dysplasia is rarely straightforward, and there’s no single clinical test that gives a definitive answer (contributing to under-diagnosis!).

Combining your thorough subjective assessment with an equally thorough clinical assessment is key. Be sure to check out the full Masterclass, where Michael provides a comprehensive description of the physical assessments he uses in clinic – below are some key assessments he routinely uses:

Posture and weight transfer: look for sway posture and excessive posterior pelvic tilt (common in extension pattern hip dysplasia). Assessing weight transfer into a single-leg stance provides valuable insight into control and informs treatment planning.

Gait analysis: patients often demonstrate reduced peak hip extension angle and moment, so keep an eye out when assessing the patient’s gait pattern!

Range of motion (ROM): standard clinical assessment of the hip should include ROM assessment to gauge functional deficits, and monitor change over time. A few clinical pearls specific to hip dysplasia that Michael points out are:

1. Drehmann sign: hip external rotation (ER) and abduction during hip flexion assessment – this can often be a sign of retroverted hip dysplasia.
2. Prone hip internal rotation (IR) and ER ROM assessment: femoral retroversion can result in increased ER ROM and decreased IR ROM, while femoral anteversion can result in an increased IR ROM and decreased ER ROM.

Watch Michael demonstrate how he assesses rotation in this short clip from his Masterclass:

Special tests: the Flexion-ADduction-Internal-Rotation (FADIR) provocation test is often associated with femoroacetabular impingement, but it’s important to note that a positive FADIR occurs in approximately 58% of people with hip dysplasia. The FADIR should not be used as a diagnostic test, but it is useful when trying to rule out the hip joint as a source of pain (i.e., if the patient does not report provocation of symptoms, it is less likely – but not impossible – the hip joint is the source of symptoms).

A few additional special tests for hip dysplasia Michael uses include:

• Hyperextension External Rotation (HEER) test = with the patient in supine and legs off the end of the bed, the hip is hyperextended and externally rotated. A positive test includes reproduction of pain and/or symptoms (e.g., clicking, apprehension).
• Abduction Hyperextension ER (AB-HEER) test = performed in sidelying, the clinician moves the patient’s hip into extension, abduction and ER while applying a posterior-anterior force through the hip, looking for reproduction of pain and/or symptoms (e.g., clicking, apprehension).

Strength testing: hip flexion, extension, abduction, adduction, IR and ER strength should be tested to gain an understanding of the patient’s function, and guide treatment planning.

By synthesising your objective findings with your subjective assessment, you can form a comprehensive clinical picture, identify potential indicators of hip dysplasia, and tailor an appropriate management plan.

Imaging considerations

For physios, the decision to refer for imaging can feel tricky. On the one hand, imaging risks over-medicalisation and catastrophisation. On the other, hip dysplasia is chronically under-diagnosed, and imaging can provide clarity that sets patients on the right management pathway.

Michael suggests considering:

• Patient trajectory: Are they already improving with some simple strategies? Or have symptoms persisted despite seeing other practitioners?
• Previous treatment and rehabilitation: multiple bouts of structured rehab with little progress may warrant imaging.
• Patient attitudes and beliefs: do they need a clear diagnosis for reassurance and motivation?
• Financial cost: imaging costs can vary widely depending on location and referrer.
• Your ability to interpret the findings: if you’re the sole practitioner treating this patient, you need to understand the findings to be able to translate them meaningfully to the patient.

If you decide the patient would benefit from imaging, it’s recommended that you start with radiographs. Watch Michael explain how to measure a common radiographic parameter – the Lateral Centre Edge Angle (LCEA) – in this clip from his Masterclass:

Wrapping up

Reducing the time it takes for patients with hip dysplasia to get the right care starts with physiotherapists being able to recognise it earlier.

By refining our subjective and objective assessment skills, we can better identify this under-diagnosed condition, and subsequently manage it more appropriately so we can work towards reducing the burden of hip-related pain in young and middle-aged adults.

If you want to know exactly how two hip experts manage hip dysplasia from start to finish, watch Alesha Coonan and Dr Michael O’Brien’s full Masterclass HERE. This is a must watch for any physios treating hip pain.