Acetabular hip dysplasia is a condition affecting the stability and mechanics of the hip joint. It occurs when the acetabulum, the socket part of the pelvis, does not develop deeply enough to adequately support the head of the femur. As a result, the hip joint has reduced stability and altered load distribution, which can lead to pain, functional limitation, and early joint degeneration.
Hip dysplasia can present at different stages of life. While some forms develop in infancy or childhood, acetabular hip dysplasia is often diagnosed during adolescence or adulthood when symptoms begin to interfere with daily activities. Physiotherapy for acetabular hip dysplasia focuses on improving muscular support, optimising joint loading, and reducing pain to delay or prevent progression.
Key Facts
Risk Factors
- Family history of hip dysplasia
- Breech birth position
- Female sex
- History of hip instability or clicky hips in childhood
Symptoms
- Groin pain or pain on the outside of the hip
- Limping or altered walking pattern
- Pain that worsens with activity and eases with rest
- Catching, snapping, or popping sensations in the hip
- Reduced hip range of motion
- Difficulty lying on the affected side
Aggravating Factors
- High-impact activities such as running or jumping
- Prolonged walking or standing
- Sleeping on the affected hip
Causes
Acetabular hip dysplasia occurs due to inadequate development of the acetabulum, resulting in insufficient coverage of the femoral head. This altered anatomy leads to increased joint stress and instability, particularly during weight-bearing activities.
Risk factors include a family history of hip dysplasia, being born in a breech position, female sex, and a history of “clicky” or unstable hips during infancy. Over time, abnormal joint mechanics can contribute to cartilage damage and labral injury.
How Is It Diagnosed?
Diagnosis is determined based on a thorough subjective and objective history. Imaging is used to quantify the degree of severity.
During your assessment, your physiotherapist may ask you questions such as whether you had a family history of hip dysplasia, if you were born in breached position, or if you had “clicky” hips as a child. From here, your physiotherapist will perform a physical examination where they will assess for hypermobility, hip range of motion, and evaluate your overall level of function.
Your physiotherapist or treating general practitioner may also request an X-Ray to evaluate the Lateral Centre Edge Angle (a line of best fit found on the radiograph running from the femur to the acetabulum.)
Although universal agreement has not been reached, these angles can be interpreted as follows:
- <24 degrees: Borderline acetabular dysplasia
- <18-20 degrees: Definite global acetabular dysplasia
In infants and children, radiographs can also be used to monitor hip joint development and maturation.
Investigations & Imaging
- X-ray
- Used to assess acetabular coverage and measure the lateral centre edge angle
- MRI
- Used to assess cartilage, labral integrity, and associated joint pathology
Grading / Classification
- Borderline dysplasia
- Lateral centre edge angle less than 24 degrees
- Definite acetabular dysplasia
- Lateral centre edge angle less than 18 to 20 degrees with reduced femoral head coverage
Physiotherapy Management
Physiotherapy is an important component of conservative management for acetabular hip dysplasia. The aim of physiotherapy is to improve muscular support around the hip, optimise joint control, and reduce excessive stress on the joint during daily and sporting activities.
Exercise
Exercise-based rehabilitation focuses on strengthening the muscles that stabilise the hip, particularly the hip extensors, abductors, and external rotators, as well as the deep abdominal muscles. These exercises help improve joint stability and reduce pain by improving load distribution through the hip.
Activity Modification
Activity modification is essential in managing acetabular hip dysplasia. Physiotherapists guide patients to avoid activities that place excessive stress on the hip, particularly high-impact or deep hip flexion movements, while maintaining overall physical activity.
Manual Therapy
Manual therapy may be used to address secondary stiffness or muscle tightness around the hip and pelvis, supporting improved movement and comfort.
Heat & Ice
Heat or ice may be recommended for short-term pain relief depending on symptom presentation and activity levels.
Education
Education is central to physiotherapy for acetabular hip dysplasia. Understanding joint mechanics, activity modification, and long-term joint care empowers patients to manage symptoms effectively.
Other
Physiotherapists also provide gait advice and may recommend walking aids in more symptomatic cases to offload the affected hip.
Other Treatments
Other management strategies may include short-term use of anti-inflammatory medication, weight management to reduce joint load, and participation in low-impact activities such as swimming, cycling, or Pilates.
Surgery
Surgical management may be considered if symptoms do not respond to conservative treatment or significantly impact daily function. Procedures aim to improve acetabular coverage and joint stability and are guided by orthopaedic assessment.
Prognosis & Return to Activity
The prognosis for acetabular hip dysplasia varies depending on severity and timing of diagnosis. With early physiotherapy management and appropriate activity modification, many individuals can manage symptoms effectively and delay progression to osteoarthritis.
Complications
- Early onset hip osteoarthritis
- Labral tears and cartilage damage
- Chronic hip pain and functional limitation
Preventing Recurrence
- Maintain hip and core strength to improve joint stability
- Avoid repetitive high-impact loading of the hip
- Seek early physiotherapy assessment for persistent hip pain
When to See a Physio
- Persistent hip or groin pain
- Limping or reduced tolerance to activity
- Hip pain with a history of childhood hip issues