Periacetabular Osteotomy

What Is Hip Dysplasia?

Hip dysplasia is a condition where the acetabulum is too shallow or angled incorrectly, meaning it does not fully cover the femoral head.


As a result:

  • The hip joint becomes unstable
  • Pressure is unevenly distributed across the cartilage
  • The labrum (a ring of cartilage around the socket) is overloaded
  • Early wear and tear of the joint occurs


Hip dysplasia can be present from childhood or adolescence and may not cause symptoms until the teenage years or adulthood. Over time, untreated dysplasia can lead to chronic hip pain, labral tears, and early osteoarthritis.


What Is a Periacetabular Osteotomy (PAO)?

Periacetabular Osteotomy (PAO) is a hip preservation surgery designed to treat symptomatic hip dysplasia.


The goal of PAO is to reposition the acetabulum to better cover the femoral head, thereby improving joint stability and reducing abnormal stress on the cartilage and labrum.


Rather than replacing the hip joint, PAO preserves the patient’s natural hip, making it particularly suitable for younger and active individuals.


Who Is Suitable for a Periacetabular Osteotomy?

PAO is most commonly recommended for:

  • Young adults and adolescents with symptomatic hip dysplasia
  • Patients with hip pain that limits daily or sporting activities
  • Individuals with minimal to moderate arthritis
  • Patients with good hip joint cartilage quality
  • Those who wish to preserve their natural hip joint


PAO is less suitable for patients with advanced hip arthritis, significant cartilage loss, or stiffness that limits joint movement.


When Is PAO Not Recommended?

PAO is generally not recommended when:

  • Advanced hip osteoarthritis is present
  • There is significant cartilage loss
  • Hip motion is severely restricted
  • Pain is not related to dysplasia
  • The patient cannot commit to rehabilitation


In these cases, alternative treatments may provide better outcomes.


What Conditions Can a PAO Treat?

PAO is most commonly used to treat:

  • Developmental Dysplasia of the Hip (DDH)
  • Acetabular under-coverage
  • Hip instability related to dysplasia
  • Recurrent labral tears caused by poor socket coverage


In some cases, PAO may be combined with other procedures, such as labral repair or femoral osteotomy, depending on the individual hip anatomy.


What Are the Benefits of Periacetabular Osteotomy?

The potential benefits of PAO include:

  • Improved hip joint stability
  • Reduction in hip and groin pain
  • Better function during walking, sitting, and activity
  • Protection of cartilage and labrum
  • Slowing or preventing early arthritis
  • Preserving the natural hip joint
  • Delaying or avoiding hip replacement surgery


Many patients experience significant improvement in pain and quality of life after recovery.


What Are the Limitations of PAO?

While PAO can be highly effective, it is important to understand its limitations:

  • Recovery takes time and commitment
  • Pain relief may be gradual rather than immediate
  • It does not reverse existing severe arthritis
  • Outcomes depend on cartilage health and surgical precision


Careful patient selection is essential for the best results.


Non-Surgical Alternatives to PAO

Before surgery, some patients may try non-surgical options such as:

  • Activity modification
  • Physiotherapy to strengthen hip muscles
  • Anti-inflammatory medications
  • Pain-relief strategies
  • Image-guided injections


These options may reduce symptoms but do not correct the underlying bone structure.


What to Expect Before Periacetabular Osteotomy?

Before surgery, patients usually undergo:

  • Detailed clinical assessment
  • X-rays and advanced imaging (CT or MRI)
  • Hip motion and stability evaluation
  • Pre-operative planning of bone cuts
  • Medical clearance and anaesthetic review


Patients are educated about the procedure, recovery timeline, and rehabilitation requirements.


What Happens During a Periacetabular Osteotomy?

During surgery:

  • The procedure is performed under general anaesthesia
  • Bone cuts are made around the acetabulum
  • The socket is repositioned for optimal coverage
  • The new position is fixed with screws
  • Surrounding muscles and tissues are protected


The operation typically takes several hours and requires careful surgical expertise.


What to Expect After Periacetabular Osteotomy?

After surgery:

  • Hospital stay usually lasts several days
  • Pain is managed with medications
  • Weight-bearing is limited initially
  • Crutches or a walker are required
  • Physiotherapy begins early


Bone healing takes time, and activity is gradually increased under guidance.


Periacetabular Osteotomy Recovery and Rehabilitation

Recovery is gradual and structured:

  • Early phase focuses on pain control and mobility
  • Partial weight-bearing progresses over weeks
  • Strength and flexibility exercises increase gradually
  • Return to daily activities occurs over months
  • Return to sport may take 6–12 months


Commitment to rehabilitation is critical for success.


Periacetabular Osteotomy Prognosis

When performed for the right indications, PAO has excellent long-term outcomes.


Many patients experience:

  • Lasting pain relief
  • Improved function
  • Slower progression of arthritis
  • Long-term preservation of the natural hip


Outcomes are best when surgery is performed before significant joint damage occurs.


Periacetabular Osteotomy Risks

As with any major surgery, risks include:

  • Infection
  • Blood clots
  • Nerve or blood vessel injury
  • Delayed bone healing
  • Residual pain or stiffness
  • Need for further surgery


Careful surgical technique and rehabilitation reduce these risks.


What If Periacetabular Osteotomy Is Delayed?

Delaying PAO may result in:

  • Progressive cartilage damage
  • Worsening labral tears
  • Increased pain and instability
  • Development of early hip arthritis
  • Reduced suitability for hip preservation surgery


Early assessment allows for more treatment options and better outcomes.