Courtesy: Leandro Alves de Oliviera, Brazil

 

Total Hip Arthroplasty (THA) After Failed Hip Arthroscopy

Introduction

Hip arthroscopy has become a widely accepted procedure for the treatment of:

• Femoroacetabular impingement (FAI)
• Labral tears
• Chondral lesions
• Loose bodies
• Ligamentum teres pathology
• Snapping hip syndrome

Although hip arthroscopy is an important hip preservation procedure, some patients eventually progress to:

• Total Hip Arthroplasty (THA)

Conversion to THA is generally considered:

• Failure of hip preservation surgery

Understanding which patients are likely to fail arthroscopy is critical for appropriate patient selection and surgical planning.

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Common Indications for Hip Arthroscopy

Hip arthroscopy is commonly performed for:

• Femoroacetabular impingement (most common indication)
• Labral tears
• Chondral defects
• Loose bodies
• Ligamentum teres injuries
• Snapping hip disorders

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The Most Important Clinical Question

When Should Arthroscopy Be Avoided?

A key principle in hip preservation surgery is recognizing:

• Which patients are poor candidates for arthroscopy

In certain situations, patients may achieve better outcomes with:

• Primary Total Hip Arthroplasty

rather than undergoing unsuccessful hip preservation procedures.

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Poor Candidates for Hip Arthroscopy

Absolute and Relative Contraindications

Patients with the following features have poorer outcomes after arthroscopy:

• Joint space less than 2 mm
• Established osteoarthritis
• Tönnis grade 2 or higher
• Severe cartilage damage
• Femoral head chondral lesions
• Dysplasia without corrective surgery
• Advanced age with cartilage degeneration
• Significant degenerative changes

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Advanced Age

Patients older than:

• 40 years

particularly with cartilage damage, have an increased risk of failure after arthroscopy.

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Why These Patients Fail

These patients often already have:

• Irreversible joint degeneration

As a result:

• Arthroscopy cannot adequately restore hip mechanics

and progression to THA becomes likely.

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Causes of Failure of Hip Arthroscopy

Failure can be divided into:

• Patient-related factors
• Surgical factors

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Patient-Related Factors

Important patient-related risk factors include:

• Age greater than 40 years
• Osteoarthritis
• Severe cartilage damage
• Dysplasia
• Coxa profunda
• Protrusio acetabuli
• Obesity
• Genetic predisposition
• High-demand athletic activity

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Cartilage Damage

Severe cartilage injury is one of the strongest predictors of failure.

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Outerbridge Classification of Cartilage Damage

Grades III and IV are associated with:

• Poor prognosis after arthroscopy

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Surgical Factors Leading to Failure

1. Inadequate Cam Resection

The most common technical error is:

• Under-resection of the cam deformity

Residual impingement continues to damage:

• Labrum
• Cartilage

leading to persistent symptoms.

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2. Poor Labral Management

Historically, labral debridement was common.

Current evidence supports:

• Labral preservation
• Labral repair
• Labral reconstruction when necessary

Debridement alone is associated with:

• Inferior long-term outcomes

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3. Inadequate Capsular Management

Failure to preserve or repair the capsule may result in:

• Instability
• Persistent pain

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4. Missed Pathology

Failure to recognize associated conditions such as:

• Dysplasia
• Version abnormalities
• Chondral injury

may contribute to poor outcomes.

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Risk of Conversion to THA

Failure Rates

Reported failure rates after hip arthroscopy are approximately:

• 16% within 2 years

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Conversion Rates

Conversion to THA occurs in approximately:

• 7–20% of patients

depending on patient selection and degree of degeneration.

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Time to Conversion

The average time from arthroscopy to THA is approximately:

• 23–29 months

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Predictors of Conversion to THA

Several factors increase the likelihood of requiring THA after arthroscopy.

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Major Predictors

• Increasing age
• Poor preoperative hip scores
• Severe cartilage damage
• Joint space narrowing
• High alpha angle
• Femoral version abnormalities
• Osteoarthritis

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Joint Space Narrowing

Joint space less than:

• 2 mm

is one of the strongest predictors of poor outcome and early THA conversion.

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Outcomes of THA After Previous Hip Arthroscopy

Compared with primary THA, conversion THA after arthroscopy is generally associated with:

• Greater technical difficulty
• Higher complication rates
• Slightly inferior functional outcomes

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Comparison: THA After Arthroscopy vs Primary THA

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Why Conversion THA Is More Difficult

Prior arthroscopy may create:

• Scar tissue
• Capsular changes
• Altered anatomy

These factors increase surgical complexity during THA.

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Complications

Potential complications after THA following arthroscopy include:

• Infection
• Dislocation
• Persistent stiffness
• Technical challenges during exposure

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Clinical Pearls

1. Proper Patient Selection Is the Most Important Factor

A key principle is:

“The success of hip arthroscopy depends more on indication than technique.”

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2. Avoid Arthroscopy in Advanced Arthritis

Hip arthroscopy should generally be avoided when patients have:

• Advanced osteoarthritis
• Severe cartilage loss
• Joint space less than 2 mm

These patients often benefit more from:

• Early Total Hip Arthroplasty

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3. Technical Precision Is Essential

Successful arthroscopy requires:

• Adequate cam resection
• Labral preservation and repair
• Proper capsular management

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4. Type of FAI Influences Outcome

Patients with isolated:

• Cam deformities

generally have better outcomes than patients with:

• Pincer deformity
• Combined impingement

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Important Case-Based Insight

Patients with:

• Severe cartilage degeneration
• Soft femoral head cartilage
• Advanced chondral lesions

may progress rapidly toward:

• End-stage arthritis
• Early THA

despite arthroscopic intervention.

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Key Take-Home Messages

• Hip arthroscopy is an effective hip preservation procedure when performed in properly selected patients.
• Advanced arthritis and severe cartilage damage are major predictors of failure.
• Joint space less than 2 mm strongly predicts conversion to THA.
• Under-resection of cam lesions is the most common technical cause of failure.
• Labral repair is preferred over debridement.
• Conversion THA after arthroscopy is technically more challenging than primary THA.
• Appropriate patient selection is more important than surgical technique alone.

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Final Take-Home Message

The primary goal of hip arthroscopy is:

• Preservation of the native hip joint

However, not all patients are ideal candidates for hip preservation surgery.

Recognizing patients with:

• Advanced degeneration
• Significant cartilage loss
• Established osteoarthritis

is critical to avoid failed procedures and delayed definitive treatment.

In appropriately selected patients, early Total Hip Arthroplasty may provide:

• Better pain relief
• Faster recovery
• More predictable outcomes

than unsuccessful hip preservation attempts.