Courtesy: NewYorkOrtho

Hip Arthroscopy: Current Concepts, Advanced Applications, and Emerging Techniques

Introduction

Hip arthroscopy has undergone remarkable evolution over the past several decades. What was once considered a niche procedure is now a cornerstone of modern hip preservation surgery.

In the 1980s, many patients with hip pain were broadly diagnosed with bursitis, tendonitis, or arthritis. During the 1990s and early 2000s, recognition of labral pathology transformed the understanding of hip disorders. The subsequent development of arthroscopic labral repair techniques further expanded treatment options.

Today, hip arthroscopy focuses not only on treating intra-articular pathology but also on correcting underlying structural abnormalities and managing selected extra-articular disorders.

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Femoroacetabular Impingement (FAI)

Definition

Femoroacetabular impingement is a mechanical conflict between the femoral head-neck junction and the acetabular rim.

Repeated abnormal contact results in:

• Labral injury
• Chondral damage
• Progressive joint degeneration
• Early osteoarthritis

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Types of Femoroacetabular Impingement

Cam Impingement

Cam-type impingement is most commonly seen in young, active males.

Pathology

• Loss of normal femoral head-neck offset
• Increased radius of the femoral head-neck junction
• Abnormal contact during hip flexion and rotation

Consequences

• Chondrolabral junction injury
• Cartilage delamination
• Labral tears
• Progressive cartilage loss

Arthroscopic Treatment

• Femoral osteoplasty
• Restoration of normal head-neck offset

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Pincer Impingement

Pincer-type impingement is more commonly observed in middle-aged females.

Pathology

• Acetabular overcoverage of the femoral head
• Acetabular retroversion in some cases

Consequences

• Linear compression of the labrum
• Labral degeneration
• Progressive joint damage

Arthroscopic Treatment

• Acetabular rim trimming
• Labral preservation and repair whenever possible

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Mixed-Type Impingement

Mixed impingement combines features of both cam and pincer deformities.

This is the most common form of femoroacetabular impingement encountered in clinical practice.

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Arthroscopic Findings in FAI

Common findings during hip arthroscopy include:

• Chondrolabral junction injury
• Cartilage delamination
• Labral tears
• Exposed subchondral bone

One characteristic finding is the “carpet lesion,” where cartilage separates from underlying bone, exposing subchondral bone and representing an early stage of osteoarthritis.

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Complications Unique to Hip Arthroscopy

Traction-Related Complications

Because hip arthroscopy requires joint distraction, traction-related complications are unique to this procedure.

Pudendal Nerve Injury

Potential manifestations include:

• Perineal numbness
• Sensory disturbances
• Temporary sexual dysfunction

Prevention

Modern techniques increasingly utilize:

• Post-less traction systems
• Trendelenburg positioning
• Specialized foam support devices

These approaches reduce pressure on the perineum and lower the risk of nerve injury.

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Advanced Applications of Hip Arthroscopy

Cartilage Lesions

Cartilage defects are commonly encountered in the anterosuperior acetabulum.

Available Techniques

• Microfracture
• Autologous chondrocyte implantation (ACI)
• Matrix-Induced Autologous Chondrogenesis (AMIC)

These procedures aim to restore joint surface integrity and delay osteoarthritis progression.

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Synovial Disorders

Pigmented Villonodular Synovitis (PVNS)

Now more accurately termed tenosynovial giant cell tumor.

Arthroscopic Management

• Synovectomy
• Complete lesion excision

Complete resection is critical to minimize recurrence risk.

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Greater Trochanteric Pain Syndrome (GTPS)

GTPS includes:

• Trochanteric bursitis
• Gluteus medius tears
• Gluteus minimus tears

Treatment Options

Endoscopic Repair

Suitable for:

• Partial tears
• Selected full-thickness tears

Open Repair

Preferred for:

• Large tears
• Retracted tears
• Severe tendon degeneration

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Snapping Hip Syndrome

Internal Snapping Hip

Usually caused by iliopsoas tendon movement.

Treatment Options

• Arthroscopic iliopsoas release within the central compartment
• Release at the level of the lesser trochanter

Although mild weakness may occur, it is usually not clinically significant.

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External Snapping Hip

Caused by the iliotibial band snapping over the greater trochanter.

Treatment

• Endoscopic or open IT band release

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Iliopsoas Impingement After Total Hip Arthroplasty

Prominent acetabular components can irritate the iliopsoas tendon following hip replacement.

Preferred Treatment

• Endoscopic iliopsoas tendon release

This approach often avoids the need for revision arthroplasty.

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Revision Hip Arthroscopy

Common Causes of Failure

The most frequent reasons for failed primary hip arthroscopy include:

1. Residual cam deformity
2. Residual pincer deformity
3. Persistent labral pathology
4. Cartilage injury
5. Capsular insufficiency
6. Postoperative adhesions

Most Common Cause

Inadequate bony resection remains the leading cause of revision surgery.

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Outcomes of Revision Surgery

Although revision arthroscopy can improve symptoms, outcomes are generally inferior to those achieved with primary procedures.

Careful preoperative evaluation and correction of residual pathology are essential.

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Capsular Management

Importance of the Hip Capsule

The capsule plays a crucial role in:

• Joint stability
• Rotational control
• Prevention of micro-instability

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Current Trend

Earlier techniques often left the capsule unrepaired.

Current evidence increasingly supports:

• Routine capsular closure
• Capsular preservation whenever possible

These measures help reduce postoperative instability and improve functional outcomes.

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Labral Reconstruction

Indications

Labral reconstruction may be considered when:

• The native labrum is irreparable
• Significant degeneration is present
• Revision surgery is being performed

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Techniques

Segmental Reconstruction

Used when a localized segment of the labrum is deficient.

Circumferential Reconstruction

Used for extensive labral deficiency.

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Graft Options

• Autografts
• Allografts

Outcomes

Current evidence suggests that reconstruction:

• Produces superior outcomes compared with debridement
• May approach or exceed repair outcomes in selected revision cases

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Extra-Articular Disorders Treated Arthroscopically

Hip arthroscopy has expanded beyond the central and peripheral compartments.

Greater Trochanter Region

Treatable conditions include:

• Gluteus medius tears
• Calcific tendinitis
• External snapping hip

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Lesser Trochanter Region

Ischiofemoral Impingement

Can be addressed arthroscopically in selected patients.

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Ischial Tuberosity

Procedures include:

• Chronic proximal hamstring repair
• Sciatic nerve decompression

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Deep Gluteal Space

Deep Gluteal Syndrome

Previously known as piriformis syndrome.

Arthroscopy allows:

• Sciatic nerve decompression
• Treatment of fibrous bands and entrapment lesions

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Important Surgical Considerations

Hip arthroscopy remains technically demanding because the hip is:

• Deeply located
• Highly constrained
• Surrounded by critical neurovascular structures

Successful surgery requires:

• Adequate traction
• Fluoroscopic guidance
• Precise portal placement
• Advanced arthroscopic skills

The learning curve is substantial and requires dedicated training.

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Hip Arthroscopy in Avascular Necrosis (AVN)

Staging of AVN

Stage I

• Normal radiographs
• MRI demonstrates osteonecrosis

Stage II

• Sclerosis and cyst formation
• No femoral head collapse

Stage III

• Femoral head collapse
• Crescent sign present

Stage IV

• Secondary arthritis
• Acetabular involvement

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Kerboul Angle

The Kerboul angle helps predict prognosis by measuring lesion size.

Grade	Angle	Prognosis
I	<200°	Good
II	200–249°	Moderate
III	250–299°	Poor
IV	>300°	Very Poor

A Kerboul angle greater than 250° is associated with a high risk of failure following core decompression.

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Core Decompression

Indications

• Pre-collapse AVN
• Ficat Stage I and II disease

Success Rate

Approximately 60–80% at short- to mid-term follow-up.

Poor Prognostic Factors

• Large lesions
• Femoral head collapse
• Ongoing steroid use
• High Kerboul angle

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Arthroscopy-Assisted Core Decompression

An emerging technique offering several advantages:

• Accurate lesion localization
• Simultaneous treatment of labral pathology
• Assessment of cartilage status
• Potential reduction in radiation exposure

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Hip Arthroscopy in Dysplasia

Pathophysiology

A shallow acetabulum creates increased shear forces across the hip joint.

Consequences include:

• Labral overload
• Labral tears
• Micro-instability
• Progressive degeneration

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Lateral Center Edge Angle (LCEA)

Classification	Angle
Normal	>25°
Borderline Dysplasia	20–25°
Dysplasia	<20°

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Indications for Arthroscopy

Hip arthroscopy should generally be reserved for patients with:

• Borderline dysplasia (LCEA 20–25°)
• Clearly defined intra-articular pathology

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Historical Outcomes

Arthroscopy alone in true dysplasia has demonstrated:

• High failure rates
• Persistent instability
• Progression to osteoarthritis
• Increased conversion to total hip arthroplasty

For patients with significant dysplasia, corrective procedures such as periacetabular osteotomy remain the preferred treatment.

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Key Takeaways

• Hip arthroscopy has evolved from a niche procedure to a comprehensive hip preservation tool.
• Femoroacetabular impingement remains the most common indication for surgery.
• Adequate correction of cam and pincer deformities is critical to long-term success.
• Capsular preservation and closure have become important principles in modern hip arthroscopy.
• Arthroscopic techniques continue to expand into the management of cartilage lesions, tendon disorders, nerve entrapment syndromes, and selected cases of avascular necrosis.
• Revision surgery is most commonly required because of residual bony deformity.
• Dysplasia must be carefully assessed, as arthroscopy alone is often inadequate in patients with significant structural instability.
• Successful outcomes depend on appropriate patient selection, precise surgical technique, and a thorough understanding of hip biomechanics.