What is the treatment for Cam type Femoroacetabular Impingement (FAI)?

Treatment of Cam Type Femoroacetabular Impingement (FAI)

The treatment of cam type femoroacetabular impingement should begin with a conservative approach including physical therapy, activity modification, and pain management, progressing to arthroscopic surgical intervention if conservative measures fail, particularly in patients with femoral anteversion <16° and α-angle >65°. 1, 2

Diagnosis and Clinical Evaluation

Proper diagnosis of cam type FAI requires a combination of:

• Symptoms: Primarily groin pain, which may also radiate to the back, buttock, or thigh
• Clinical signs: Positive FADIR test (flexion, adduction, internal rotation)
• Imaging findings: Radiographic evidence of cam deformity (abnormal femoral head-neck junction)

Important: Diagnosis should never be made using imaging alone 1

Initial Imaging

• AP pelvis and lateral femoral head-neck radiographs to assess for structural abnormalities
• MRI hip without IV contrast or MR arthrography to evaluate labral tears and cartilage damage 3, 1

Treatment Algorithm

1. Conservative Management (First-Line)

Conservative treatment has shown moderate to large effect sizes for both pain and function, with success rates of 53-78% for return to play in athletes 1, 4.

Components of conservative management:

• Patient education:

  • Explanation of FAI pathology
  • Activity modification strategies
  • Pacing techniques

• Exercise therapy:

  • Core strengthening
  • Hip girdle muscle strengthening
  • Range of motion exercises
  • Aerobic activity
  • Progressive exercise advancement every 1-2 weeks based on tolerance

• Pain management:

  • Paracetamol (up to 4g/day) as first-line analgesic
  • NSAIDs at lowest effective dose if inadequate response to paracetamol

• Lifestyle modifications:

  • Weight management
  • Appropriate footwear
  • Consideration of walking aids if needed

Caution: Physical therapy may be less effective in patients with femoral anteversion <16° and α-angle >65°, who may require earlier surgical intervention 2

2. Surgical Management

Surgical intervention is indicated when:

• Conservative treatment fails after 3-6 months
• Significant pain and functional limitations persist
• Imaging confirms cam deformity with or without associated labral/cartilage damage

Hip arthroscopy is the preferred surgical approach for patients meeting these criteria:

• Age <50 years
• Minimal or no osteoarthritis
• No inflammatory arthritis 1

Surgical procedures include:

1. Femoral osteoplasty (cam resection):

   • Removal of the abnormal bone at the femoral head-neck junction
   • Restoration of normal femoral morphology
   • Normalization of joint contact stresses 5

2. Management of associated pathology:

   • Labral repair: Superior to debridement for long-term outcomes
   • Cartilage treatment: Based on the extent of damage:
     • Debridement for minor damage
     • Microfracture for full-thickness chondral lesions <3 cm² 3
     • Matrix-assisted chondrocyte implantation (MACI) for larger lesions >2 cm² 3

Outcomes and Prognosis

• Accurate arthroscopic cam resection can restore normal mechanical environment of the hip joint 5
• Without proper treatment, FAI can lead to progressive joint damage and early osteoarthritis 1, 6
• Arthroscopic labral repair combined with cam resection shows better outcomes than debridement alone 1

Follow-up and Monitoring

Regular follow-up (at least annually) is necessary to monitor:

• Progression of symptoms
• Development of early osteoarthritis
• Functional status 1

Important Considerations

• Early intervention is crucial to prevent progression to osteoarthritis
• Complete cam resection is important for normalizing joint mechanics 5
• Patients with prominent cam deformity (α-angle >65°) and lower femoral anteversion (<16°) may have poorer outcomes with conservative treatment alone 2