What is the best treatment approach for a young to middle-aged adult with a history of athletic activity or hip trauma diagnosed with cam deformity of the hip?

Cam Deformity of the Hip: Treatment Approach

For young to middle-aged active adults with cam deformity, treatment should be based on symptoms, not imaging alone—asymptomatic cam morphology requires no intervention beyond activity modification and monitoring, while symptomatic patients with positive clinical examination findings should undergo 3-6 months of conservative management before considering arthroscopic cam resection. 1

Critical Distinction: Morphology vs. Syndrome

The presence of cam morphology (alpha angle >60°) on imaging does not automatically warrant treatment, as this finding is extremely common in asymptomatic individuals 1. The diagnosis of femoroacetabular impingement (FAI) syndrome requires all three components:

• Hip-related groin pain (though pain may also present in back, buttock, or thigh) 2
• Positive clinical examination findings, particularly a positive flexion-adduction-internal rotation (FADIR) test 2, 1
• Imaging confirmation of cam morphology 2

A critical pitfall: Never operate on imaging findings alone—cam morphology without clinical symptoms does not warrant surgery. 1, 3

Management Algorithm for Asymptomatic Cam Morphology

For patients with cam deformity but no symptoms:

• No treatment is required 1
• Educate patients about activity modification to avoid repetitive deep hip flexion combined with internal rotation movements that increase impingement risk 1
• Monitor annually with clinical assessment for development of symptoms 1
• Counsel that cam deformities confer a 4.3-fold increased risk of developing hip pain over 4-5 years, particularly with alpha angles >60° at the 1:30 clock position and internal rotation <20° 4

Important caveat: Research demonstrates that adolescent athletes with cam deformities and limited hip internal rotation (<10°) show progressive degenerative MRI changes over 5 years, with 27% progressing from Tönnis grade 0 to grade 1 5. However, the majority remain asymptomatic, and prophylactic surgery is not indicated 1.

Conservative Management for Symptomatic Patients

When patients meet diagnostic criteria for FAI syndrome (symptoms + positive exam + imaging), initiate a 3-6 month trial of conservative treatment 1, 3:

• Activity modification avoiding provocative positions (deep flexion with internal rotation) 1
• Physical therapy focused on hip strengthening and range of motion
• NSAIDs for symptomatic relief during acute pain episodes 1

Surgical Indications

Proceed to arthroscopic cam resection (femoral osteoplasty) when: 1

1. Conservative management fails after 3-6 months of appropriate physical therapy 1, 3
2. Persistent hip-related pain with positive FADIR test continues 1
3. MRI or MR arthrography demonstrates associated labral tears or chondral damage requiring concurrent treatment 1, 3

Pre-operative imaging considerations: When surgery is being considered, obtain MRI or MR arthrography to identify labral tears, chondral defects, or ligamentum teres pathology that may require concurrent surgical treatment 2, 1. Delaying this advanced imaging represents a critical pitfall that can lead to incomplete surgical planning 1.

Surgical Technique and Concurrent Pathology Management

The evidence supports specific approaches for associated cartilage damage found during cam resection:

For grade 2-3 chondral lesions <3 cm²: Microfracture during arthroscopic cam resection produces substantially higher functional scores than chondroplasty alone 1. This achieves 93% defect fill with good-quality fibrocartilage at second-look arthroscopy 1.

For larger defects >2 cm² with Tönnis grade 2 osteoarthritis: Matrix-assisted autologous chondrocyte implantation (MACI) produces superior outcomes compared to simple debridement 1.

Evidence Supporting Surgical Correction

Research demonstrates that surgical correction of cam deformity in symptomatic FAI patients not only improves clinical function but also shows biomechanical benefits: decreased T1ρ MRI values (reflecting stabilization of cartilage degeneration) and 5% decrease in bone mineral density in the anterosuperior acetabular impingement zone at 2-year follow-up 6. These findings represent the first evidence that altering hip biomechanics through surgical intervention improves overall joint health 6.

Natural History and Risk Stratification

Understanding prognosis helps guide treatment decisions:

• Cam deformities are acquired during skeletal growth and may be influenced by high-impact sporting activities 7
• Major cam abnormalities confer high risk for hip osteoarthritis development 7
• Patients with cam deformity have 4.3-fold increased risk of developing hip pain (95% CI: 2.3-7.8) 4
• Limited internal rotation ≤20° increases risk 3.1-fold (95% CI: 1.6-6.0) for developing hip pain 4

Differential Diagnosis Considerations

Before diagnosing FAI syndrome, exclude serious pathology including Perthes' disease, slipped capital femoral epiphysis (SCFE), infection, osteoarthritis, tumors, and fractures 2. This is particularly critical in adolescent patients where SCFE must be ruled out first 8.