What is the treatment for mild cam (cam-type femoroacetabular impingement) morphology?

Treatment of Mild Cam Morphology

For asymptomatic or mildly symptomatic patients with cam morphology, observation with activity modification and physical therapy is the appropriate initial approach, reserving surgical correction only for those who develop symptomatic femoroacetabular impingement (FAI) syndrome that fails conservative management. 1

Understanding Cam Morphology vs. FAI Syndrome

• Cam morphology (alpha angle >60°) is an anatomical finding that does not automatically require treatment, as incidental findings are common in asymptomatic individuals 1
• Diagnosis should never be made on imaging alone—cam morphology only becomes clinically significant when combined with hip-related pain and positive clinical examination findings (such as positive FADIR test) 1
• The presence of cam morphology without symptoms represents a risk factor for future cartilage damage but does not mandate immediate intervention 2, 3

Initial Conservative Management Algorithm

For Asymptomatic Cam Morphology

• No treatment is required—these patients should be educated about activity modification to avoid repetitive deep hip flexion and internal rotation movements that increase impingement risk 1
• Monitor for development of symptoms with annual clinical assessment 1

For Mild Symptoms with Cam Morphology

• Initiate structured physical therapy focusing on posterior pelvic tilt exercises, hip muscle strengthening, and neuromuscular control 4
• Physical therapy may improve hip range of motion by optimizing pelvic positioning and muscle balance 4
• However, physical therapy has significant limitations: it is likely to fail when femoral anteversion is <16° and alpha angle is >65°, as these patients cannot achieve sufficient ROM improvement through conservative measures alone 4
• Activity modification to avoid provocative positions (deep flexion with internal rotation) 1
• NSAIDs for symptomatic relief during acute pain episodes 5

Surgical Indications and Timing

Surgical correction (arthroscopic cam resection/femoral osteoplasty) should be considered when:

• Conservative management fails after 3-6 months of appropriate physical therapy 1, 5
• Persistent hip-related pain with positive clinical examination findings (positive FADIR test) 1
• MRI or MR arthrography demonstrates associated labral tears or chondral damage requiring concurrent treatment 1
• Alpha angle >65° with femoral anteversion <16°, as these patients are at high risk of conservative treatment failure 4

Surgical Benefits

• Arthroscopic femoral osteoplasty improves clinical function scores and squat performance 2
• Surgery alters hip biomechanics to improve overall joint health: studies demonstrate decreased T1ρ MRI values (indicating stabilization of cartilage degeneration) and decreased subchondral bone mineral density in the impingement zone at 2-year follow-up 2
• Strong correlation exists between improved clinical functional scores and improved cartilage health markers (r = -0.86) 2

Surgical Approach for Associated Chondral Injuries

• For grade 2-3 chondral lesions <3 cm²: microfracture during arthroscopic cam resection produces substantially higher functional scores than chondroplasty alone 1
• For grade 4 chondral defects: microfracture 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 (Harris Hip Score 87.4 vs. 56.3 at 74-month follow-up) 1

Critical Pitfalls to Avoid

• Do not operate on imaging findings alone—cam morphology without clinical symptoms does not warrant surgery 1
• Do not assume all patients will respond to physical therapy—those with prominent deformities (alpha angle >65°) and low femoral anteversion (<16°) are likely to fail conservative treatment and should be counseled accordingly 4
• Do not delay advanced imaging when surgery is being considered—MRI or MR arthrography is necessary to identify labral tears, chondral defects, or ligamentum teres pathology that may require concurrent surgical treatment 1, 5
• Recognize that cam morphology causes altered joint mechanics even during low-demand activities: patients demonstrate 1.38-2.54 mm changes in bone-to-bone distance during walking compared to 1.16-1.84 mm in controls, which may contribute to progressive cartilage damage 3
• Understand that cam deformities have 47-78% higher subchondral bone mineral density than normal bone, which increases subchondral stiffness and contact stresses, potentially accelerating degeneration even in asymptomatic patients 6