Management of Cam-Type FAI with Moderate Hip Osteoarthritis
For patients with cam-type femoroacetabular impingement and moderate (Tönnis grade 2) hip osteoarthritis, proceed with conservative management first using NSAIDs, physical therapy, and intra-articular corticosteroid injections, but understand that hip arthroscopy has limited durability with 41% requiring total hip arthroplasty within 10 years 1, 2.
Initial Conservative Management
Start with a structured non-operative approach:
- NSAIDs should be used when not contraindicated (high-quality evidence, strong recommendation) 1
- Physical therapy could be considered for mild-to-moderate symptomatic hip OA (high-quality evidence, moderate recommendation) 1
- Intra-articular corticosteroid injections could be considered (high-quality evidence, moderate recommendation) 1
- Avoid hyaluronic acid injections - these should NOT be used for symptomatic hip OA (high-quality evidence, strong recommendation) 1
Acetaminophen may be considered as an adjunct when not contraindicated (consensus evidence) 1.
Critical Decision Point: Surgery vs. Continued Conservative Care
The presence of moderate osteoarthritis (Tönnis grade 2) fundamentally changes the risk-benefit calculation for hip arthroscopy. Patients with Tönnis grade 2 at baseline have a 3.44 times higher risk of conversion to total hip arthroplasty compared to Tönnis grade 1 2.
When Hip Arthroscopy May Still Be Considered
Despite the high conversion rate, hip arthroscopy can provide meaningful functional improvement for select patients:
- 67% of patients who avoid THA exceed the minimal important change threshold in patient-reported outcomes 2
- 79% of non-THA patients report satisfaction with surgery at 10 years 2
- Mean iHOT-12 scores improve from 41.4 preoperatively to 71.0 at long-term follow-up (p < 0.001) 2
Key Contraindications to Hip Arthroscopy
Do NOT proceed with hip arthroscopy if:
- Age ≥55 years (independent risk factor for THA conversion) 3
- Tönnis grade 3 osteoarthritis 4
- Joint space <2 mm 4
- Bipolar cartilage defects 4
- Higher body mass index 4
Surgical Technique Considerations
If proceeding with surgery in this challenging population, the approach matters:
- Combined hip arthroscopy with limited open osteochondroplasty allows direct visualization and improved quality of cam resection 5, 3
- Microfracture should be performed for well-circumscribed full-thickness chondral lesions <3 cm² with intact subchondral bone and healthy surrounding cartilage 6
- Target alpha angle reduction to <45° on cross-table lateral radiographs 5
Setting Realistic Expectations
This is the most critical aspect of management. Patients must understand:
- Nearly two-fifths of hips will require THA within 10 years despite arthroscopic intervention 2
- Mean time to THA is 7.1 years after hip arthroscopy 2
- The surgery may provide symptomatic relief but does not halt osteoarthritis progression in most cases
- Clinical equipoise exists - outcomes show benefit but improvement may not be as favorable as desired 4
When to Proceed Directly to Total Hip Arthroplasty
Consider THA as the primary intervention when:
- Conservative measures have failed AND patient meets high-risk criteria above
- Patient has realistic expectations about recovery and social support for postoperative care 1
- Symptoms are refractory and significantly impair quality of life
Common Pitfalls to Avoid
- Do not perform hip arthroscopy based solely on imaging findings - cam morphology is common in asymptomatic hips and does not automatically warrant surgery 7, 8
- Do not delay indicated surgery with insurance denials - when intervention is appropriate, timely treatment both addresses symptoms and may mitigate further cartilage damage 9
- Do not underestimate the wide variation in chondral damage - radiographs may appear similar in Tönnis grade 2, but arthroscopic findings vary considerably 4
- Avoid prophylactic surgery on asymptomatic contralateral hips - despite theoretical concerns, this cannot be recommended currently 9