Preferred Corticosteroid for Knee Injection
Triamcinolone hexacetonide is the preferred corticosteroid for knee injections, but since it's been unavailable in the US for years, use triamcinolone acetonide 20-40 mg as the practical alternative. 1, 2
First-Line Agent: Triamcinolone Hexacetonide
- Triamcinolone hexacetonide demonstrates superior durability and clinical response compared to triamcinolone acetonide in randomized trials and large observational studies. 1
- This agent provides better outcomes in maintaining remission compared to other injectable glucocorticoids. 1
- The FDA recently allowed importation of one specific formulation to address the shortage, so check availability at your institution. 1
Practical Alternative: Triamcinolone Acetonide
When triamcinolone hexacetonide is unavailable (which is most of the time):
- Use triamcinolone acetonide 40 mg for knee injections—this dose is as effective as 80 mg. 1, 2
- A lower dose of 20 mg triamcinolone is non-inferior to 40 mg for pain relief at 12 weeks in knee osteoarthritis. 3, 4
- Start with 40 mg for initial injections; consider 20 mg for repeat injections to minimize cumulative adverse effects on cartilage, bone density, and meniscal thickness. 1, 3
Other Acceptable Options
- Methylprednisolone 40 mg is an alternative that shows comparable efficacy to triamcinolone acetonide, with pain improvement at 4 and 24 weeks. 5, 6
- No significant differences exist between methylprednisolone acetate and triamcinolone acetonide in time to relapse (mean 20.8 vs 20.9 weeks). 6
Clinical Guidance
- Intra-articular corticosteroid injections are strongly recommended by the American College of Rheumatology for knee osteoarthritis with Level 1A+ evidence. 5, 1
- Particularly indicated for acute exacerbations with effusion. 5, 1
- Knee injections do not require ultrasound guidance (unlike hip injections which mandate imaging). 5
Critical Safety Considerations
- Avoid injections within 3 months before planned joint replacement surgery due to theoretical infection risk. 5, 1
- Expect time-limited benefit: pain relief lasts weeks to months, with triamcinolone showing improvement at 6 weeks but not consistently at 12 weeks. 5, 7
- Repeated injections carry risks of cartilage loss, reduced bone mineral density, and meniscal thinning—though cartilage changes haven't correlated with worsening pain or function in studies. 5, 1
- Instruct patients to avoid overuse of the injected joint for 24 hours, but don't immobilize completely. 1