From the FDA Drug Label
A single local injection of triamcinolone acetonide is frequently sufficient, but several injections may be needed for adequate relief of symptoms. Initial dose: 2. 5 mg to 5 mg for smaller joints and from 5 mg to 15 mg for larger joints, depending on the specific disease entity being treated. For adults, doses up to 10 mg for smaller areas and up to 40 mg for larger areas have usually been sufficient.
The appropriate medication mixture with amounts for subtalar joint corticosteroid injections is 2.5 mg to 5 mg for smaller joints, and 5 mg to 15 mg for larger joints, depending on the specific disease entity being treated 1.
- The dosage may vary depending on the patient's response and the disease entity being treated.
- Strict aseptic technique is mandatory when administering the injection.
- The injection should be made into the joint space, and care should be taken to avoid injecting the suspension into the surrounding tissues.
From the Research
For subtalar joint corticosteroid injections, a recommended medication mixture includes 1-2 mL of a long-acting corticosteroid such as triamcinolone acetonide (20 mg/mL) or methylprednisolone acetate (20 mg/mL), combined with 1-2 mL of a local anesthetic like 1% lidocaine or 0.5% bupivacaine, as a dose of 20 mg triamcinolone is as effective as 40 mg for joint injections 2. The total injection volume should typically not exceed 3-4 mL to avoid excessive pressure in the joint space. The corticosteroid provides anti-inflammatory effects that can last for weeks to months, while the anesthetic offers immediate pain relief and confirms proper needle placement when patients report temporary numbness. Prior to injection, the skin should be properly prepared with antiseptic solution, and the procedure should be performed using sterile technique. The lateral approach is commonly used, with the needle inserted approximately 1 cm below the tip of the lateral malleolus and directed medially and slightly upward. These injections are typically limited to 3-4 per year in the same joint to minimize potential side effects such as cartilage damage, tendon weakening, and systemic corticosteroid absorption. Patients should be advised to rest the joint for 24-48 hours after injection to maximize therapeutic benefit. Key considerations for the procedure include:
- Using ultrasound guidance to increase the accuracy of injections and reduce procedural pain 2
- Selecting the appropriate corticosteroid dose, with 20 mg triamcinolone being as effective as 40 mg for joint injections 2
- Monitoring for potential adverse events, such as postinjection flare, skin reaction, and infection, although the risk of infection is low 3
- Limiting the number of injections per year to minimize potential side effects, with some studies suggesting a delay in surgical intervention with subtalar steroid injections 4