hydrocortisone + yttrium-90 silicate

This combination consists of hydrocortisone, a corticosteroid with anti-inflammatory properties, and yttrium-90 silicate, a radiopharmaceutical that delivers targeted beta radiation to diseased synovial tissue. The yttrium-90 silicate component has been used for radiosynovectomy of large joints, particularly the knee, though it has been reported that yttrium-90 silicate has been withdrawn from the market in some regions, with yttrium-90 citrate becoming the primary agent for this purpose[2]. Yttrium-90 is a high-energy beta emitter with a half-life of 64 hours (2.7 days)[5][6]. When injected into a joint, it delivers localized radiation to the synovial membrane, helping to reduce inflammation and pain. The addition of hydrocortisone likely provides immediate anti-inflammatory effects while the radiopharmaceutical component works over a longer period. Clinical studies have shown that yttrium-90 silicate radiosynovectomy can be effective in reducing pain and improving joint function in patients with osteoarthritis. In one study, the overall success rate (defined as ≥50% improvement in visual analog scale pain scores) was 83.8% after six months, with remission of night pain achieved in 88.6% of cases and improved knee flexibility in 65.1% of patients[3]. The treatment appears to be most effective in patients with less advanced radiographic changes, younger age, and shorter disease duration[3]. Side effects of the treatment were reported to be minor and not significant over the follow-up period.