Viscosupplementation with hylan for the treatment of osteoarthritis: findings from clinical practice in Canada.

OBJECTIVE: To evaluate viscosupplementation with intraarticular hylan G-F 20 in current clinical practice. METHODS: A retrospective study of all patients with osteoarthritis of the knee treated with hylan by 5 Canadian clinicians over a period of 2.5 years. RESULTS: A total of 1537 injections were performed in 336 patients involving 458 knees. The overall response and the change of activity level were judged better or much better for 77 and 76% of the treated knees after the first course of treatment (3 weekly injections), and 87 and 84% after a 2nd course. The mean time elapsing between the first and 2nd course, 8.2 +/- 0.5 months, is an evaluation of the duration of benefits. Local adverse events were observed in 28 patients (32 knees), with an overall rate of 2.7% adverse events per injection, 7.0% per joint, and 8.3% per patient. No systemic adverse events were noted in any patient. The adverse events were characterized by pain and/or transient swelling of the injected joint, mostly mild or moderate in intensity, and 72% of the adverse events were considered to be possibly or probably related to the injection. The incidence of adverse events is significantly influenced by the injection technique: 5.2% adverse events per injection with a medial approach to a partially bent knee, and 2.4% (straight medial) and 1.5% (straight lateral). After an adverse event, clinical improvement still occurred in 69% of the affected knees. CONCLUSION: Hylan G-F 20 provided good clinical benefits and an acceptable safety profile in current clinical practice. The occurrence of adverse events after an intraarticular hylan injection is infrequent and unpredictable and is not necessarily hylan related, although injection related.