Factors predicting long-term efficacy of Hylan GF-20 viscosupplementation in knee osteoarthritis.

Objectives: To describe the long-term effects of Hylan GF-20 viscosupplementation in patients with knee osteoarthritis and to identify factors predicting efficacy.

Methods: One hundred and fifty-five patients (80 women and 75 men; mean age, 69 years) with symptomatic knee osteoarthritis each received three intraarticular Hylan GF-20 injections. Effectiveness, safety, and satisfaction were evaluated 7-14 months later based on a physician's examination and a five-item questionnaire.