OBJECTIVES: To observe, under actual conditions of use,  the effect obtained, in the context of management of knee osteoarthritis, combining a prescription of Avian ACS (1 g/day) between 2 courses of treatment of 3 injections of hyaluronic acid spaced out by a maximum of 12 months. METHODS: Pragmatic, longitudinal and prospective follow-up carried out by rheumatologists in the context of their daily professional activities RESULTS: The results presented come from a preliminary analysis concerning the first patients assessable at 6 months.  Forty-five percent of the patients are treated with hyaluronic acid for left knee osteoarthritis and 52% are treated with hyaluronic acid for right knee osteoarthritis (3% treated for both). Average pain during activities of daily living was measured by means of a visual analogue scale. It is 53.28 ±20.83 at inclusion. At 18 weeks, this same average pain measured under the same conditions is 37.96 ±17.17. A third measurement at 24 weeks situates it at 35.62 ±17.95. Pain during activities of daily living is significantly reduced between inclusion and week 18 (p=0.0056). The average reduction in pain during activities of daily living measured between inclusion and 6 months is also significant (p=0.001). Accordingly, the reduction obtained in 6 months is 33%. CONCLUSIONS: Our study, which assesses the effect on pain obtained in the context of management of subjects with knee osteoarthritis, combining a prescription of Structum® (1 g/day) between two courses of treatment of three injections of Structovial® , showed a reduction in pain during activities of daily living.  This reduction in pain, which is significant at 18 weeks, then perpetuated at 6 months, shows the relevance of the treatment protocol used by the doctors.