OBJECTIVES: To observe, under actual conditions of use, the pain  effect obtained, in the context of management of knee osteoarthritis, combining a prescription of Avian ACS  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; the investigator does not change the prescription or management habits. RESULTS: A total of 201 patients are treated with hyaluronic acid and Avian ACS . The average age is 65.30 years (±7.10). Average pain during activities of daily living (ADL) was measured by means of a visual analogue scale (VAS) . It is 52.02 ±20.53 at inclusion.  At 6 months, this same average pain measured under the same conditions is 33.58±25.21. A third measurement at 12 months situates it at 30.44±22.86. Pain during ADL is significantly reduced between inclusion and month 6 (p<0.0001) and between inclusion and month 12 (p<0.0001). Accordingly, the reduction obtained in 12 months is 41%. With regard to pain measured at rest, it was also measured at inclusion, at 6 and 12 months, by means of VAS. There is a significant reduction in pain at rest between inclusion and 6 months (p=0.0052) and the reduction between inclusion and month 12 is also significant (p=0.0005). At inclusion, 6 and 12 months, the average pain observed is 29.86±21.16, 20.95±23.13 and 17.33±6.97, respectively. CONCLUSIONS: Our study, which assesses the effect on pain obtained in the context of management of subjects with knee osteoarthritis, combining a prescription of Avian ACS between 2 courses of treatment of 3 injections of hyaluronic acid, showed a reduction in pain during ADL. This reduction in pain, which is significant at 6 months, then perpetuated at 12 months, shows the relevance of the treatment protocol used by the doctors.