2.5% polyacrylamide hydrogel - an observational proof-of-concept cohort study.

There is a drought of effective treatments of knee osteoarthritis (OA) and new therapies are needed. The present study has been conducted to establish an initial estimate of effectiveness of intra-articular (IA) injection of a proprietary 2.5% cross-linked polyacrylamide hydrogel (PAAG) for the treatment of knee OA symptoms and signs.