Abstract: The present invention relates to a composition comprising stem cells, a cell culture medium and a polyacrylamide hydrogel (PAAG), wherein the PAAG contains less than 0.02% Wmonomer/Wtotal PAAG] of a N-hydroxyethyl acrylamide (HEA) side chain. The invention also relates to the process of making the composition. In particular, the present invention relates to the composition, wherein the composition is administered by injection and wherein it is used in medicine, in particular for use in prevention and/or treatment of e.g. tendon injury in a mammal, arthritis in a mammal or arthropathy in a mammal. Tendon injury, arthritis or arthropathy may occur in a human, a racing animal or a companion animal.

Abstract: The present invention relates to a polyacrylamide hydrogel for use in prevention and/or treatment of synovitis or pain associated with synovitis in a mammal by formation of an extra layer to the synovial membrane i.e. a sub-synovial layer and a novel synovial lining layer. Synovitis may occur in association with arthritis, such as osteoarthritis or rheumatoid arthritis, lupus, or gout, and the mammal suffering from synovitis is a preferably a human, a racing animal or a companion animal.