Methods for determining the molecular composition of knee joint structures in osteoarthritis: collagen, proteoglycans and water content: a systematic review oleh Bogdan Raikov, Marina Lipina, Kirill Azarkin, Yuliya Goncharuk, Ivan Vyazankin, Eugene Kalinsky, Tagir Kudrachev, Emirkhan Murdalov, Eugene Nagornov, Gleb Budylin, Evgeny Shirshin, Nataliya Rovnyagina, Vadim Cherepanov, Anton Kurpyakov, Vladimir Telpukhov, Nikita Belov, David Pogosyan, Gennadiy Kavalerskiy, Andrey Gritsyuk, Andrey Garkavi, Alexey Lychagin