Quality comparison between two different types of platelet-rich plasma for knee osteoarthritis Takanori Wakayama, Yoshitomo Saita, Yohei Kobayashi, Hirofumi Nishio, Sayuri Uchino, Shin Fukusato, Hiroshi Ikeda and Kazuo Kaneko Regen Med Res, 8 (2020) 3 Published online: 03 December 2020 DOI: 10.1051/rmr/200002