The Efficacy of Platelets Rich Plasma Injection With PRGF Method in the Treatment for Osteoarthritis of the Subtalar Joint

The investigators will try to find any efficacy of platelet rich plasma injection for the treatment of osteoarthritis (OA) in the subtalar joint. Autologous platelet-secreted growth factors (GFs) may have therapeutic effects in OA capsular joints via multiple mechanisms. The investigators aim is to examine the effect of a platelet-derived preparation rich in growth factors(PRGFs) in OA of the subtalar joint, using parameters of pain, function, quality of life and safety.