Abstract Introduction/purpose The purpose of this systematic review was to evaluate the effect of iron supplementation during total knee arthroplasty (TKA): (1) Is the iron supplementation necessary during TKA. (2) When is the optimal timing of iron supplementation. (3) Which is better. between orally and intravenously administered iron supplementation. https://www.parisnaturalfoodes.shop/product-category/phosphatidyl-choline/