The objective of this study is to evaluate the effects of intraoperative application of iodine impregnated self-adhesive drapes on the bacterial quantity (colony forming units) of the skin in patients scheduled for total knee replacement surgery (TKA). We wish to investigate if intraoperative draping with an IIAD increases re-colonization with skin microbes compared to no drape use during simulated TKA surgery. Primary outcome is microbial quantity, while secondary outcome is identification of viable organisms on the skin. The hypothesis is that IIAD increases re-colonization of skin microbes compared to no drape use.