The Effect of Hair Removal on Intraoperative Contamination

A prospective, non-blinded, randomized controlled trial with the purpose of investigating, whether preoperative electrical clipping of body hair affects the risk of intraoperative contamination. The primary investigators hypothesis is this: Preoperative electrical clipping of body hair in the operative field lowers the risk of intraoperative contamination. 200 male participants, 18 years or older, with a planned primary knee replacement surgery, will be enrolled. During surgery, four microbiological samples will be taken from each participant. The primary outcome is whether there is intraoperative contamination of the surgical site or not, determined by identification of any grown bacteria from the samples. If this study finds, that the contamination rate is lowered by preoperative electrical clipping of body hair, it will provide a cost-effective method of reducing the risk of intraoperative contamination and consequent postoperative infection, a solid argument for a change of current guidelines for preoperative hair removal, and provide additional information pointing towards body hair as a possible explanation for the increased infection rate in men.