The use of tourniquets in total knee replacement (TKR) remains controversial. Purported benefits include less blood loss, better surgical field visualization, and quicker operative times. On the other hand, there are concerns with regards to vascular damage, and post-operative pain and muscle function. In this study, the authors randomized 200 patients undergoing primary TKR to undergo surgery with or without tourniquet. Outcomes included pain, functional outcomes, satisfaction, and range of motion. Patients who underwent surgery with a tourniquet had significantly less blood loss, but there was no difference in the majority of other functional, satisfaction, or pain outcomes.