A Comparison of Outcomes With and Without a Tourniquet in Total Knee Arthroplasty A Systematic Review and Meta-analysis of Randomized Controlled Trials Ilhan Alcelik, MRCS,* Raymond D. Pollock, PhD, MPH,* Mohammed Sukeik, MRCS, y Josette Bettany-Saltikov, PhD, MSc, MCSP, z Patrick M. Armstrong, FRCS,* and Peter Fismer, MD* Abstract: A tourniquet is often used in total knee arthroplasty resulting in improved visualization of structures, reduced intraoperative bleeding and better cementation. The risks include deep vein thrombosis and pulmonary embolism. To quantify the case for or against tourniquet use, we carried out a systematic review and meta-analysis of selected randomized controlled trials. Ten studies were included in the meta-analysis. Of the 8 outcomes analyzed (surgery duration; total, intraoperative, and postoperative blood losses; deep vein thrombosis; pulmonary embolism; and minor/major complications), the total and intraoperative blood losses were less using a tourniquet. Minor complications were more common in the tourniquet group. The remaining outcomes showed no difference between the groups. Using a tourniquet may be beneficial, but long-term studies of outcome are needed. Keywords: tourniquet, total knee arthroplasty, meta-analysis. © 2011 Elsevier Inc. All rights reserved. Tourniquets are widely used during surgery, but there are complications associated with their use, namely, skin burns, soft tissue and muscle damage, injury of calcified vessels, increased swelling and stiffness of the joints, nerve injury, paralysis, and, rarely, acute pulmonary edema and cardiac arrest after release of a tourniquet [1-8]. Total knee arthroplasty (TKA) is a common procedure that is increasing due to an aging population. In 2010, about 60 000 TKAs were performed in England and whales in the NHS [9]. A tourniquet is often used in TKA to achieve better visualization of the structures and to reduce intraoperative blood loss. Arguably, the main advantage for using a tourniquet is achieving superior cementation due to a relatively blood-free operating field [10]. For some knee surgeons, these benefits outweigh the risks, and they operate without a tourniquet. Systematic review and meta-analysis are an accepted research methodology that quantitatively integrate the results of a collection of studies on a given topic. There has been no published systematic review or meta- analysis on tourniquet use in TKA, apart from a recent analysis [11] that, in our opinion, has methodological weaknesses. This is because of inclusion of studies with incomparable groups and nonrandomized and observa- tional studies. Such studies should not be included in an interventional review because they are likely to have biases that cannot be corrected by meta-analysis. In addition, the authors excluded 8 of their originally included studies in the meta-analysis because of hetero- geneity and only made a narrative analysis of that group. Therefore, using a more robust analysis, our aim was to determine whether a tourniquet should be used during TKA in adults so that surgeons can make an evidence- based decision on their use. We have used properly randomized studies only (level I evidence). Our hypoth- esis is that use of a tourniquet would reduce the duration of surgery reduce intraoperative, postoperative, and total blood losses and improve knee flexion. We also analyzed From the *Department of Orthopaedics, West Cumberland Hospital, Whitehaven, UK; yDepartment of Orthopaedics, University College London Hospital, London, UK; and zUniversity of Teesside, School of Health and Social Care, Middlesbrough, UK. Submitted June 1, 2010; accepted April 27, 2011. The Conflict of Interest statement associated with this article can be found at doi:10.1016/j.arth.2011.04.046. Reprint requests: Raymond Pollock, PhD, MPH, Gledsnest, Hawick, TD9 0LF, UK. © 2011 Elsevier Inc. All rights reserved. 0883-5403/0000-0000$36.00/0 doi:10.1016/j.arth.2011.04.046 1 The Journal of Arthroplasty Vol. 00 No. 0 2011