Abstract
Tourniquet use in total knee arthroplasty (TKA) is convenient for the surgeon and provides a bloodless field for expeditious surgery and a dry field for cementation, but can best be described as an orthopaedic tradition. It is logical for complex anatomy of ligament, nerve, and vessel surgery but it may not be necessary for TKA. In one recent randomised trial, the absence of the tourniquet was not found to affect the quality of cement fixation. There are numerous potential downsides to the use of a tourniquet including decrease range of motion, delayed recovery, increased pain, wound complications, micro-emboli, neuropathy, and increased VTE. There are also a number of complications associated with the use of a tourniquet including arterial thrombosis, skin irritation below the tourniquet, post-operative hyperemia, blood loss, less accurate intra-operative assessment, and it complicates intravenous drug administration. Studies of range of motion have shown that when there is a difference noted, the range of motion is consistently better without tourniquet use. When a tourniquet is utilised it has been found to be advantageous to only use the tourniquet for a minimal amount of the case, typically when cementing is performed. Functional strength has also been found to be improved without the use of a tourniquet. In a recent randomised trial, tourniquet use was associated with decreased quad strength at 3 weeks that persisted at 3 months. This was attributed to muscle damage, tourniquet-induced ischemia, and compressive injury. Increased peri-operative pain has also been reported in randomised trials associated with the use of a tourniquet. Edema, swelling, and limb girth issues have also been noted to be associated with tourniquet use. Exsanguinating a limb will result in swelling approximately 10% of the original volume half due to a return of blood, and half due to reactive hyperemia. Longer tourniquet times are also associated with increased wound drainage and more wound hypoxia as measured by transcutaneous oxygen levels. Tourniquet use has also been associated with embolic phenomenon with several times greater risk of large emboli. In one study where quantitative MRI was utilised on both thighs after unilateral total knee replacement with and without a tourniquet, the tourniquet group showed more atrophy with a loss of 20% of the volume compared to the normal side in total knees performed with a tourniquet which also performed clinically worse. There is a small but substantial risk of arterial thrombosis particularly in patients that have atherosclerotic plaque. Ironically there is a risk of increased post-operative blood loss due to the post-tourniquet “blush” as the blood pressure and pain increase hours after a surgical procedure is completed. There is also difficulty in identifying and coagulating posterior and lateral geniculate vessels with the components in place. Utilizing a tourniquet also interferes with intra-operative assessment of patella tracking, range of motion, ligament stability, and gap balancing. Randomised clinical trials have concluded that there is less pain and quicker recovery without the use of a tourniquet. There have also been reports of less swelling, increased range of motion, less analgesic use and better clinical outcome when a tourniquet is not utilised. A meta-analysis of systematic reviews favored not utilizing a tourniquet due to the decrease in complication rate and the improvement in clinical results. While it is standard practice in the US to utilise a tourniquet, the strong consensus of the literature on the subject favors either not using a tourniquet or minimizing the use of a tourniquet for the period of time necessary for a very dry field for cement fixation.
