Which statement best describes the rationale for using a tourniquet in knee arthroplasty and its potential drawbacks?

• A. Increases postoperative pain
• B. Decreases risk of thromboembolism
• C. Improves visualization by reducing blood loss
• D. Has no effect on tissue injury risk

Answer: (C)

Using a tourniquet in knee arthroplasty mainly aims to create a bloodless field by temporarily stopping arterial inflow to the lower leg. This reduction in bleeding gives a clearer surgical view, making bone cuts, alignment, and cement placement more precise and can shorten intraoperative time. That clearer visualization and reduced blood loss is why many surgeons use it.

However, this comes with potential downsides. While the limb is tourniqueted, tissues experience ischemia, which can lead to muscle and nerve irritation or injury, particularly with longer inflation times. After the tourniquet is released, reperfusion can cause a transient surge of metabolites and swelling, contributing to postoperative pain, quadriceps weakness, or delayed rehabilitation. There is also a risk of nerve compression or localized tissue damage from the cuff, and some concerns about wound healing or infection in certain cases. Because the effect on thromboembolism risk is not reliably beneficial, the decision to use a tourniquet is balanced against these potential tissue and recovery considerations.