Does the Use of a Tourniquet Influence Five-Year Outcomes Following Total Knee Arthroplasty?

Background: A tourniquet is commonly used during total knee arthroplasty (TKA) to improve surgical field visibility and minimize blood loss. While the short-term effects of tourniquet use on postoperative outcomes have been studied extensively and found to be minimal, its influence on longer-term outcomes remains underexplored. This study examined tourniquet use in TKA with up to five-year follow-up.

Methods: In this post hoc analysis of a randomized controlled trial, 227 patients who underwent primary TKA in the tourniquet (T) group (n = 112) or no tourniquet (NT) group (n = 115) were evaluated. Clinical outcomes and patient-reported outcome measures (PROMs) were compared between the two groups.

Results: The T group had non-significant trends toward reduced blood loss (131.8 versus 116.7 ml, P = 0.098) and shorter operative time (97.8 versus 95.7 minutes, P = 0.264), with slightly higher postoperative day-one Visual Analog Scale (VAS) pain scores (3.1 versus 3.6, P = 0.197). Length of stay (2.0 versus 2.1 days, P = 0.837) and home discharge rate (88.7 versus 92.0%, P = 0.340) were comparable. The NT group had three 90-day readmissions, while none occurred in the T group (2.7 versus 0%, P = 0.081). The active range of motion at the final follow-up was similar between groups (108.3 versus 106.5 degrees, P = 0.457). All-cause revision rates at five years were comparable between the NT and T groups (5.2 versus 3.6%, P = 0.546). Kaplan-Meier survivorship analysis revealed comparable aseptic implant survival at five years (P = 0.769). There were no significant differences in Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR), Patient-Reported Outcomes Measurement Information System (PROMIS) pain intensity, PROMIS pain interference, or PROMIS physical health scores at three months, one year, and five years postoperatively.

Conclusion: Using a tourniquet during primary TKA was not associated with differences in clinical or patient-reported outcomes at up to five-year follow-up. These findings suggest that tourniquet use in TKA can be left to the surgeon's discretion.