When to use a tourniquet in primary total knee arthroplasty? A systematic review and meta-analysis

This study aimed to investigate the optimal timing strategy for tourniquet use in primary total knee arthroplasty (TKA).

A systematic search of PubMed, EMBASE, Web of Science, and the China National Knowledge Infrastructure was conducted to identify randomized controlled trials published up to January 2023. The included studies compared the use of a tourniquet solely during cementation (specific-duration tourniquet, SDT) vs. its use throughout the majority of the surgical procedure (majority-duration tourniquet, MDT). MDT was defined as tourniquet inflation prior to the surgical incision and deflation only after the cement had hardened. Continuous variables were pooled using the weighted mean difference (WMD), and relevant subgroups were analyzed independently.

Six studies involving 358 patients (386 knees) were included and assigned to either the SDT or MDT group. Meta-analysis showed that while the SDT group experienced higher intraoperative blood loss [WMD = -68.62, 95% confidence interval (CI): (-93.72 to -43.52), P < 0.001], there was no increase in total blood loss (P = 0.82). The SDT technique did not increase operative time (P = 0.16), yet it improved the postoperative knee visual analog scale scores [WMD = 0.77, 95% CI: (0.31-1.23), P = 0.001] and knee range of motion (ROM) 3 days postoperatively [WMD = -6.69, 95% CI: (-9.29 to -4.08), P < 0.00001]. Meanwhile, no significant difference in ROM was observed between the groups 2 weeks postoperatively (P = 0.31). Finally, the SDT group was associated with a decreased risk of postoperative complications [risk ratio2.77; 95% CI: (1.04-7.43); P = 0.04].

The SDT strategy may be associated with a reduced risk of postoperative complications and accelerated early functional recovery compared to the MDT strategy in primary TKA. Therefore, tourniquet application during SDT appears to be the optimal timing for primary TKA.