Comparison of three different tourniquet application strategies for minimally invasive total knee arthroplasty: a prospective non-randomized clinical trial

It is still controversial on the optimal timing of tourniquet used in total knee arthroplasty (TKA). Most previous studies focused on the comparison of different tourniquet application in controversial TKA, while the aim of our work was to compare three strategies of tourniquet application in minimally invasive TKA. 90 patients were enrolled in this study. Based on the different tourniquet application strategies, they were divided into three groups. Group A: using tourniquet during the whole surgery; Group B: tourniquet inflated before incision and deflated after the hardening of the cement; Group C: using tourniquet during the cementation. Blood loss and serum levels of C-reactive protein, IL-6, creatine kinase and myoglobin were checked preoperatively. The HSS knee score, VAS pain score, range of motion (ROM), limb swelling and hospital stays were also recorded. The mean levels of Hb and Hct were lower in Group C (104.2 ± 10.4 g/L, 31.8 ± 3.2 %) than those in Groups A (111.4 ± 14.4 g/L, p = 0.035; 34.1 ± 4.1 %, p = 0.032) and B (112.8 ± 14.3 g/L, p = 0.013; 34.5 ± 3.7 %, p = 0.011) immediately after the surgery. Compared with Groups A and B, both serum inflammation and muscle damage markers were lower in Group C. There were no significant differences between the groups in terms of HSS knee score, ROM, estimated blood loss, swelling ratio, VAS pain score and hospital stays. Using a tourniquet full time in minimally invasive TKA causes less intraoperative blood loss and more excessive inflammation and muscle damage. However, the advantage of part-time using tourniquet did not show in early functional outcomes.