Abstract:[Objective] To compare the consequence of different pressure strategies of tourniquet in fixed bearing unicompartmentalknee arthroplasty (FB-UKA). [Methods] A prospective single-blind randomized controlled study was conducted on 60 patients who were un-dergoing FB-UKA for knee osteoarthritis in our hospital from July 2022 to July 2023. The patients were randomly divided into the fixed pres-sure(FP) group, limb occlusion pressure (LOP) group and systolic blood pressure (SBP) group, with 20 patients in each group. The clinicaland blood test data were compared among the 3 groups. [Results] All patients in the 3 group had FB-UKA performed successfully. The FPgroup had significantly higher tourniquet pressure than the LOP and SBP groups [(300.0±0.0) mmHg vs (241.2±35.7) mmHg vs (273.1±12.3)mmHg, P<0.001], but the FP group consumed significantly less preparation time of tourniquet than that the LOP group and SBP group [(0)min vs (3.9±0.8) min vs (1.5±0.5) min, P<0.001]. Compared with those 1 day after surgery, the VAS score significantly decreased (P<0.05),whereas the HSS score significantly increased 3 days and 7 days after surgery in all the 3 groups (P<0.05). Compared with that 1 day aftersurgery, the swelling rate of the three groups was significantly increased 3 days after surgery (P<0.05), whereas which significantly decreased7 days after surgery (P<0.05). The FP group proved significantly inferior to the LOP group and SBP group in terms of the VAS score andswelling rate at all corresponding time point after surgery, as well as HSS score 1 and 3 days after surgery, with significant differences (P<0.05). Regarding blood test, the Hb decreased significantly (P<0.05), while Hct remained unchanged significantly 2 days after surgery com-pared with those before surgery (P>0.05). At any corresponding time points, there were no significant differences in Hb value and Hct amongthe three groups (P>0.05). [Conclusion] The strategy of establishing tourniquet pressure based on systolic blood pressure (SBP) and limb oc-clusion pressure (LOP) does achieve more satisfactory outcomesthe than conventional fixed tourniquet pressure in FB-UKA.