Assessment of Swelling, Function, and Pain Following the Tourniquet Use in Total Knee Arthroplasty.

Tourniquet is frequently used during total knee arthroplasty (TKA); however, its use is associated with increased pain, reduced function, and increased swelling in the early postoperative period. This study aims to evaluate the effects of tourniquet application on swelling, pain, knee function, and patient-reported outcomes. This nonrandomized single-center observational clinical trial included 84 primary TKAs, with assessment of tourniquet duration (minutes) and tourniquet pressure (mmHg). Swelling was quantitatively assessed through multiple circumferential measurements of the leg. Secondary outcome included pain intensity, knee flexion, and the Western Ontario and McMaster Universities Osteoarthritis Index score. Outcome was measured at multiple time points before TKA until 6 weeks after TKA. Overall swelling was less at 5 days (3.9 ± 0.75 L vs. 4.7 ± 1.0 L; p = 0.004) with low tourniquet pressure. The level of pain after surgery was lower in the tourniquet cementation group both at 2 days (2.9 ± 2.1 vs. 4.7 ± 2.5, p = 0.01) and at 5 days (2.7 ± 2.1 vs. 4.2 ± 2.5, p = 0.02) after surgery. Active knee flexion at 5 days after surgery was less with longer tourniquet application (65.4 ± 16.4 vs. 74.4 ± 16.7, p = 0.04). We recommend keeping the tourniquet cuff pressure around the thigh below 300 mm Hg to reduce swelling of the whole leg in the early postoperative period after TKA. Tourniquet duration should be kept as low as possible, ideally only during the cementation period, resulting in clinically relevant decreased postoperative pain and increased postoperative knee range of motion. In cases that require higher tourniquet pressures or longer duration of tourniquet, complete recovery from all negative effects can be expected at 6 weeks following TKA. The study provides therapeutic level III evidence.