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

BACKGROUND: Tourniquet is frequently used during total knee arthroplasty (TKA), however it's use is associated with increased pain, reduced function and increased swelling in the early postoperative period. QUESTIONS/PURPOSES: This study aims to evaluate the effects of tourniquet application on swelling, pain, knee function and patient reported outcome. METHODS: This non-randomized 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 (WOMAC) score. Outcome was measured at multiple time points before TKA until six weeks after TKA. RESULTS: Overall swelling was less at five days (3.9 l ± 0.75 l vs. 4.7 l ± 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 two days (2.9 ± 2.1 vs. 4.7 ± 2.5, p=0.01) and at five days (2.7 ± 2.1 vs. 4.2 ± 2.5, p=0.02) after surgery. Active knee flexion at five days after surgery was less with longer tourniquet application (65.4 ± 16.4 vs. 74.4 ± 16.7, p=0.04). CONCLUSION: We recommend keeping tourniquet cuff pressure around the thigh below 300 mmHg 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 six weeks following TKA.