Perioperative Blood Loss in Cementless Versus Cemented Total Knee Arthroplasty With Local Tranexamic Acid Administration.

BACKGROUND

Cementless total knee arthroplasty (TKA) has historically been associated with greater perioperative blood loss than cemented TKA. Whether a standardized local-only tranexamic acid (TXA) regimen can mitigate this difference remains unclear.

OBJECTIVE

To compare perioperative blood loss between cementless and cemented TKA under a standardized local-only TXA protocol in a retrospective cohort, focusing on comparison rather than causation. Secondary outcomes included perioperative hemoglobin (Hb)/hematocrit (Hct) changes (preoperative to postoperative day (POD) 1), intraoperative and perioperative blood loss, transfusion, POD 7 D-dimer, operative time, and complications.

METHODS

We retrospectively reviewed 103 consecutive unilateral primary TKAs performed at a single center (cementless, n=55; cemented, n=48) between 2013 and 2020. A standardized local TXA protocol was used in all cases (1 g periarticular before implantation and 1 g intra-articular before closure); no drains were used. Outcomes included operative time, perioperative Hb/Hct change, intraoperative blood loss, total perioperative blood loss estimated by the Gross formula, transfusion, complications, and POD 7 D-dimer. Group comparisons used t-tests with Welch's correction or Mann-Whitney U tests, and Fisher's exact tests for categorical variables.

RESULTS

Baseline demographics were comparable between groups. Intraoperative blood loss was similar (cementless 91.4 ± 75.1 mL vs cemented 85.5 ± 111.2 mL; p=0.140), as was perioperative blood loss (154.3 ± 76.9 mL vs 132.9 ± 91.0 mL; p=0.204). No patient required transfusion. POD 7 D-dimer was higher in the cementless group (9.7±4.1 µg/mL vs 7.8±4.4 µg/mL; p=0.002), but no symptomatic venous thromboembolism occurred. Two late surgical-site infections in the cementless group resolved without revision or loosening; no wound complications occurred in either group.

CONCLUSIONS

Under a standardized local-only TXA protocol, cementless TKA achieved perioperative blood loss comparable to cemented TKA without increasing symptomatic thromboembolic events. These findings suggest the feasibility of a standardized local TXA protocol for cementless TKA. Importantly, fixation method was fully collinear with implant design (cementless: low contact stress (LCS) limited-box; cemented: posterior-stabilized (PS) open-box), and femoral box geometry can influence bleeding; therefore, results should be interpreted within this implant- and protocol-specific context.