Negative pressure intrusion cementation versus tourniquet use in total knee arthroplasty: optimising cement mantle thickness

Avoidance of tourniquet in total knee arthroplasty (TKA) has been shown in some studies to be associated with less serious adverse events (SAEs) than use of a tourniquet. Concerns about inadequate cementation leads to some surgeons using a tourniquet, to avoid implant failure from aseptic loosening. Negative pressure intrusion cementation (NPI) is an alternative technique to remove blood from the surgical field. It is unknown whether using NPI and no tourniquet gives a comparable cement mantle thickness (CMT) to TKA surgery with a tourniquet.

This retrospective study compared two techniques for reducing blood during cementation in primary TKA–NPI vs. tourniquet—at a single centre (2016–2023). After screening 353 patients, 80 patients with adequate postoperative radiographs were included. CMT was measured in six zones according to a modified Knee Society Scoring System, creating a cumulative score for each patient. The Mann–Whitney U test was used to compare groups (non-parametric data), and the Intraclass Correlation Coefficient (ICC) was used to measure inter- and intra-observer reliability.

There was a significant difference in CMT in favour of the group with NPI vs. tourniquet (median 12.43 mm vs. 10.67 mm, U = 596, p = 0.05), with a small effect size (r = 0.2). Inter- and intra-observer reliability were good and excellent respectively.

This retrospective cohort study identified a small increase in cumulative CMT in primary TKA using NPI without tourniquet use compared with tourniquet use alone. This technique warrants further study to confirm its clinical significance and relationship to aseptic loosening.