Are current thrombo-embolic prophylaxis guidelines applicable to unicompartmental knee replacement?

Abstract

Symptomatic and asymptomatic deep-vein thrombosis (DVT) is a common complication of knee replacement, with an incidence of up to 85% in the absence of prophylaxis. National guidelines for thromboprophylaxis in knee replacement are derived from total knee replacement (TKR) data. No guidelines exist specific to unicompartmental knee replacement (UKR). We investigated whether the type of knee arthroplasty (TKR or UKR) was related to the incidence of DVT and discuss the applicability of existing national guidelines for prophylaxis following UKR. Data were collected prospectively on 3449 knee replacements, including procedure type, tourniquet time, surgeon, patient age, use of drains and gender. These variables were related to the incidence of symptomatic DVT. The overall DVT rate was 1.6%. The only variable that had an association with DVT was operation type, with TKR having a higher incidence than UKR (2.2% versus 0.3%, p < 0.001). These data show that the incidence of DVT after UKR is both clinically and statistically significantly lower than that after TKR. TKR and UKR patients have different risk profiles for symptomatic DVT. The risk-benefit ratio for TKR that has been used to produce national guidelines may not be applicable to UKR. Further research is required to establish the most appropriate form of prophylaxis for UKR.

Staged venous thromboemolic events prophylaxis with low‐molecular‐weight heparin followed by aspirin is safe and effective after arthroplasty

“…Although the numbers are small, this does imply that bilateral surgery creates a higher risk. These data also indicate that despite the low rate of VTE following UKA reported in this study and previously, 23 fatal PE still occurs after UKA and it is essential to maintain clinical vigilance and adherence to protocol.…”

Changes in Markers of Thrombin Generation and Interleukin-6 During Unicondylar Knee and Total Knee Arthroplasty

“…Of the seven studies we were able to identify, all noted evidence of DVT/PE or lethal PE on follow-up of UKA patients [2, 4–9]. In several, the risk of DVT was lower with UKA than TKA [6, 7]. Others reported a very low rate of DVT (0.1%) and no PE in a series of 828 patients (1000 UKA) [4].…”

“…The operation is of smaller magnitude than TKA based upon the amount of bone preparation and blood loss, presumably triggering less metabolic injury. However, tourniquet times are similar for UKA and TKA, which has raised the debate as to whether the two procedures carry the same thromboembolic risk [5, 6]. A number of studies have been published demonstrating the risk of deep vein thrombosis (DVT)/pulmonary embolism (PE) to be lower with UKA [6, 7] whereas others have noted a similar risk of PE or death from PE [5, 8].…”

“…As such, there is a wide variation in thromboprophylaxis after UKA. Some authors utilize chemoprophylaxis similar to TKA [4–6], others use only mechanical thromboprophylaxis [9], and still others believe that thromboprophylaxis is not necessary after UKA [10]. …”

Is Routine Thromboprophylaxis Needed in Korean Patients Undergoing Unicompartmental Knee Arthroplasty?

“…On the other hand, unicompartmental knee arthroplasty (UKA) is less invasive and has a faster recovery time compared to TKA, and patients undergoing UKA are generally younger and more active compared with patients undergoing TKA. Indeed, the prevalence of symptomatic VTE following UKA in patients receiving routine pharmacological thromboprophylaxis is remarkably lower than that of TKA ( 6 7 8 9 ). However, no gold standard strategy for preventing VTE in patients undergoing UKA has been established, and the optimal aggressiveness of thromboprophylaxis in UKA patients remains a challenging issue ( 8 ).…”