Tourniquet use in TKA is common practice. A recent meta-analysis concluded that whilst early release (prior to closure of the quadriceps mechanism) increases blood loss, it protects patients from complications. However, there has been no research evaluating tourniquet use during cement fixation only. This study proposed to establish whether tourniquet application during cement fixation only (Short Duration) was associated with better functional recovery compared to standard tourniquet (Long Duration) application during TKA.

We planned to randomise 230 patients to receive Short or Long Duration tourniquet application. The primary outcomes were in-hospital donor transfusion rate and the Oxford Knee Score at 10 weeks post-surgery. Serial measures (pre-operative, day 4 then 2, 10, 26 and 52 weeks post-operation) of knee range and function were undertaken. Pre- and post-operative Doppler ultrasounds were obtained. The trial was discontinued after randomisation of 65 patients.

Interim analysis indicated the risk of transfusion (odds ratio 7.38, P = 0.015) was higher in the Short Duration group. At 10 weeks post-surgery, no significant difference was observed in Oxford Knee Score. There were no between-group differences in rate of recovery up to 26 weeks for any outcome.

We conclude that restricting tourniquet application to the period of cementing is associated with a significantly higher risk of transfusion. This approach is impractical if it is not offset by very impressive gains in functional recovery.

Rivaroxaban is an oral anticoagulant which has the potential to replace subcutaneous Clexane in post operative prophylaxis of venous thromboembolism following knee replacement. Rivaroxaban has been shown to be at least equivalent to Enoxaparin in the prevention of deep venous thrombosis and pulmonary embolism with a similar rate of major bleeding. However, the morbidity associated with the new product has yet to be fully examined. Our own anecdotal evidence suggests that Rivaroxaban may be associated with poorer knee range of motion, and greater bruising and haemarthrosis. This pilot study aimed to compare these outcomes as well as knee pain and length of hospital stay in patients receiving Rivaroxaban and Enoxaparin following total knee replacement.

A controlled before and after study with single blinding was performed. Patients in the ‘Before’ group were given Rivaroxaban (our current protocol). Patients treated in the “After’ group were subjected to our previous protocol (Enoxaparin). Patients were followed up to 6-weeks post surgery. Blinded assessors reviewed range of motion and wound outcomes using a photographic method. Swelling was measured using a standardized technique. Bleeding, pain and length of stay were prospectively recorded.

Data analysis is due to be completed in April 2011. Complete results will be available after this time. Discussion: Rivaroxaban was introduced to lessen patient burden as oral administration is presumed to be more acceptable than self-injection of Enoxaparin. It is yet to be determined comprehensively whether the benefits of oral administration outweigh any associated risks. Surgeons must carefully consider the risks and benefits of their choice of venous thrombosis prophylaxis following total knee replacement.