Synovectomy during total knee arthroplasty: a pilot single-centre randomised controlled trial.

Background: Total knee arthroplasty (TKA) is an effective procedure for late-stage osteoarthritis (OA) of the knee; however, up to 20% of patients remain dissatisfied. In some patients, this may be due to residual inflammation of the synovium. Our aim was to perform the first randomised controlled trial (RCT) of synovectomy during TKA for patients with macroscopically inflamed synovium. The main objectives were to assess recruitment rates, protocol adherence and outcomes relating to safety such as haemoglobin decrease and adverse events. We also collected data on patient-reported outcomes.

Methods: We performed a single-centre pilot RCT. Patients with a macroscopically inflamed synovium were randomised to receive synovectomy versus a control group that did not undergo synovectomy. We determined feasibility by measuring patient enrolment, completeness of follow-up, and safety via haemoglobin decrease and documentation of adverse events.

Results: We screened 360 patients with 260 deemed ineligible or could not be recruited. From the 100 eligible patients, 54 were enrolled and 40 progressed through to randomisation. All made it to the 12-month follow-up, indicating good protocol adherence. There were no major differences in adverse events or haemoglobin decrease demonstrating acceptable safety. Outcomes relating to satisfaction were reliably obtained.

Conclusions: Patients with macroscopically inflamed synovium of the knee who are due to undergo TKA can be reliably recruited to a randomised trial and synovectomy can be performed safely. A large number is needed to be screened to identify eligible participants, and therefore, a multi-centre trial would be required to assess whether routine synovectomy would improve outcomes in these patients.

Trial Registration: ISRCTN, ISRCTN31010214. Registered 6 October 2016-retrospectively registered.