The effect of tourniquet use on fixation quality in cemented total knee arthroplasty a prospective randomized clinical controlled RSA trial

BackgroundA concern that arises with any change in technique is whether it affects the long-term implant stability. The objective of this study was to evaluate the early migration, measured by radiostereometric analysis (RSA), and the functional outcome of the Triathlon™ cemented knee prosthesis, operated on with or without a tourniquet. During the last decades RSA has emerged as a way to assess prosthetic fixation and long time prognosis. The method has been used extensively in both hip and knee arthroplasty.MethodThis was a single centre prospective study including 60 patients randomized into two groups operated on either with or without tourniquet. RSA investigation was done within 2–3 days postoperatively after full weight bearing, and then at 3 months, 1 year and 2 years postoperatively.ResultsThere were no differences between the groups regarding the translation along or rotation around the three coordinal axes, or in maximum total point motion (MTPM). At 2 years the mean MTPM (SD) was 0.71 mm (0.64) for the tourniquet-group and 0.53 mm (0.21) for the non-tourniquet-group.ConclusionsThe tibial tray of the Triathlon™ cemented knee prosthesis showed similar early stability whether operated on with or without tourniquet.Level of evidenceLevel I.Article summaryArticle focus: A safety study for total knee replacement operated on with or without perioperative tourniquet regarding the prosthetic fixation.Strengths and limitations: Strength of this study is that it is a randomized prospective trial using an objective measuring tool. The sample size of 25–30 patients is reportedly sufficient for the screening of implants using RSA (1–3).Trial registration: Clinical trials NCT01604382, Ethics Committee approval D-nr: 144/20085.