TKR without tourniquet: A laboratory study investigating the quality of the tibial cement mantle when using metaphyseal suction and cement gun

PurposeThe majority of cemented knee replacements worldwide are performed with a tourniquet. The benefits of surgery in TKR without a tourniquet have been well described but questions have been raised about the ability to prepare the bone for cementation, and take up of a tourniquet-less technique has been slow. A laboratory based model was constructed to directly compare the quality of cementing between tourniquet and tourniquet-less knee replacement supplemented by metaphyseal suction and a cement gun.MethodsA Sawbone model to represent the metaphyseal proximal tibia was constructed. The model allowed the inflow of simulated blood and the use of metaphyseal suction. The study compared four different techniques; the use of a tourniquet, no tourniquet, no tourniquet with cancellous suction and no tourniquet with cancellous suction and a cement gun. Each subtype of experiment was repeated 5 times. Quality of cementation was assessed using a calibrated engineering planimeter.ResultsThis model has shown that combining the use of metaphyseal suction and a cement gun but without the use of a tourniquet offers significantly better cement penetration (p < 0.0001) than cementing using a tourniquet alone.ConclusionsThis study offers further in vitro evidence to the argument that tourniquet-less surgery when supplemented by appropriate techniques can achieve a good cement–bone interface, whilst avoiding the additional risk of using a tourniquet to perform the procedure.