RESUMEN
PURPOSE: The purpose of the study was whether the use of a tourniquet increases cement mantle thickness in primary total knee arthroplasty and influences the calculated blood loss and postoperative pain. METHODS: Ninety patients with a primary total knee arthroplasty (TKA) were enroled in this prospective randomised trial and divided into a group with (n = 45) and without tourniquet (n = 45). The radiological tibial cement mantle thickness was evaluated postoperatively in four zones on anteroposterior and two zones on lateral radiographs, and values were cumulated. Additionally, the calculated blood loss and postoperative pain levels were recorded. RESULTS: There was a median cumulative cement mantle thickness of 13 mm (range 8-19 mm) without tourniquet and of 14.2 mm (range 9-18 mm) with tourniquet (p = 0.009). The median calculated blood loss was 0.6 L (range 0.2-2.0 L) without and 0.9 L (range 0.3-1.5 L) (p = 0.02) with tourniquet. Patient-reported postoperative pain levels were significantly higher in the tourniquet group during mobilisation (p = 0.01) and at rest (p = 0.001). CONCLUSIONS: The use of a tourniquet in primary TKA increased the tibial cement mantle thickness but also increased the postoperative calculated blood loss and postoperative pain. Surgeons might take this into consideration for decision-making whether to use a tourniquet during TKA. LEVEL OF EVIDENCE: II.