A tourniquet is often used in total knee arthroplasty (TKA) to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation. On the other hand, the associated risks include skin burns, soft tissue and muscle damage, injury of calcified vessels, increased swelling and stiffness of the joints, nerve injury, paralysis, and thromboembolic events.~The automatic lower limb pneumatic tourniquet system (Zimmer) was applied to reduce blood loss during surgery. The skin under the tourniquet was covered by cast padding. The operated leg was elevated and exsanguinated before inﬂating the automatic pneumatic tourniquet. There are three main strategies for the use of a tourniquet in TKR: A) inflate before incision and deflate following cement hardening ('skin to cement'); B) inflate prior to cement application and deflated following hardening ('cement only'); C) inflate before incision and deflate following completion of skin closure ('skin to skin'). The optimal timing of tourniquet application during primary TKA is still a matter of debate. Most previous reports have failed to show signiﬁcant differences among different tourniquet strategies.~Kvederas et al. compared these three strategies in a randomized double-blind clinical trial, and demonstrated that the estimated blood loss was highest when the tourniquet was inﬂated just before cement application and deﬂated after its hardening ('cement only'), while inﬂation of tourniquet before skin incision and its deﬂation after hardening of cement ('skin to cement') tends to give better early postoperative mobilization. However, this was an interim report with limited number of patients, and only limited outcome parameters were reported, which were insufﬁcient to draw ﬁrm conclusions regarding the differences in outcome.~Therefore we performed this prospective randomized controlled trial (RCT) with a decent sample size to investigate the best tourniquet strategy in TKA. In addition to the blood loss and early postoperative outcomes, we also strictly monitored pain, soft tissue injury, and rehabilitation with a longer follow-up duration up to 6 months.~All of the operations were performed through the medial parapatellar approach by the same experienced joint replacement surgeon. All patients underwent primary TKA with minimally invasive techniques and cemented prostheses (EvolutionTM medial pivot, MicroPort, USA). An intramedullary guide was used for both tibial and femoral cuts.~The automatic lower limb pneumatic tourniquet system was applied to reduce blood loss during surgery. The skin under the tourniquet was covered by cast padding. The operated leg was elevated and exsanguinated before inﬂating the automatic pneumatic tourniquet. One of the three tourniquet treatment strategies was used, as determined by the group allocation of the patient. In all the three groups, the tourniquet was inﬂated to a pressure of 280 mm Hg. The wound was closed after wound irrigation and hemostasis and then was wrapped with elastic bandages. One drainage was applied postoperatively in all patients and was kept until 24h to monitor blood loss.
A tourniquet is often used in total knee arthroplasty (TKA) to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation. On the other hand, the associated risks include skin burns, soft tissue and muscle damage, injury of calcified vessels, increased swelling and stiffness of the joints, nerve injury, paralysis, and thromboembolic events. The automatic lower limb pneumatic tourniquet system (Zimmer) was applied to reduce blood loss during surgery. A prospective randomized controlled trial (RCT) was performed to investigate the best tourniquet strategy in TKA. The participants were randomly allocated to groups with different tourniquet strategies: Group 1) tourniquet inflation from skin to cement hardening (skin to cement); Group 2) tourniquet inflation only from cementation (cement only) and Group 3) tourniquet inflation from skin incision to skin closure (skin to skin). In addition to the blood loss and early postoperative outcomes, pain, soft tissue injury, and rehabilitation were also strictly monitored with a longer follow-up duration up to 6 months.