DRAINAGE VERSUS NON-DRAINAGE IN PRIMARY TOTAL KNEE ARTHROPLASTY WITHOUT TOURNIQUET: A PROSPECTIVE RANDOMISED CONTROLLED TRIAL

Purpose Recently many authors have questioned the role of tourniquets in primary knee arthroplasty (TKA). Meanwhile, whether the use of an intra-articular wound drainage is an advance over the lack of a drain in TKA is controversial in the literature. This study aimed to investigate the efficacy and safety of drainage or not in TKA without a tourniquet. Methods Eighty participants who underwent primary unilateral TKA were prospectively enrolled and were randomized to one of two techniques during surgery without a tourniquet: drainage (Group A) or non-drainage (Group B). Blood loss was monitored perioperatively. The operating time, allogeneic blood transfusion rate, thigh pain, knee pain, limb swelling, clinical outcome as measured by the hospital for special surgery (HSS) score, the ability to straight-leg raise, visual analog scale (VAS) in pain, length of stay and knee active range of motion (ROM) were also recorded. The digital radiographs taken at 6 months postoperatively were assessed for cement mantle thickness and radiolucency using the Knee Society radiographic zones. Results The mean Haemoglobin levels on day one and three postoperative were significantly higher in Group B (112.1±10.6 mg/dL, 99.5±9.6 mg/dL) than in Group A (106.1±12.4 mg/dL, 92.7±13.1 mg/dL) (P=0.026, P=0.011). Blood or blood product transfusion was necessary for thirteen patients in Group A (33.3%) whereas five patients of Group B (13.1%) were in need of blood products, the difference was significant (P=0.036). The total blood loss in Group A was significant more than Group B (597.7 ± 331.6ml vs. 496.1 ± 260.8ml, P=0.012). Among the patients in Group B, haemarthrosis developed in 3 knees (7.9%, P=0.23). Calf circumference measurements of both groups showed a significant difference at postoperative day one (3.2% vs. 5.6%, P = 0.012) as well as day two (4.9% vs. 7.1%, P = 0.07). A superficial wound infection was detected within 3 months after surgery in 3 knees (7.6%) in Group A, whereas no superficial wound infection was observed in Group B, the difference between groups did not reached statistical significance (P=0.248). The difference in VAS score of knee active pain between groups on postoperative day three, five and three weeks were statistically significant (P=0.012, P=0.003, P=0.008). There were no differences in terms of surgical time, thigh/knee rest pain scores, discharge/post-op three weeks HSS score, range of motion, ambulation time, straight-leg raising rate, knee/ thigh circumference, length of stay, cement mantle thickness, or the presence of radiolucency. Conclusions Drainage does not exhibit substantial advantages in promoting post-operative rehabilitation after uncomplicated TKA, compared with non-drainage. On the other hand, it might increase blood loss and wound complication. Therefore, we believe that it is safe and beneficial for our patients to routinely perform uncomplicated TKA without a postoperative drain if the procedure is done without a tourniquet. On condition that prolonged operation time, multiple extra bone cutting, operative outside joint capsule, we still recommend placing a drainage tube.