BACKGROUND: Pneumatic tourniquet can reduce the amount of bleeding during operation, but simultaneously, pneumatic tourniquet will bring perioperative adverse reactions. It is still controversial whether to use a pneumatic tourniquet during total knee arthroplasty. OBJECTIVE: To evaluate the effect and safety of pneumatic tourniquet in total knee arthroplasty. METHODS: We searched PUBMED, EMBASE, the Cochrane Library, CNKI, Wanfang before July 2017 for randomized controlled trials regarding the effect of pneumatic tourniquet in total knee arthroplasty. Data were extracted and analyzed by using Revman 5.3 software.RESULTS AND CONCLUSION: Totally 18 studies were included. Meta-analysis suggested that the use of pneumatic tourniquet could reduce the total amount of blood loss in the total knee arthroplasty, shorten operation time, but could increase postoperative pain and thrombosis incidence (P < 0.05). There was no statistically significant difference in HSS score and range of motion of the knee at 7 days after operation (P > 0.05). These results confirm that the use of a pneumatic tourniquet in total knee arthroplasty can reduce the total blood loss, shorten the operation time, but have no effect on knee function 7 days after total knee arthroplasty, but will increase postoperative pain and thrombosis incidence.

BACKGROUND: Role of Wnt/β-catenin signaling pathway in the pathogenesis of osteoarthritis has been proved by numerous animal experiments and human specimen trials. Wnt/β-catenin signaling pathway and matrix metalloproteinase 13 (MMP-13) play important roles in pathological process of osteoarthritis, and they may be related with each other. OBJECTIVE: To detect the expression levels of β-catenin and MMP-13 in the synovial tissue of osteoarthritis, and to investigate the relationship between β-catenin and MMP-1 in the pathogenesis of osteoarthritis. METHODS: Synovial tissues were obtained from the 54 patients undergoing total knee arthroplasty or knee arthroscopic diagnosis and treatment surgery and 12 healthy patients suffering from amputation caused by trauma. The samples were divided into non-, mild-, medium-and severe-osteoarthritis groups based on advanced Mankin scores. The expression levels of β-catenin and MMP-13 in the synovial tissues were detected by immunohistochemistry, and correlation analysis was conducted. RESULTS AND CONCLUSION: Immunohistochemistry results showed that MMP-13 was negative in the non-osteoarthritis group, positive in 5 (50%) samples in the mild-osteoarthritis group, positive in 11 (65%) samples in the medium-osteoarthritis group and positive in 23 (85%) samples in the severe-osteoarthritis group. β-Catenin was positive in 1 (8%) sample in the non-osteoarthritis group, positive in 7 (70%) samples in the mild-osteoarthritis group, positive in 14 (82%) samples in the medium-osteoarthritis group and positive in 25 (93%) samples in the severe-osteoarthritis group. The expression levels of β-catenin and MMP-13 in the synovial tissues presented a positive correlation (r=0.806, P ＜ 0.001), and the levels increased with joint degeneration becoming severe. These results imply that there is a significant increase in the expression levels of β-catenin and MMP-13 in the synovial tissues of osteoarthritis compared with the non-osteoarthritis group, and β-catenin and MMP-13 exert effects in development of osteoarthritis. Beta-catenin and MMP-13 are closely associated with pathological changes such as cartilage degeneration and synovial inflammation, thus providing new theoretical direction and experimental basis for targeted gene therapy of osteoarthritis.