Risk factors for venous thromboembolism following knee arthroscopy: A systematic review and meta-analysis of observational studies

Objectives: To evaluate the risk factors for increased risk of venous thrombosis after arthroscopic knee surgery. Methods: PubMed, EMBASE and Cochrane Library were searched from their inception to April 4, 2023. Observational studies investigated venous thrombosis following arthroscopic knee surgery were included. The Newcastle Ottawa Scale (NOS) was used to evaluate the methodological quality of included studies. The odd ratios (ORs) and 95% confidence intervals (CIs) pertaining to each risk factor were synthesized through a random effects model by STATA 14 software. Results: The protocol this meta-analysis has been registered on PROSPERO (CRD42023410283). A total of 22 observational studies were included in the systematic review, all of which were of moderate or high methodological quality. The results of the meta-analysis revealed that several factors were significantly associated with an elevated risk of venous thrombosis following arthroscopic knee surgery. These factors included age (mean age ≥30 years) [OR = 1.08, 95%CI (1.04, 1.13), P = 0.001], overweight or obesity [OR = 1.31, 95%CI (1.13, 1.52), P＜0.001], oral contraceptive use [OR = 1.90, 95%CI (1.52, 2.37), P＜0.001], and smoking history [OR = 1.35, 95%CI (1.06, 1.71), P = 0.014]. Furthermore, the subgroup analysis indicated that patients with an average age over 50 years [OR = 3.18, 95%CI (1.17, 8.66), P = 0.001] and those who underwent surgery with a tourniquet for ≥90 min [OR = 4.79, 95%CI (1.55, 14.81), P = 0.007] were at a significantly increased risk of venous thrombosis after knee arthroscopy. Conclusion: Age, obesity, oral contraceptives, smoking history, and prolonged tourniquet use may increase the risk of venous thrombosis after arthroscopic knee surgery. The incidence of venous thrombosis after knee arthroscopy is on a downward trend, but due to its severity, increasing awareness of risk factors and implementing effective prophylaxis are important tasks for clinicians to prevent the risk of venous thrombosis after knee arthroscopy.