Effect of postoperative ankle pump exercises on the prevention of deep vein thrombosis and venous hemodynamics following lower limb orthopedic surgery: a meta-analysis of randomized controlled trials.

Background: Deep vein thrombosis (DVT) is a common and serious complication following lower limb orthopaedic surgery. Early ankle pump exercises may promote venous return, reduce limb swelling, and lower the incidence of postoperative DVT. However, the efficacy of such interventions remains inconsistently reported. The aim of this meta-analysis is to evaluate the effects of preoperative and postoperative ankle pump training on DVT incidence and venous haemodynamic parameters, such as maximum venous outflow (MVO) and maximum venous capacity (MVC).

Methods: A systematic Literature search was performed across multiple databases up to July 2025 to identify randomized controlled trials (RCTs) that compared ankle pump exercises with standard care in patients undergoing lower limb orthopaedic surgery. Data were pooled using a fixed-effects model. The outcomes included the incidence of DVT (odds ratio (OR)), MVO, and MVC (standardized mean difference (SMD)). Heterogeneity was assessed using the I² statistic, and the risk of bias was evaluated using the Cochrane Risk of Bias Tool.

Results: A total of 16 RCTs involving 1,704 patients (intervention: n = 889; control: n = 815) were included. Compared with routine care, ankle pump exercises significantly reduced the incidence of DVT (OR = 0.27, 95% CI: 0.20-0.37, p < 0.001; I² = 0.0%, p = 0.523). For MVO, the pooled results from 6 studies revealed a significant improvement in the intervention group (SMD = 0.50, 95% CI: 0.34-0.66, p < 0.001; I² = 7.8%, p = 0.366). MVC also significantly increased following ankle training (SMD = 0.47, 95% CI: 0.31-0.63, p < 0.001; I² = 0.0%, p = 0.915). The risk of bias was low to moderate across the included studies. The funnel plots revealed no significant publication bias.

Conclusions: This meta-analysis provides Level I evidence that ankle pump exercises significantly reduce the incidence of deep vein thrombosis (DVT) and increase venous haemodynamic parameters-specifically maximum venous outflow (MVO) and maximum venous capacity (MVC)-in patients undergoing lower limb orthopaedic surgery. These findings support the integration of ankle pump exercises into routine postoperative care as an effective, noninvasive strategy to mitigate DVT risk and promote venous return.