What is the likely underlying cause of a pulmonary thromboembolism in a patient with a recent ankle fracture?

• A. Venous stasis
• B. Hypercoagulability
• C. Endothelial injury
• D. Multiple risk factors

Answer: (A)

Pulmonary thromboembolism (PE) related to a recent ankle fracture often arises due to venous stasis. When an individual experiences a lower extremity injury, such as an ankle fracture, immobilization or reduced mobility can occur. This lack of movement diminishes blood flow in the veins of the legs, leading to stagnation or pooling of blood. Venous stasis is a significant factor that contributes to the formation of deep venous thrombosis (DVT), which can subsequently dislodge and cause a thromboembolism in the lungs.

While hypercoagulability and endothelial injury can contribute to thrombus formation, venous stasis is particularly relevant in the context of a fracture and subsequent immobilization. It is important to consider that in many cases, multiple risk factors can interplay, but the immediate cause linked to the immobilization following an ankle fracture is primarily venous stasis. Therefore, understanding the mechanisms of stasis in immobilized patients helps clarify the heightened risk of pulmonary emboli in this scenario.