Deep venous thrombosis is caused by all EXCEPT: March 2013 (a, e)
## Core Concept
Deep vein thrombosis (DVT) is a condition characterized by the formation of a blood clot in a deep vein, typically in the legs. The pathophysiology of DVT involves **Virchow's triad**, which consists of blood flow changes (stasis or turbulence), hypercoagulability, and endothelial injury.
## Why the Correct Answer is Right
The correct answer, option , is associated with factors that do not contribute to the development of DVT. To understand why, we need to consider what factors actually contribute to DVT. These include prolonged immobilization (stasis), cancer, and genetic predispositions to hypercoagulability (e.g., Factor V Leiden).
## Why Each Wrong Option is Incorrect
- **Option A:** Prolonged immobilization leads to stasis of blood, which is a component of Virchow's triad and increases the risk of DVT.
- **Option B:** Cancer can lead to a hypercoagulable state, increasing the risk of DVT.
- **Option D:** Genetic factors, such as Factor V Leiden mutation, lead to a hypercoagulable state.
## Clinical Pearl / High-Yield Fact
A key clinical pearl is that **immobilization**, **cancer**, and **hypercoagulable states** are classic risk factors for DVT. Remembering these can help in identifying patients at high risk.
## Correct Answer Line
**Correct Answer: .**