Lymphology Association of North America (LANA) Practice Exam

What is "rubor of dependency"?

1. Venous ulceration caused by dependency

2. Muscle pain in a dependent position

3. A non-invasive test to assess lymphatic flow

4. A non-invasive test to assess vascular compromise

The correct answer is: A non-invasive test to assess vascular compromise

Rubor of dependency is a clinical sign that involves observing the color changes in the skin of a limb when it is moved from a supine (lying down) position to a dependent (hanging down) position. When the limb is elevated, it receives reduced blood flow and appears pale. When it is allowed to hang down, increased blood flow can lead to a reddish hue or rubor, hence the term "rubor of dependency." This phenomenon primarily assesses vascular integrity and identifies potential blood flow issues that could indicate vascular compromise. The observation of rubor can help distinguish between arterial and venous pathology by showing how blood supply changes in response to positioning. In contrast to a focus on lymphatic flow or pain associated with muscle, the key aspect of rubor of dependency revolves around understanding vascular health. It serves as a useful non-invasive test to assess how well blood is circulating to the distal limb tissues, which is critical in identifying conditions such as peripheral arterial disease or venous insufficiency.