Lymphedema Anatomy & Physiology
The lymphatic system collects, transports, and filters lymph fluid throughout the body.
Under normal conditions, the human body produces about two liters of lymph fluid every day. Disruption to the lymphatic system impairs its ability to drain fluid properly, resulting in swelling.
Breast cancer is one of the leading risk factors for lymphedema. There are nearly 3 million women in the US with a history of breast cancer.
Source: Surveillance, Epidemiology, and End Results Program – National Cancer Institute
What is the Lymph System?
The lymphatic system consists of lymph collectors, lymph vessels, and lymph nodes. The lymphatic system collects, filters, and concentrates lymph fluid from all over the body and returns it to your blood system. Lymph nodes filter bacteria and other toxins from your body, and also help prevent cancer cells from spreading. Lymph vessels are equipped with many small crude valves and pumping action that helps to transport lymph fluid through your body. Lymph fluid transport is aided by:
- Muscle contractions
- Arterial pulsations
- External compression
- Manual lymphatic drainage
- Short stretch bandages
- Gradient compression garments
How Lymphedema Disrupts the Lymphatic System
Lymphedema occurs when the normal flow of lymph fluid through the lymphatic system is disrupted due to damage to lymph vessels or lymph nodes. When this damage occurs, the body cannot drain the excess fluid and proteins from the area. The fluid then begins to back up and swelling occurs. Lymphedema is most commonly seen in the arms and legs.
Damage to the lymphatic system can occur due to surgery, radiation, a tumor blocking the lymph vessel, or trauma. Additionally, repeated infections can scar the fragile lymphatic vessels and contribute to worsening of the lymphedema.
The accumulation of protein rich fluid in the limb's tissues causes additional problems over time. The protein rich fluid causes your body to send immune cells to try to process and get rid of the excess proteins. Over time, the excess proteins and the associated inflammation can lead to hardening of the skin from fibrosis, as well as enlargement of the limb due to deposition of extra fatty tissue. The proteins and inflammation also increase your risk of developing cellulitis in the limb.