The lymphatics form part of your immune system, helping to deal with infection at a local level but just as importantly, they are responsible for cleansing your tissues and maintaining a balance of fluids in your body. It can be likened to a waste disposal system, taking tissue fluid, bacteria, proteins and waste products away from the tissues around skin, fat, muscle and bone.
Once inside the lymphatic vessels, the tissue fluid becomes known as ‘lymph’ and it is then transported in one direction, by increasingly larger and deeper lymphatic vessels. Movement of lymph depends on muscle movement and the contraction of the deeper vessels themselves.
At some point in its journey, lymph will pass through a lymph node, or gland. Clusters of these nodes are found in the neck, armpits and groins. It is here that the lymph is filtered and cleansed, so that the waste matter, bacteria and harmful cells can be identified and removed by the body’s defense system. Having passed through these nodes, lymph finally drains back into the large veins of the body. From here it travels in the blood back to the heart and is eventually removed from the body as urine through the kidneys.

Lymphoedema refers to tissue swelling caused by an accumulation of protein-rich fluid that’s usually drained through the body’s lymphatic system. It most commonly affects the arms or legs, but can also occur in the chest wall, abdomen, neck and genitals. It is called primary lymphoedema when the lymphatic system either is affected by a hereditary condition or a congenital abnormality. Secondary lymphoedema is linked to damage to lymphatic vessels and/or lymph nodes.

Three gene mutations have been linked with primary lymphoedema:

• FOXC2 – lymphoedema-distichiasis syndrome
• VEGFR-3 – Milroy’s disease
• SOX18 – hypotrichosis-lymphedematelangiectasia syndrome.

• Cancer. If cancer cells block lymph vessels, lymphoedema may result. For instance, a tumor growing near a lymph node or lymph vessel could enlarge enough to block the flow of the lymph fluid.
  Radiation treatment for cancer. Radiation can cause scarring and inflammation of lymph nodes or lymph vessels.
• Surgery. In cancer surgery, lymph nodes are often removed to see if the disease has spread. However, this doesn’t always result in lymphedema.
• Parasites. In developing countries in the tropics, the most common cause of lymphoedema is infection with threadlike worms that clog the lymph nodes.
• Trauma and soft tissue damage
• Venous disease
  Immobility and dependency
  Obesity

• Persistent swelling in the affected limb or area, often causing clothes, shoes, or jewelry to feel tighter than usual.
• A sensation of heaviness, tightness, or fullness in the affected region.
• Discomfort or aching in the swollen area.
• Reduced mobility or difficulty moving the affected limb.
• Pitting edema, where pressing on the skin leaves a temporary indentation.
• Thickening or hardening of the skin, leading to a tougher texture.