Importance of knowing the causes of leg swelling-By Dr Harold Gunatillake This is a common condition that is most prevalent in your 60s and over. If you observe the condition you may need to see your health provider for investigation and treatment. Swelling can occur in one leg and foot, or both. If one limb is involved the cause is local in the leg itself, such as lymphatic gland blockage near the groin, blood vessel blockage due to deep vein thrombosis (DVT), skin infections, cellulitis and so on. Deep vein thrombosis is a serious condition that occurs when blood clots form in the calf and thigh veins. Early detection and treatment are required before a clot moves from the leg into the lung referred to as pulmonary embolism. The commonest cause is when you sit frequently without much leg movements as travelling on a plane, the venous blood flow ...