It represents late sequelae of lipodermatosclerosis where the skin has lost its nutrient blood flow. Lipodermatosclerosis,  an indurated plaque in the medial malleolus. Malignancy, malignant degeneration being a rare but important complication of venous disease since tumors that develop in the setting of an ulcer tend to be more aggressive. Pain, a feature of venous disease often overlooked and commonly undertreated. Anxiety
Depression
Inflammation
Cellulitis

Causes
The most common cause of chronic venous insufficiency is reflux of the venous valves of superficial veins. This may in turn be caused by several conditions:

Deep vein thrombosis (DVT), that is, blood clots in the deep veins. Chronic venous insufficiency caused by DVT may be described as postthrombotic syndrome. DVT triggers an inflammatory response subsequently injuring the vein wall. Superficial vein thrombosis. Phlebitis
May–Thurner syndrome. This is a rare condition in which blood clots occur in the iliofemoral vein due to compression of the blood vessels in the leg. The specific problem is compression of the left common iliac vein by the overlying right common iliac artery. Many May-Thurner compressions are overlooked when there is no blood clot. More and more of them get nowadays diagnosed and treated (by stenting) due to advanced imaging techniques.Deep and superficial vein thrombosis may in turn be caused by thrombophilia, which is an increased propensity of forming blood clots.Arteriovenous fistula (an abnormal connection or passageway between an artery and a vein) may cause chronic venous insufficiency even with working vein valves.
References
Further reading
Group A Streptococcal Infections - National Institute of Allergy and Infectious Diseases
Wilkins, Lippincott Williams & (2004-01-01). Rapid Assessment: A Flowchart Guide to Evaluating Signs and Symptoms. Lippincott Williams & Wilkins. ISBN 9781582552729. == External links ==