Lipodermatosclerosis is an inflammatory skin condition resulting from underlying venous insufficiency. This is caused by: Incompetent venous valves Venous outflow obstruction Dysfunction of the calf muscle pump. The resulting venous hypertension causes an increase of leukocytes within the veins, which then migrate into surrounding tissue. The leukocytes become activated, attracting and releasing proinflammatory cells and cytokines, inducing a chronic inflammatory state. Increased collagen production leads to the fibrosis of subcutaneous fat.