Functional factors , namely failure of the venous calf pump to work efficiently. This may be due to loss of muscle function, pain associated with movement or apathy. Vessel incompetence caused by damage to the valves of the veins. This is often the result of deep vein thrombosis and has a tendency to affect the perforating veins of the leg. Pathophysiology Venous insufficiency has effects on both the dermal and epidermal components of the skin.
Dermal effects are a direct vascular problem.
A decrease in venous return results in venous hypertension. In response to this, surrounding vessels dilate and become more permeable, leading to the lymphatics being overwhelmed. The consequence is oedema which impairs the normal nutritional exchange between capillaries and cells. Epidermal effects see oedema accumulate and cells become swollen and separate. Repair processes result in irregular thickening of the epidermis, with the stratum corneum ill formed.