Venous stasis
ulcer is a partial or full thickness wound on
the lower extremities often over the malleolus,
caused by venous insufficiency, local stasis,
edema and resulting ischemia. Venous
ulcers occur when the superficial leg veins
become dilated from inadequate valve function,
leading to stasis and venous hypertension.
There are several theories as to
the etiology and the difficulty of healing:
Calf venous pump
failure
Peri-capillary
fibrin cuffs which impairs oxygen diffusion to
the wound
Macromolecules
like fibrinogen leak into the dermis due to
the venous hypertension, and trap GROWTH
FACTORS and MATRIX PROTEINS making them
unavailable for the repair process
Decrease in
nutritive skin capillary blood flow
Ulcer wound
fluid impeding GROWTH FACTOR function and cell
proliferation
combination of
all the above.
Incidence:
Venous ulcers account
for over 70% of chronic leg ulcers with the
incidence increasing with age. The prevalence in
the adult population either active or healed is
about 1-2%.
Characteristics:
The classic presentation is an
irregularly shaped wound with well defined borders
surrounded by erythematous or hyperpigmented skin.
A yellow to white exudate is commonly observed. The
lower leg is typically edematous. Varicosities are
often present, and a dilated vein may be near the
base of the ulcer. The surrounding skin change is
known as lypodermatosclerosis. This process is
caused by chronic changes in the soft tissue from
edema and inflammation. The skin is often tender
and can be mistaken for infection.
Figure 4:
Venous Stasis Ulcer
Note
full thickness nature of the ulcer with well
defined borders surrounded by the chronic skin
changes.
