Canadian Medical Alliance for the Preservation of the Lower Extremity
"Iron rusts from disuse.
Water loses its purity from stagnation."
--Leonardo da Vinci
Humans are approximately 60% water,
but sometimes the water in our bodies
accumulates in areas it shouldn't.
Such is the case with venous ulcers, also
known as stasis ulcers. They develop
because of an excessive accumulation of
fluids in the lower legs.
Venous ulcers may last weeks. They may
last years. And they may be painful.
As seen to the right, venous ulcers are
typically located on the medial (inside)
portion of the of the leg. They are typically
shallow, and often appear with a mix of
yellow, necrotic tissue and a red, granular
A common reason these ulcers form is
improperly-functioning valves in the veins.
Valves exist to prevent back flow of the body's blood towards the feet caused
by gravity. So when the valves fail, fluid accumulates. The fluid stagnation
occurs first in the veins, then as the fluid leaks, in the spaces outside the blood
vessels and cells, a region known as the interstitial space.
To the right we see distended, varicose veins (varicosities). Below are smaller,
"spider" varicosities up close (left) and associated with a resolving wound
Each is caused by a break down of the valves in the veins, causing the blood to
pool or stagnate.
While faulty valves may be the initial cause for the fluid accumulation, sometimes excess fluid in the lower leg develops for a general medical reason. For example, congestive heart failure, kidney disease, liver disease, high salt intake, and low albumin in the blood can all cause edema in the leg.
Edema may also be related to the use of medications like anti-inflammatories, steroids, and calcium channel blockers. They may also be related to diabetic medications like pioglitazone and rosiglitazone and the anti-Parkinson's drug, ramipexole.
The result can be swelling without any visible issues with the veins (below). Note the redness that commonly accompanies leg edema. This is discussed below.
As fluid builds up in the leg, visible distention of the leg develops. It is usually "pitting" in nature. Pitting means that pressure from a finger can result in a depression in the skin that can take several seconds to rebound (below). (Non-pitting edema is classically found with lymphedema.)
Ulcers begin because the increase in fluid stretches the skin, like a balloon
filling with water.
Eventually, the skin can be stretched to the degree that fluid begins to
seep through (yellow arrow, right).
This is the beginning of ulcer formation.
This fluid is typically serous--meaning it's composed of proteins dissolved
in the water. It is typically clear with a yellowish tinge.
In the example below left, we see a swollen foot, again with the serous fluid beginning to seep through the skin (yellow arrow). But as in the examples earlier, we also see a lot of redness. The redness is caused by the stretching of the skin and seepage through the skin causing inflammation. This is known as venous dermatitis.
In addition to the redness of inflammation, the skin may also exhibit scaling, crusting, and itchiness (below right).
If the swelling (edema) is not addressed at this stage, an
ulcer tends to develop and enlarge over time, as seen below.
In the example to the left, note the redness of inflammation in the skin below the wound.
Note, too, the chronic skin changes beginning above the ulceration. It's coarsening. It's thickening. This process is discussed below.
In addition to redness, chronic cases, there may be a
progressive and permanent brown discoloration
develop in the leg called hemosiderin deposition.
This is caused when the lack of blood flow (stasis)
allows blood to leak from the veins into the skin tissue.
Eventually the iron, carried by the hemoglobin in our
red blood cells, is released into the skin and surrounding
In response to the iron spilling into the skin, the body
sends cells known as macrophages to digest the debris.
The resulting product is a dark-brown pigment, a
mixture of iron, sugars and proteins known as
And sometimes a white discoloration occurs. To the lower left we see an active wound nearing resolution. Interspersed within the large red discoloration we see regions of white (white arrow). This is known as atrophie blanche, French for white atrophy. Its presence demonstrates atrophy or withering of the skin. To the lower right we can see atrophie blanche in a healed ulcer. We also see a thickening and coarsening of the skin.
Thickening and Coarsening of the Skin
Below we see more thickening and hardening. This is also known as sclerosis or induration.
Induration is a result of an overgrowth (hyperplasia) or scarring of connective tissues within and below the skin that develops from chronic inflammation.
Treatment of Venous Ulcers
Because venous ulcers are caused by fluid distending the skin, we must first identify the cause of the edema.
Are the ulcers caused simply from incompetent veins?
Or is there a systemic issue at the root of the problem--such as congestive heart failure, kidney disease or liver disease?
If the suspicion is that there may be a general
medical issue, your physician may order a chest
x-ray, an ECG, and blood work.
You may be placed on medications or be referred
to another specialist specific to your specific
When infection is present in the compromised skin,
antibiotics are used.
To treat skin irritations and inflammation, oral or
topical medications like steroids to calm red, inflamed,
scaly and itchy skin.
In the example to the right, a topical steroid
solution was used.
The photo to the right is at three months.
Venous wounds don't typically develop the thick, callus seen in neuropathic wounds, but they are often associated with slough--the yellow, necrotic tissue. Its may delay healing, and it may act as a food source for a bacterial infection.
So it's a good idea to get ride of it. The slough may be removed in a variety of ways, with the aim to prepare a good, granular wound bed.
In the photos below, taken over three months, a chronic, non-responsive wound with painful yellow slough was treated was compression, coupled with enzymatic debridement. You can see the proportion of slough decrease and the proportion of red, granular issue increase over time.
As the necrotic tissue diminishes, and living tissue replaces it, there is more moisture in the wound. The fourth photograph (right) is becoming too macerated (wet), and a more absorbent dressing and more frequent changes should be used at this point. But there is now a good, red, vascular wound bed (right) that is able to heal.
For most ulcers with a venous origin, however, primary
treatment will be directed at controlling the edema.
Treatment will likely include some combination of
compression, elevation of the leg, and diuretics
(medicines that help you excrete fluids).
Compression may be performed with wrapped dressings
These are easily applied, and those that find stockings
impossible to deal with, and they may be effective.
Compression is easily adjusted as well.
But proper compression--with a proper pressure gradient
to move the fluid up and out of the legs--can be difficult
to achieve or maintain with a wrap. So fluid may not move
up and out of the legs well.
Another downside is that constantly replacing the
materials in the compressive wraps can be expensive
over the long term.
Compressive stockings are superior to compressive wraps
in that they achieve more effective compression. They're
tighter at the bottom, a bit less tight further up the leg, and
a bit looser still, higher up the leg (see right).
They can extend up the leg to different levels (below
knee, mid-thigh, for example) and can achieve a variety
of compression levels, both at a prescription and
To the right is a traditional look of a compressive stocking,
with some newer, more modern style options below.
Compressive stockings do come with a downside, however.
They're more expensive up front (though cheaper than
disposable dressings over the long-term). And patients
need more than one pair, as they cannot be thrown in
the dryer or the elastic will fail.
The biggest downside to the stockings is that they can be
difficult to get on, and compliance is an issue.
Dressings applied to the wound are appropriate in many cases,
but when used under compression, they can put more pressure
on the wound. So sometimes little to no dressing is applied to
wounds. As venous wounds produce a lot of fluid, this can be
And sometimes a dressing is chosen over compression for small
periods of time. If compression is ignored for longer periods,
the wound tends not to heal.
For patients who won't or cannot use compressive stockings, some
manufacturers also make compressive products that slide over the
leg and can be made to provide compression with elastic bands or
straps that can be Velcroed up the leg to provide compression.
In the patient to the right, rheumatoid arthritis prevents her from
being able to put on regular stockings.
This product has allowed her ulcer to heal.
To return to the top of the page,
please click on the maple leaf to
"Nothing is softer or more flexible than water, yet nothing can resist it."
"Water always goes where it wants to go,
and nothing in the end can stand against it."
up and out
of the leg.
This page written by Dr. S A Schumacher
Surrey, British Columbia Canada
All clinical photographs owned and provided
by Dr. S A Schumacher. They may be reproduced
for educational purposes with attribution to:
Dr. S A Schumacher, Surrey, BC Canada
and a link to this website, www.CanadianMAPLE.org.