This advanced inflammatory change is sometimes called lipodermatosclerosis.
The lower leg may gradually develop a narrower appearance above the ankle while the calf remains relatively full. This has traditionally been described as an inverted champagne-bottle shape.
Such changes suggest longstanding venous disease and deserve medical evaluation.
A 2023 review published in American Journal of Clinical Dermatology explains that stasis dermatitis is a chronic inflammatory condition associated with venous hypertension and that persistent disease can lead to significant skin changes and venous ulceration.
PubMed Central (PMC)+1
2. Why Does the Skin Turn Rusty Brown and Scaly?
To understand why stasis dermatitis develops, it helps to understand how blood normally circulates through the legs.
The heart pumps oxygenated blood through arteries toward the body's tissues. After delivering oxygen and nutrients, blood returns toward the heart through veins.
Unlike arteries, veins must move blood against gravity when it travels upward from the legs.
They rely on several mechanisms to accomplish this, including one-way valves inside the veins and the pumping action of the calf muscles.
When these systems function properly, blood moves upward efficiently, and the valves prevent it from flowing backward.
However, when the valves become damaged or weakened, blood can move backward and accumulate in the lower extremities.
This condition is known as chronic venous insufficiency.
The Role of Damaged Vein Valves
Veins contain small valves that open to allow blood to move toward the heart and close to prevent backward flow.
Over time, these valves may become less effective.
This can happen because of:
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Age-related changes.
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Previous deep vein thrombosis.
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Longstanding varicose veins.
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Previous damage to the veins.
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Conditions that interfere with normal venous circulation.
When the valves do not close properly, blood can pool in the lower legs.
The resulting pressure is called venous hypertension.
Rather than returning efficiently to the heart, blood remains in the lower extremities for longer periods, particularly when someone is standing or sitting with the legs down.
How Fluid Leaks Into the Surrounding Tissue
As pressure increases inside the small blood vessels, fluid can move into surrounding tissues.
This produces edema, the medical term for swelling caused by excess fluid accumulation.
The swelling stretches the skin and contributes to inflammation.
Over time, inflammatory processes can weaken the normal protective barrier of the skin, making it dry, itchy, and vulnerable to injury.
This is why stasis dermatitis is not simply a cosmetic pigmentation problem.
The visible changes are part of a broader process involving abnormal circulation, fluid accumulation, and chronic inflammation.
Why the Skin Becomes Brown: The Role of Hemosiderin
The rusty-brown color has a particularly interesting explanation.
When pressure increases inside small blood vessels, some red blood cells may escape into surrounding tissues.
Red blood cells contain hemoglobin, the protein responsible for transporting oxygen.
As these cells break down, iron-containing material can remain in the skin.
The body stores some of this iron in a pigment called hemosiderin.
Hemosiderin deposits can create the characteristic brown or reddish-brown discoloration associated with chronic venous disease.
This explains why the pigmentation may remain visible even when the skin is no longer actively inflamed.
It also explains why ordinary washing, exfoliation, or cosmetic creams cannot simply remove the staining.
The pigment is associated with changes within the tissue itself.
Why the Skin Becomes Scaly and Irritated
The inflammatory process affects the skin's natural protective barrier.
Healthy skin helps retain moisture and protects the body against external irritants, allergens, and microorganisms.
When chronic inflammation disrupts this barrier, moisture escapes more easily, leaving the surface dry and vulnerable.
The result may include:
Swelling can make these problems worse by placing additional stress on already fragile skin.
Repeated scratching then creates a cycle in which itching leads to skin damage, skin damage increases irritation, and irritation produces more itching.
Breaking this cycle is an important part of treatment.
Why the Condition Often Appears Near the Ankles
Gravity is a major reason why the ankles and lower shins are commonly affected.
When a person stands or sits for long periods, pressure within the veins of the lower legs increases.
The lower extremities are also farther from the heart than most other parts of the body, meaning that blood must travel a greater distance against gravity.
The ankle region is therefore particularly vulnerable to the effects of prolonged venous pressure.
This is why early stasis dermatitis frequently appears around the inner ankles before spreading to nearby areas.
3. Who Is Most Likely to Develop Stasis Dermatitis?
Stasis dermatitis can occur in adults of different ages, but it is especially common among older individuals.
Aging affects several components of the circulatory system. Vein walls may become less elastic, valves can become less effective, and other health conditions may contribute to fluid accumulation.
However, age alone does not explain every case.
Several medical and lifestyle factors can increase the likelihood of developing chronic venous insufficiency and its associated skin complications.
Older Adults
People over 60 are more likely to experience chronic venous disease because the veins have been exposed to decades of normal pressure and mechanical stress.
Older adults are also more likely to have conditions such as reduced mobility, cardiovascular disease, or previous blood clots.
These factors can contribute to persistent swelling and skin changes.
People With Varicose Veins
Varicose veins are enlarged, twisted veins that often appear near the surface of the legs.
They develop when blood does not move efficiently through the venous system.
Although some people with varicose veins experience no significant symptoms, others develop heaviness, aching, swelling, and skin changes.
Longstanding venous disease can eventually contribute to stasis dermatitis.
People With a History of Deep Vein Thrombosis
Deep vein thrombosis (DVT) occurs when a blood clot forms in a deep vein, usually in the leg.
Even after the clot has been treated, some people experience lasting damage to the vein valves.
This can lead to a condition called post-thrombotic syndrome, which may cause:
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Persistent leg swelling.
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Pain or heaviness.
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Skin discoloration.
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Varicose veins.
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Chronic venous ulcers.
A previous DVT is therefore an important part of the medical history when evaluating brown discoloration around the ankles.
People With Limited Mobility
The calf muscles help push blood upward through the veins.
Every time a person walks, the calf muscles contract and compress nearby veins, helping blood return toward the heart.
This mechanism is sometimes called the calf-muscle pump.
When someone spends most of the day sitting or remains in bed for extended periods, the calf muscles are activated less frequently.
Reduced movement can therefore contribute to venous pooling and swelling.
For older adults who have difficulty walking, even small amounts of regular movement, when medically appropriate, may help support circulation.
People With Obesity
Excess body weight can increase pressure on the venous system and make it more difficult for blood to return efficiently from the legs.
Obesity is also associated with reduced mobility and several conditions that can contribute to swelling.
This does not mean that body weight is the only cause of venous disease. Rather, it is one of several factors that may influence circulation.
People With Heart Failure
