Chronic Wounds: Causes, Types & Treatment Guide

What Are Chronic Wounds and Why Don't They Heal?

Chronic wounds are wounds that have not healed or shown significant improvement within four to six weeks despite appropriate care. They result from underlying conditions that impair the body's natural healing process, including poor circulation, diabetes, persistent pressure, or venous insufficiency.

Under normal circumstances, the human body has a remarkable ability to heal wounds through a complex, well-orchestrated process involving inflammation, tissue formation, and remodeling. This process typically takes two to four weeks for minor wounds. However, when underlying health conditions interfere with this natural healing cascade, wounds can become chronic, persisting for months or even years without proper intervention.

The prevalence of chronic wounds is significant and growing, particularly as populations age and rates of diabetes and cardiovascular disease increase. Studies indicate that approximately 1-2% of the population in developed countries is affected by chronic wounds at any given time, with the prevalence rising to 3-5% in people over 65 years of age. The economic burden is substantial, with chronic wound care accounting for a significant portion of healthcare expenditures in most countries.

Understanding why a wound fails to heal is the first step toward effective treatment. The underlying cause must be identified and addressed; otherwise, even the most advanced wound dressings and treatments will fail to produce lasting results. This is why comprehensive assessment by healthcare professionals experienced in wound care is essential for anyone with a wound that isn't healing as expected.

The healing process requires adequate blood supply to deliver oxygen and nutrients to the wound site, removal of dead tissue, control of bacterial load, and a moist wound environment. When any of these factors is compromised, healing stalls. Additionally, systemic factors such as malnutrition, certain medications, and underlying diseases can further impair the body's ability to repair damaged tissue.

The Wound Healing Process

Normal wound healing occurs in four overlapping phases: hemostasis (blood clotting), inflammation, proliferation (new tissue formation), and remodeling. In chronic wounds, one or more of these phases is disrupted. Most commonly, the wound becomes stuck in the inflammatory phase, leading to persistent inflammation that prevents progression to tissue repair.

The inflammatory response, while essential for clearing bacteria and debris, becomes counterproductive when it persists beyond its normal duration. Elevated levels of inflammatory molecules (cytokines) and enzymes (proteases) break down the growth factors and new tissue that the body is trying to produce, creating a destructive cycle that prevents healing.

What Are the Different Types of Chronic Wounds?

The main types of chronic wounds include venous leg ulcers (caused by poor vein function), arterial ulcers (caused by reduced arterial blood flow), diabetic foot ulcers (related to diabetes complications), pressure ulcers (from prolonged pressure), and traumatic wounds that fail to heal. Each type has distinct characteristics and requires specific treatment approaches.

Chronic wounds are classified based on their underlying cause, as this determines the appropriate treatment strategy. Accurate diagnosis of wound type is essential because treatments that help one type of wound may be harmful or ineffective for another. For example, compression therapy is the cornerstone of venous ulcer treatment but can be dangerous for arterial ulcers where blood flow is already compromised.

Venous Leg Ulcers

Venous leg ulcers are the most common type of chronic leg wound, accounting for approximately 70% of all leg ulcers. They develop when the venous system fails to efficiently return blood from the legs to the heart. This venous insufficiency can result from damaged or weakened valves in the leg veins, previous deep vein thrombosis (blood clots), or reduced calf muscle pump function.

When venous return is impaired, blood pools in the lower legs, causing increased pressure in the small blood vessels. This leads to fluid leakage into surrounding tissues, causing swelling (edema), skin changes, and eventually tissue breakdown. The classic signs of venous disease include leg swelling that worsens throughout the day and improves overnight, visible varicose veins, brownish skin discoloration (hemosiderin staining) around the ankles, and sometimes eczema-like skin changes.

Venous ulcers typically develop around the ankles, particularly on the inner (medial) aspect of the lower leg. They tend to be shallow with irregular edges, often produce significant amounts of wound fluid (exudate), and may be surrounded by characteristic skin changes. While venous ulcers can be painful, the pain is often less severe than with arterial ulcers and may be relieved by elevating the leg.

Arterial Ulcers

Arterial ulcers result from inadequate arterial blood supply to the legs and feet, a condition known as peripheral arterial disease (PAD). The primary cause is atherosclerosis—the buildup of fatty deposits in the arterial walls that narrows and sometimes blocks the blood vessels. Without adequate blood flow, tissues are deprived of the oxygen and nutrients needed for healing and maintenance.

These ulcers typically occur on the toes, feet, heels, or lower legs, often at pressure points or areas of trauma. They tend to have well-defined, "punched out" edges and a pale or grayish wound bed due to poor blood supply. Arterial ulcers are characteristically very painful, with pain often worsening when the leg is elevated and improving when the leg hangs down—the opposite of venous ulcers.

People with arterial ulcers often experience intermittent claudication—pain in the calves, thighs, or buttocks when walking that is relieved by rest. In severe cases, rest pain develops, particularly at night when lying flat. The affected limb may feel cold, and pulses in the foot may be weak or absent. These wounds require urgent vascular assessment, as severe arterial disease can threaten limb viability.

Diabetic Foot Ulcers

Diabetic foot ulcers are a serious complication of diabetes mellitus, affecting approximately 15-25% of people with diabetes during their lifetime. They result from a combination of factors unique to diabetes: peripheral neuropathy (nerve damage causing loss of protective sensation), peripheral arterial disease, and impaired immune function.

Neuropathy is particularly dangerous because it allows injuries to go unnoticed. A person with diabetic neuropathy may not feel a pebble in their shoe, a blister from ill-fitting footwear, or a cut on their foot. These minor injuries, which would normally prompt immediate attention, can progress to serious wounds. Additionally, diabetes impairs the immune response and wound healing at the cellular level, making even minor wounds slow to heal and prone to infection.

Diabetic foot ulcers typically develop on the bottom of the foot (plantar surface) at pressure points, on the toes, or over bony prominences. They may be painless due to neuropathy, which is dangerous because it delays recognition and treatment. Warning signs include any break in the skin of the foot, calluses with discoloration underneath, or areas of unusual warmth or redness. People with diabetes should inspect their feet daily and seek immediate care for any foot wound.

Pressure Ulcers

Pressure ulcers, also known as bedsores or pressure injuries, develop when sustained pressure on the skin and underlying tissues restricts blood flow, causing tissue damage and death. They typically occur over bony prominences—areas where bone is close to the skin surface—such as the heels, sacrum (tailbone area), hips, and shoulder blades.

These wounds are most common in people with limited mobility, including those who are bedridden, use wheelchairs, or have conditions affecting their ability to change position. Other risk factors include malnutrition, incontinence, reduced sensation, and poor circulation. Pressure ulcers can develop rapidly—sometimes within hours—making prevention through regular repositioning and appropriate support surfaces essential.

Pressure ulcers are classified by depth, from Stage 1 (intact skin with non-blanchable redness) through Stage 4 (full-thickness tissue loss exposing bone, muscle, or tendon). Treatment requires relieving pressure on the affected area, which may involve special mattresses, cushions, or positioning devices, along with appropriate wound care and attention to nutrition.

Traumatic Wounds That Won't Heal

Sometimes wounds resulting from injuries or surgery fail to heal properly, particularly when located on the lower legs. The combination of gravity, distance from the heart, and relatively poor blood supply makes the lower leg a challenging location for wound healing. Post-surgical wounds, lacerations, and skin tears in this area may become chronic, especially in older adults or those with underlying health conditions.

Swelling (edema) is a common complication that impairs healing of traumatic wounds on the legs. The increased fluid pressure stretches wound edges apart and compromises the delivery of oxygen and nutrients to healing tissues. For this reason, compression therapy and leg elevation are often important components of treatment for traumatic wounds on the lower extremities.

Atypical Wounds

Some chronic wounds don't fit neatly into the categories above. These atypical wounds may be associated with inflammatory conditions (such as rheumatoid arthritis or inflammatory bowel disease), infections, malignancy, or reactions to medications. They often have unusual appearances or locations and may develop rapidly.

Atypical wounds require specialist evaluation to identify the underlying cause. Skin biopsy may be necessary to rule out malignancy or confirm an inflammatory condition. Treatment depends on the specific cause and may involve systemic medications in addition to wound care.

When Should You See a Doctor for a Wound That Won't Heal?

Seek medical care if your wound hasn't started healing within two weeks, shows signs of infection (increasing redness, swelling, warmth, discharge, or odor), or if you have diabetes, poor circulation, or take immunosuppressive medications. Seek emergency care for fever, rapidly spreading redness, severe pain, or blackened tissue.

Knowing when to seek professional help for a wound is crucial for preventing complications and achieving optimal healing outcomes. While many minor wounds heal on their own with basic first aid, certain situations require medical evaluation and potentially specialized wound care.

You should contact your healthcare provider if you notice any of the following:

• No improvement after two weeks: If your wound isn't showing signs of healing (getting smaller, less drainage, healthy pink tissue forming) within two weeks, professional assessment is warranted
• Increasing pain: Pain that is getting worse rather than better may indicate infection or inadequate blood supply
• Signs of infection: Spreading redness around the wound, increased swelling, warmth, pus or cloudy discharge, bad smell, or red streaks extending from the wound
• Underlying health conditions: If you have diabetes, peripheral vascular disease, are immunocompromised, or take medications that affect healing
• Leg swelling: Persistent swelling in the leg can impair wound healing and may indicate venous disease
• Cold foot or leg: This may indicate arterial disease requiring urgent evaluation

For people with diabetes, any foot wound should be evaluated promptly by a healthcare professional. Diabetic foot infections can progress rapidly and, in severe cases, lead to amputation. Early intervention significantly improves outcomes. Similarly, people with known peripheral arterial disease should seek prompt evaluation for any new wound, as these wounds may require vascular intervention to heal.

How Are Chronic Wounds Diagnosed and Assessed?

Chronic wound assessment includes detailed history taking, physical examination of the wound and surrounding tissues, vascular assessment (including ankle-brachial pressure index), laboratory tests if infection is suspected, and sometimes imaging studies. The goal is to identify the underlying cause and any factors that may be impeding healing.

Proper diagnosis of a chronic wound involves more than just looking at the wound itself. Healthcare providers need to understand the whole picture—what caused the wound, what's preventing it from healing, and what underlying conditions may be contributing. This comprehensive approach guides treatment decisions and helps predict outcomes.

Medical History

Your healthcare provider will ask about:

• How and when the wound started
• Previous wounds and how they healed
• Medical conditions such as diabetes, heart disease, or vascular disease
• Medications, especially steroids, immunosuppressants, or blood thinners
• Smoking and alcohol use
• Nutrition and weight changes
• Pain levels and what makes the pain better or worse
• Previous treatments and their effects

Physical Examination

A thorough examination includes assessment of the wound itself (size, depth, appearance of the wound bed, condition of wound edges, amount and type of drainage) as well as the surrounding skin and the entire affected limb. Signs of venous disease, arterial disease, or infection are noted. The healthcare provider will check pulses in the feet and may measure ankle blood pressures.

Vascular Assessment

Evaluating blood flow to the affected area is crucial, particularly for leg wounds. The ankle-brachial pressure index (ABPI) compares blood pressure in the ankle to blood pressure in the arm, providing a measure of arterial blood flow to the legs. This simple, non-invasive test helps distinguish venous ulcers (which benefit from compression) from arterial ulcers (where compression could be harmful).

A Doppler ultrasound may be used to listen to blood flow in leg vessels and can provide more detailed information about venous and arterial circulation. In some cases, more advanced imaging such as CT angiography or MR angiography may be needed to plan vascular interventions.

Laboratory Tests

Blood tests may include blood sugar levels (to check for diabetes), hemoglobin (to check for anemia), nutritional markers, and inflammatory markers. If infection is suspected, wound swabs may be taken to identify the bacteria present and guide antibiotic selection. Blood cultures may be necessary if systemic infection is suspected.

Specialist Referral

Depending on the type and severity of the wound, you may be referred to specialists including dermatologists (for atypical wounds or skin conditions), vascular surgeons (for arterial disease), diabetes specialists (for diabetic foot ulcers), or specialized wound care nurses. Many healthcare systems have multidisciplinary wound care teams that bring together expertise from multiple specialties.

How Are Chronic Wounds Treated?

Chronic wound treatment involves addressing the underlying cause (e.g., compression for venous ulcers, revascularization for arterial disease, offloading for diabetic ulcers), appropriate wound cleaning and debridement, selecting suitable dressings, managing infection, controlling pain, and optimizing nutrition. Treatment is individualized based on wound type and patient factors.

Effective treatment of chronic wounds requires a comprehensive approach that addresses not just the wound itself but also the underlying causes and contributing factors. Simply applying dressings without correcting the root cause is unlikely to result in lasting healing. Modern wound care follows evidence-based principles while being tailored to each patient's specific needs.

Treating the Underlying Cause

This is the most critical aspect of chronic wound treatment. For venous ulcers, compression therapy is the cornerstone of treatment, improving venous return and reducing edema. For arterial ulcers, revascularization procedures (balloon angioplasty or bypass surgery) may be needed to restore blood flow. Diabetic foot ulcers require strict blood sugar control and pressure offloading. Pressure ulcers need pressure relief through repositioning and appropriate support surfaces.

Wound Bed Preparation

Before a wound can heal, the wound bed must be prepared to support new tissue growth. This involves:

• Debridement: Removal of dead (necrotic) tissue, debris, and biofilm that impede healing. Methods include sharp debridement (using surgical instruments), enzymatic debridement (using special ointments), autolytic debridement (using moist dressings), and mechanical debridement
• Managing bacterial load: While all wounds contain bacteria, excessive bacterial burden or infection must be controlled
• Maintaining moisture balance: Wounds heal best in a moist environment, but excessive moisture can damage surrounding skin
• Managing wound edges: Healthy wound edges that can migrate across the wound bed are essential for healing

Wound Dressings

Modern wound care uses a wide variety of dressings designed for different wound types and healing stages. The choice of dressing depends on the wound's characteristics—how much it drains, whether infection is present, the condition of surrounding skin, and the treatment goals. Dressings may be changed daily or left in place for several days, depending on the type used and the wound's needs.

Common dressing categories include:

• Foam dressings: Absorbent, cushioning, good for moderate to heavy drainage
• Hydrocolloid dressings: Create moist environment, good for light to moderate drainage
• Alginate dressings: Highly absorbent, made from seaweed, good for heavy drainage
• Antimicrobial dressings: Contain silver or other agents to reduce bacterial load
• Hydrogel dressings: Add moisture to dry wounds, promote autolytic debridement

Compression Therapy for Venous Ulcers

For venous leg ulcers, compression therapy is essential and significantly improves healing rates. Compression works by counteracting the high pressure in leg veins, reducing swelling, and improving blood return to the heart. It should only be applied after arterial circulation has been assessed, as compression can be harmful if arterial disease is present.

Compression can be applied using various methods:

• Multilayer compression bandages: Applied by trained healthcare professionals, these provide sustained compression and are commonly used during the healing phase
• Compression stockings: Easier to self-manage, often used after ulcer healing to prevent recurrence
• Adjustable compression wraps: Allow pressure adjustment and can be applied by patients

If compression causes significant pain increase, the bandages should be removed and healthcare providers contacted, as this may indicate inadequate arterial circulation or other problems.

Managing Infection

All chronic wounds contain bacteria, which doesn't necessarily mean they're infected. The key distinction is between colonization (bacteria present but not causing harm) and infection (bacteria causing tissue damage and impeding healing). Local wound infection may be managed with antimicrobial dressings and more frequent dressing changes. Spreading infection or systemic infection (with fever and feeling unwell) requires antibiotic treatment.

Signs that suggest wound infection include:

• Increasing pain
• Spreading redness beyond wound edges
• Increased swelling and warmth
• Purulent (pus-like) discharge
• Foul odor
• Wound breakdown or enlargement
• Fever or feeling systemically unwell

Pain Management

Chronic wounds can be painful, affecting quality of life and making dressing changes difficult. Pain should be assessed regularly and managed appropriately. Options include:

• Over-the-counter pain relievers such as paracetamol (acetaminophen)
• Prescription pain medications when needed
• Topical anesthetic gels or creams for dressing changes
• Selecting dressings that minimize trauma during removal
• Addressing underlying causes of pain (e.g., compression for venous pain)

Note that NSAIDs (non-steroidal anti-inflammatory drugs like ibuprofen) should be used with caution in older adults due to increased risk of side effects. Consult your healthcare provider before using these medications.

Surgical and Advanced Treatments

When conservative treatment is insufficient, surgical options may be considered:

• Vascular surgery: To improve blood flow in arterial disease or correct varicose veins in venous disease
• Skin grafting: To cover large wounds once the wound bed is healthy
• Negative pressure wound therapy (wound vacuum): Uses controlled suction to remove drainage and promote healing
• Hyperbaric oxygen therapy: May benefit certain wound types, particularly diabetic foot ulcers

What Can You Do Yourself to Help Chronic Wounds Heal?

You can support wound healing by following your healthcare provider's instructions carefully, stopping smoking, eating a nutritious diet high in protein, maintaining good blood sugar control if diabetic, staying physically active, keeping the wound clean and protected, elevating swollen legs when resting, and attending all follow-up appointments.

While professional wound care is essential for chronic wounds, there is much you can do to support healing and prevent complications. Your active participation in your care significantly impacts outcomes.

Stop Smoking

Smoking is one of the most significant modifiable factors affecting wound healing. Nicotine causes blood vessels to constrict, reducing blood flow to healing tissues. Carbon monoxide in cigarette smoke reduces the oxygen-carrying capacity of blood. Additionally, smoking impairs immune function and collagen production. If you smoke, quitting is one of the most important things you can do for wound healing—and your overall health. Healthcare providers can offer support and resources for smoking cessation.

Optimize Nutrition

Wound healing requires adequate nutrition, particularly protein, which provides the building blocks for new tissue. Vitamins (especially C and A) and minerals (zinc, iron) also play important roles. Aim for a balanced diet with adequate protein sources (meat, fish, eggs, dairy, legumes), plenty of fruits and vegetables, and adequate fluids. If you have difficulty eating enough or have specific dietary needs, a dietitian can provide personalized guidance.

Both obesity and being underweight can impair wound healing. If weight is a concern, work with your healthcare team to achieve a healthier weight gradually.

Blood Sugar Control

For people with diabetes, maintaining good blood sugar control is critical for wound healing. High blood sugar impairs immune function, damages blood vessels, and interferes with the cellular processes of wound healing. Work closely with your diabetes care team to optimize your blood sugar management.

Physical Activity

Staying active, within the limits recommended by your healthcare provider, improves circulation and overall health. For leg wounds, regular ankle exercises and calf muscle contractions help pump blood back toward the heart. Avoid prolonged standing or sitting, which can worsen leg swelling. If mobility is limited, work with a physiotherapist to develop an appropriate exercise program.

Leg Elevation

For venous leg ulcers and other conditions causing leg swelling, elevating the legs when resting helps reduce edema and improve healing. Elevate legs above heart level when possible—lying on a bed or sofa with legs supported on pillows is effective. Avoid sitting with legs hanging down for prolonged periods.

Foot Care for Diabetes

If you have diabetes, daily foot inspection is essential. Check all surfaces of your feet, using a mirror for the soles if needed. Look for cuts, blisters, redness, or any changes. Wash feet daily in lukewarm water (test temperature with elbow, not toes), dry carefully between toes, and apply moisturizer (but not between toes). Wear well-fitting shoes and never go barefoot. Seek prompt attention for any foot injury or abnormality.

Follow Your Treatment Plan

Adhere to the treatment plan developed by your wound care team. This includes:

• Keeping scheduled appointments for wound assessment and dressing changes
• Taking prescribed medications as directed
• Wearing compression bandages or stockings as instructed
• Using pressure-relieving devices as recommended
• Reporting any changes or concerns promptly

What Is It Like Living with a Chronic Wound?

Living with a chronic wound can be challenging, affecting physical comfort, daily activities, and emotional well-being. Pain, restricted mobility, frequent healthcare visits, and concerns about the wound can impact quality of life. Support from healthcare providers, family, and patient support groups can help people cope with these challenges.

Chronic wounds affect more than just physical health—they can significantly impact emotional well-being and quality of life. Pain, changes in mobility, the need for frequent dressing changes, and concerns about odor or appearance can be stressful. Some people experience social isolation, depression, or anxiety related to their wound.

It's important to communicate openly with your healthcare team about how the wound is affecting your life. Pain should be addressed—you shouldn't simply accept it as inevitable. If you're experiencing low mood or anxiety, mention this to your healthcare provider, as support is available.

Maintaining social connections and activities you enjoy, as much as possible, supports emotional well-being. Patient support groups, either in-person or online, can provide valuable peer support and practical tips from others who understand the experience of living with a chronic wound.

With appropriate treatment and support, most chronic wounds do eventually heal. Staying engaged with your healthcare team, following your treatment plan, and maintaining hope are all important parts of the healing journey.