Keloid vs Hypertrophic Scar: Differences and Management Approaches

Distinguish between keloid and hypertrophic scars. This guide clarifies their key differences in appearance and growth beyond the wound, explaining why the management approaches for each type may differ.

Understanding Raised Scars: A Quick Overview

When the skin is injured, the body’s natural healing process begins, forming fibrous tissue, primarily made of collagen, to repair the wound. In most cases, this results in a flat, pale scar that gradually becomes less noticeable. However, sometimes the body produces a larger amount of collagen, which can lead to the development of raised, thickened scars.

These elevated scars are a common cosmetic concern and can sometimes cause discomfort, itching, or tenderness. While they may look similar initially, there are two types of raised scars that arise from this abnormal healing response: hypertrophic scars and keloids.

Understanding the fundamental difference between them is important for informed discussion with healthcare professionals. A hypertrophic scar generally remains within the original boundaries of the wound, while a keloid may extend beyond these borders, affecting surrounding skin. This distinction helps healthcare professionals determine suitable management approaches for each condition.

What is a Hypertrophic Scar

A hypertrophic scar is a thick, raised scar that develops as a response to skin injury. It results from abnormal collagen production at the site of the wound. Unlike keloids, a hypertrophic scar usually remains within the boundaries of the original injury and may change in appearance over time.

Key Characteristics

Understanding the features of a hypertrophic scar is important for identification. These scars are typically:

• Raised and Firm: They are elevated above the surrounding skin and may feel firm or rubbery to the touch.

• Confined to the Wound Site: Scar tissue generally does not extend beyond the original edges of the cut, burn, or incision.

• Color: Initially, scars often appear red or pink. Over time, they may flatten and become paler.

• Timeline: Hypertrophic scars often develop within weeks following skin trauma and may change in size over several months.

Common Causes

Hypertrophic scarring may result from increased tension and inflammation during the healing of a dermal injury. Abnormal collagen activity can be influenced by various factors, including:

• Surgical Incisions: Post-operative scars, especially in areas of high skin tension such as the chest, shoulders, and upper back, are commonly associated with hypertrophic scarring.

• Burns: Second- and third-degree burns can lead to hypertrophic scars due to prolonged inflammation during healing.

• Traumatic Injuries: Deep cuts, lacerations, and abrasions may contribute to the development of hypertrophic scars.

• Acne and Piercings: Severe cystic acne or inflammation from body piercings can sometimes result in raised, hypertrophic scars.

• Infection: Wounds that become infected or heal slowly may have an increased risk of hypertrophic scarring.

What is a Keloid Scar

A keloid is a type of raised scar that results from abnormal collagen activity during the healing process. Unlike other scars, keloids may extend beyond the boundaries of the original skin injury.

Most wounds heal with a flat scar, but keloids may continue developing, resulting in a raised area on the skin. They are considered benign (non-cancerous) growths and can sometimes cause discomfort or emotional concern.

Defining Features of Keloids

Keloids have several characteristics that differentiate them from other types of scars:

• Growth Beyond Wound Borders: The scar tissue may extend beyond the initial wound boundaries.

• Appearance: Keloids are typically shiny, smooth-surfaced, and firm or rubbery to the touch. Their color can range from pink or red to darker tones than the surrounding skin.

• Continuous Growth: Keloids may grow slowly over months or years, and spontaneous regression is uncommon.

• Symptoms: Some keloids are accompanied by itching, tenderness, pain, or a burning sensation, particularly during their growth phase.

Genetic and Risk Factors

The tendency to form keloids may be influenced by certain factors:

• Genetic Predisposition: Family history may increase the likelihood of developing keloids.

• Skin Pigmentation: Individuals with darker skin tones may have a higher risk of keloid formation.

• Age: Keloids can occur at any age, though certain age groups may have different risk profiles as determined by healthcare professionals.

• Injury Location: Areas of the body with higher skin tension, such as earlobes, chest, shoulders, and upper back, may be more prone to keloid formation.

• Type of Trauma: Certain types of injuries, including burns, surgical cuts, severe acne, and chickenpox scars, may carry a higher risk of keloid formation in susceptible individuals.

Keloid vs Hypertrophic Scar: The Main Differences

While both keloids and hypertrophic scars are raised, fibrous growths resulting from abnormal healing responses, they have distinct clinical features. Understanding these distinctions may help guide diagnosis and selection of appropriate management options.

Appearance and Boundaries

• Hypertrophic Scar: This type of scar is raised, firm, and typically red or pink. Its most defining feature is that it generally remains within the boundaries of the original injury and does not usually extend to the surrounding healthy skin.

• Keloid Scar: A keloid is also raised but often has a lumpy, irregular, or ridged appearance. Its color can range from pink to dark brown. A keloid may extend beyond the original wound site and affect surrounding skin.

Growth and Progression

• Hypertrophic Scar: These scars typically develop within weeks after a skin injury. They may grow for several months but often stabilize and can partially or fully flatten over time.

• Keloid Scar: Keloids may appear months or even years after the initial trauma. They may grow slowly over months or years, and spontaneous regression is uncommon.

Location on the Body

• Hypertrophic Scar: Can form on any part of the body following a skin injury, particularly over joints where the skin is under tension.

• Keloid Scar: While they can occur anywhere, keloids are more likely to develop in specific areas, including the earlobes (from piercings), chest, shoulders, and upper back.

Symptoms and Discomfort

• Hypertrophic Scar: May cause mild itching or discomfort, but these symptoms are generally less severe and tend to improve as the scar matures.

• Keloid Scar: Keloids may be accompanied by symptoms such as itching, tenderness, or discomfort at the scar site.

Management Approaches for Hypertrophic Scars

Unlike keloids, hypertrophic scars have a higher chance of improving on their own over time. However, treatment may help support healing, improve the scar’s appearance, and alleviate symptoms such as itching or tenderness. Treatment plans are often tailored to the scar's size, location, and severity.

Silicone Sheets and Gels

Silicone gel sheeting is commonly used for managing hypertrophic scars. This non-invasive option is available over the counter and works by hydrating the scar tissue.

• How it works: The silicone creates a protective barrier that locks in moisture. This hydration may influence fibroblast activity and abnormal collagen activity, which may contribute to changes in scar texture over time.

• Application: Sheets or gels are applied directly to clean, dry scar tissue and are typically worn for extended periods each day for several months.

Pressure Therapy

Applying continuous pressure to a healing wound or an existing hypertrophic scar is a recognized method to support scar management, especially for larger scars resulting from burns or trauma.

• How it works: Pressure garments, elastic bandages, or specialized dressings apply mechanical force to the scar. This pressure may influence abnormal collagen activity in the scar tissue.

• Application: Pressure is typically applied over long periods, often for several hours a day for months.

Corticosteroid Injections

For more persistent or symptomatic hypertrophic scars, a doctor may recommend intralesional corticosteroid injections. This is a clinical treatment commonly used by doctors.

• How it works: A steroid, such as triamcinolone, is injected directly into the scar tissue. The anti-inflammatory properties of corticosteroids may influence excess collagen fibers and fibroblast activity, which may contribute to changes in scar appearance.

• Application: A series of injections may be administered every 4 to 6 weeks. Patients may notice improvement in the scar's appearance and a reduction in symptoms such as itching and discomfort over multiple sessions.

Management Approaches for Keloids

Keloids may sometimes be managed with combination therapies depending on their size, location, and previous treatment history. A doctor will recommend a treatment plan tailored to each patient. Treatment aims to reduce the appearance of the scar and may help lower the risk of recurrence.

Cryotherapy

Cryotherapy involves exposing keloid tissue to extreme cold, typically using liquid nitrogen administered by a doctor with a spray gun or a cotton-tipped applicator. The cold may affect keloid tissue and its blood supply, which may influence scar characteristics. Multiple sessions may be required as determined by healthcare professionals.

Cryotherapy may be used for smaller keloids and is sometimes combined with corticosteroid injections under a doctor's guidance.

Surgical Excision

Surgical excision involves removing keloid scar tissue. When used alone, recurrence of keloids after surgical excision may be common.

To help manage recurrence, surgery may be combined with additional therapies. This may involve corticosteroid injections during and after surgery or, in some cases, follow-up radiation therapy, as advised by a medical professional.

Laser Therapy and Radiation

Energy-based treatments can effectively manage keloids by targeting the scar tissue at a cellular level.

Laser Therapy

Different types of lasers may be used to treat keloids. The pulsed-dye laser (PDL) may help reduce redness and discoloration and can contribute to changes in the keloid's texture. Other lasers, such as ablative CO2 lasers, may be used to target superficial layers of scar tissue. Multiple sessions may be required to see changes in the scar..

Radiation Therapy

Radiation therapy may be considered to help reduce the risk of keloid recurrence after surgical removal. It may affect collagen production and scar-forming activity. When used with surgery, it may help reduce the likelihood of recurrence. Radiation therapy is administered in controlled, low doses by a qualified professional.

Prevention Strategies for High-Risk Individuals

While abnormal scarring cannot always be prevented, individuals with known predisposition may discuss proactive approaches with healthcare professionals. Those with personal or family history of keloids may benefit from professional guidance regarding post-injury care strategies.

Practice Meticulous Wound Care

Proper wound care may support optimal healing conditions. Creating an appropriate healing environment may influence the skin's repair process.

• Keep the Wound Moist and Clean: Gently cleanse the area daily with mild soap and water to help prevent infection. Afterwards, apply a thin layer of petroleum jelly or an antibiotic ointment to keep the wound hydrated. This may help prevent a hard scab and support organized healing.

• Protect the Area: Cover the wound with a sterile, non-stick bandage to protect the delicate new skin from bacteria, friction, and further injury. Change the dressing regularly.

• Avoid Tension: Wounds on joints or high-tension areas like the chest and shoulders may be more prone to abnormal scarring. If possible, limit movements that stretch the skin around a healing wound.

Avoid Unnecessary Skin Trauma

For those who are highly susceptible to keloids, a commonly recommended approach is to avoid elective procedures that may injure the skin, particularly in high-risk areas. Before undergoing any procedure, discuss your scarring risk with a healthcare professional.

• Reconsider Elective Procedures: Be cautious with non-essential cosmetic procedures, tattoos, and body piercings, particularly on areas such as the earlobes, chest, and upper back.

• Manage Acne and Folliculitis: Avoid picking, squeezing, or popping pimples or inflamed hair follicles, as this type of inflammation and trauma may trigger keloids. Consider consulting a doctor to help manage these conditions.

Use Proactive Scar Management Techniques

Once a wound has fully closed and is no longer an open sore, certain products and practices may help influence how the scar matures.

• Silicone Sheets and Gels: This is commonly used as a preventative measure. Applying silicone gel or sheets directly to the new scar may help hydrate the tissue and regulate the activity of collagen-producing cells (fibroblasts). Consistent use over several months may be recommended.

• Pressure Dressings: For larger scars, especially after surgery or a burn, pressure therapy may help manage the scar. This involves wearing a custom-fitted elastic garment or dressing that applies steady pressure to the area, which could help flatten the scar and limit its growth.

• Sun Protection: New scars may be sensitive to sun exposure. Ultraviolet (UV) exposure may cause scar discoloration. Protect scars with broad-spectrum sunscreen SPF 30 or higher as recommended by healthcare professionals.

When to Consult a Doctor

Professional medical evaluation is required for proper diagnosis and management planning. While this information is educational, medical decisions must always be made with qualified healthcare professionals.

While many hypertrophic scars and small keloids are primarily a cosmetic issue, seeking a professional diagnosis is important to ensure proper evaluation and to rule out other skin conditions. A doctor or plastic surgeon can accurately identify your scar type and discuss treatment options appropriate for your situation.

You may consider scheduling an appointment with a healthcare provider if you experience any of the following:

• Uncertainty About the Diagnosis: If you cannot confidently distinguish whether you have a keloid or a hypertrophic scar, a professional evaluation is recommended.

• Rapid Growth or Changes: Any scar that grows quickly, continues to expand months after the initial injury, or changes noticeably in color or texture should be examined by a doctor.

• Significant Discomfort: Consult a specialist if the scar causes persistent itching, tenderness, or a burning sensation, as these symptoms may be addressed with professional guidance.

• Functional Limitation: If the scar tissue is located over a joint, such as a knee, elbow, or shoulder, and it may restrict the range of motion.

• Cosmetic Concerns: If the appearance of the scar causes distress, a doctor can discuss potential options to address aesthetic concerns.

• Signs of Infection: Seek immediate medical attention if the area becomes increasingly red, swollen, warm, or begins to drain pus, which may indicate an infection.

Consulting a healthcare professional early can support more informed decisions, particularly for individuals with a personal or family history of forming keloids. A doctor can provide guidance on preventive care for future injuries, piercings, or surgeries.

Conclusion

Understanding the distinction between a keloid and a hypertrophic scar is an important step toward informed scar management. Both are types of raised scars resulting from increased collagen production during wound healing, but their growth patterns and management approaches differ.

Hypertrophic scars remain confined to the boundaries of the original injury and may improve on their own over time. Keloids, on the other hand, can extend into surrounding tissue and are less likely to regress without intervention. The genetic predisposition for keloids, particularly in individuals with darker skin tones, informs how treatment may be approached.

Treatment options for hypertrophic scars can include silicone sheets, pressure therapy, or corticosteroid injections. For keloids, a doctor may discuss options such as cryotherapy, surgical excision with adjunctive measures, or laser treatments, depending on the individual case.

Professional medical evaluation by a doctor or qualified healthcare provider is essential for accurate diagnosis and appropriate management planning. Only qualified medical professionals can properly identify scar types, assess individual risk factors, and recommend suitable management approaches. All medical decisions regarding scar management must be made in consultation with licensed healthcare practitioners who can evaluate individual circumstances and provide personalized medical advice.

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Note: This article is for educational purposes only and does not constitute medical advice. Individual treatment plans should be developed in consultation with qualified healthcare professionals. Treatment outcomes vary from person to person, and no guarantee of results is intended or implied. All professional treatments mentioned should be performed by licensed medical practitioners in Singapore, using HSA-approved products, devices, and techniques, as applicable.