Scar management after burns
Key Points
- Up to 70% of burn survivors develop hypertrophic scars; prevention should be a priority from wound closure onward [1]
- Wounds not healed by 21 days carry substantial hypertrophic scar risk (40%+ at 22-25 days); consider surgical intervention before this threshold when feasible [7]
- Start silicone gel sheeting early after wound closure; it improves scar elasticity with a favorable side-effect profile [9][10]
- Combination therapy (pressure plus silicone) outperforms single-modality treatment for scar prevention [4]
- Use objective scar measurement tools to track response to therapy and guide treatment adjustments [11]
- Ensure patient education materials are written at an accessible reading level to support compliance with scar management programs [15]
Overview
Hypertrophic scarring affects up to 70% of burn survivors [1] and remains the leading driver of long-term morbidity after burn injury, decreasing quality of life and delaying reintegration into society. Scar biology begins at the wound bed and evolves over months to years. Prevention starts with targeted wound care to optimize healing potential and minimize time to wound closure, followed by combination scar modulation therapies.
Pathophysiology
Jeschke et al. [2] reviewed scar biology in a comprehensive Nature Reviews Disease Primer. Wound healing occurs as an intricate response aiming to restore skin integrity, but in hundreds of millions of patients worldwide it results in abnormal scarring. Prolonged inflammation and excessive extracellular matrix deposition, particularly collagen types I and III, are hallmarks of hypertrophic scar formation.
Zhu, Ding, and Tredget [3] focused on the molecular basis, identifying key signaling pathways including TGF-beta/Smad, mechanotransduction, and the role of dermal fibroblasts and inflammatory cells. Abnormal wound healing with more extracellular matrix deposition than degradation drives scar formation.
Gauglitz et al. [4] reviewed pathomechanisms and treatment strategies, noting that multiple studies have led to an abundance of treatment options but no single universally effective therapy. Combination therapy generally outperforms single-modality treatment. Arno et al. [5] reviewed molecular medicine-based strategies including fat grafting, stem cell therapy, and small molecule inhibitors targeting fibrotic pathways. Tredget, Levi, and Donelan [6] discussed the relationship between marrow-derived cells and both hypertrophic scarring and heterotopic ossification, suggesting shared pathophysiologic mechanisms.
Healing time and scar risk
Cubison, Pape, and Parkhouse [7] studied 337 children with scalds monitored for up to 5 years. Hypertrophic scar rates were 0% for wounds healed under 10 days, 8% at 10-14 days, 20% at 15-21 days, 40% at 22-25 days, 68% at 26-30 days, and 92% for wounds taking over 30 days to heal. This landmark study established the 21-day threshold as a clinical decision point.
Pressure garment therapy
Engrav et al. [8] reported a 12-year within-wound randomized study of custom pressure garments, the most rigorous trial design applied to this intervention. Despite pressure garment therapy being standard of care worldwide, this study found modest objective differences, highlighting the gap between clinical practice and rigorous evidence.
Silicone therapy
Ahn, Monafo, and Mustoe reported on topical silicone gel in two publications [9][10]. In their controlled clinical trial [10], silicone gel sheeting applied to 14 hypertrophic scars in 10 adults for 8 weeks showed significant improvement in elasticity measured by elastometer compared with untreated control scars. The mechanism of action is thought to involve hydration and occlusion rather than pressure or temperature effects. Bartell, Monafo, and Mustoe [11] developed the elastometer for noninvasive quantification of elastic properties of scar. Nakamura et al. [12] described Silipos neck wraps combining silicone contact with conforming pressure while allowing functional neck movement.
Other modalities
Engrav, Garner, and Tredget [13] reviewed hypertrophic scar, wound contraction, and hyper-hypopigmentation as interrelated phenomena. Won et al. [14] conducted a systematic review of onion extract efficacy, finding mixed results with some studies showing modest benefit for scar height and symptoms but no consistent superiority over silicone-based products. Manasyan et al. [15] found that most scar treatment patient education materials exceeded recommended reading levels, potentially limiting patient comprehension.
Controversies and Evidence Gaps
Optimal pressure garment dosing remains unresolved. While 23-25 mmHg is the commonly cited target, the Engrav et al. [8] study raised questions about the magnitude of benefit. Compliance is a major confounder. The relative roles of intralesional corticosteroids versus laser therapy lack head-to-head randomized comparison. Timing of scar intervention is debated: molecular evidence [3][5] suggests earlier intervention during the proliferative phase may be more effective, but clinical trials confirming optimal timing are lacking. The Cubison et al. [7] 21-day threshold data come from pediatric scalds; generalizability to adults and other etiologies requires further validation.
References
[1] Finnerty CC et al. (2016). Hypertrophic scarring: the greatest unmet challenge after burn injury. PMID: 27707499 [2] Jeschke MG et al. (2023). Scars. PMID: 37973792 [3] Zhu Z et al. (2016). The molecular basis of hypertrophic scars. PMID: 27574672 [4] Gauglitz GG et al. (2011). Hypertrophic scarring and keloids: pathomechanisms and current and emerging treatment strategies. PMID: 20927486 [5] Arno AI et al. (2014). New molecular medicine-based scar management strategies. PMID: 24438742 [6] Tredget EE et al. (2014). Biology and principles of scar management and burn reconstruction. PMID: 25085089 [7] Cubison TCS et al. (2006). Evidence for the link between healing time and the development of hypertrophic scars (HTS) in paediatric burns due to scald injury. PMID: 16901651 [8] Engrav LH et al. (2010). 12-Year within-wound study of the effectiveness of custom pressure garment therapy. PMID: 20537469 [9] Ahn ST et al. (1991). Topical silicone gel for the prevention and treatment of hypertrophic scar. PMID: 2009067 [10] Ahn ST et al. (1989). Topical silicone gel: a new treatment for hypertrophic scars. PMID: 2529659 [11] Bartell TH et al. (1988). A new instrument for serial measurements of elasticity in hypertrophic scar. PMID: 3220875 [12] Nakamura DY et al. (1998). Silipos neck wraps. PMID: 9556324 [13] Engrav LH et al. (2007). Hypertrophic scar, wound contraction and hyper-hypopigmentation. PMID: 17665520 [14] Won P et al. (2025). The Efficacy of Onion Extract on the Prevention or Treatment of Scars: A Systematic Review. PMID: 38894613 [15] Manasyan A et al. (2024). Navigating Scar Care: An Evaluation of Scar Treatment Patient Education Materials. PMID: 38623992