A 2-year-old African-American female came to clinic for suture removal 8 days after being cut by a metal edge on her forearm. The pertinent physical exam showed a 2 cm scar that was well healed with no surrounding erythema or tenderness. The diagnosis of healing laceration was made and the sutures were removed. The mother asked about ways to minimize the scarring as she herself had several hypertrophic and keloid scars. She had used different vitamin creams with mixed results and wondered if using silicone sheeting may help. The physician was not sure about it but said she would check and call the family. A PUBMED search found several articles that showed efficacy but that the sheets had to be used for many hours a day and for several weeks to months. She discussed this with the mother who wanted to try using them. The pediatrician cautioned the mother to wait until at least 2 weeks after the injury to begin using them. She also cautioned to try to keep the child from pulling off the sheets and possibly ingesting them. She recommended long-sleeved clothing to minimize this risk and to keep the sheets in place. The patient’s clinical course at her next health supervision examination showed a well-healed minimal scar that was hypopigmented. The pediatrician reminded the mother that hypopigmentation was a common problem with wounds but that the coloring would become more uniform usually over 6-12 months.
There are 3 phases of wound healing:
- Inflammation – the damaged vessels produce exudate to fill the wound
- Granulation – epithelization, re-creation of the blood vessels and reinforcing of the injured area
- Remodeling – fibroblast proliferation with deposition of collagen and remodeling of the area. This can last up to 2 years later.
Hypertrophic scars have an increased amount of scar tissue within the original wound boundary, whereas keloids have tissue that extends beyond the borders.
A recent review article graded the overall efficacy various of topical scar therapies. Silicone gel sheeting had “marked benefit” while pressure therapy (use of custom fitted pressure garments) and Imiquimod cream had “some benefit.” Polyurethane dressings and topical Vitamin A had “equivocal results”, and onion extract and topical Vitamin E had “no adequate benefit.” The Cochrane Collaboration Intervention Review in 2007 concluded that “…[T]rials…are of poor quality and highly susceptible to bias. There is weak evidence of a benefit of silicone gel sheeting as a prevention for abnormal scarring in high risk individuals but the poor quality of research means a great deal of uncertainty prevails.”
Silicone gel sheeting was introduced almost 30 years ago. While it’s mechanism of action remains unclear, postulated effects include increasing temperature, pressure, oxygen tension, hydration and the silicone itself. Some of the data is inconsistent but has shown increased or no change in temperature or pressure around the wound. Silicone sheeting is permeable, thus allowing more oxygen to seep into the hydrated skin and thus improve wound healing. Hydration itself is hypothesized to decrease capillary activity. Data supports silicone sheeting working better than silicone gel or oil by themselves which is consistent with studies showing silicone permeates only slightly into the stratum corneum. Overall it appears that occlusion of the scar and subsequent hydration decreases “…capillary activity, thereby reducing fibroblast-induced collagen deposition and scar hypertrophy.” Hyperremia would thereby be reduced resulting in less wound redness and with less resulting collagen deposition, the scars are flatter.
Looking at the whole, silicone sheeting appears effective for prevention and treatment of hypertrophic scar and/or keloid formation. Most treatment requires wearing the sheeting 12-24 hours/day for at least 2-3 months. Clinical trials vary depending on the wound/scar studied, site and especially treatment length. Studies of new scars appear to show efficacy with shorter treatment periods (2-4 months of treatment with various amounts of followup time) but treatment of old scars may show some efficacy too after longer time periods of treatment.
Silicone sheeting is relatively low cost and easy to use. Silicone sheeting should not be used on unhealed or open wounds. The sheeting is reusable and should be washed with soap and water and dried between uses (at least daily) and needs to be replaced when it begins to disintegrate. Side effects are usually minimal and usually related to hygiene of the underlying skin or irritation of the skin from the product itself. Improving hygiene, changing products, and/or gradually increasing the amount of time using the product can reduce the side effects. The sheeting comes in a variety of forms including self-adhesive or non-adhesive. Some non-adhesive products can have tape applied directly to the sheeting and other products require a seperate bandage over the sheeting to secure it. Therefore some products may be difficult to use. It can be difficult to use the products in areas of movement (e.g. elbows, wrists, etc.).
Questions for Further Discussion
1. What are possible treatments for keloid scars?
2. What are indications for scar revisions?
- Disease: Wounds
- Symptom/Presentation: Trauma
- Age: Toddler
To Learn More
To view pediatric review articles on this topic from the past year check PubMed.
Information prescriptions for patients can be found at MedlinePlus for this topic: Wounds
To view current news articles on this topic check Google News.
To view images related to this topic check Google Images.
Zurada JM, Kriegel D, Davis IC. Topical treatments for hypertrophic scars. J Am Acad Dermatol. 2006 Dec;55(6):1024-31.
Berman B, Perez OA, Konda S, Kohut BE, Viera MH, Delgado S, Zell D, Li Q. A review of the biologic effects, clinical efficacy, and safety of silicone elastomer sheeting for hypertrophic and keloid scar treatment and management. Dermatol Surg. 2007 Nov;33(11):1291-302;1302-3.
O’Brien L, Pandit A. Silicon gel sheeting for preventing and treating hypertrophic and keloid scars. Cochrane Database Syst Rev. 2006 Jan 25;(1):CD003826.
ACGME Competencies Highlighted by Case
1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
2. Essential and accurate information about the patients’ is gathered.
3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
4. Patient management plans are developed and carried out.
5. Patients and their families are counseled and educated.
6. Information technology to support patient care decisions and patient education is used.
7. All medical and invasive procedures considered essential for the area of practice are competently performed.
8. Health care services aimed at preventing health problems or maintaining health are provided.
10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.
12. Evidence from scientific studies related to the patients’ health problems is located, appraised and assimilated.
13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.
14. Knowledge of study designs and statistical methods to appraisal clinical studies and other information on diagnostic and therapeutic effectiveness is applied.
15. Information technology to manage information, access on-line medical information and support the healthcare professional’s own education is used.
17. A therapeutic and ethically sound relationship with patients is created and sustained.
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa Children’s Hospital