Diagnostic Procedures

Widened scars can be easily differentiated from hypertrophic and keloid scars based on findings from a physical examination. Widened scars are flat and sometimes even depressed. Clinically, keloids can be differentiated from hypertrophic scars because they grow outside the confines of the original scar.

Under light microscopy, hypertrophic scars and keloids are indistinguishable. However, Ehrlich demonstrated a number of differences when viewed under an electron microscope and when evaluated immunochemically.^[41]Keloids contain thick collagen fibers with increased epidermal hyaluronic content, whereas hypertrophic scars exhibit nodular structures with fine collagen fibers and increased levels of alpha smooth muscle actin.^{[42, 43]}

Histologic Findings

The collagen in both keloids and hypertrophic scars is organized in discrete nodules, frequently obliterating the rete pegs in the papillary dermis of the lesions. While collagen in normal dermis is arranged in discrete fascicles separated by considerable interstitial space, collagen nodules in keloids and in hypertrophic scars appear avascular and unidirectional and are aligned in a highly stressed configuration.^{[44, 45]}

Treatment & Management

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Media Gallery

This patient's neck wound developed a hypertrophic scar. It was revised with a fusiform excision and an intraoperative triamcinolone (Kenalog) injection. Postoperatively, the patient used silicone gel daily for 6 months and obtained a very satisfactory result.
This patient underwent revision of her widened scar with a Millard 2-flap technique. The fusiform was incised around the deepithelialized scar. The wound edges were approximated over the deepithelialized scar. Postoperatively, she wore a compression garment and applied silicone gel for 6 months.
This patient was unsatisfied with her hypertrophic wound across the volar aspect of her forearm. She underwent a W-plasty scar revision because the wound was not under significant tension.

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Author

Bradon J Wilhelmi, MD Leonard J Weiner, MD, Professor and Chief of Plastic Surgery, Plastic Surgery Residency Program Director, Hiram J Polk, Jr, MD, Department of Surgery, University of Louisville School of Medicine

Bradon J Wilhelmi, MD is a member of the following medical societies: Alpha Omega Alpha, American Association for Hand Surgery, American Association of Clinical Anatomists, American Burn Association, American College of Surgeons, American Society for Aesthetic Plastic Surgery, American Society for Reconstructive Microsurgery, American Society for Surgery of the Hand, American Society of Plastic Surgeons, Association for Surgical Education, Plastic Surgery Research Council, Wound Healing Society

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Wayne Karl Stadelmann, MD Stadelmann Plastic Surgery, PC

Wayne Karl Stadelmann, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Surgeons, American Society of Plastic Surgeons, New Hampshire Medical Society, Northeastern Society of Plastic Surgeons, Phi Beta Kappa

Disclosure: Nothing to disclose.

Chief Editor

Joseph A Molnar, MD, PhD, FACS Medical Director, Wound Care Center, Associate Director of Burn Unit, Professor, Department of Plastic and Reconstructive Surgery and Regenerative Medicine, Wake Forest University School of Medicine

Joseph A Molnar, MD, PhD, FACS is a member of the following medical societies: American Medical Association, American Society for Parenteral and Enteral Nutrition, American Society of Plastic Surgeons, North Carolina Medical Society, Undersea and Hyperbaric Medical Society, Peripheral Nerve Society, Wound Healing Society, American Burn Association, American College of Surgeons

Disclosure: Received grant/research funds from Clinical Cell Culture for co-investigator; Received honoraria from Integra Life Sciences for speaking and teaching; Received honoraria from Healogics for board membership; Received honoraria from Anika Therapeutics for consulting; Received honoraria from Food Matters for consulting.

Additional Contributors

Christian E Paletta, MD, FACS Clinical Professor of Surgery and Instructor of Surgery, Department of Surgery, Dartmouth-Hitchcock Medical Center, Geisel School of Medicine at Dartmouth; Clinical Professor of Surgery and Instructor in Surgery, Rwanda Human Resources for Health, Rwanda Ministry of Health and Clinton Health Access Initiative

Christian E Paletta, MD, FACS is a member of the following medical societies: American Society of Plastic Surgeons, Plastic Surgery Research Council, American Council of Academic Plastic Surgeons, American College of Surgeons, American Medical Association

Disclosure: Nothing to disclose.