MIAMI – Pinch grafting can accelerate the healing of chronic, treatment-resistant wounds such as leg ulcers, while at the same time reducing morbidity to the donor skin site. A new epidermal harvesting device also is showing promise, as is a new tool that minces autologous skin grafts prior to application to promote wound healing.
These and other advances in wound healing were presented at the Orlando Dermatology Aesthetic and Clinical Conference. The pinch grafts and minced grafts each rely on the newly added skin to stimulate cytokines. Interestingly, there is evidence that grafts taken from hair-bearing donor sites could be superior for stimulating cytokines and accelerating wound healing, said Robert Kirsner, MD, PhD, of the University of Miami Health System.
Islands of regrowth
Physicians perform pinch grafting by taking small punches of skin from a donor site on the thigh, abdomen, or elsewhere, and then transferring the grafts to serve as islands of regrowth in a wound. Pinch grafting can be faster and less expensive than techniques typically performed in an operating room, such as meshed auto-grafting. In contrast, pinch grafting can be accomplished in an office setting “and patients can do quite well.” Dr. Kirsner said. In terms of outcomes, “our data is typical,” he added. “About 50% of refractory ulcers heal, 25% improve, and a percentage recur.”
Spreadable skin grafts
Another autologous grafting technique that can be performed at the bedside uses the Xpansion Micro-Autografting Kit, which minces autologous, split thickness skin grafts. “Then you apply them like peanut butter to bread,” Dr. Kirsner said.
The micro-autografts can help heal both acute and chronic wounds, including full thickness wounds from trauma, some burn wounds, diabetic foot ulcers, and venous ulcers, according to the manufacturer’s website.
Epidermal harvesting (without anesthesia)
Epidermal grafting can make sense because the epidermis regenerates. “You can lift off just the epidermis with heat or suction, “ Dr. Kirsner said. For the first time, he added, a new tool allows epidermal grafting without the need for anesthesia (Cellutome Epidermal Harvesting System). The device raises little microdomes of epidermis down to the basal layer, including basal keratinocytes and melanocytes, and a dermatologist can use a sterile dressing to transfer them to the wound. Confocal microscopy shows the dermoepidermal junction healing as early as within 2 days.
The epidermal harvesting was initially developed for pigment problems, such as piebaldism. (). “We quickly realized it might have applicability for nonhealing wounds,” Dr. Kirsner said.
Deeper wound healing
A novel strategy for triggering deeper wound healing evolved from fractional laser technology, which remove columns of skin to generate healing. Instead, Rox Anderson, MD, of Massachusetts General Hospital, Boston, “envisioned pulling up microcolumns of full thickness epidermis, all the way to the fat, placing them into a wound, and the wound would heal with very little donor site morbidity,” Dr. Kirsner said.
This tool is coming out in spring of this year, he noted. It will resemble a fractional laser, “but now you have the skin available to place in another wound.” Prior animal studies revealed a healing benefit with very little scarring, he added.
Is hairier better?
Does the donor site matter? Dr. Kirsner asked. Although dermatologists typically graft skin from an abdomen or thigh, a hair-bearing site may be a better option because of the presence of pluripotent stem cells, according to a case report (). J.D. Fox of the University of Miami, Dr. Kirsner, and their colleagues treated a large, chronic venous leg ulcer, almost 60 cm2, with punch grafts from a variety of donor sites.
“The side that got scalp punch grafts healed better, suggesting with skin taken from richly hairy area, you’ll get better results,” Dr. Kirsner said.
Another study supports this strategy (). These researchers reported greater wound size reduction using grafts containing hair follicles versus nonhairy areas, again suggesting follicular stem cells play a role in better wound healing, Dr. Kirsner said. “This may be a better source of donor skin in the future.”
Dr. Kirsner is a consultant for Cardinal Health, Mölnlycke, Amniox, Organogenesis, Kerecis, Keretec, and KCI, an Acelity company.