SCOTTSDALE, ARIZ. When a complex lower-extremity wound is unresponsive to conventional treatments and amputation looms as the only option, an acellular regenerative tissue matrix can be effective, Brock A. Liden, D.P.M., said at the annual meeting of the Wound Healing Society.
"Bioengineered skin grafts have become a promising alternative for the treatment of chronic, nonhealing, full-thickness lower-extremity wounds," said Dr. Liden, whose retrospective study evaluated the Graftjacket (Wright Medical Technology Inc.) human acellular dermal matrix.
"The matrix maintains a moist wound environment during the incorporation phase of wound healing and provides a barrier to the outside to reduce the chance of infection, and granulation tissue forms within 57 days, reducing the depth of wounds," explained Dr. Liden, a podiatrist in Circleville, Ohio.
The double-layered membrane, which prompts revascularization of the reticular layer and wound closure, can be applied over tendon and bone.
The regenerative tissue matrix was applied to 23 wounds on 13 patients under a standard protocol, and wounds were assessed using the University of Texas diabetic wound classifications. Dr. Liden said that 12 of the wounds were classified as III-D (infected to the bone) and had poor blood supply.
The cohort's average age was 62 years, with women outnumbering men 3:2. Nearly all patients had cardiac disease, while 78% were diabetic, 69% had infection on initial presentation, 65% had osteomyelitis initially, and 91% had peripheral vascular disease. The average age of treated wounds was 17 weeks.
"This was not front-line defense," explained Dr. Liden. "Everything else had failed for these patients." The defense held, with all but two of the patients achieving complete healing.
One exception was a woman who had stepped on a nail, developed an abscess, and required amputation.
The other was a noncompliant man who was successfully treated on a second attempt.
"The average time to graft incorporation, which is what I consider to be the most important part of the treatment, was about 1 week, and we averaged about 12 weeks to complete healing. The quickest we healed was 3 weeks and the slowest was 30 weeks," Dr. Liden explained. "This acellular tissue matrix is safe and efficacious for complex lower-extremity wounds and is universally applicable."
Graftjacket has several advantages over conventional wound coverings. "It has extremely high tensile strength, retains its vascular channels, and incorporates and converts in the host tissue. The collagen in this product is utilized rather than replaced. Also, its acellular structure eliminates worry about inflammation and rejection," he said, adding that growth factors FGF2 and VEGF are present in the product upon application.
When the graft is used on a full-thickness wound, he explained, it's important to remove as much necrotic tissue as possible and try to get down to the bleeding wound bed.
"Make sure the graft doesn't 'tent,' which occurs when you don't make maximum contact with the wound. And watch for bleeding, which can lift the graft away from the wound bed," Dr. Liden said. He added that the matrix has to be anchored down like a skin graft to eliminate motion.
"The more motion that occurs, the higher the chance of failure," he said, advising against the use of Steri-Strips. "You can lay this over necrotic tissue, bone, or tendonall of which I've done without problems."
Dr. Liden acknowledged receiving a retainer, contribution to research funds, and contribution to travel funds from Wright Medical.