Prospective Randomized Comparison of Scar Appearances between Cograft of Acellular Dermal Matrix with Autologous Split-Thickness Skin and Autologous Split-Thickness Skin Graft Alone for Full-Thickness Skin Defects of the Extremities.

Abstract

Sir: We read with interest the recent article by Yi and Kim (Plast Reconstr Surg. 2015;135:609e–616e). The authors compared the effect of simultaneous application of acellular dermal matrix with autologous split-thickness skin graft and that of split-thickness skin graft alone on traumatic full-thickness skin defects on the extremities, and concluded that the cograft of acellular dermal matrix with split-thickness skin graft produced better outcomes than split-thickness skin graft alone in terms of scar appearance, without increasing complications. The combination of acellular dermal matrix with epidermal coverage, usually an autologous split- thickness skin graft, has increasingly replaced the full-thickness skin graft to reconstruct full-thickness skin defects. However, the timing of split-thickness skin grafting remains controversial. For a split-thickness skin graft to attach promptly after transplantation, a well-vascularized wound bed is required. The thickness of a skin graft that can easily become vascularized is approximately 0.7 to 1.0 mm. Therefore, most acellular dermal matrices thicker than 1.0 mm are covered by a split-thickness skin graft 3 to 4 weeks later to allow sufficient vascularization and to avoid graft necrosis or loss.1 However, this two-step approach is lengthy, gives no guarantee of success, and is an additional stress factor for the patient. More recent approaches include use of thinner dermal layers, with the aim of transplanting acellular dermal matrix simultaneously with split-thickness skin graft.2 Several of the authors’ procedures might contribute to the success of their single-step technique: (1) the wound bed was completely débrided and prepared with well-vascularized granulation tissue before grafting, (2) negative-pressure therapy was applied throughout to stimulate angiogenesis and prevent complications, and (3) the application of meshed acellular dermal matrix and thin split-thickness skin graft improved the take rate and allowed better blood supply to the cograft. However, we still have great interest in the thickness of the acellular dermal matrix in this article. Does the meshed morphology of acellular dermal matrix compensate for the thickness of it? In addition, the split-thickness skin graft combined with acellular dermal matrix was meshed and expanded, whereas the split-thickness skin graft applied alone was neither meshed nor expanded and was 0.1 mm thicker than the cografted one. The difference interests and confuses us. Beyond this, the pigmentation merits specific attention. Melanocytes and fibroblasts are believed to contribute to the repigmentation process.3 Because acellular dermal matrix does not contain cellular components, it is acceptable in this article that the pigmentation subscore was not improved in the cograft group. In our experience, noncultured autologous cell suspensions, such as ReCell (Avita Medical, Northridge, Calif.), could commendably improve skin color, as it contains viable melanocytes and fibroblasts apart from abundant keratinocytes.4 As these authors move forward, it could be tentatively used to aid the cograft of acellular dermal matrix and split-thickness skin graft or even cografted directly with acellular dermal matrix to heal full- thickness skin defects. We agree with the authors that the one-step graft of acellular dermal matrix and split-thickness skin graft is more than welcome and encourage them and others to investigate this approach so that this very important technique can be more completely understood and taken advantage of. DISCLOSURE The authors have no financial interest to declare in relation to the content of this communication. Panxi Yu, M.D.Zuoliang Qi, M.D., Ph.D.Plastic Surgery HospitalChinese Academy of Medical Sciences and Peking UnionMedical CollegeBeijing, People’s Republic of China