Temple University School of Podiatric Medicine Journal Review Club
Editor's note: This post is part of the Temple University School of Podiatric Medicine (TUSPM) journal review club blog series. In each blog post, a TUSPM student will review a journal article relevant to wound management and related topics and provide their evaluation of the clinical research therein.

Article Title: Healing Rates in a Multicenter Assessment of a Sterile, Room Temperature, Acellular Dermal Matrix Versus Conventional Care Wound Management and an Active Comparator in the Treatment of Full-Thickness Diabetic Foot Ulcers
Authors: Jodi Walters, DPM; Shawn Cazzell, DPM; Hau Pham, DPM; Dean Vayser, DPM, FACFAS; Alexander Reyzelman, DPM, FACFAS
Journal Name and Issue: Eplasty, Vol. 16, e10, 2016.
Reviewed by: Michael Brown, Class of 2020, Temple University School of Podiatric Medicine

Introduction

As of February 4, 2016, an estimated 29.1 million people in the United States had diabetes. Diabetic neuropathy, which commonly leads to the formation of diabetic foot ulcers (DFUs), is the most common complication of diabetes. Patients with DFUs report having a lower quality of life than diabetic patients without them. Specifically, these patients report engaging in much less physical activity, having fewer social interactions, and feeling less healthy than has been reported by diabetic patients without DFUs.

Diabetic patients with DFUs are more difficult to treat, have higher mortality rates, and are more expensive to treat than diabetic patients without them. Conventional treatment of DFUs includes debridement, offloading of the wound, dressing the wound, and prevention of infection. However, the wounds do not always heal and can lead to amputation and/or death: 40% of patients with DFUs have a 5-year mortality rate. Treatment of a patient with a DFU averages $31,419 over the course of a year, which is roughly twice the cost of treatment of a diabetic patient without one of these wounds.

The authors of this study tested an alternative method of treatment for DFUs: a type of human acellular dermal matrix (ADM), which provides scaffolding for growth of new tissue, called DermACELL® (D-ADM). D-ADM can increase biomechanical strength of tissue at the application site by promoting the body's natural healing process and the regeneration of normal tissue, as opposed to scar tissue. Based on the promising results of preliminary studies, the authors of this study compared the healing rate of DFUs using D-ADM versus conventional methods and an active comparator, GRAFTJACKET® (GJ-ADM).

Materials and Methods

This study was designed to test the safety and efficacy of D-ADM compared with conventional and GJ-ADM treatments in diabetic patients with chronic DFUs. Patients were randomly assigned to one of the three treatment methods: D-ADM, conventional care, or GJ-ADM. Success of treatment was assessed by the healing rate of wounds and reduction in wound size over the course of 16 weeks. The authors hypothesized that DFUs treated with D-ADM would exhibit higher healing rates than DFUs treated conventionally.

Results

After 12 weeks, 132 patients remained in the study. Eighteen patients in the D-ADM group, 13 in the conventional care group, and 5 in the GJ-ADM group withdrew from the study either for non-compliance or adverse events, which were not elaborated on by the authors, by the 12th week. Another patient withdrew from the study at week 13 because of an increase in the size of the ulcer. The baseline ulcer size for each group was similar at the beginning of the study, so wound closure among the groups could be compared with statistical significance. Some D-ADM patients received two applications of D-ADM, whereas others received only one. The wound closure rate of both groups treated with D-ADM was quicker than that of both GJ-ADM and conventional care at different periods in the study. At the 12-week period, 65% of patients treated with one application of D-ADM healed from their DFU. Only 41.1% healed through conventional treatment, and 56.3% healed from one application of GJ-ADM. At the 16-week period, 82.5% of DFUs in patients treated with one application of D-ADM healed as compared with 48.1% for conventional care and 68.8% for one-time application of GJ-ADM.

For DFUs that did not completely heal by the end of the study, the reduction in area of those wounds was greater in patients treated with one application of D-ADM (94.6%), as opposed to patients treated conventionally (71.6%) or with one application of GJ-ADM (88%) at the 12-week period. At the 16-week period, a 96.3% reduction in area of the wound was seen in patients treated with one application of D-ADM, whereas there was an 80.3% decrease in area for conventional care and an 88.4% decrease in area for one application of GJ-ADM. Two applications of D-ADM were not as effective as one application regarding the number of wounds that healed and the percentage of reduction in wound size, and the same was true for two applications of GJ-ADM.

Conclusions

The benefits of using D-ADM are significant. Its ability to reduce the amount of scar tissue and promote the formation of normal tissue in wounds has many benefits because scar tissue results in loss of sensation, inadequate vascularization, reduced range of motion, and increased incidence of injury secondary to poor tissue quality. D-ADM provides a scaffold that promotes the body's natural wound healing process. The presence of a basement membrane, which D-ADM simulates, is critical for epithelial cell attachment and proliferation. Thus, D-ADM elicits the migration of appropriate reparative cells to the site of injury where the formation of scar tissue would normally ensue. This promotes constructive tissue remodeling through increased vascularization, cell differentiation, and cell proliferation. Subsequently, D-ADM gradually resorbs as the body deposits new, healthy tissue. Specifically, neutrophils and macrophages migrate to and enter the scaffold; then, new blood vessels incorporate themselves into the scaffold; nerve structures begin to form; fibroblasts migrate to the wound and deposit collagen; and immature muscle begins to form, all while D-ADM gradually degrades over a period of 6 to 9 months. Thus, tissue very similar to the original tissue is formed, as opposed to scar tissue.

Although the formation of scar tissue versus normal tissue was not a specific parameter of this study, the rate of tissue formation by D-ADM compared with conventional care and GJ-ADM was drastic. The greater rate of healing and the ability to heal an entire wound demonstrate the valuable restorative capacity of D-ADM and why it should be used in the treatment of DFUs and possibly all types of open wounds caused by unintended injury or surgery.

About the Authors:
Michael Brown is a second-year podiatric medical student at Temple University School of Podiatric Medicine (TUSPM). He graduated from Clemson University in 2016 with a Bachelor of Science in Biological Sciences.

Dr. James McGuire is the director of the Leonard S. Abrams Center for Advanced Wound Healing and an associate professor of the Department of Podiatric Medicine and Orthopedics at the Temple University School of Podiatric Medicine in Philadelphia.