By 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: Efficacy of MMP-Inhibiting Wound Dressings in the Treatment of Hard-to-Heal Wounds: A Systemic Review

Authors: Dissemond J, Augustin M, Dietlein M, et al.

Journal: J Wound Care. 2020;29(2):102-118

Reviewed by: Preeti Kumrah, class of 2022, Temple University School of Podiatric Medicine

Introduction

Hard-to-heal wounds, such as diabetic foot ulcers, pressure injuries, and venous leg ulcers, comprise a significant portion of health care visits, and these wounds place a physical and economic burden on many patients. These hard-to-heal wounds are defined as wounds with stagnant or delayed stages of healing that fail to resolve within eight weeks. Finding ways to accelerate this healing process is of great importance because it can reduce the physical and economic burden on patients, as well as decreasing costs for health care facilities. Matrix metalloproteinases (MMPs) are endopeptidases, which are involved in many healing processes, including the cell signaling processes, migration processes, angiogenesis, and the degradation of extracellular proteins.

These mechanisms are necessary for the wound healing process by breaking down damaged tissue. In the late stages of healing, when breaking down of tissue is no longer necessary, tissue inhibitors of metalloproteinases down-regulate MMPs. In hard-to-heal wounds, this process is thrown off balance, with delays in the subsequent stages of healing. In an attempt to restore this balance, MMPs have been investigated for their role in wound healing through MMP-inhibiting wound dressings. There have been a number of consequential reviews done using current market wound dressings, such as oxidized regenerated cellulose/collagen and Technology Lipido-Colloid with nano-oligosaccharide factor (TLC-NOSF).

Chronic Wound Breakdown: Most Common Types of Chronic Wounds

Methods

The studies included in this review were conducted with very specific parameters and selection for each criterion to determine the efficacy of wound healing, by comparing MMP-inhibiting dressings, oxidized regenerated cellulose/collagen, and TLC-NOSF dressings. Literature and clinical trials, already available to health care professionals, that compared the wound care dressing materials listed were selected and further scrutinized based on exclusion and inclusion criteria. The parameters were separated and studied extensively by breaking them down into high-quality randomized controlled trials (RCT), medium-quality RCTs, and low-quality RCTs. Significant findings suggest that treatment of the wounds with TLC-NOSF is highly recommended.

Results

Efficacy was determined in terms of wound size reduction and complete healing in a timely manner. Results with TLC-NOSF were found to be of moderate to high quality in comparison with collagen-based dressings. Notably, the International Working Group on the Diabetic Foot recommended the use of TCL-NOSF dressings in infection-free neuroischemic ulcers without severe ischemia. More data from previous RCTs are available for TLC-NOSF in comparison with collagen-based dressing trials, and these trials have more significant data in terms of efficacy of results and methodical approaches of the studies themselves. Results of studies of collagen-based wound dressings showed moderate or low efficacy. The methodical limitations of some of the available studies of collagen-based wound dressings made it difficult to explore the efficacy of collagen on its own.

For example, one study reported ulcer reduction in dimension, but only with the supplementation of growth factors along with the collagen dressing. Of the finalized studies selected to examine the efficacy of collagen dressings, only three of the six trials reported significant wound size reduction. These results were met with hesitation because they could not confirm the results of the other studies.

Comment

Considering that MMP-inhibiting dressings are relatively new on the market, this review examined pre-existing RCTs. Even with a multitude of previous literature available, limitations of these studies demonstrate that not all RCTs performed on MMP-inhibiting wound dressings can be used to derive conclusions appropriate for clinical practice. Examining the studies demonstrates the differences in quality, which consequently affect their strength of evidence when evaluating their efficacy in hard-to-heal wounds.

Conclusion

Results of the studies demonstrated a positive indication that early treatment with MMP-inhibiting dressings resulted in shorter healing times. In clinical practice, the use of TLC-NOSF dressings was indicated for hard-to-heal wounds, such as diabetic foot ulcers and venous leg ulcers. More longer-term studies that monitor the course and progression of healing would be beneficial. As it stands, there is only limited evidence to support the use of collagen-based dressings in the treatment of these wounds.

About The Author

Preeti Kumrah is a second-year podiatric medical student at Temple University School of Podiatric Medicine (TUSPM) in Philadelphia, Pennsylvania. Preeti has always had an interest in medicine and was certain she wanted to become a physician to provide for those who could not help themselves. She has family members who are affected by many health conditions and noticed how it changed their gait and confidence. With the personal exposure, she decided that the podiatric field was best to tackle the challenges she faced, especially coming from a minority background that misunderstood the importance of foot care. In fall 2018, she matriculated to TUSMP. She has attended conferences on diabetic wound care and has a very keen interest in gaining more knowledge in the field. Preeti also has a great interest in dermatology, diabetic limb salvage, vascular support, and podopediatrics. She hopes to utilize her role as a future podiatrist to engage communities of all backgrounds on the importance of foot care and promote better health education. 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.