Experience Using a Synthetic Terpolymer Matrix in Chronic Wounds

Introduction: Polylactic acid polymers have been utilized as dermal matrices in wound healing as they can form porous membranes that are non-immunogenic, bioactive, and biodegradable, helping facilitate repair, collagen deposition, angiogenesis, and cellular signaling. [1] As they degrade, they also decrease the wound bed pH, effectively reducing matrix metalloprotease (MMP) activity, increasing tissue oxygenation, and deterring microbes. [2] We examined the use a novel, synthetic terpolymer matrix (STM*) composed of polylactic acid, trimethylene carbonate, and ε-caprolactone in chronic wounds of varying etiologies.Methods:Seven recalcitrant wounds underwent operative debridement followed by STM* application. A nonadhesive dressing was placed overlying and compression was applied, when appropriate, with planned 1 week follow-up. At follow-up, the overlying nonadhesive layer was left in place to allow for maximal product resorption, but outer dressings were changed. Patient wounds were assessed weekly and subjective pain, wound size, and degree of drainage were recorded.Results:All wounds had been present for an average of 4.2 years (2 – 7 years) and areas ranged from 7.2cm2– 67.2cm2 (average 40cm2). Two atypical wounds complicated by CVI reduced by 40.9% and 19.8% at 2-week follow up, and had 52.5% and 33.6% reduction by week 4. The patient also endorsed less pain and drainage. Both wounds plateaued thereafter, and pain and drainage increased. By week 10, wounds were 50% and 22.3% the initial wound size. A mixed arteriovenous ulcer showed a 22% WAR at week 1 of follow-up, but due to primary dressing dislodgement and loss of non-resorbed STM*, the wound was no longer tracked. A chronically infected post-surgical wound had increased by 15.3% at week 1 of follow-up and bioslough was evident throughout the wound bed. The patient then disclosed he couldn't tolerate the antibiotics prescribed after surgery, so he was planned for readmission, repeat debridement, and eventually underwent STSG. Three wounds were recalcitrant VLUs due to sickle cell disease. During the first 4 weeks of follow up, all wounds had a positive but slow trajectory however, by week 6, only one wound continued to improve. Discussion: The STM* is useful as an initial dermal scaffold and postoperatively, wounds had good matrix incorporation with new granulation. Patients also endorsed less drainage and pain. However, once the product fully resorbed, wounds seemed to stall. Reapplications may therefore be an essential component of STM* efficacy, and it may be best suited for the outpatient setting. Additional assessment with reapplications would be a worthwhile future pursuit.References:1. Chen HL, Chung JWY, Yan VCM, Wong TKS. Polylactic Acid-Based Biomaterials in Wound Healing: A Systematic Review. Adv Skin Wound Care. 2023 Sep 1;36(9):1-8. doi: 10.1097/ASW.0000000000000011. PMID: 37530559. 2. Polymedics Innovations Inc. Supra SDRM: Novel synthetic guided wound closure matrix for difficult to heal wounds. https://polymedics.com/wp-content/ uploads/2022/10/MA-P-One-Page-SDRM-US-2022-10-FIN-low-resolution.pdf. 2023.