Foot ulceration associated with diabetes and critical limb-threatening ischemia (CLTI) represents a complex clinical challenge and if not managed adequately may result in a major limb amputation. As the management of the diabetic foot wound is complex, tissue engineering research into bio-engineered scaffolds and skin substitutes has become a growing area of interest as a strategy to accelerate wound healing and avert amputation. Advanced wound therapies like PriMatrix (Integra LifeSciences, Princeton, US) have become an important strategy in the treatment of difficult to heal chronic foot ulcers. This bovine fetal dermis scaffold traps and binds the patients' own cells to rebuild the dermis layer of the skin to aid in healing. Randomised clinical trials and studies have shown that wounds treated with Primatrix had a faster healing rate than those wounds managed with conventional dressings (1). Most studies to date examined chronic wounds and the exclusion criteria consisted of exposed bone or tendons, active infection or gangrene, osteomyelitis and uncontrolled blood sugar levels. The aim of this study was to evaluate the outcomes of the use of PriMatrix in the closure of wounds for severe diabetic foot infections and CLTI patients with significant tissue loss.

Between February 2020 to December 2021, consecutive inpatients admitted acutely at a single tertiary centre with Society for Vascular Surgery (SVS) Wound, Ischemia, and foot Infection (WIfI) scores of 3 or 4 (2), that had a non-healing foot wound after primary debridement and were deemed suitable for PriMatrix application were included in the study. Participants were prospectively followed up at regular intervals at a multidisciplinary high-risk diabetic foot clinic. The primary endpoint was time to wound closure. The secondary endpoint was number of applications of PriMatrix, re-admission rate and amputation free survival.

There were twenty-two patients included in the study with a median age of 68 (51 - 87) years and sixteen were males. There were eight participants that had a WIfI score of three and fourteen had a WIfI score of four. There were twenty (90%) patients that had diabetes and seven (32%) had end stage renal failure (ESRF) requiring dialysis. Of the total cohort, fifteen patients required revascularisation procedures (8 open, 7 endovascular). Thirteen patients achieved complete wound healing with a median time to wound healing of 148 (29-397) days. Five patients achieved partial to near wound healing with a median time of 85 (66-149) days. Two patients resulted in major limb amputation and two died prior to complete wound healing. The average length of admission was 27 (21-87) days, and none of the patients were re-admitted to the hospital within 90 days of discharge.

This study indicates there may be a role for Primatrix use in the acute setting of high-risk foot infection to improve the efficacy of wound healing associated with diabetes and CLTI and potentially reduce wound related re-admissions. A successful treatment regime incorporating revascularisation when indicated and wound management with PriMatrix could potentially lower amputation rates in the context of advanced WIfI scores.

1. Lantis JC, Snyder R, Reyzelman AM, Van Gils CC, Sigal F, Vayser D, et al. Fetal bovine acellular dermal matrix for the closure of diabetic foot ulcers: a prospective randomised controlled trial. Journal of Wound Care. 2021;30(Sup7):S18-S27. 2. Mills JL, Sr., Conte MS, Armstrong DG, Pomposelli FB, Schanzer A, Sidawy AN, et al. The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System: Risk stratification based on Wound, Ischemia, and foot Infection (WIfI). Journal of Vascular Surgery. 2014;59(1):220-34.e2.