Ovine Forestomach Matrix in the Surgical Management of Complex Volumetric Soft Tissue Defects: A Retrospective Pilot Case Series.

Background: Volumetric soft tissue loss is an urgent surgical issue and can frequently lead to suboptimal outcomes for patients due to significant soft tissue loss, compromised vital structures, and contamination. Ovine forestomach matrix (OFM) has demonstrated clinical success in the surgical management of soft tissue defects, especially in contaminated fields, and provides an effective option for immediate coverage of exposed vital structures before definitive closure. Methods: This retrospective pilot case series (n = 13 defects) evaluated the clinical effectiveness of OFM (graft and/or particulate formats) in the surgical management of contaminated volumetric soft tissue defects. Patients presented with significant soft tissue loss, often with exposed viscera, tendon, bone, or muscle, and were treated with OFM as part of their inpatient surgical management. All patients had at least 1 significant comorbidity with the potential to complicate their healing trajectory. The primary study endpoint was time to 100% granulation tissue coverage (days), and the secondary endpoint was any device-related postoperative complications. Results: A total of 13 volumetric soft tissue defects were evaluated in 10 patients who underwent surgical reconstruction. Mean defect age was 3.5 ± 5.6 weeks, and mean area was 217.3 ± 77.9 cm2. Most defects had exposed structures (85%), and all defects were Centers for Disease Control and Prevention grade 2 or higher. Mean time to 100% granulation tissue formation was 23.4 ± 9.2 days, with a median product application of 1.0. Staged reconstruction was used in 7 of 13 defects, with the remainder (6 of 13) left to heal via secondary intention using standard wound care protocols. There were no major postoperative infections or adverse events (mean follow-up, 7.4 ± 2.4 weeks.). Conclusions: This retrospective pilot case series builds on a growing body of evidence that OFM can be utilized to facilitate the formation of functional, well-vascularized soft tissue in large contaminated volumetric soft tissue defects.

Ovine Forestomach Matrix in the Surgical Management of Complex Lower-Extremity Soft-Tissue Defects.

BACKGROUND: Chronic lower-extremity defects may lead to major amputations and have severe consequences on patient quality of life and mortality. Dermal matrices have become part of the reconstructive ladder and are often deployed in these scenarios to quickly build neodermis, especially in volumetric defects over exposed bone and tendon initially, to allow for subsequent closure by means of split-thickness skin grafting (STSG) or secondary intention. Ovine forestomach matrix (OFM) is a decellularized extracellular matrix (ECM) bioscaffold available in both sheet and particulate forms that can be used as a dermal matrix in various soft-tissue reconstruction procedures. METHODS: This retrospective case series evaluated the use of OFM products in the surgical reconstruction of 50 cases (n = 50) comprised of challenging lower-extremity defects from seven healthcare centers. Patient records were reviewed to identify comorbidities, defect cause, defect size, presence of exposed structures, Centers for Disease Control and Prevention contamination score, Wagner grade, OFM graft use, time to 100% granulation tissue, STSG use, overall time to heal, and postoperative complications. The primary study outcomes were time (days) to 100% granulation tissue formation, with secondary outcomes including overall time to wound closure (weeks), STSG take at 1 week, and complications. RESULTS: The results of this case series demonstrate OFM as a clinically effective treatment in the surgical management of complex lower-extremity soft-tissue defects with exposed structures in patients with multiple comorbidities. One application of OFM products was effective in regenerating well-vascularized neodermis, often in the presence of exposed structures, with a mean time to 100% granulation of 26.0 ± 22.2 days. CONCLUSIONS: These data support the use of OFM as a safe, cost-effective, and clinically effective treatment option for coverage in complex soft-tissue wounds, including exposed vital structures, and to shorten the time to definitive wound closure in complicated patient populations.

Surgical Reconstruction of Stage 3 and 4 Pressure Injuries: A Literature Review and Proposed Algorithm from an Interprofessional Working Group.

OBJECTIVE: Stage 3 and 4 pressure injuries (PIs) present an enormous societal burden with no clearly defined interventions for surgical reconstruction. The authors sought to assess, via literature review and a reflection/evaluation of their own clinical practice experience (where applicable), the current limitations to the surgical intervention of stage 3 or 4 PIs and propose an algorithm for surgical reconstruction. METHODS: An interprofessional working group convened to review and assess the scientific literature and propose an algorithm for clinical practice. Data compiled from the literature and a comparison of institutional management were used to develop an algorithm for the surgical reconstruction of stage 3 and 4 PIs with adjunctive use of negative-pressure wound therapy and bioscaffolds. RESULTS: Surgical reconstruction of PI has relatively high complication rates. The use of negative-pressure wound therapy as adjunctive therapy is beneficial and widespread, leading to reduced dressing change frequency. The evidence for the use of bioscaffolds both in standard wound care and as an adjunct to surgical reconstruction of PI is limited. The proposed algorithm aims to reduce complications typically seen with this patient cohort and improve patient outcomes from surgical intervention. CONCLUSIONS: The working group has proposed a surgical algorithm for stage 3 and 4 PI reconstruction. The algorithm will be validated and refined through additional clinical research.

Influence of advanced wound matrices on observed vacuum pressure during simulated negative pressure wound therapy.

Biomaterials and negative pressure wound therapy (NPWT) are treatment modalities regularly used together to accelerate soft-tissue regeneration. This study evaluated the impact of the design and composition of commercially available collagen-based matrices on the observed vacuum pressure delivered under NPWT using a custom test apparatus. Specifically, testing compared the effect of the commercial products; ovine forestomach matrix (OFM), collagen/oxidized regenerated cellulose (collagen/ORC) and a collagen-based dressing (CWD) on the observed vacuum pressure. OFM resulted in an ∼50% reduction in the observed target vacuum pressure at 75 mmHg and 125 mmHg, however, this effect was mitigated to a ∼0% reduction when fenestrations were introduced into the matrix. Both collagen/ORC and CWD reduced the observed vacuum pressure at 125 mmHg (∼15% and ∼50%, respectively), and this was more dramatic when a lower vacuum pressure of 75 mmHg was delivered (∼20% and ∼75%, respectively). The reduced performance of the reconstituted collagen products is thought to result from the gelling properties of these products that may cause occlusion of the delivered vacuum to the wound bed. These findings highlight the importance of in vitro testing to establish the impact of adjunctive therapies on NPWT, where effective delivery of vacuum pressure is paramount to the efficacy of this therapy.

Use of ovine forestomach matrix in the treatment of facial thermal burns.

INTRODUCTION: Thermal burn injuries are common, devastating medical emergencies that are challenging to manage. Timely and effective treatment is paramount to both short- and long-term patient outcomes. Currently, medical providers and health care facilities worldwide are emphasizing the need for cost-efficient and accessible treatments; such treatments are particularly vital for vulnerable populations with limited access to advanced medical resources. The use of extracellular matrix (ECM) technologies has become widespread in the management of acute and chronic wounds, including burns. Ovine forestomach matrix (OFM) is an ECM bioscaffold isolated from sheep forestomach tissue and has been shown to be effective in soft tissue reconstruction procedures. CASE REPORT: The use of OFM in the treatment of 2 facial thermal burn injuries, including in a pediatric patient, is described. Both patients fully recovered from their facial injuries with satisfactory cosmetic outcomes. CONCLUSIONS: Although OFM technology is widely used in the management of acute and chronic wounds, the authors believe this to be the first published report of its use to aid healing in burns. Ovine forestomach matrix may provide a valuable additional tool for the management of complex burns.

Retrospective real-world comparative effectiveness of ovine forestomach matrix and collagen/ORC in the treatment of diabetic foot ulcers.

The retrospective pragmatic real-world data (RWD) study compared the healing outcomes of diabetic foot ulcers (DFUs) treated with either ovine forestomach matrix (OFM) (n = 1150) or collagen/oxidised regenerated cellulose (ORC) (n = 1072) in out-patient wound care centres. Median time to wound closure was significantly (P = .0015) faster in the OFM group (14.6 ± 0.5 weeks) relative to the collagen/ORC group (16.4 ± 0.7). A sub-group analysis was performed to understand the relative efficacy in DFUs requiring longer periods of treatment and showed that DFUs treated with OFM healed up to 5.3 weeks faster in these challenging wounds. The percentage of wounds closed at 36 weeks was significantly improved in OFM treated DFUs relative to the collagen/ORC. A Cox proportional hazards analysis showed OFM-treated wounds had a 18% greater probability of healing versus wounds managed with collagen/ORC, and the probability increased to 21% when the analysis was adjusted for multiple variables. This study represents the first large retrospective RWD analysis comparing OFM and collagen/ORC and supports the clinical efficacy of OFM in the treatment of DFUs.

Further structural characterization of ovine forestomach matrix and multi-layered extracellular matrix composites for soft tissue repair.

Decellularized extracellular matrix (dECM)-based biomaterials are of great clinical utility in soft tissue repair applications due to their regenerative properties. Multi-layered dECM devices have been developed for clinical indications where additional thickness and biomechanical performance are required. However, traditional approaches to the fabrication of multi-layered dECM devices introduce additional laminating materials or chemical modifications of the dECM that may impair the biological functionality of the material. Using an established dECM biomaterial, ovine forestomach matrix, a novel method for the fabrication of multi-layered dECM constructs has been developed, where layers are bonded via a physical interlocking process without the need for additional bonding materials or detrimental chemical modification of the dECM. The versatility of the interlocking process has been demonstrated by incorporating a layer of hyaluronic acid to create a composite material with additional biological functionality. Interlocked composite devices including hyaluronic acid showed improved in vitro bioactivity and moisture retention properties.

Surgical reconstruction of pilonidal sinus disease with concomitant extracellular matrix graft placement: a case series.

BACKGROUND: Pilonidal sinus disease (PSD) is a chronic inflammatory disease affecting the soft tissue of the sacrococcygeal region and remains a challenging disease for clinicians to treat. The optimal treatment for PSD remains controversial and recent reports describe several different surgical approaches offering different benefits. Approximately 40% of initial incision and drainage cases require subsequent surgery. Due to high recurrence rates and postoperative complications, a more complex revision surgery involving a flap reconstruction may be required. We hypothesised that the combination of an extracellular matrix (ECM) graft with tissue flap reconstruction may decrease the postoperative complications and recurrence rates for PSD. METHOD: We report a retrospective case series using a surgical flap reconstruction with concomitant implantation of an ovine forestomach ECM graft under a fasciocutaneous flap with an off-midline closure for recurrent PSD, where previously surgical intervention had failed due to wound dehiscence and/or recurrent disease. RESULTS: The case series included six patients. After three weeks, all patients except one were fully healed, and the sixth was fully healed by week 4; all wounds remained fully healed at 12 weeks. All patients achieved good cosmesis and were able to return to normal function without any residual symptoms. CONCLUSION: This pilot case series explored augmenting a flap reconstruction for complex PSD with advanced ECM graft materials, demonstrating that it may improve outcomes and minimise typical complications seen in flap closure, such as inflammation, infection, haematoma/seroma and hypoperfusion. Although the study had a limited number of participants, long-term outcomes were promising and suggest that further studies are warranted.