An immunologically active, adipose-derived extracellular matrix biomaterial for soft tissue reconstruction: concept to clinical trial

Soft tissue reconstruction remains an intractable clinical challenge as current surgical options and synthetic implants may produce inadequate outcomes. Soft tissue deficits may be surgically reconstructed using autologous adipose tissue, but these procedures can lead to donor site morbidity, require multiple procedures, and have highly variable outcomes. To address this clinical need, we developed an “off-the-shelf” adipose extracellular matrix (ECM) biomaterial from allograft human tissue (Acellular Adipose Tissue, AAT). We applied physical and chemical processing methods to remove lipids and create an injectable matrix that mimicked the properties of lipoaspirate. Biological activity was assessed using cell migration and adipogenesis assays. Characterization of regenerative immune properties in a murine muscle injury model revealed that allograft and xenograft AAT induced pro-regenerative CD4+ T cells and macrophages with xenograft AAT additionally attracting eosinophils secreting interleukin 4 (Il4). In immunocompromised mice, AAT injections retained similar volumes as human fat grafts but lacked cysts and calcifications seen in the fat grafts. The combination of AAT with human adipose-derived stem cells (ASCs) resulted in lower implant volumes. However, tissue remodeling and adipogenesis increased significantly in combination with ASCs. Larger injected volumes of porcine-derived AAT demonstrated biocompatibility and greater retention when applied allogeneicly in Yorkshire cross pigs. AAT was implanted in healthy volunteers in abdominal tissue that was later removed by elective procedures. AAT implants were well tolerated in all human subjects. Implants removed between 1 and 18 weeks demonstrated increasing cellular infiltration and immune populations, suggesting continued tissue remodeling and the potential for long-term tissue replacement.

Norwegian Open Fracture Management System: Outcomes After 10 Years Working in Low-Resource Settings in Cambodian Hospitals

Introduction: The treatment of open lower limb fractures represents a major challenge for any trauma surgeon, and this even more so in resource-limited areas. The aim of the study is to describe the intervention, report the treatment plan, and observe the effectiveness of the Norwegian Open Fracture Management System in saving lower limbs in rural settings. Materials and Methods: A retrospective and prospective interventional study was carried out in the period 2011 through 2017 in six rural hospitals in Cambodia. The fractures were managed with locally produced external fixators and orthosis developed in 2007. Based on skills and living locations, two local surgeons and one paramedic without reconstructive surgery experience were selected to reach the top of the reconstructive ladder and perform limb salvage surgeries. This study evaluated 56 fractures using the Ganga Hospital Open Injury Score (GHOIS) for Gustilo-Anderson Type IIIA and Type IIIB open fracture classification groups. Results: The primary success rate in open tibia fractures was 64.3% (95% CI, 50.3 - 76.3). The average treatment time to complete healing for all of the patients was 39.6 weeks (95% CI, 34.8 - 44.4). A percentage of 23.2% (95% CI, 13.4 - 36.7) experienced a deep infection. Fifteen of the patients had to undergo soft tissue reconstruction and 22 flaps were performed. Due to non-union, a total of 15 bone grafts were performed. All of the 56 patients in the study gained limb salvage and went back to work. Conclusion: The given fracture management program proves that low-resource countries are able to produce essential surgical tools at high quality and low price. Treatment with external fixation and functional bracing, combined with high-level training of local surgeons, demonstrates that a skilled surgical team can perform advanced limb salvage surgery in low-resource settings.

Lymphatic Complications Prevention and Soft Tissue Reconstruction after Soft Tissue Sarcoma Resection in the Limbs

Background and Objectives: The definitive treatment of soft tissue sarcomas (STS) requires a radical surgical removal of the tumor, which often leads to large soft tissue defects. When they are located in the limbs, significant damage to the lymphatic pathways is not uncommon. In the present article, we present different techniques aimed at both reconstructing the defect and restoring sufficient lymph drainage, thus preventing short- and long-term lymphatic complications. Materials and Methods: Between 2018 and 2020, 10 patients presenting a soft tissue defect with lymphatic impairment received a locoregional reconstruction by means of either pedicled or free SCIP flap. Seven patients required a second flap to reach a good dead space obliteration. In six cases, we performed an interpositional flap, namely a soft tissue transfer with lymphatic tissue preservation, and in four cases a lymphatic flow-through flap. In all cases, the cause of the defect was STS surgical excision. The average age was 60.5 years old (ranging 39–84), seven patients were females and six were males. Results: All the patients were successfully treated. In two cases, minor post-operative complications were encountered (infected seroma), which were conservatively managed. No secondary procedures were required. The average follow-up was 8.9 months (ranging 7–12 months). No signs of lymphedema were reported during this time. In all cases, complete range of motion (ROM) and a good cosmetic result were achieved. Conclusions: A reconstructive procedure that aims not only to restore the missing volume, but also the lymphatic drainage might successfully reduce the rate of postoperative complications. Both lymphatic interpositional flaps and lymphatic flow-through flaps could be effective, and the right choice must be done according to each patient’s needs.

Safety Profile of Synthetic Elastic Degradable Matrix for Soft Tissue Reconstruction in Foot & Ankle Surgery

Background Augmentation of soft tissue repairs has been helpful in protecting surgically repaired tissues as they heal. FlexBand (Artelon, Marietta, Georgia) is a synthetic, degradable, polycaprolactone-based polyurethane urea (PUUR) matrix that has been investigated and used for soft tissue repair in a variety of settings. The purpose of this study was to evaluate the safety profile of a PUUR matrix in a large cohort of patients undergoing soft tissue repairs about the foot and ankle. Methods A retrospective chart review of consecutive patients who underwent surgery using FlexBand to augment a soft tissue repair was performed to evaluate for major and minor complications related to the PUUR matrix. Results. A total of 105 patients with an average >6 months follow-up were included. The most common procedures were spring ligament repair, Achilles tendon repair, and Brostrom. There were 12 complications. Four major complications occurred with only 1 requiring PUUR matrix removal. Patients with wound complications had a higher body mass index (BMI) and rate of smoking. Conclusion Complication rates involving PUUR matrix in soft tissue foot and ankle reconstruction procedures are low and comparable with historical complication rates. The PUUR matrix is safe for use in a variety of soft tissue procedures about the foot and ankle. Level of Evidence: Level 4, Retrospective case-series

Multiple Free Flap Reconstruction of a Complex Intraoral Defect after Squamous Cell Carcinoma Excision: A Case Report

Background: Squamous cell carcinoma is the most frequent malignant cancer of the oral cavity. Metastasis involvement is one of the most relevant prognostic factors in terms of survival probability. Patients with oral cancers often undergo extensive en bloc resective surgery of the mandible and maxilla, with or without cervical nodal dissection, based on the presence or occult risk of regional metastases. Several factors affect the choice of flap, to recover aesthetics and function. Case Presentation: The case of a 60-year-old man who underwent maxillectomy with neck dissection as well as a reconstruction with a combination of multiple vascularized free flaps is presented. Conclusions: The excellent integration of the free flaps and the total absence of complications led to a high-quality aesthetic and functional performance of the reconstruction obtained through two different flaps. More specifically, the fibular free flap for bone reconstruction allows a two-team approach and maintains an excellent vascularization, even in case of several osteotomies for the maxillary reconstruction as reported. In addition, the use of free radial forearm flap for soft tissue reconstruction permits to obtain long caliber vessels, thus facilitating surgery without repositioning of the patient during surgery and therefore, consequently reducing surgery times.

Soft-tissue coverage for wound complications following total elbow arthroplasty

Background: In patients with total elbow arthroplasty (TEA), the soft-tissue around the elbow can be vulnerable to soft-tissue complications. This study aims to assess the outcomes after soft-tissue reconstruction following TEA. Methods: We retrospectively included nine adult patients who underwent soft-tissue reconstruction following TEA. Demographic data and disease characteristics were collected through medical chart reviews. Additionally, we contacted all four patients that were alive at the time of the study by phone to assess any current elbow complications. Local tissue rearrangement was used for soft-tissue reconstruction in six patients, and a pedicle flap was used in three patients. The median follow-up period was 1.3 years (range, 6 months–14.7 years).Results: Seven patients (78%) underwent reoperation. Four patients (44%) had a reoperation for soft-tissue complications, including dehiscence or nonhealing of infected wounds. Five patients (56%) had a reoperation for implant-related complications, including three infections and two peri-prosthetic fractures. At the final follow-ups, six patients (67%) achieved successful wound healing and two patients had continued wound healing issues, while two patients had an antibiotic spacer in situ and one patient underwent an above-the-elbow amputation. Conclusions: This study reports a complication rate of 78% for soft-tissue reconstructions after TEA. Successful soft-tissue healing was achieved in 67% of patients, but at the cost of multiple surgeries. Early definitive soft-tissue reconstruction could prove to be preferable to minor interventions such as irrigation, debridement, and local tissue advancement, or smaller soft-tissue reconstructions using local tissue rearrangement or a pedicled flap at a later stage.

Experience with Flaps After Resection of Vulvar Carcinoma: A Case Series

Background: A defect caused by the radical resection of vulvar cancer requires repair with flap transplantation or vulvoplasty. Therefore, the aim of this study is to present a review of our practice of post-surgical defect reconstruction in cases using different skin flaps.Methods: An observational study was performed among 26 patients with vulvar cancer who were admitted to Sun Yat-Sen Memorial Hospital between February 2015 and February 2020 for surgical and reconstructive procedures. Clinical data of these 26 patients were analyzed. All patients underwent radical resection of vulvar cancer, followed by the repair of post-surgical defects by random flap or axial flap transplantation (even for very complex defects).Results: Among the 26 cases in this study, all patients received 38 soft tissue reconstruction procedures for vulvar perineal defects during the study period. Squamous cell carcinoma was the most commonly diagnosed cancer (80.8%). The average size of the defect was 9.3 ´ 7 cm2. Rhomboid flaps were the most commonly used flaps for performing reconstruction in both the primary and recurrent groups. Poor wound healing was the most commonly discovered complication that occurred in 3 of the 38 flaps (7.9%) used. Previous surgery or radiotherapy did not increase the rate of complications after proper reconstruction was performed.Conclusion: Expanding resection is an effective technique for treating vulvar cancer. Different skin flaps, are effective premium options for post-surgical defect reconstruction, and selective use of skin flaps for treating vulvar defects preserves the vulvar morphology and allows for relatively better functionality.