Tissue Reconstruction Research Articles

Carvacrol/cyclodextrin/ceria nanoparticle/hyaluronate hybrid microneedle for promoted diabetic wound healing through the modulation of microenvironment.

Delayed healing due to the persistent microenvironment disorder caused by the hyperglycemia and persistent inflammatory reaction is a core pathological characteristic of diabetic wound. Topical microenvironment modulation represents an important avenue to address delayed healing issue. Microneedles are powerful tools for topical microenvironment modulation as they can effectively deliver therapeutic ingredients into the shallow surface layer of the wound based on their depth-limited tissue penetration capability. Herein, a hybrid microneedle composed of carvacrol (CV), cyclodextrin (CD), mesoporous ceria nanoparticles (MCNs) and hyaluronate (HA) is constructed with objective to modulate the microenvironment within the diabetic wound. The hybrid microneedle is constructed via a two-stage process comprising three stepwise embedding procedures in the first stage and four microneedle casting procedures in the second stage. The physical, chemical and antibacterial performances, as well as the in vitro and in vivo therapeutic potentials, of the hybrid microneedle are evaluated. The therapeutic ingredients, mainly CV and MCNs, incorporated in the microneedle can be readily released into the diabetic wound, and effective microenvironment modulation is realized through the designed antibacterial, antioxidant and anti-inflammatory functions. Consequently, the tissue reconstruction processes including cell proliferation and migration, angiogenesis, and collagen deposition are accelerated due to the improved microenvironment.

Microsurgical Reconstruction of Complex Scalp Defects With Vastus Lateralis Free Flap.

Scalp reconstruction is a challenging field for plastic surgeons. In case of large or complex defects, microsurgical-free flaps are usually required. Reconstructive failure can result in high morbidity and in some cases be life-threatening. In this article, we present our experience in the reconstruction of complex scalp defects with the use of a vastus lateralis (VL) free flap. From July 2013 to July 2023, we retrospectively analyzed patients who underwent soft tissue reconstruction of the scalp with a VL-free flap at the authors' institution. The patient's demographic, clinical and surgical characteristics, and postoperative complications were recorded and analyzed. Thirty patients were included. The mean age was 67.3 years. Seventeen patients were male, while 13 were female. In 56.7% of patients, defects resulted from cancer resection. In four patients, the defect was limited to the soft tissues while a multi-layer defect with bone and/or dura involvement was present in 26 patients. Soft tissue reconstruction was always achieved with a VL-free flap (n = 30). In 28 cases, a skin-grafted muscular flap was used. The most used recipient vessels were the superior thyroid vessels (n = 18). Complications occurred in six patients (20%): two cases of total flap loss and two cases of infection of the cranioplasty materials requiring their removal. In two cases patients died within 48 h. All patients were satisfied with the aesthetic and functional results at 6 months. In the case of complex scalp defects, the gold standard is reconstruction through microsurgical flaps that provide well-vascularized tissue and allow to cover large defects, reducing the incidence of infections and ensuring good brain protection even without cranioplasty. In our experience, VL-free flap represents a valid option, providing a low donor site morbidity, the possibility of a two-team approach, and a low complication rate.

A Pilot Trial of Tongue Reconstruction Using the Chimeric Innervated Vastus Lateralis Muscle and Antero-Lateral Thigh Free Flap.

Subtotal and total glossectomies for advanced tongue cancer result in significant speech- and swallow-related morbidity, impairing quality of life. This prospective pilot study compares the safety and functional outcomes associated with using a chimeric innervated muscle and fasciocutaneous flap for soft tissue reconstruction. A prospective, non-randomized controlled pilot study evaluated a standardized technique for tongue reconstruction using a chimeric innervated vastus lateralis muscle and anterolateral thigh fasciocutaneous flap. Inclusion criteria were ≥ 50% resection of the oral tongue. Participants were followed longitudinally, with measures recorded at baseline, 6-8 weeks, 6 months, and 12 months after surgery. The primary endpoints were post-operative complications, time to radiotherapy, operative time, and locoregional failure, videofluoroscopy swallow studies (dynamic imaging grade of swallowing toxicity (DIGEST), penetration and aspiration score, performance status scale for head and neck). Secondary endpoints were patient-rated outcomes. Eighteen participants were recruited (10 intervention: 8 controls). Fourteen (78%) experienced complications, only one of which was related to the innervated flap. DIGEST scores deteriorated post-operatively across all participants but did not differ significantly between the intervention and control groups (p = 0.4) at any point post-surgery, despite more extensive resections in the intervention group. Those in the intervention group had better patient-rated intelligibility (p = 0.04). Multimodality treatment was associated with worse speech (p = 0.03) and normalcy of diet (p = 0.02). Less extensive resections were associated with better scores in eating in public (p = 0.005), tongue range of movement (p = 0.0008), intelligibility (p = 0.006), and diet (p = 0.001). The innervated vastus lateralis and antero-lateral thigh free-flap technique is safe and improves speech intelligibility for patients with subtotal and total glossectomy defects. However, the technique requires refinement to optimize functional and quality-of-life outcomes.

Robotic Nipple Sparing Mastectomy and Breast Reconstruction with Profunda Artery Perforator Flaps.

The single port robotic nipple sparing mastectomy (SPrNSM) was recently introduced. This approach is safe and has led to favorable outcomes in relation to cosmetic result, patient satisfaction, and breast sensation. The typical reconstruction with all robotic nipple sparing mastectomies is implant based; however, this is not always what a patient desires. We present autologous tissue reconstruction with PAP flaps following SPrNSM using the same axillary incision. A retrospective review of all patients treated with a PAP flap for breast reconstruction and SPrNSM at our institution from July 2022 to May 2023 was performed. Six patients underwent SPrNSM with PAP flap breast reconstruction (three delayed immediate and three immediate reconstruction). Three patients underwent subsequent revision with fat grafting. Breast reconstruction following robotic nipple sparing mastectomy has typically been performed with implants. We present a series of patients treated with PAP flaps for autologous reconstruction utilizing the same remote axillary incision as used in SPrNSM.

Early Initiation of Dangle Protocol in Lower Extremity Free Flap Microsurgery.

Defects of the lower extremity often require free tissue transfer to provide adequate soft tissue reconstruction. Patients typically undergo a postoperative dangle protocol to condition the flap to withstand the increase in venous pressure. The purpose of this study was to evaluate the safety and postoperative length of stay after early initiation of dangle. A retrospective review of patients undergoing lower extremity free tissue transfer reconstruction at the Grady Memorial Hospital from 2012 to 2022 was conducted. Patient demographics, surgical characteristics, and outcomes were analyzed. Patients were categorized into two groups: early (within 5 days after surgery) and late dangle (day 6 or greater). Univariate and multivariate statistical analyses were performed, with significance determined to be p < 0.05. A total of 83 of 99 available patients met inclusion criteria; 22 patients underwent early and 61 late dangle. Free flap survival was 90.9% in the early and 90.2% in the late group. The mean postoperative length of stay in the early and late groups were 12.3 and 18.8 days, respectively (p = 0.0018). There was no difference in the number of patients who had wound healing complications, flap failure, and a need for amputation in each group. Our results demonstrate that initiation of an early dangle protocol does not affect surgical outcome and leads to a reduction in postoperative length of stay. These results can be used to inform evidence-based recommendations for flap management in lower extremity reconstruction.

Application of DynaCT biliary soft tissue reconstruction technology in diagnosis and treatment of hepatolithiasis.

Hepatobiliary stone disease involves an intrahepatic bile duct stone that occurs above the confluence of the right and left hepatic ducts. One-step percutaneous transhepatic cholangioscopic lithotripsy (PTCSL) using the percutaneous transhepatic one-step biliary fistulation (PTOBF) technique enables the clearing of intrahepatic stones and the resolution of strictures. However, hepatolithiasis with associated strictures still has high residual and recurrence rates after one-step PTCSL. DynaCT can achieve synchronized acquisition with a flat-panel detector during C-arm rotation. The technical approach and application value of DynaCT biliary soft tissue reconstruction technology for the diagnosis and treatment of hepatolithiasis with bile duct stenosis were evaluated in this study. To explore the value of DynaCT biliary soft tissue reconstruction technology for the diagnosis and treatment of hepatolithiasis with bile duct stenosis, and to assess the feasibility and effectiveness of the PTOBF technique guided by DynaCT biliary soft tissue reconstruction technology. The clinical data of 140 patients with complex biliary stenosis disease combined with bile duct stenosis who received PTOBF and were admitted to the First Affiliated Hospital of Guangzhou Medical University from January 2020 to December 2024 were collected. The patients were divided into two groups: DynaCT-PTOBF group (70 patients) and conventional PTOBF group (70 patients). These groups were compared in terms of the preoperative bile duct stenosis, location of the liver segment where the stone was located, intraoperative operative time, immediate stone retrieval rate, successful stenosis dilatation rate, postoperative complication rate, postoperative reoperation rate, stone recurrence rate, and stenosis recurrence rate. DynaCT biliary soft tissue reconstruction technology was successfully performed in 70 patients. The DynaCT-PTOBF group had a higher detection rate of target bile ducts where bile duct stones and biliary strictures were located than the PTOBF group. Compared with the PTOBF group, the DynaCT-PTOBF group was characterized by a significantly greater immediate stone removal rate (68.6% vs 50.0%, P = 0.025), greater immediate stenosis dilatation success rate (72.9% vs 55.7%, P = 0.034), greater final stenosis release rate (91.4% vs 75.7%, P = 0.012), shorter duration of intraoperative hemorrhage (3.14 ± 2.00 vs 26.5 ± 52.1, P = 0.039), and lower incidence of distant cholangitis (2.9% vs 11.4%, P = 0.49). There were no significant differences between the two groups in terms of the final stone removal rate, reoperation rate, or long-term complication incidence rate. DynaCT biliary soft tissue reconstruction technology guiding the PTOBF technique in patients with hepatolithiasis with bile duct stenosis is feasible and accurate. It may be beneficial for optimizing the preoperative evaluation of the PTOBF technique.

Treatment strategies for soft tissue injuries associated with blunt brachial artery injury.

Blunt brachial artery injuries (BAI) require reconstruction with an extensive vein graft due to the wide area of arterial damage. In the upper arm, safe options for pedicle flaps are limited, and selecting recipient vessels for free-flap surgery is challenging, complicating the treatment of soft tissue injuries associated with blunt BAI. This study aimed to analyze the characteristics and soft tissue reconstruction of blunt BAI and propose treatment strategies for treating associated soft tissue injuries. Patients with blunt BAI who treated between August 2013 and April 2024 were included. Blunt BAI cases were classified into three groups (Type1A, Type1B, and Type2) based on soft tissue injury localization and elbow flexion reconstruction necessity. Patient demographics, treatment details, and treatment outcomes were investigated. Seven patients were included to this study. There were two cases of Type1A, three Type1B, and two Type2. Three cases of Type1B underwent soft tissue reconstruction using pedicled latissimus dorsi flap and concurrent reconstruction of the elbow flexion. One case of Type2 was treated with free latissimus dorsi flap using AV loop, and the remaining case of Type2 was performed forearm amputation. This study examined the treatment details of seven patients with blunt BAI. If a soft tissue injury is localized to the upper arm, it can be treated with a pedicle flap. However, if the damage extends beyond the forearm, a free flap is essential and some ingenuity is required to select the recipient blood vessel.

Comparison of sensory recovery between random pattern flap and axial pattern flap in finger defect reconstruction

Background: This study aimed to investigate the association between the use of different flaps, including random- and axial-pattern flaps, and sensory recovery following finger soft tissue reconstruction using local pedicle flaps. Methods: A longitudinal study was conducted on 115 patients with 130 finger soft tissue defects treated with local pedicle flaps between December 2016 and December 2020. Assessments were made at early postsurgery (119 flaps), three months postsurgery (110 soft tissue defects), and six months postsurgery (94 soft tissue defects). Sensory recovery outcomes were compared between soft tissue defects reconstructed using random- and axial-pattern flaps. Results: In the early postsurgery period, there was a significantly higher prevalence of a static sense of two-point discrimination (s2PD) ≤6 mm among fingers with random-pattern flaps (96.2%) than among fingers with axial-pattern flaps (64.5%). The probability of s2PD ≤ 6 mm at the donor and recipient sites with the direct flap was 75.5% and 25.5%, respectively, which was significantly higher than that with the reversed flap. After six months, there was a significant difference in sensory recovery compared to that at three months postsurgery, but not between different flap types. Conclusions: Sensory recovery after reconstruction was observed with all flap types, and better sensory recovery can be achieved in a shorter time postsurgery using random-pattern flaps.

Neural Radiance Fields for High-Fidelity Soft Tissue Reconstruction in Endoscopy.

The advancement of neural radiance fields (NeRFs) has facilitated the high-quality 3D reconstruction of complex scenes. However, for most NeRFs, reconstructing 3D tissues from endoscopy images poses significant challenges due to the occlusion of soft tissue regions by invalid pixels, deformations in soft tissue, and poor image quality, which severely limits their application in endoscopic scenarios. To address the above issues, we propose a novel framework to reconstruct high-fidelity soft tissue scenes from low-quality endoscopic images. We first construct an EndoTissue dataset of soft tissue regions in endoscopic images and fine-tune the Segment Anything Model (SAM) based on EndoTissue to obtain a potent segmentation network. Given a sequence of monocular endoscopic images, this segmentation network can quickly obtain the tissue mask images. Additionally, we incorporate tissue masks into a dynamic scene reconstruction method called Tensor4D to effectively guide the reconstruction of 3D deformable soft tissues. Finally, we propose adopting the image enhancement model EDAU-Net to improve the quality of the rendered views. The experimental results show that our method can effectively focus on the soft tissue regions in the image, achieving higher fidelity in detail and geometric structural integrity in reconstruction compared to state-of-the-art algorithms. Feedback from the user study indicates high participant scores for our method.

Potential of Trilayered Gelatin/Polycaprolactone Nanofibers for Periodontal Regeneration: An In Vitro Study.

Over the past few years, biomaterial-based periodontal tissue engineering has gained popularity. An ideal biomaterial for treating periodontal defects is expected to stimulate periodontal-derived cells, allowing them to contribute most efficiently to tissue reconstruction. The present study focuses on evaluating the in vitro behavior of human periodontal ligament-derived stromal cells (hPDL-MSCs) when cultured on gelatin/Polycaprolactone prototype (GPP) and volume-stable collagen matrix (VSCM). Cells were cultured onto the GPP, VSCM, or tissue culture plate (TCP) for 3, 7, and 14 days. Cell morphology, adhesion, proliferation/viability, the gene expression of Collagen type I, alpha1 (COL1A1), Vascular endothelial growth factor A (VEGF-A), Periostin (POSTN), Cementum protein 1 (CEMP1), Cementum attachment protein (CAP), Interleukin 8 (IL-8) and Osteocalcin (OCN), and the levels of VEGF-A and IL-8 proteins were investigated. hPDL-MSCs attached to both biomaterials exhibited a different morphology compared to TCP. GPP exhibited stronger capabilities in enhancing cell viability and metabolic activity compared to VSCM. In most cases, the expression of all investigated genes, except POSTN, was stimulated by both materials, with GPP having a superior effect on COL1A1 and VEGF-A, and VSCM on OCN. The IL-8 protein production was slightly higher in cells grown on VSCM. GPP also exhibited the ability to absorb VEGF-A protein. The gene expression of POSTN was promoted by GPP and slightly suppressed by VSCM. In summary, our findings indicate that GPP electrospun nanofibers effectively promote the functional performance of PDLSCs in periodontal regeneration, particularly in the periodontal ligament and cementum compartment.

Acellular Adipose Matrices Seem to Be an Effective and Safe Strategy for Soft Tissue Regeneration and Volume Restoration: A Systematic Review of Clinically Relevant Literature.

Significance: Autologous adipose tissue grafting (AAG) can provide soft tissue reconstruction in congenital defects, traumatic injuries, cancer care, or cosmetic procedures; over 94,000 AAG procedures are performed in the United States every year. Despite its effectiveness, the efficiency of AAG is limited by unpredictable adipocyte survival, impacting graft volume retention (26-83%). Recent Advances: Acellular adipose matrices (AAMs) have emerged as a potential alternative to AAG. AAMs include adipose tissue-derived extracellular matrix (ECM) and growth factors (GFs), but not cells. When grafted, AAMs serve as scaffolds with biochemical and biophysical cues for local cell (especially adipocytes) proliferation, regenerating soft tissue, and restoring volume. Being acellular, the AAM is not limited by adipocyte necrosis/apoptosis. Critical Issues: Research on AAM has mostly been conducted on small animal models and with small grafts. Clinically relevant AAM research (large animal models and/or clinical trials) is sparse and limited. To address this gap, we conducted a systematic review of clinically relevant AAM literature to assess AAM's clinical efficacy and safety. Across 11 human and 1 porcine study involving reconstructive or cosmetic procedures, we found that AAMs resulted in significant volume retention, adipogenesis, and angiogenesis, without notable adverse effects. Future Directions: Available quantitative and qualitative data suggest that AAM is an effective and safe alternative to AAG. Yet, the current literature is still limited; more robustly designed studies with standardized methods to assess outcomes will help validate these positive preliminary findings, and possibly pave the way for a broader clinical adoption of AAM.

Lower Extremity Soft Tissue Defect Reconstruction Using the SCIP Free Flap: A Comprehensive Review

The reconstruction of lower extremity soft tissue defects requires a flap capable of covering vital foot structures while withstanding the stresses of walking and shoe pressure. The Superficial Circumflex Iliac Artery Perforator (SCIP) flap provides finely detailed tissue and minimal donor site sequelae. Its surgical technique is safe, accessible, and benefits from preoperative echo-Doppler mapping for enhanced precision. The SCIP flap's numerous advantages make it an essential component in the plastic surgeon's decision-making algorithm for lower extremity soft tissue reconstruction, offering a renewed perspective on inguinal donor site management.

Alternating electrical fields to stimulate osteogenic cells and biomimetic calcium phosphate-coated titanium substrates-A combinatorial approach to bone regeneration.

Biophysical stimuli such as alternating electrical fields can mimic endogenous electrical potentials and currents in natural bone. This can help to improve the healing and reconstruction of bone tissue. However, little is known about the combined influence of biomaterials and alternating electric fields on bone cells. Therefore, this study aimed to investigate the impact of both, biomaterials and alternating electric fields, on osteoblast as well as osteoclast differentiation. Initially, either RAW 264.7 or MC3T3-E1 cells were seeded on Ti6Al4V substrates as a load-bearing implant material, modified with biomimetic calcium phosphate (BCP), or uncoated as a reference. The cells were stimulated towards osteoclastic and osteoblastic differentiation via respective growth factors. The effects of BCP substrate modification on cell differentiation were examined after 7days for RAW 264.7 and after 14days for MC3T3-E1 cells. In a further series of tests, either RAW 264.7 or MC3T3-E1 cells were seeded on BCP-modified Ti6Al4V substrates, stimulated towards differentiation using growth factors, and further electrically stimulated via alternating electric fields of different voltages and frequencies. In parallel to the first test series RAW 264.7 and MC3T3-E1 cells were stimulated for 7 and 14days, respectively. Cell morphology was examined via scanning electron microscopy. Cell viabilities were assessed via WST-8 assay. Electrically stimulated MC3T3-E1 cell orientation was evaluated based on fluorescence microscopy images. Marker genes were examined via qPCR. While BCP increased osteoclast-specific gene expression, it had the opposite effect on osteoblast-related genes compared to respective cells seeded on uncoated Ti6Al4V substrates. ES with different parameters showed a broad cellular response due to electrocoupling. While cell viability assessments and gene expression analyses showed clear differences between ES samples and unstimulated controls, only minor cell morphology and orientation differences were observed. Furthermore, there was no clear trend towards a dominant influence of either voltage or frequency as control parameters. Further studies were initiated to investigate the underlying intracellular mechanisms targeted by ES. This work provides an introduction to the targeted control of cellular processes using defined electric fields. The optimization of voltage and frequency could provide therapeutic windows to control specific cellular functions and potentially improve bone regeneration and remodeling processes.

Geometric Reconstruction of Cartilage Tissue With Mesenchymal Stem Cell-Assisted Electromechanical Reshaping: An Experimental Study.

Shaping the ear cartilage and preserving the shape are important and quite difficult. The aim of this study was to demonstrate the effectiveness of the Wharton's jelly-derived stem cell-assisted electromechanical reshaping method in a rabbit ear cartilage defect model and to compare it with surgical reshaping.For the purpose of 25 × 4-mm cartilage defect reconstruction, 48 rabbit ears were divided into 2 main groups according to the shaping method, and these main groups were divided into 3 subgroups according to stem cell injection: control, sham, and stem cell.A rabbit ear cartilage defect was created, and rib cartilage was collected for reconstruction. Although electromechanical reshaping was performed in accordance with the rabbit ear geometry angle, surgical scoring and suturing were performed in the classical method. Stem cells were applied in the first week, and the grafts were removed in the first month. Analyses included angular change, weight change, and histopathology.In this study, electromechanical reshaping was histopathologically similar to surgical reshaping and is more effective in preserving the shape. Cartilage thickness and weight were higher in stem cell groups.Electromechanical reshaping is emerging as an effective and standardized method to maintain cartilage stability and geometry and offers a viable alternative to classic surgical techniques. In addition, stem cell application gave physical strength to cartilage. It is a method that allows us to obtain more stable and more durable cartilages that maintain given shape with the combination of Wharton jelly-assisted electromechanical reshaping method.

Predicting inflammatory response of biomimetic nanofibre scaffolds for tissue regeneration using machine learning and graph theory.

Tissue regeneration after a wound occurs through three main overlapping and interrelated stages namely inflammatory, proliferative, and remodelling phases, respectively. The inflammatory phase is key for successful tissue reconstruction and triggers the proliferative phase. The macrophages in the non-healing wounds remain in the inflammatory loop, but their phenotypes can be changed via interactions with nanofibre-based scaffolds mimicking the organisation of the native structural support of healthy tissues. However, the organisation of extracellular matrix (ECM) is highly complex, combining order and disorder, which makes it difficult to replicate. The possibility of predicting the desirable biomimetic geometry and chemistry of these nanofibre scaffolds would streamline the scaffold design process. Fifteen families of nanofibre scaffolds, electrospun from combinations of polyesters (polylactide, polyhydroxybutyrate), polysaccharides (polysucrose, carrageenan, cellulose), and polyester ether (polydioxanone) were investigated and analysed using machine learning (ML). The Random Forest model had the best performance (92.8%) in predicting inflammatory responses of macrophages on the nanoscaffolds using tumour necrosis factor-alpha as the output. CellProfiler proved to be an effective tool to process scanning electron microscopy (SEM) images of the macrophages on the scaffolds, successfully extracting various features and measurements related to cell phenotypes M0, M1, and M2. Deep learning modelling indicated that convolutional neural network models have the potential to be applied to SEM images to classify macrophage cells according to their phenotypes. The complex organisation of the nanofibre scaffolds can be analysed using graph theory (GT), revealing the underlying connectivity patterns of the nanofibres. Analysis of GT descriptors showed that the electrospun membranes closely mimic the connectivity patterns of the ECM. We conclude that ML-facilitated, GT-quantified engineering of cellular scaffolds has the potential to predict cell interactions, streamlining the pipeline for tissue engineering.

Midface Degloving Approach for Total Maxillectomy Without Orbital Exenteration: A Case Series.

Evaluate the feasibility of the midface degloving approach (MDA) in total maxillectomy without orbital exenteration (TMWOE) and reconstruction for sino-nasal neoplasms. Retrospective case series. Tertiary referral center. This single-center series included 9 consecutive sino-nasal neoplasm patients who had TMWOE using MDA, free tissue reconstruction, and orbital floor implants (April 2018-Dec 2022) assessing tumor characteristics, margins, and complications. There were 3 female and 6 male patients with a median age of 61 years. The median follow-up was 462 days. There were 7 malignant and 2 benign tumors. The median tumor size was 4.6 cm. There were 7 clear margins and 2 positive margins. Most patients underwent some combination of preoperative and or postoperative therapies. After resection, a variety of free tissue reconstruction was performed. Overall, there were no complications clearly attributable to the midface degloving approach. Flap debulking was required in one patient but no long-term complications were encountered. Midface degloving offers an alternative to the Weber-Ferguson for TMWOE and avoids facial incision while providing adequate exposure to the orbital rim. Patient selection is critical, as tumors extending laterally into the zygomatic arch and infratemporal fossa may not be accessible.

Revisit to Old Friends: Abdominal and Groin Flaps For Upper Extremity Soft Tissue Reconstruction

Revisit to Old Friends: Abdominal and Groin Flaps For Upper Extremity Soft Tissue Reconstruction

Circumflex Scapular Artery Perforator Flap and Its Surgical Refinements in Soft Tissue Reconstruction for Various Regions of the Foot and Ankle in Pediatric Patients.

Reconstruction for various regions of the foot and ankle in pediatric patients remains a challenging topic. This study presents the circumflex scapular artery perforator (CSAP) flap and its surgical refinements for addressing soft tissue defects in various regions of the foot and ankle in pediatrics. Forty-seven patients underwent CSAP flap and its surgical refinements for the reconstruction of foot and ankle defects from 2010 to 2022. Mean age was 6.9 (range 2-14). Defects were observed in the ankle, dorsal foot, heel, and sole. The classic CSAP flap was used in 23 patients, and the CSAP flap with refined techniques was utilized in 24 patients, including double skin paddle, debulking, flow-through, and chimeric CSAP flaps. The size of the CSAP flaps ranged between 4.5 × 4 and 18 × 6.5 cm2. All flaps survived except for one case. The patient suffered total flap necrosis and was treated with a secondary reconstructive surgery. Primary closure of the donor site was achieved in all cases. The average follow-up period was 15.6 months. At the final follow-up, the mean AOFAS score was 93.6 (range 77-100). Mean VAS flap appearance score was 8.1 (range 6-10). Most patients showed satisfactory results. The CSAP flap and its surgical refinements are alternative options for repairing pediatric foot and ankle defects, especially in cases involving large defects around the ankle joint, dorsal foot, and non-weight-bearing regions of the heel and sole.

Promoting Angiogenesis/Osteogenesis by a New Copper/Magnesium Hydroxide Hybrid Nanoparticle: InVitro and InVivo Investigation.

In this study, a new hybrid nanoparticle composed of magnesium hydroxide and copper oxide (Mg(OH)2/CuO) with an optimized ratio of magnesium (Mg) to copper (Cu) was designed and incorporated into a 3D-printed scaffold made of polycaprolactone (PCL) and gelatin. These hybrid nanostructures (MCNs) were prepared using a green, solvent-free method. Their topography, surface morphology, and structural properties were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The fabricated 3D-printed PCL/Gelatin/MCN scaffolds were investigated invitro and invivo. Cell viability tests on murine calvarial preosteoblasts (MC3T3-E1) and human umbilical vein endothelial cells (HUVECs) demonstrated that the scaffolds could induce proper cell proliferation. Additionally, the angiogenic and osteogenic properties of the constructs were evaluated using alkaline phosphatase (ALP) activity, osteogenesis-related, and angiogenesis-related gene expression tests. The invivo study was conducted using a rat calvarial defect model, which confirmed the superior angiogenic and osteogenic properties of the PCL/gelatin/MCN scaffolds compared to PCL/Gelatin and PCL/Gelatin/Mg(OH)2 scaffolds. Overall, the PCL/Gelatin/MCN scaffolds showed promising potential for bone regeneration, particularly for critical-sized defects where proper angiogenesis is essential for tissue reconstruction.

Construction of bFGF/heparin and Fe3O4 nanoparticles functionalized scaffolds aiming at vascular repair and magnetic resonance imaging monitoring

This work develops a bioactive basic fibroblast growth factor (bFGF)/heparin and Fe3O4 nanoparticles (NPs) trifunctionalized degradable construct with the potential of using as a vascular tissue engineering scaffold with the aim of improving vascular repair and regeneration therapy. The covalent modification of heparin onto the poly(lactic acid) (PLA)-gelatin (Gel)-Fe3O4 (PGF) scaffold improves the hydrophilicity of the scaffold. Furthermore, the electrostatic adsorption of bFGF on heparin allows for a more consistent and prolonged release of bFGF in situ, hence increasing the stability and effectiveness of bFGF around the surrounding vascular tissues. The sustained release of bFGF promotes the M2 macrophage polarization, and adhesion and migration of macrophages and endothelial cells (ECs), providing a stable and favorable microenvironment for vascular regeneration. Furthermore, the covalently modified heparin minimizes platelet adhesion on the scaffold surface, potentially contributing to the long-term patency of the vascular tissue engineering scaffold. Including Fe3O4 NPs in the scaffold delays degradation and provides an in vivo magnetic resonance imaging (MRI) effect to monitor the scaffold's location and in vivo degradation. Furthermore, the mild photothermal effect of Fe3O4 NPs plays a facilitating role in bFGF release, immune modulation, and ECs manipulation, therefore contributary to the vascular tissue reconstruction.