Large-sized Defects Research Articles

Extrusion‐Based Additive Manufacturing of Cranial Implants Using High‐Performance Polymers: A Comparative Study on Mechanical Performance and Dimensional Accuracy

Fused filament fabrication (FFF) offers great potential to fabricate patient‐specific implants to treat large size defects resulting from craniectomy. Such cranial implants impose critical requirements on material and design. So far, the field has focused on printing cranial implants from polyetheretherketone (PEEK), which is semicrystalline in nature and, therefore, not ideal for FFF because of warping and nonhomogeneous crystallization. Consequently, this work aims at exploring alternative amorphous high‐performance polymers. The tensile and flexural mechanical properties of printed samples from PEEK, polyetherketoneketone (PEKK), and polyphenylsulfone (PPSU) according to ISO standards are compared. Testing of specimens obtained from three orthogonal build directions reveals nearly isotropic mechanical behavior (e.g. ultimate tensile strength differed no more than 8% between print orientations). This enables printing of patient‐specific cranial implants in vertical orientation with minimal support structures, which result in dimensional accuracies in the clinically acceptable range for craniofacial reconstructions. Mechanical assessment via an in‐house designed indentation set‐up shows that both PEKK and PPSU should be considered valid alternatives to PEEK for cranial implants. This work showcases the maturity of FFF for high‐performance polymers and leverages it for complex patient‐specific geometries such as a cranial implant.

Safety and feasibility of transcatheter closure of atrial septal defects in small children weighing less than 10 kg.

When young patients with an oval fossa defect present early with symptoms of heart failure and pulmonary hypertension, surgical treatment is recommended in small bodyweight rather than transcatheter closure. Outcomes of device closure in consecutive symptomatic children weighing under 10 kg were compared with young children aged below 4 years but weighing above 10 kg. Transthoracic echocardiography under conscious sedation guided the procedure in all without need for balloon sizing, transesophageal echocardiogram, and intubation anaesthesia. Symptoms, anthropometry, shunt ratio, pulmonary pressures, defect and device size, percentage oversizing, device/body weight ratio, complications, and post-procedural growth spurt were compared. Ninety-six patients weighing under 10 kg were compared with 160 patients weighing above 10 kg. In total, 83.3% of patients in the study group and 25% of controls were severely malnourished. The median indexed defect size was 35.2 mm/sq.m and 27.4 mm/sq.m, and the device was oversized by 8.7% and 14.2% in the study group and controls, respectively. The device/body weight ratio was 1.93 in study group and 1.4 in controls. Procedure was successful in all except one patient weighing under 10 kg who had a device embolisation. Both groups showed significant growth spurts and proportion, with severe malnutrition reduced to 42% and 11% in the two groups. Device closure was feasible and safe in patients under 10 kg. Transthoracic echocardiographic imaging on conscious sedation provided adequate guidance. Symptoms and growth significantly improved after intervention. Despite a larger defect size, smaller patients had comparable outcomes. In symptomatic children under 10 kg needing early closure, transcatheter intervention should not be deferred.

Cross-Leg Microvascular Free Anterolateral Thigh Flap as a Safe, Viable, and Reserve Option for Reconstruction in a Vessel-Depleted Limb

AbstractWe present the case of a 36-year-old male patient with a posttraumatic composite defect of the lower two-thirds of the anterior aspect of the left leg with exposed necrotic tibia in an old, neglected type 3b fracture of the tibia of 9-month duration. The options for definitive soft-tissue cover include microvascular free tissue transfer and cross-leg flaps. In trauma cases, the surrounding tissue is usually damaged, and the recipient vessels are frequently implicated, ruling out the use of a microvascular free flap. Cross-leg flaps are unachievable due to large defect sizes and lack of appropriate donor tissue. In this case report, we highlight the use of cross-leg microvascular free anterolateral thigh (ALT) flap cover for the composite leg defect. By presenting our case, we aim to advocate the clinical application of cross-leg free flap surgery in vessel-depleted limbs as a safe and viable option.

Lesion Size Location Dependency on Maximum Pressure in Osteochondral Defects: Experiments and Finite-Element Analysis.

Osteochondral defects (OCDs) in the knee joint have significant clinical implications, particularly regarding contact pressures and pressure distribution. Understanding how these factors are influenced by defect size and location is crucial for developing effective therapeutic strategies. The purpose of this study was to investigate the impact of defect size and location on contact pressures and pressure distribution in the knee joint. It was hypothesized that an increase in defect size would result in elevated contact pressures and alterations in pressure distribution, with specific variations related to defect location. Descriptive laboratory study. The study utilized 6 cadaveric knees, including the patella and fibula, subjected to controlled compressive loading for measuring contact pressures. Simultaneously, computed tomography-based models were created for finite-element analysis (FEA) to investigate the impact of varying defect sizes and locations on contact pressures and pressure distribution in the knee joint, excluding the patellofemoral joint. The study employed analysis of variance to assess contact pressure and defect size association. Comparison between medial and lateral femoral condyles at full extension and 30° flexion angle was performed, followed by post hoc testing. Fisher exact test analyzed peak pressure point location and defect size, categorizing them into medial and lateral. An increase in defect size corresponded with heightened contact pressures on both medial and lateral femoral condyles at full extension (P = .013 for medial and P = .024 for lateral). However, this correlation did not yield significant differences at 30° of flexion (P = .674 for medial and P = .333 for lateral). During mechanical testing, the highest pressures occurred near 5 mm defect dimensions. FEAs showed a significant increase in pressure and circumferential-edge stress with 7-mm defects. Peak contact pressure points shifted laterally with more significant defects. Our study demonstrated the impact of defect size, location, and alignment on knee joint contact pressures. Intervening promptly with defects exceeding 3 mm is crucial, as significant stress levels manifest beyond this threshold. Significant increases in contact pressures were noted with larger defect sizes, particularly between 3 and 10 mm at full extension. Peak pressure points shifted with defect size increments, and alignment variations showed minimal stress variation at 30° compared with 0°. FEA validated increasing contact pressures up to 7 mm defect size, beyond which pressures stabilized or slightly decreased. A concentrated pressure distribution on the medial side was observed. These findings inform our understanding of the biomechanical implications of OCDs. In the field of sports medicine, this research offers valuable insights to clinicians and researchers, elucidating key factors influencing knee joint health and the potential consequences of OCDs.

Pure α-phase (FAPbI3)0.83(MAPbBr3)0.17 powder for efficient perovskite solar cells with enhancing reproducibility

Commercializing perovskite solar cells (PSCs) necessitates achieving high performance and reproducibility. One effective strategy for this is the precise regulation of raw powder components in the precursor solution to create high-quality perovskite films. In this study, explored the impact of various precursor solutions on the crystallinity and photovoltaic performance of α-phase (FAPbI3)0.83(MAPbBr3)0.17 perovskite systems. A synthesis method utilizing a mixed powder (FAPbI3)0.83(MAPbBr3)0.17, designated as P2, was developed to address reproducibility issues in PSCs arising from unbalanced stoichiometric ratios. The resulting P2-based perovskite film exhibited large grain size and minimal defects, leading to PSCs with an impressive power conversion efficiency (PCE) of 21.36 % and an open-circuit voltage (VOC) of 1.142 V. Encouragingly, the P2-based PSCs demonstrated outstanding reproducibility and storage stability, with PCE decay limited to 2.1 % at room temperature over a 21-day period.

Oral Reconstruction with Locoregional Flaps after Cancer Ablation: A Systematic Review of the Literature.

Introduction: The planning of oral reconstruction after tumor resection is a pivotal point for head and neck surgeons. It is mandatory to consider two aspects: the size of the surgical defect and the complexity of the oral cavity as an anatomical region. We offer a review of the literature that focuses on four types of locoregional flaps that can be profitably used for such reconstruction: infrahyoid (IF), nasolabial (NF), platysma (PF), and submental (SF). Methods: The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This systematic review was carried out according to the PICOS acronym through a comprehensive electronic search on PubMed/MEDLINE, Cochrane Library, and Google Scholar databases. For each selected article, we extrapolated eight main parameters, of which all mean values were compared through an ANOVA test. The dimensions of the oral defects were referred to as "small" (<7 cm2), "medium" (7-50 cm2), or "large" (>50 cm2). Results: A total of 139 articles were selected with a total of 5898 patients. The mean ages for each type of flap were not statistically significant (p = 0.30, p > 0.05). Seven sublocations of oral defects were reported: The most common was the tongue (2003 [34.0%] patients), followed by the floor of the mouth (1786 [30.4%]), buccal mucosa (981 [16.6%]), cheek (422 [7.2%]), hard palate (302 [5.1%]), alveolar ridge (217 [3.7%]), and retromolar trigone (187 [3.2%]). The defects were mainly medium-sized (4507 [76.4%] patients), and fewer were small-sized (1056 [17.9%]) or large-sized (335 [5.7%]). Complications were noted, the most frequent of which was flap necrosis, seen in 0.57% of cases. The functional and esthetical results were mainly positive. Conclusions: Locoregional flaps represent a good alternative in medium-sized defects as well as a fairly good alternative in small- and large-sized defects when other options are ruled out.

Staged Excision Technique for Periocular Cutaneous Melanoma: Long-Term Outcomes of the Square Procedure.

To examine the long-term outcome of the staged excision via the square procedure for the treatment of periocular thin cutaneous melanoma. A retrospective chart review of 95 periocular cutaneous melanoma-in-situ and microinvasive melanoma tumors that were treated with the square procedure between April 1, 1994 and December 31, 2018 at the University of Michigan. Demographic and clinical data were evaluated. Of 95 cases, 19 (20%) were atypical junctional melanocytic proliferation with features of early melanoma-in-situ, 63 (66.3%) were melanoma-in-situ and 13 (13.7) were microinvasive melanoma with Breslow depth less than 1 mm. Tumor-free margins were achieved with a median margin of 10 mm (range 5-40 mm). Most cases (68.4%) required multiple excision stages. Surgical revision was necessary in 17.9% of cases and was associated with larger defect size. Local recurrence was noted in 8 patients (8.4%) at a median of 42 months postreconstruction. No tumor characteristics were found to predict recurrence. The square procedure for periocular melanoma offers an 8.4% recurrence rate, consistent with literature reports on similar staged excision approaches. The staged excision provides an excellent option for comprehensive margin review and tumor control with acceptable cosmetic results after reconstruction.

Experimental and numerical investigation of radial displacement of COPV using CT and FPP method

The radial displacement of hydrogen storage composite overwrapped pressure vessel (COPV) is a key factor related to the collapse failure and burst pressure. However, there is still lack of effective method to monitor the radial displacement during the hydrostatic test and service process of the vessels. This paper proposed a method to measure the radial displacement based on fringe projection profilometry (FPP). Hydrostatic test with a composite overwrapped pressure vessel verifies the proposed method. The variation of displacement changing with inner pressures observed in the experiments is in agreement with that obtained from finite element analysis. Also Computed Tomography (CT) scanning is conducted and a widely spread micro defects is found in the composite layer of the cylinder. 78.9% of the total observed defects are small (<1000 mm2). In regions where large-sized defects (>1000 mm2) are concentrated, the total area of defects reaches 16,200 mm2. According to the statistical analysis, the strong correlation is found between the defects area and radial displacement.

Drop in survivorship 13 years after AMIC procedures in aligned knees: A long-term follow-up.

Autologous matrix-induced chondrogenesis (AMIC) showed promising short-term results comparable to microfracture. This study aims to assess the 19-year outcomes of AMIC, addressing the lack of long-term data. Retrospective cohort of 34 knees treated with AMIC underwent a 19-year follow-up. The primary outcome was AMIC survival, considering total knee arthroplasty as a failure event. Survival analysis for factors that were associated with longer survival of the AMIC was also performed. Clinical and radiological outcome scores were analysed for the AMIC group. Twenty-three knees were available for follow-up analysis. Of these, 14 (61%) underwent revision surgery for total knee arthroplasty (TKA). The mean time was 13.3 ± 2.5 years (range: 9-17 years). Secondary outcomes showed that increased age at surgery (hazard ratio [HR]: 1.05; p = 0.021) and larger defect size (HR: 1.95; p = 0.018) were risk factors for failure. Concomitant proximal tibial osteotomy (HR: 0.22; p = 0.019) was associated with longer survival. The remaining nine knees (39%) were analysed as a single group. The mean clinical score atfollow-up of 18.6 ± 0.9 SD years was 79.5 ± 19.7 SD for the Lysholm score, 1.8 ± 1.5 SD for the visual analog scale score, 74.2 ± 22.4 SD for the KOOS scoreand a median of 3 (range: 3-4) for the Tegner activity scale. The mean survival time of 13.3 years indicates the durability of AMIC in properly aligned knees. Nonetheless, despite a 61% conversion to TKA, the knees that persisted until the 19-year follow-up remained stable, underscoring the procedure's longevity and consistent clinical outcomes. Level IV.

VRAM Versus ALT Flap Reconstruction for Large Head and Neck Defects: Does Weight Influence Complication Rate?

Background: Obesity remains a high-level risk factor for various cancers. Yet, some research has shown that higher BMIs may improve survival outcomes, particularly for head and neck squamous cell carcinoma (HNSCC). While this is a clear deviation from the norm, it raises the question of what other effects obesity may have on head and neck cancer patients, including surgical outcomes. Choosing the most appropriate flap for patients can be difficult for even experienced surgeons. Head and neck reconstructive surgeries are no exception to this rule and can be especially challenging. To produce the most favorable outcomes, a physician must be able to combine all flap attributes including donor and recipient site location, flap thickness, as well as each patient's individual risk factors such as prior radiation. Purpose: The purpose of this study was to compare the outcomes of vertical rectus femoris myocutaneous (VRAM) and anterolateral thigh (ALT) flaps in overweight and obese individuals with varying head and neck cancers leaving large-sized defects to the outcomes in normal and underweight patients. Methods: A retrospective chart review was conducted of VRAM and ALT flaps performed over a period of 12 months at our university hospital for large head and neck reconstruction. Results: Of the 17 ALT patients, 80% (4/5) of the underweight patients, 57% (4/7) of the normal weight patients, 50% (1/2) of the overweight patients, and 33% (1/3) of the obese patients experienced complications. Of the 15 VRAM patients, 40% (2/5) of the underweight patients, 83% (5/6) of the overweight patients, and 50% (1/2) of the obese patients experienced complications. Conclusions: In our small sample size, a smaller percentage of obese patients with head and neck cancer who underwent flap reconstruction surgery had complications when undergoing ALT flaps than VRAM flaps, which contrasts with the normal and underweight patients, who had less complications with VRAM flaps than ALT flaps.

The induced membrane technique for the management of infected segmental bone defects.

The aim of the present study was to assess the outcomes of the induced membrane technique (IMT) for the management of infected segmental bone defects, and to analyze predictive factors associated with unfavourable outcomes. Between May 2012 and December 2020, 203 patients with infected segmental bone defects treated with the IMT were enrolled. The digital medical records of these patients were retrospectively analyzed. Factors associated with unfavourable outcomes were identified through logistic regression analysis. Among the 203 enrolled patients, infection recurred in 27 patients (13.3%) after bone grafting. The union rate was 75.9% (154 patients) after second-stage surgery without additional procedures, and final union was achieved in 173 patients (85.2%) after second-stage surgery with or without additional procedures. The mean healing time was 9.3 months (3 to 37). Multivariate logistic regression analysis of 203 patients showed that the number (≥ two) of debridements (first stage) was an independent risk factor for infection recurrence and nonunion. Larger defect sizes were associated with higher odds of nonunion. After excluding 27 patients with infection recurrence, multivariate analysis of the remaining 176 patients suggested that intramedullary nail plus plate internal fixation, smoking, and an allograft-to-autograft ratio exceeding 1:3 adversely affected healing time. The IMT is an effective method to achieve infection eradication and union in the management of infected segmental bone defects. Our study identified several risk factors associated with unfavourable outcomes. Some of these factors are modifiable, and the risk of adverse outcomes can be reduced by adopting targeted interventions or strategies. Surgeons can fully inform patients with non-modifiable risk factors preoperatively, and may even use other methods for bone defect reconstruction.

Hernia diafragmática congénita: relación entre el tamaño del defecto y evolución. Experiencia en un centro de referencia

IntroductionCongenital diaphragmatic hernia (CDH) remains a therapeutic challenge. The surgical classification recommended by the Congenital Diaphragmatic Hernia study group (CDHSG), based on the size of the defect, is used for staging in reference centres. Larger defects are associated with poorer outcomes. Our aim was to describe and compare the morbidity at hospital discharge of newborns who underwent surgical correction of CDH at the Juan P. Garrahan, according to the surgical staging of the defect proposed by the CDHSG. Material and methodsThe study included patients with CDH admitted to the Juan P. Garrahan Hospital between 2012 and 2020, and we analysed the distribution, morbidity and mortality associated with the size of the defect. We carried out a descriptive analysis, calculating measures of central tendency and dispersion, and bivariate and multivariate analyses. ResultsA total of 230 patients with CDH were admitted and 158 underwent surgery. We found that defect sizes C and D sizes were associated with an increased risk of chronic pulmonary disease (CPD) (OR, 5.3; 95% CI, 2.2-13.4; P<.0000), need of extracorporeal membrane oxygenation (OR 3.9; 95% CI, 1.3-12.8; P<.005) and chylothorax (OR, 2.1; 95% CI, 0.8- 6.4; P<.10]. The multivariate analysis revealed that a large defect size (C-D) was independently and significantly associated with CPD (OR 4.19; 95% CI, 1.76-9.95). ConclusionStaging the defect according to de CDHSG classification during surgery allows the application of uniform management criteria and the prediction of patient outcomes and complications during the hospital stay.

Rates and predictors of reimplantation of matrix-induced autologous chondrocyte implantation following first stage cartilage harvest: A cohort study

PurposeTo assess the reimplantation rate and predictors of patients requiring second-staged matrix-induced autologous chondrocyte implantation (MACI) reimplantation after initial first stage cartilage biopsy. MethodsA retrospective review was performed from 2018 to 2022 among patients who underwent only phase I MACI biopsy procedure (biopsy group) or both phase I with transition to phase II implantation of chondrocytes (implantation group) at a single tertiary center. Demographic, qualitative, and quantitative measurements were recorded, and univariate and multivariate regression analysis was performed to assess predictors of ultimately requiring second stage MACI implantation. ResultsA total of 71 patients (51% female, age 27.7 ± 10.6 years (range 12–50)) were included in this study. Eventually, 25 of 71 patients (35.2%) experienced persistence of symptoms after initial MACI biopsy and other concomitant procedures, requiring second-stage implantation. Univariate analysis showed the implantation group compared to the biopsy group had a greater lesion size (5.2 cm2 ± 3.3 vs. 3.3 cm2 ± 1.4, p = 0.024), a higher proportion patients ≥ 26 years of age (76% vs. 43%, p = 0.009), a medial femoral condyle lesion more commonly (33% vs 11%, p = 0.005), were more often female (72% vs. 39%, p = 0.008), and had less often soft tissue repair at time of biopsy (32% vs. 61%, p = 0.020). Backward multivariate logistic regression analysis revealed that size of the lesion (OR 1.43, p = 0.031) and age ≥ 26 years old at time of biopsy (OR 3.55, p = 0.042) were independent predictors of not responding to initial surgery and requiring implantation surgery. ConclusionThis study found that 35% of patients undergoing MACI phase I biopsy harvest eventually required autologous implantation. Independent risk factors for progressing to implantation after failed initial surgery were larger defect size and older age.Level of Evidence: III, Cohort Study.

Lateral incisional hernia. EVEREG registry analysis.

The aim of this study is to analyze the data collected on lateral incisional hernias (LIH) in the National Incisional Hernia Registry (EVEREG) and assess current practices and outcomes in LIH repair. A retrospective cohort study was conducted using LIH data recorded over 10years (2012-2022). Comorbidities, hernia characteristics, short-term complications, and recurrences were studied, along with their association with the type of approach used, either open or laparoscopic, in elective surgery. 1742 LIH cases were studied. According to the EHS classification, these included L1 409 (23.5%), L2 388 (22.3%), L3 565 (32.4%), L4 150 (8.6%) and combined 230 (13.2%). An open approach was performed in 1528 (87.7%) cases and laparoscopic in 214 (12.3%). The median age was 66 ± 12.45years, with a majority of males, 934 (53.6%). The median body mass index was 29 ± 5.18kg/m2. The most observed comorbidity was arterial hypertension (957 patients, 55%). A specialist was present in 638 interventions (56%). The 24-month follow-up was 17.9%, and recurrence in those cases was 27.2%, with a higher incidence when there was no specialist present during the intervention, onlay mesh position, and larger defect size. Surgery for LIH is common, although laparoscopic approach remains infrequent. Furthermore, it is associated with a high percentage of recurrences that increases when there is no specialist in abdominal wall surgery present.

Клинический случай некротизирующего склерита, потребовавший пластики обширного дефекта конъюнктивы и склеры

The article presents a rare case of necrotizing scleritis in a 59-year-old patient at Russian Center for Eye and Plastic Surgery. The patient had suffered for six months from rheumatic episcleritis, complicated by keratitis, iridocyclitis and necrotizing scleritis that did not exclude the presence of Franceschetti – Bischler syndrome. Due to the refractive course and the development pf conjunctival and scleral necrosis, the patient underwent a surgical procedure at his local health facility – conjunctival repair with interrupted sutures. Unfortunately, within a week the conjunctival sutures came apart, given the large size of the conjunctival defect (1.1 sm ×4 mm), the patient underwent reoperation at the Russian Center for Eye and Plastic Surgery – surgical removal of necrotic tissue with the subsequent immobilization and conjunctival closure by allotendinous threads and interrupted sutures. Positive effect was observed. Key words:necrotizing scleritis, keratitis, iridocyclitis, Franceschetti – Bischler syndrome, surgical treatment, allotendinous threads.

Disparities in Healthcare Utilization: An Analysis of Disease Specific and Patient Level Factors in a Congenital Diaphragmatic Hernia Clinic

ObjectivesOur study examines if the disease severity profile of our Congenital Diaphragmatic Hernia (CDH) patient cohort adherent to long-term follow-up differs from patients lost to follow-up after discharge and examines factors associated with health care utilization. MethodsRetrospective review identified CDH survivors born 2005–2019 with index repair at our institution. Primary outcome was long-term follow-up status: “active” or “inactive” according to clinic guidelines. Markers of CDH disease severity including CDH defect classification, oxygen use, tube feeds at discharge, and sociodemographic factors were examined as exposures. ResultsOf the 222 included patients, median age [IQR] was 10.2 years [6.7–14.3], 61% male, and 57 (26%) were insured by Medicaid. Sixty-three percent (139/222) of patients were adherent to follow-up. Seventy-six percent of patients discharged on tube feeds had active follow-up compared to 55% of patients who were not, with similar findings for oxygen at discharge (76% vs. 55%). Kaplan–Meier analysis showed patients with smaller defect size had earlier attrition compared to patients with larger defect size. Other race (Hispanic, Asian, Middle Eastern) patients had 2.87 higher odds of attrition compared to white patients (95% CI 1.18–7.0). Medicaid patients had 2.64 higher odds of attrition compared to private insurance (95% CI 1.23–5.66). ConclusionLoss to follow-up was associated with race and insurance type. Disease severity was similar between the active and inactive clinic cohorts. Long-term CDH clinic publications should examine attrition to ensure reported outcomes reflect the discharged population. This study identified important factors to inform targeted interventions for follow-up adherence. Level of EvidenceLevel III.

Decellularized laser micro-patterned osteochondral implants exhibit zonal recellularization and self-fixing for osteochondral regeneration in a goat model

BackgroundOsteochondral regeneration has long been recognized as a complex and challenging project in the field of tissue engineering. In particular, reconstructing the osteochondral interface is crucial for determining the effectiveness of the repair. Although several artificial layered or gradient scaffolds have been developed recently to simulate the natural interface, the functions of this unique structure have still not been fully replicated. In this paper, we utilized laser micro-patterning technology (LMPT) to modify the natural osteochondral “plugs” for use as grafts and aimed to directly apply the functional interface unit to repair osteochondral defects in a goat model. MethodsFor in vitro evaluations, the optimal combination of LMPT parameters was confirmed through mechanical testing, finite element analysis, and comparing decellularization efficiency. The structural and biological properties of the laser micro-patterned osteochondral implants (LMP-OI) were verified by measuring the permeability of the interface and assessing the recellularization processes. In the goat model for osteochondral regeneration, a conical frustum-shaped defect was specifically created in the weight-bearing area of femoral condyles using a customized trephine with a variable diameter. This unreported defect shape enabled the implant to properly self-fix as expected. ResultsThe micro-patterning with the suitable pore density and morphology increased the permeability of the LMP-OIs, accelerated decellularization, maintained mechanical stability, and provided two relative independent microenvironments for subsequent recellularization. The LMP-OIs with goat's autologous bone marrow stromal cells in the cartilage layer have securely integrated into the osteochondral defects. At 6 and 12 months after implantation, both imaging and histological assessments showed a significant improvement in the healing of the cartilage and subchondral bone. ConclusionWith the natural interface unit and zonal recellularization, the LMP-OI is an ideal scaffold to repair osteochondral defects especially in large animals. The translational potential of this articleThese findings suggest that such a modified xenogeneic osteochondral implant could potentially be explored in clinical translation for treatment of osteochondral injuries. Furthermore, trimming a conical frustum shape to the defect region, especially for large-sized defects, may be an effective way to achieve self-fixing for the implant.

Large facial malignant tumor defect reconstruction using keystone flap: a case report

Background: Facial defects resulting from a large malignant tumor excision are often too extensive for primary closure, necessitating the use of skin flaps or grafts. The challenge is particularly pronounced when the defects occur in the facial region. Deciding how to reconstruct facial defects involves considering various factors, with aesthetics taking precedence over other body parts. The preferred method for closing these defects is ideally by transposing local tissues with similar qualities, especially in cases where primary closure is not feasible due to the size of the defect. Case presentation: A case report study of a 60-years-old female patient referred to H. Adam Malik Hospital and underwent excision of malignant tumor and left with large defect on the right cheek and 2/3 upper &amp; 1/3 lower vermillion. Skin flap techniques, such as the advancement flap, rotation flap, and transposition flap, are useful for closing small defects. When dealing with moderate to large-sized defects, especially in high-tension areas, a combination of flap types may be necessary. Over the past two decades, pedicled perforator flaps, notably the keystone flap design, have gained popularity as a viable option. Understanding facial aesthetic units, subunits, and factors influencing incision/scar placement is crucial for clinicians aiming to achieve the most cosmetically pleasing outcome. Conclusions: The presented case details the successful closure of a sizable cheek defect post squamous cell carcinoma excision surgery, achieved through the utilization of a KPIF Type IIA. Patient showed good flap survival.

Surface blistering and D desorption in high-energy-rate forging W, W-Y2O3, W-TiC exposed to deuterium plasma

Pure tungsten (W) and two representative W alloys of W-1 wt.%Y2O3 and W-0.5 wt.%TiC were subjected to deuterium (D) plasma exposure at a fluence up to 1 × 1026 D/m2 at 400 K to evaluate their surface blistering and D desorption behaviors. Thermal desorption spectroscopy (TDS) results revealed that high-temperature desorption peaks (> 650 K) dominated in HERF-W, whereas the two W alloys featured higher intensities of low-temperature D desorption peaks (< 650 K). Even at a low D implantation fluence of 5 × 1023 D/m2, extensive blisters were evident on the surface of pure W, while no discernible blisters were detected on the surface of W-1 wt.%Y2O3 and W-0.5 wt.%TiC, even with a fluence exceeding 2 × 1025 D/m2. Microstructure analysis indicated that the relatively large grain size and limited intrinsic defects in HERF-W were the primary reasons for the early formation of D-induced blisters and subsequent high-temperature desorption of these trapped D, compared to those of two other W alloys. A focus ion beam (FIB)-SEM technique was employed to explore the mechanisms of blistering. Results revealed that the cavities beneath blisters were primarily located along grain boundaries, and coarse blisters were formed by the merging of several small ones. This work provides insight into the relationships among material microstructures, D-induced blistering and D desorption in W-based materials, thus offering valuable guidance for the design of W materials with high resistance to D-induced damages.

Arterial hypertension in infants with congenital diaphragmatic hernia following surgical repair

Pulmonary hypertension (PH) and cardiac dysfunction are established comorbidities of congenital diaphragmatic hernia (CDH). However, there is very little data focusing on arterial hypertension in CDH. This study aims to investigate the incidence of arterial hypertension in neonates with CDH at hospital discharge. Archived clinical data of 167 CDH infants who received surgical repair of the diaphragmatic defect and survived for > 60 days were retrospectively analyzed. Blood pressure (BP) values were averaged for the last 7 days before discharge and compared to standard BP values for sex, age, and height provided by the AHA in 2004. BP values reaching or extending the 95th percentile were defined as arterial hypertension. The use of antihypertensive medication was analyzed at discharge and during hospitalization. Arterial hypertension at discharge was observed in 19 of 167 infants (11.3%) of which 12 (63%) were not receiving antihypertensive medication. Eighty patients (47.9%) received antihypertensive medication at any point during hospitalization and 28.9% of 152 survivors (n = 44) received antihypertensive medication at discharge, although in 45.5% (n = 20) of patients receiving antihypertensive medication, the indication for antihypertensive medication was myocardial hypertrophy or frequency control. BP was significantly higher in ECMO compared to non-ECMO patients, despite a similar incidence of arterial hypertension in both groups (13.8% vs. 10.1%, p = 0.473). Non-isolated CDH, formula feeding, and minimal creatinine in the first week of life were significantly associated with arterial hypertension on univariate analysis. Following multivariate analysis, only minimal creatinine remained independently associated with arterial hypertension. Conclusion: This study demonstrates a moderately high incidence of arterial hypertension in CDH infants at discharge and an independent association of creatinine values with arterial hypertension. Physicians should be aware of this risk and include regular BP measurements and test of renal function in CDH care and follow-up.What is Known:• Due to decreasing mortality, morbidity is increasing in surviving CDH patients.• Pulmonary hypertension and cardiac dysfunction are well-known cardiovascular comorbidities of CDH.What is New:• There is a moderately high incidence of arterial hypertension in CDH infants at discharge even in a population with frequent treatment with antihypertensive medication.• A more complicated hospital course (ECMO, higher degree of PH, larger defect size) was associated with a higher risk for arterial hypertension.