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ABSTRACTUrban green space (UGS) is important to the urban ecological environment. It has physical characteristics and social function characteristics and plays an important role in urban climate change, sustainable development goals (SDG) and residents’ health. However, existing researches mostly focus on the extraction of UGS physical features, neglecting the importance of UGS social functions, resulting in the unresolved problem of multi-type and fine-grained functional mapping of UGS. Therefore, based on natural language processing (NLP) and multi-source data fusion, this paper proposes a multi-type and fine-grained UGS function mapping method. First, the social functional standards of UGS have been re-established, with a total of 19 categories. Second, the semantic information in the POI data name text is extracted using the deep learning model, and the reclassification of the UGS type of POI data is realized. Then, combined with multi-source data, 18 types of UGS are extracted. Finally, combining multi-source data to extract urban road green spaces (GS), a fine-grained UGS functional map of Shanghai is created. The results show that the overall accuracy rate of the method is 93.6%, and the Kappa coefficient is 0.93, which proves that the method has good performance in large-scale spatial UGS classification.

Fe–Cr alloy powders were prepared by vacuum close-coupled gas atomization technology. The effects of the diameter and protrusion length of the melt delivery nozzle on the size distribution, yield, and median particle size (D50) of the Fe–Cr alloy powders were studied. The results show that, when the diameter of the melt delivery nozzle increases from 4.5 mm to 6.0 mm, the size accumulation distribution curve of the Fe–Cr alloy powders shifts to the right, the median particle size increases, the fine powder yield decreases, the powder fluidity decreases, and the apparent density decreases. When the protrusion length of the melt delivery nozzle increases from 2.0 mm to 2.5 mm, the size accumulation distribution curve of the Fe–Cr alloy powders shifts to the left, the median particle size decreases, the fine powder yield increases, the powder fluidity increases, and the apparent density increases. Combined with the experimental data analysis, the best comprehensive properties of the Fe–Cr alloy powders are obtained under the condition as the atomization pressure of 3.8 MPa, the superheat of 250 ℃, the nozzle diameter of 4.5 mm, and the nozzle protrusion length of 2.5 mm.

Abstract Background Blood nerve barrier (BNB) participates in the development of neuropathic pain. AQP1 is involved in peripheral pain perception and is negatively correlated with HIF-1α phenotype, which regulates endothelial permeability. However, the role of HIF-1α-AQP1-mediated BNB dysfunction in Chronic Postsurgical Pain (CPSP) has not been reported. Methods Male Sprague-Dawley rats were randomized into 5 groups: (i) Naive group; (ii) Sham group; (iii) SMIR group: skin/muscle incision and retraction for one hour. Behavioral tests were performed for the three groups, BNB vascular permeability and western blotting were conducted to determine HIF-1α and AQP1 protein expression. (iv) The SMIR + HIF-1α inhibitor group; (v) SMIR + DMSO group. Rats in the two groups were administered with HIF-1α inhibitor (2ME2) or DMSO intraperitoneally on the third day post-SMIR surgery followed by performance of behavioral tests, BNB permeability assessment, and determination of HIF-1α, AQP1 and NF200 protein levels. Results The permeability of BNB was significantly increased and the expression of AQP1 was downregulated on the 3rd and 7th days post-operation. AQP1 is mainly located in neurons and NF200, CGRP-positive nerve fibers. HIF-1α was highly expressed on the third day post-operation. HIF-1α inhibitor reversed the decrease in AQP1 expression and increase in NF200 expression, barrier permeability and hyperalgesia induced by SMIR on the 3rd day post-surgery. Conclusions Early dysfunction of BNB mediated by HIF-1α/AQP1 activated by SMIR may be an important mechanism to promote acute postoperative painful transformation of CPSP. Preadaptive protection of endothelial cells around nerve substructures may be an important countermeasure to inhibit CPSP transformation. Early impairment of BNB function mediated by HIF-1α/AQP1 activated by SMIR may be an important mechanism for promoting acute postoperative pain transformation of CPSP.

Alzheimer’s disease (AD) is a common dementia and a heterogeneous disease. Previous research has validated that microRNAs (miRNAs) are pivotal regulators in the initiation and development of tremendous diseases including AD. MicroRNA-485-5p (miR-485-5p) was reported to be an important participant implicated in several neurological diseases, but its role in AD still needs to be further investigated. In this research, we explored the biological function of miR-485-5p in AD. RT-qPCR revealed that miR-485-5p expression was downregulated in the hippocampus of APP/PS1 mice. Additionally, miR-485-5p overexpression facilitated the learning and memory capabilities of APP/PS1 mice according to Morris water maze test, fear conditioning test, and immunofluorescent staining. Moreover, CCK-8 assay, flow cytometric analysis, and western blot analysis suggested that miR-485-5p overexpression promoted pericyte viability and prohibited pericyte apoptosis in APP/PS1 mice. Mechanistically, miR-485-5p directly targeted PACS1 in pericytes, as shown in a luciferase reporter assay. In rescue assays, PACS1 overexpression countervailed the effect of miR-485-5p overexpression on pericyte viability and apoptosis. In conclusion, miR-485-5p ameliorates AD progression by targeting PACS1.

Abstract Background Chimeric antigen receptor T cells (CAR-T cells) therapy has been well recognized for treating B cell-derived malignancy. However, the efficacy of CAR-T cells against solid tumors remains dissatisfactory, partially due to the heterogeneity of solid tumors and T cell exhaustion in tumor microenvironment. PD-L1 is up-regulated in multiple solid tumors, resulting in T cell exhaustion upon binding to its receptor PD-1. Methods Here, we designed a dominant-negative form of PD-1, dPD1z, a vector containing the extracellular and transmembrane regions of human PD-1, and a CAR vector against PD-L1, CARPD-L1z, a vector employs a high-affinity single-chain variable fragment (scFv) against human PD-L1. These two vectors shared the same intracellular structure, including 4-1BB and TLR2 co-stimulatory domains, and the CD3ζ signaling domain. Results dPD1z T and CARPD-L1z T cells efficiently lysed PD-L1+ tumor cells and had enhanced cytokine secretion in vitro and suppressed the growth of non-small cell lung cancer (NSCLC), gastric cancer and hepatoma carcinoma in patient-derived xenograft (PDX). However, the combination of anti-mesothelin CAR-T cells (CARMSLNz T) with dPD1z T or CARPD-L1z T cells did not repress tumor growth synergistically in PDX, as CARMSLNz T cells upregulated PD-L1 expression upon activation and were subsequently attacked by dPD1z T or CARPD-L1z T cells. Conclusions In conclusion, we demonstrate CAR-T cells targeting PD-L1 were effective for suppressing the growth of multiple types of solid tumors in PDX models though their safety needs to be carefully examined.

Purpose. Caveolae (CAV) are an invaginated microcapsule with the shape of Ω on the surface of the cell membrane. Caveolin-1 (CAV-1) is involved in neuropathic pain, and adenosine monophosphate (AMP)-exchange protein directly activated by cAMP1 (EPAC-1) is a potential therapeutic target for chronic pain. However, whether EPAC-1 promotes chronic postsurgical pain (CPSP) through CAV-1 has not been reported. Here, we aim to investigate the underlying mechanism of CAV in CPSP. Methods. All the rats were divided into 9 groups, including the Naive group, Sham group, skin/muscle incision and retraction (SMIR) group, SMIR + CAV-1 siRNA group, SMIR + control siRNA group, SMIR (7 days)+Saline group, SMIR (7 days)+CE3F4 group, 8-PCPT group, and Saline group. The CPSP rat model was established after SMIR. A mechanical withdrawal threshold (MWT) was recorded to evaluate the animal’s behavior. Western blotting and immunofluorescent were performed to detect the protein expression levels of EPAC-1 and P-CAV-1. Results. EPAC-1 and CAV-1 were both overexpressed after operation, particularly in astrocytes, microglia, and neurons of spinal marrow (all P

Taking advantage of faster speed, less resource consumption and better biological interpretability of spiking neural networks, this paper developed a novel spiking neural network reinforcement learning method using actor-critic architecture and temporal coding. The simple improved leaky integrate-and-fire (LIF) model was used to describe the behavior of a spike neuron. Then the actor-critic network structure and the update formulas using temporally encoded information were provided. The current model was finally examined in the decision-making task, the gridworld task, the UAV flying through a window task and the avoiding a flying basketball task. In the 5 × 5 grid map, the value function learned was close to the ideal situation and the quickest way from one state to another was found. A UAV trained by this method was able to fly through the window quickly in simulation. An actual flight test of a UAV avoiding a flying basketball was conducted. With this model, the success rate of the test was 96% and the average decision time was 41.3 ms. The results show the effectiveness and accuracy of the temporal coded spiking neural network RL method. In conclusion, an attempt was made to provide insights into developing spiking neural network reinforcement learning methods for decision-making and autonomous control of unmanned systems.

This article proposes an adaptive flight framework that integrates a discrete-time incremental nonlinear dynamic inversion controller and a neural network (NN)-based observer for maneuvering flight. The framework is built on the feedback-inversion scheme in which the adaptive neural network augments a discrete-time disturbance observer in the loop. The effects of the modeling uncertainties and the exogenous perturbations are both taken into consideration and are alleviated by the observer. By utilizing the Lyapunov synthesis method, the updating rule of the NN’s weights is introduced, which guarantees the system’s stability with enhanced tracking performance. The efficiency of the proposed scheme is presented through numerical verification of a 6-DOF fixed-wing fighter performing several aggressive flight maneuvers. Extensive simulation results illustrate that this versatile controller is more practical for aerobatic flights compared with the discontinuous sliding mode (DSM) and the nonlinear dynamic inversion (NDI) methods. Given well-generated maneuver commands, the aircraft can accurately track the aggressive reference in the presence of modeling perturbations such as changes in aerodynamic coefficient, inertial parameters, and wind gusts.

Using multiple representations is advocated and emphasized in mathematics and science education. However, many students have difficulty connecting multiple representations of linear functions. Augmented Reality (AR) may affect these teaching and learning difficulties by offering dynamically linked representations. Inspired by this, our study aims to develop, implement, and evaluate an AR-based multi-representational learning environment (MRLE) with three representations of linear functions. The data were collected from 82 seventh graders from two high-performing classes in an urban area in China, through a pre-test, a post-questionnaire, and follow-up interviews. The results reveal that students were satisfied with the AR-based MRLE, which assisted in enhancing their understanding of the real-life, symbolic, and graphical representations and connections among them. Regarding students’ interactions with multiple representations, apparent differences in learning sequences and preferences existed among students in terms of their representational learning profile. In sum, learning in the AR-based MRLE is a complex interaction process between the mathematics content, forms of representations, digital features, and students’ representational learning profile.

Caoe River sluice project is located at the Caoe River Estuary on the South Bank of Jianshan River Bay of Qiantang River. The project has comprehensive utilization of moisture-proof (flood), waterlogging control, water resources development and utilization, as well as improving water environment and shipping. The completion of the Cao’e River Sluice Project has improved the flood control capacity of the main stream of the Cao’e River (below the Shangpu sluice), the drainage capacity of the plain of the Cao’e River Basin, and the navigation guarantee rate of the Hangzhou Ningbo canal and the Cao’e River section of the Hangzhou Ningbo canal. The regulation of Cao’e River sluice has an important impact on the above functions. The regulation of Cao’e River Sluice depends on the accurate analysis of rainfall. Therefore, this paper analyzes the rainfall in the area where the Cao’e River sluice is located, and finds that it has a long period of 34 years and a small period of 20 years, and will be in a dry period in the next few years.

Urban parks have important impacts on urban ecosystems and in disaster prevention. They also have diverse social functions that are important to the living conditions and spatial structures of cities. Identifying and classifying the different types of urban parks are important for analyzing the sustainable development and the greening progress in cities. Existing studies have predominantly focused on the data extraction of urban green spaces as a whole, while there have been relatively few studies that have considered different categories of urban parks and their impact, which makes it difficult to characterize or predict the spatial distribution and structures of urban parks and limits further refinement of urban research. At present, the classification of urban parks relies on the physical features observed in remote sensing images, but these methods are limited when mapping the diverse functions and attributes of urban parks. Crowd-sourced geographic data may more accurately express the social functions of points of interest (POIs) in cities, and, therefore, employing open data sources may assist in data extraction and the classification of different types of urban parks. This paper proposed a multi-source data fusion approach for urban park classification including POI and urban functional zone (UFZ) data. First, the POI data were automatically reclassified using improved natural language processing (NLP) (i.e., text similarity measurements and topic modeling) to establish the links between urban park green-space types and POIs. The reclassified POI data as well as the UFZ data were then subjected to scene-based data fusion, and various types of urban parks were extracted using data attribute analysis and social attribute recognition for urban park mapping. Experimental analysis was conducted across Beijing and Hangzhou to verify the effectiveness of the proposed method, which had an overall classification accuracy of 82.8%. Finally, the urban park types of the two cities were compared and analyzed to obtain the characteristics of urban park types and structures in the two cities, which have different climates and urban structures.

More and more gas reciprocating generator units are integrated into offshore platforms, due to their compact structure and high efficiency. This paper concentrates on the transient stability analysis of one special type of AC microgrids containing a gas reciprocating generator unit. Firstly, the operation principle for the gas reciprocating generator unit is presented, which mainly consists of a reciprocating internal combustion engine and a linear synchronous alternator (LSA). Afterwards, the mathematical model for the core part of the gas reciprocating generator unit LSA is proposed, based on the principle of armature reaction in traditional synchronous and asynchronous machines. Finally, the simplified model of the independent offshore power system with a gas reciprocating generator unit is derived, and numerical simulations on the transient stability of this typical AC microgrid are performed, from which the effectiveness and correctness of the LSA model are validated. The transient stability analysis method of the independent offshore power system and the mathematical model of LSA can provide beneficial guidance for the stable operation of other types of stand-alone AC microgrids.

Puyang river basin is located in the north central part of Zhejiang Province, which is one of the most important river basins in Zhejiang Province. The lower reaches of Puyang River are easily influenced by tide in Hangzhou Bay and flood in Qiantang River. When Puyang river floods, it often meets Fuchun River and floods occur at the same time. The flood discharge of Puyang river is blocked and the water level rises and rises, which makes the Puyang River vulnerable to disaster. Water level frequency analysis is the basis of Puyang river planning and flood control plan. The representative flood control water level stations of Puyang River include Zhuji station and wenjiayan station. The frequency analysis of these representative stations is helpful to determine the water level of these key nodes under different frequencies, and to provide basic data for accurate flood control of Puyang River and ensure the safety of flood control.

Commutation failure is a key issue that affects the safe operation of HVDC transmission systems. Scholars at home and abroad have conducted research on the mechanism, evaluation indicators, and control strategies of commutation failure. However, most of the researches are aimed at the working conditions of commutation failure caused by a short-circuit fault on the AC side. There are few studies on the commutation failure caused by the harmonic injection on the AC side and the distortion of the AC bus voltage waveform. This paper clarifies the mechanism of commutation failure caused by waveform distortion, and proposes an index of harmonic commutation margin. On this basis, an evaluation method for commutation failure caused by waveform distortion is proposed. By predicting the commutation voltage-time area and optimization methods to assess whether the current voltage conditions have the risk of commutation failure. Finally, an electromagnetic transient simulation model is established on PSCAD/EMTDC, and the evaluation method in this chapter is verified by simulating the working conditions of the inverter side bus voltage waveform distortion. The results show its effectiveness in evaluating the commutation failure. The research provides a theoretical basis to the implementation of the control function and has broad engineering application prospects.

The feasibility of battery energy storage system (BESS) in ameliorating power system transient stability has been proved. However, the required BESS capacity is large, which leads to high price. Meanwhile, the improving effect is significantly affected by fault location and BESS location. To address the problem, a distributed configuration of BESS, with a coordinated control method, is proposed in this paper. Firstly, an independent double-closed loop decoupling controller is designed for each BESS, so that the BESS unit can realize decentralized control according to its local correlation information. Secondly, particle swarm optimization is applied to optimize the control parameters of the distributed controllers to achieve coordinated control. Simulation results show that the distributed BESS controllers optimized by particle swarm optimization can better coordinate with each other, and the transient stability of the system is significantly improved.

Photovoltaic power output forecast error exists objectively and inevitably, and it can provide a guarantee for safe and stable operation of the power system through analyzing its characteristics. In this paper, the influence of predicted output fluctuation characteristics (predicted output amplitude and power variation) on prediction error was studied based on the analysis of variance (ANOVA) method. The prediction error conditions were classified into six types based on the clustering of numerical characteristics of predicted output. Then, a Generalized Gaussian Mixture Model (GGMM) was proposed to fit the prediction error distribution of each type of photovoltaic output. The mean absolute error (MAE), coefficient of determination (R2), and root mean square error (RMSE) were used as accuracy evaluation indexes. The example analysis showed that the GGMM can satisfy the asymmetry and kurtosis diversity of the error distribution after division by conditions, and the fitting result is better than that of the normal distribution, improved Laplace distribution and t Location-Scale distribution model.

Chronic postsurgical pain (CPSP) is a chronic pain state that is difficult to be treated clinically. A series of complicated changes have been produced from nociceptive stimulation to the occurrence and development of postsurgical pain. Many mechanisms remain unclear. In order to study the role of intercellular gap junctions in inducing inflammatory microenvironment at the beginning of nociceptor after operation, the model of skin/muscle incision and retraction (SMIR) was established. We observed the changes of the expression of exchange proteins directly activated by cAMP-1 (Epac1) and p120 catenin (p120), the quantities of macrophages and endothelial cells, vascular endothelial permeability, and mechanical withdrawal threshold (MWT). It was found that macrophages and endothelial cells were functionally coupled through Epac1-p120. Adhesive linkage disorder remodeled the chronic, inflammatory, and eutrophic microenvironment at the beginning of nociceptor after operation through macrophages, endothelial cells, and endothelial paracellular pathways. It might be an early event and a key step in peripheral sensitization of CPSP. The expression of p120 in muscle tissue around the incision might become a prognostic marker for the conversion of acute postsurgical pain into CPSP. Targeted intervention of Epac1-p120 might be a clinical strategy for inhibiting the conversion of acute postsurgical pain into CPSP.

Considering the dynamics model parameter uncertainty and external disturbance of four-wheeled omnidirectional mobile robot,a kind of four- wheeled omnidirectional mobile robot trajectory tracking control method based on adaptive sliding mode is put forward in order to improve the trajectory tracking control performance. Firstly,the robot dynamics model is established on the basis of drive motor parameters. And an adaptive sliding mode trajectory tracking controller is designed. At the same time a parameter adaptive control algorithm is proposed in order to achieve the online estimation of the robot dynamics parameters,and real- time switch gain adjustment of trajectory tracking controller is achieved by using RBF neural network as to reduce the chattering of the system. Finally,the simulation experiment is carried out by using MATLAB in order to verify the effectiveness of the described method. The simulation results show that the four- wheeled omnidirectional mobile robot trajectory tracking method based on adaptive sliding mode control can well reduce the effects of parameter variations and external disturbances on the system. It can reduce the chattering of the system and has good anti- interference ability.

This paper presents a hybrid topology optimization method for multipatch fused deposition modeling (FDM) 3D printing to address the process-induced material anisotropy. The ‘multipatch’ concept consists of each printing layer disintegrated into multiple patches with different zigzag-type filament deposition directions. The level set method was employed to represent and track the layer shape evolution; discrete material optimization (DMO) model was adopted to realize the material property interpolation among the patches. With this set-up, a concurrent optimization problem was formulated to simultaneously optimize the topological structure of the printing layer, the multipatch distribution, and the corresponding deposition directions. An asynchronous starting strategy is proposed to prevent the local minimum solutions caused by the concurrent optimization scheme. Several numerical examples were investigated to verify the effectiveness of the proposed method, while satisfactory optimization results have been derived.

Background: Arthroscopy remains a commonly performed procedure in patients who have meniscal or other osteochondral pathology prior to ultimately being indicated for unicompartmental knee arthroplasty (UKA). The purpose of this study was to examine the timing of knee arthroscopy prior to UKA and its association with 2-year periprosthetic joint infection (PJI) rates and medical and surgical complications., Methods: Patients undergoing UKA who had history of ipsilateral arthroscopy within 2 years prior to the UKA were identified in a national insurance database. A control cohort of propensity matched patients who did not have a history of arthroscopy was identified. Study cohorts were established based on timing of the arthroscopic procedure: 0 to 3, 3 to 6, 6 to12, and 12 to 24 months prior to UKA. Patients were included if they had 2-year postoperative follow-up after UKA. The 90-day rates of postoperative medical and 2-year surgical complications were recorded. Multivariate analysis was conducted to account for confounding variables and covariates., Results: A final cohort of 3,471 patients met inclusion criteria. Patients undergoing UKA within three months of the arthroscopic procedure demonstrated a higher incidence of PJI when compared to the control cohort (3.30 versus 1.12%, P = 0.012). In addition, there was an increased rate of periprosthetic fracture observed in those undergoing UKA within three months of arthroscopy when compared to the control (1.10 versus 0.20%, P = 0.010)., Conclusions: Patients undergoing ipsilateral arthroscopy within three months of a UKA demonstrated a nearly 3-fold increased incidence of PJI when compared to the control. There was no increased incidence of PJI when UKA was staged greater than three months after arthroscopy. These findings provide insight for preoperative considerations for arthroplasty surgeons in this patient population., Level of Evidence: Level III, retrospective comparative study., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Femoroacetabular impingement (FAI) is one of the most common causes of labral and early cartilage damage in the nondysplastic hip. FAI is increasingly recognized as a cause for hip and groin pain in the young, active patient, and the surgical treatment of FAI with hip arthroscopy has risen exponentially. Although our understanding of FAI and the progression to degenerative osteoarthritis of the hip has historically been considered a mechanical "wear-and-tear" disease of an imperfectly shaped, aspherical, femoral head within a deep or overcovering acetabulum leading to cartilage injury, our understanding of the intrinsic pathophysiologic mechanisms underlying the development of FAI and joint degeneration of the hip remains poor. For example, many patients with FAI morphology may never develop hip pain or osteoarthritis; there remains more to discover regarding the pathophysiology of arthritis in the setting of FAI. Recent work has begun to identify a strong inflammatory and immunologic component to the FAI disease process that affects the hip synovium, labrum, and cartilage and may be detectable from peripheral clinical samples (blood and urine). This review highlights our current understanding of the inflammatory and immunologic contributions to FAI and potential therapeutic strategies to supplement and augment the surgical management of FAI., (Copyright © 2023 by the American Academy of Orthopaedic Surgeons.)

Background: Costimulatory blockade-induced allograft tolerance has been achieved in rodent models, but these strategies do not translate well to nonhuman primate and clinical transplants. One confounder that may underlie this discrepancy is the greater ischemic inflammation imposed on the transplants. In mice, cardiac allografts subjected to prolonged cold ischemic storage (CIS) before transplant have increased ischemia-reperfusion injury, which amplifies infiltrating endogenous memory CD8 T-cell activation within hours after transplantation to mediate acute graft inflammation and cytotoxic lymphocyte-associated molecule-4 immunoglobulin-resistant rejection. This study tested strategies inhibiting memory CD8 T-cell activation within such high ischemic allografts to achieve long-term survival., Methods: A/J (H-2 a ) hearts subjected to 0.5 or 8 h of CIS were transplanted to C57BL/6 (H-2 b ) recipients and treatment with peritransplant costimulatory blockade. At 60 d posttransplant, regulatory T cells (Treg) were depleted in recipients of high ischemic allografts with anti-CD25 monoclonal antibody (mAb) or diphtheria toxin., Results: Whereas peritransplant (days 0 and +1) anti-lymphocyte function-associated antigen-1 mAb and anti-CD154 mAb prolonged survival of >60% allografts subjected to minimal CIS for >100 d, only 20% of allografts subjected to prolonged CIS survived beyond day 80 posttransplant and rejection was accompanied by high titers of donor-specific antibody. Peritransplant anti-lymphocyte function-associated antigen-1, anti-tumor necrosis factor-α, and anti-CD154 mAb plus additional anti-CD154 mAb on days 14 and 16 obviated this donor-specific antibody and promoted Treg-mediated tolerance and survival of 60% of high ischemic allografts beyond day 100 posttransplant, but all allografts failed by day 120., Conclusions: These studies indicate a strategy inducing prolonged high ischemic allograft survival through Treg-mediated tolerance that is not sustained indefinitely., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Ulnar collateral ligament (UCL) reconstruction of the medial elbow is considered to be the gold standard for treating valgus instability seen in overhead throwing athletes. The first UCL construction was performed by Frank Jobe in 1974, and this procedure has evolved over time to include multiple techniques that improved the biomechanical strength of the graft fixation and maximize the rate of return to athletic competition for these patients. The most common UCL-reconstruction technique used today is the docking technique. The purpose of this Technical Note is to describe our technique, including pearls and pitfalls, which combines the many advantages of the docking technique with a proximal single-tunnel suspensory fixation technique. This method allows for optimal tensioning of the graft, allowing for secure fixation that relies on metal implants as opposed to tying sutures over a proximal bone bridge., (© 2023 The Authors.)

Purpose: To define the anatomical relationship of the major neurovascular structures to the standard endoscopic portals used in endoscopic hamstring repair. A secondary outcome was to determine the safest angle of insertion from each standard portal., Methods: Endoscopic portals were established in the 3 standard locations (lateral, medial, and inferior) and Steinmann pins inserted at various angles. Each hip was dissected and the distance between the pins and the pertinent anatomy measured., Results: The lateral portal placed the sciatic and posterior femoral cutaneous (PFC) nerves at greatest risk: direct injury to the sciatic nerve was seen in 11/30 (37%) of the lateral portals sited. A lateral portal with an approach at 60° was the most dangerous orientation with a mean distance of 0.36 ± 0.49 mm and 4.30 ± 2.69 mm from the sciatic and PFC nerves, respectively ( p < 0.001). The 60° medial portal was the safest of all portals measured, at a mean distance of 67.37 ± 11.06mm (range, 47-78 mm) from the sciatic nerve and 58.90 ± 10.57 mm (range 40-70 mm) from the PFC nerve., Conclusions: While currently described techniques recommend establishing the standard lateral portal first, this study shows that it carries the highest risk of injury if used blind. We recommend that the standard medial endoscopic portal is established first to identify the neurovascular structures and minimise iatrogenic neurovascular injury. The inferior and lateral portals can then be established created under direct vision. The lateral portal should be inserted in a more horizontal orientation to decrease the risk of nerve injury.

Astronomical increases in medical expenses and waste produce widespread financial and environmental impacts. Minor changes to minimize costs within orthopaedics, the most used surgical subspecialty, could result in substantial savings. However, few orthopaedic surgeons are educated or experienced to implement cost containment strategies. This study aims to investigate cost containment opportunities and provide a framework for educating and incorporating residents into cost-saving initiatives., Methods: Orthopaedic surgical residents from an academic program with a Level I trauma center were queried during 2019 to 2022 regarding suggestions for cost containment opportunities. Based on feasibility and the estimated impact, 7 responses were selected to undergo cost-saving analyses., Results: The proposed initiatives fell into 2 categories: minimizing waste and optimizing patient care. Eliminating nonessential physical therapy/occupational therapy consults led to the greatest estimated savings ($8.6M charges/year), followed by conserving reusable drill bits ($2.2M/year) and reducing computed tomography scans on lower extremity injuries ($446K/year)., Conclusion: Current medical training provides limited formal education on cost-effective care. Efforts to mitigate the growing financial and environmental costs of health care should include encouraging and incorporating resident feedback into cost reduction strategies. This tactic will likely have a positive impact on the behavior of such resident surgeons as they enter practice and have more awareness of costs and value., Level of Evidence: V (cost-minimization study)., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSOA/A496)., (Copyright © 2023 The Authors. Published by The Journal of Bone and Joint Surgery, Incorporated. All rights reserved.)

Background: Identifying ideal candidates for orthopaedic surgery residency is difficult. Data available for applicant selection are evolving; preclinical grades and the Alpha Omega Alpha (AOA) honors society are being phased out at some medical schools. Similarly, three-digit United States Medical Licensing Examination (USMLE) Step 1 scores have been eliminated. There is renewed interest in improving resident selection to provide a diverse, comprehensive educational opportunity that produces orthopaedic surgeons who are prepared for practice., Questions/purposes: We sought to identify whether (1) academic achievements, (2) letters of recommendation, (3) research activity, and (4) miscellaneous factors available on Electronic Residency Application Service (ERAS) applications were associated with outstanding residency performance., Methods: Ten faculty members (22% of all full-time faculty) with extensive educational involvement for at least 7 years, whose expertise covered all subspecialty departments at an urban, academic orthopaedic surgery residency program, were given an anonymous survey on the performance of the four most recent classes of residency graduates (24 residents). This survey was developed due to the lack of a validated residency outcomes tool or objective metrics for residency performance. The evaluated criteria were decided upon after discussion by a relatively large group of academic orthopaedic surgeons considering the factors most important for graduating orthopaedic residents. The faculty were selected based on their long-term knowledge of the residency, along with their diversity of specialty and backgrounds; there were no nonresponders. Faculty graded each resident on a scale from 1 to 10 (higher is better) on six criteria: surgical technical skills, research productivity, clinical knowledge, professionalism, personality, and fellowship match. The mean of the faculty ratings made by all faculty for all six criteria was calculated, producing the overall residency performance score. Factors available on each resident's ERAS application were then correlated with their overall residency performance score. Categorical ERAS factors, including AOA status, five or more honors in core clerkships, at least three exceptional letters of recommendation, collegiate athletics participation, expertise with a musical instrument, and research (6-year) track residents, were correlated with overall residency performance score via point biserial analysis. Continuous ERAS factors including USMLE Step 1 and Step 2 scores, number of publications before residency, number of research years before residency, medical school ranking, and number of volunteer experiences were correlated with overall residency performance score via Pearson correlation. USMLE Step 1 three-digit scores were evaluated despite their recent elimination because of their historic importance as a screening tool for residency interviews and for comparison to USMLE Step 2, which retains a three-digit score. Application factors with a p < 0.2 on univariate analysis (five or more honors in core clerkships, at least three exceptional letters of recommendation, research track residents) were included in a stepwise linear regression model with "overall residency performance score" as the outcome variable. All p values < 0.05 were considered significant., Results: The mean overall residency performance score was 7.9 ± 1.2. Applicants with at least five honors grades in core clerkships had overall residency performance scores 1.2 points greater than those of their peers (95% confidence interval (CI) 0.3 to 2.0; p = 0.01, Cohen ƒ 2 = 0.2, representing a small effect size). ERAS applications including at least three exceptional letters of recommendation were associated with a 0.9-point increase in residency performance (95% CI 0.02 to 1.7; p = 0.046, Cohen ƒ 2 = 0.1, representing a small effect size). Participation in the residency research (6-year) track was associated with a 1-point improvement in residency performance (95% CI 0.1 to 1.9; p = 0.03, Cohen ƒ 2 = 0.2, again, representing a small effect size). Together, these three factors accounted for 53% of the variance in overall residency performance score observed in this study., Conclusion: Past clinical excellence, measured by core clerkship grades and exceptional letters of recommendation, is associated with slightly improved overall orthopaedic residency performance scores. Applicants meeting both criteria who also complete a research track residency may perform substantially better in residency than their counterparts, as these three factors accounted for half of all the variance observed in the current study. Although minimum requirements are necessary, traditionally used screening factors (such as USMLE scores, AOA status, medical school rank, and number of publications) may be of less utility in identifying successful future residents than previously thought., Level of Evidence: Level III, therapeutic study., Competing Interests: Each author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request., (Copyright © 2022 by the Association of Bone and Joint Surgeons.)

Purpose: To provide further clarity regarding the management of patients with abnormal femoral version in the setting of hip arthroscopy and will discuss the definition of femoral version, the diagnostic and clinical evaluation of abnormal femoral version, and several described measurement techniques., Methods: A systematic review was conducted in literature published before August 2021 that measured femoral version and reported patient-reported outcomes measures or rates of subsequent procedures following hip arthroscopy. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed and the electronic databases, PubMed, OvidMedLine, Scopus, and Web of Science were searched. Two blinded reviews screened and evaluated data quality using the Newcastle-Ottawa Scale., Results: Eighteen studies were included with 11 studies reporting patient outcomes and 7 studies reporting rates of subsequent procedures. The most commonly used definition of femoral version was 5° to 20° of femoral anteversion. Computed tomography scan was the most commonly used imaging modality. The majority of studies (7 of 11) demonstrated that femoral version does not have an impact on patient-reported outcomes measures and is not predictive of clinically meaningful improvement scores. However, in select studies, patients with femoral retroversion were found to experience slightly inferior outcomes following hip arthroscopy for femoroacetabular impingement. While femoral retroversion may be a risk factor for subsequent procedures, 3 of 7 studies refute this claim. Although in patients with borderline hip dysplasia, excessive femoral anteversion led to greater rates of subsequent hip procedures., Conclusions: While the majority of studies show that femoral version does not have an impact on patient-reported outcomes following hip arthroscopy, those with femoral retroversion and with excessive anteversion with coexisting borderline hip dysplasia need to be educated on their increased risk of subsequent operation. Ultimately, this review suggests that clinical improvement can likely be achieved regardless of femoral version., Level of Evidence: IV; systematic review of Level I-IV studies., (Copyright © 2022 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Background: Despite technical advancement, elbow ulnar collateral ligament (UCL) reconstruction is a challenging procedure due to the limitations regarding the challenging tunnel placement and potential injury to the ulnar nerve. Furthermore, current techniques for reconstruction and repair are inferior functionally and biomechanically when compared to native UCL tissue. A modified docking technique using a single-tunnel proximal suspensory fixation may reduce complications and potentially provide a technique for UCL reconstruction that is biomechanically superior. Decreasing the number of bone tunnels decreases the number of places that bone tear through could occur. The purpose was to evaluate and compare the biomechanical performances for 2 elbow UCL reconstruction techniques: (1) standard docking technique (SD) and (2) a proximal single tunnel (PST) technique using a suspensory fixation. We hypothesized that the PST technique would be biomechanically superior to the SD technique., Methods: Twelve matched pairs of cadaveric elbows were dissected and fixed at 70 degrees for biomechanical testing. Gracilis grafts were used for a docking reconstruction and the modified reconstruction with a PST suspensory fixation. A cyclic valgus torque protocol was used to precondition specimens for either reconstruction technique and the ulnohumeral gapping was then assessed. Following gapping measurements, postsurgical specimens underwent a valgus rotation applied at a rate of 5°/s until the anterior band of the UCL failed or fracture occurred. Ultimate load to failure, stiffness, and mode of failure were recorded., Results: There were no statistical differences between the two groups. Mean rotational stiffness of the SD (2.3 ± 0.6 Nm/deg) compared to the PST (1.9 ± 0.7 Nm/deg) ( P  = .41) and mean ultimate failure torque of the SD (30.5 ± 9.2 Nm) compared to the PST (30.9 ± 8.6 Nm) ( P  = .86) were similar. There was also no statistically significant difference ( P  = .83) when comparing the native UCL ulnohumeral gapping (6.0 ± 2.0 mm) to the mean ulnohumeral gapping of the SD reconstruction (6.0 ± 1.8 mm)., Conclusions: This study compares the biomechanical strength of elbow UCL reconstructions performed using the SP technique to that of a PST technique. Among all tested parameters, including ultimate failure torque, stiffness, and ulnohumeral gapping, there were no statistically significant differences between the 2 techniques., (© 2023 The Authors.)

A humeral avulsion of the glenohumeral ligament, or HAGL, lesion is a rare yet debilitating shoulder injury, which can lead to recurrent instability, pain, and overall shoulder dysfunction. The diagnosis is often difficult, requiring both high clinical suspicion, as well as identification on magnetic resonance imaging. In patients with an anterior HAGL, repair often requires an open approach. In extremely rare circumstances, the initial traumatic event that causes a HAGL can also cause disruption of the supraspinatus and subscapularis insertions on the humeral head. We have termed this the "naked humeral head". The purpose of this technical note is to describe our preferred technique to surgically treat the naked humeral head by repairing a supraspinatus avulsion fracture, HAGL lesion, and complete subscapularis tear., (© 2022 The Authors.)

Platelet-rich plasma (PRP) is a promising therapy treatment option for multiple orthopedic conditions, which has demonstrated expanding clinical use. With increased clinical use of PRP, there has been a greater demand for point-of-care (POC) biologic devices. For this review, publicly available information provided by the device corporations, PubMed, Medline, and Embase databases were searched for studies related to POC device function. A scoping review study design was selected to explore the breadth of knowledge in the literature regarding PRP POC devices. ProofPoint Biologics demonstrated the highest laboratory platelet increase (5.2 ± 0.28-fold) and the longest processing time (49 ± 1.4 minutes). Celling demonstrated the lowest laboratory platelet increase (2.7 ± 0.8-fold), while AcCELLerated had the fastest processing time (18 ± 1.4 minutes for PurePRP® AB60 Pure (Pure Accelerated Biologics, Tequesta, FL) and 13.5 ± 2.1 minutes for AbsolutePRP® (Emcyte Corporation, Fort Myers, FL)). Celling had the lowest cost out of the various biologic devices. There is significant variability in the technical features, cost, processing time, and centrifugation parameters of the different commercially available point-of-care devices., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Jildeh et al.)

➤: Orthobiologics encompass numerous substances that are naturally found in the human body including platelet-rich plasma (PRP), isolated growth factors, and cell therapy approaches to theoretically optimize and improve the healing of cartilage, fractures, and injured muscles, tendons, and ligaments., ➤: PRP is an autologous derivative of whole blood generated by centrifugation and is perhaps the most widely used orthobiologic treatment modality. Despite a vast amount of literature on its use in osteoarthritis as well as in tendon and ligament pathology, clinical efficacy results remain mixed, partly as a result of insufficient reporting of experimental details or exact compositions of PRP formulations used., ➤: Mesenchymal stromal cells (MSCs) can be isolated from a variety of tissues, with the most common being bone marrow aspirate concentrate. Similar to PRP, clinical results in orthopaedics with MSCs have been highly variable, with the quality and concentration of MSCs being highly contingent on the site of procurement and the techniques of harvesting and preparation., ➤: Advances in novel orthobiologics, therapeutic targets, and customized orthobiologic therapy will undoubtedly continue to burgeon, with some early promising results from studies targeting fibrosis and senescence., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/G983 )., (Copyright © 2022 by The Journal of Bone and Joint Surgery, Incorporated.)

In the setting of femoroacetabular impingement, arthroscopy versus open surgery confers many advantages. However, inadequate bony resection remains a concern and is the leading cause of revision surgery. Several strategies have been described to ensure a more-complete resection during hip arthroscopy. In this current technique article, the authors describe a modified anterior portal site view called the "up-the-neck" view. This view allows for greater visualization of the femoral head-neck junction and alleviates challenges faced when assessing resection intraoperatively. The "up-the-neck" view is achieved by placing a 70° arthroscope in the anterior lateral portal and subsequently rotating the camera 90°. The head-neck junction will appear horizontally, rather than vertically, on this view, which allows for the easy identification of missed imperfections. This may reduce the need for revision surgery and future investigation is necessary to determine the reoperation rates following this technique., (© 2022 The Authors.)

Arthroscopic rotator cuff repair can be performed with the patient in the beach-chair or lateral decubitus position. Patient positioning in shoulder arthroscopy is a critical step in surgical preparation and remains a debated topic. The lateral decubitus position is a reliable, safe, and effective position in which to perform nearly all types of shoulder arthroscopic procedures. The purpose of this Technical Note is to describe our preferred technique for performing arthroscopic rotator cuff repair with the patient in the lateral decubitus position, which portends several advantages, such as improved visualization of the glenohumeral space, ergonomic positioning, a low risk of cerebral hypoperfusion, and a shorter operating time., (© 2022 The Authors.)

»: Rotator cuff tear arthropathy (RCTA) describes a pattern of glenohumeral degenerative changes following chronic rotator cuff tears that is characterized by superior humeral head migration, erosion of the greater tuberosity of the humeral head, contouring of the coracoacromial arch to create a socket for the humeral head, and eventual glenohumeral arthritis., »: Acute and chronic inflammatory changes following rotator cuff tears are thought to contribute to cartilage damage, muscle fibrosis, and fatty infiltration in the glenohumeral joint., »: In vitro animal studies targeting various inflammatory modulators, including macrophages, insulin-like growth factor-I, and transforming growth factor-beta pathways, provide promising therapeutic targets to improve healing after rotator cuff tears., »: The role of platelet-rich plasma in the treatment and prevention of RCTA has been investigated, with conflicting results., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSREV/A783)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

Context: There is currently no evidence-based consensus on how to treat a full-thickness, symptomatic articular cartilage injury of the patella, although numerous treatment options are available., Objective: To systematically evaluate the functional outcomes after operative treatment of patellar cartilage lesions. Our secondary purpose was to evaluate radiographic outcomes after treatment., Data Sources: PubMed, Cochrane, and Embase., Study Selection: Studies published between January 1, 1990 and December 31, 2018 that included patient-reported functional outcomes for patients after operative treatment of patellar chondral defects at a minimum 2-year follow-up were included., Study Design: Systematic review., Level of Evidence: Level 4., Data Extraction: MINORS (Methodological Index for Non-Randomized Studies) score, level of evidence, sample size, demographic data, follow-up data, intervention, functional outcome scores, and magnetic resonance imaging (MRI) data were collected., Results: The review identified 10 studies and 293 patients receiving cartilage restoration procedures for patellar chondral defects with extractable clinical and radiographic results and data on complications and reoperations. All treatments (autologous chondrocyte implantation [ACI], matrix-induced ACI [MACI], autologous osteochondral transplantation [AOT]) utilized in the management of patellar chondral lesions, with the exception of isolated particulated juvenile articular cartilage, demonstrated statistically significant improvements in functional outcome scores compared with preoperative measurements at a minimum of 2-year follow-up. Postoperative MRIs were obtained in 6 studies and found that regardless of treatment, moderate-to-complete infill of patellar cartilage lesions was seen in the majority of patients. While failure rates were low for the various treatment modalities, rates of reoperation were substantial, with up to 40% to 60% reoperation rate seen after ACI., Conclusion: Patients treated with ACI, MACI, and AOT all demonstrated statistically significant improvements in functional outcome scores with radiographic evidence of healing at minimum of 2-year follow-up. Evidence is insufficient to recommend one particular treatment over another.

»: Concussion is a complex pathophysiologic process that affects the brain; it is induced by biomechanical forces, with alteration in mental status with or without loss of consciousness., »: Concussion assessment tools may be broadly categorized into (1) screening tests such as the SAC (Standardized Assessment of Concussion), the BESS (Balance Error Scoring System), and the King-Devick (KD) test; (2) confirmatory tests including the SCAT (Sport Concussion Assessment Tool), the ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing), and the VOMS (Vestibular Oculomotor Screening); and (3) objective examinations such as brain network activation (BNA) analysis, imaging studies, and physiologic markers., »: The KD, child SCAT3 (cSCAT3), child ImPACT (cImPACT), and VOMS tests may be used to evaluate for concussion in the pediatric athlete., »: Future work with BNA, functional magnetic resonance imaging, diffusion tensor imaging, and serum biomarkers may provide more objective assessment of concussion, neurologic injury, and subsequent recovery., Competing Interests: Disclosure: The authors indicated that no external funding was received for any aspect of this work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSREV/A697)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

Case: Calcific tendinitis of the gluteus maximus is a rare condition with poorly described operative treatment options. We present a 51-year-old man with chronic left posterolateral hip pain because of gluteus maximus calcific tendinitis that was refractory to conservative treatment. Endoscopy was pursued given the severity and chronicity of his symptoms. The patient remains asymptomatic without recurrence., Conclusion: This is the first description of endoscopic management of calcific tendinitis of the gluteus maximus. This is a minimally invasive, efficacious option for management of this pathology., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSCC/B502)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

Objectives: A total of 30% to 40% of soft tissue sarcoma (STS) patients develop major wound complications (MWCs) after preoperative radiation (preRT). The optimal preRT-surgery interval and its association with MWCs is unknown. This study investigated whether a longer preRT-surgery interval is associated with fewer MWCs compared with historical controls., Methods: All patients treated by a single surgeon after preRT with limb-sparing wide resection for extremity and trunk STS were retrospectively reviewed from 2004 to 2014. The primary outcome was MWCs defined as a secondary operation, invasive procedure, wound packing, or readmission for wound care. Secondary outcomes of local recurrence and survival were followed and independent variables were analyzed for an association with MWCs., Results: Fifty-four patients were included with a median follow-up of 32 months and age of 61 years. The majority of tumors were deep (91%), large (median size of 11 cm), high grade (78%) and within the lower extremity (78%). The median preRT-surgery interval was 43 days and 80% of patients received surgery 35 to 49 days after radiation. MWCs were observed in 15% of patients and 88% occurred within 40 days. Predictors for MWCs on multivariate analysis were peripheral vascular disease (P=0.03), location in the medial compartment of the thigh (P=0.03), and neurovascular involvement (P=0.03)., Conclusions: This study presents a cohort of STS patients with an extended preRT-surgery interval of ~6 weeks. MWCs in this population occurred at a lower rate than historical controls. Overall these findings support the exploration of a longer interval to reduce MWCs and their associated morbidity.

Readmission within 90 days following total joint arthroplasty has become a central quality measure of reimbursement initiatives; however, the validity of readmission rates as a measure of hospital care quality and the proportion of readmissions that are preventable are unknown. The purpose of this study is to determine if readmissions within 30 and 90 days after total knee arthroplasty (TKA) were related to orthopaedic or medical etiology and identify if these readmissions were preventable. We retrospectively reviewed 1,625 elective TKAs performed between 2011 and 2014 at our institution. Readmissions within 30 and 90 days were categorized into orthopaedic and medical etiologies and an expert research panel determined if readmissions were potentially preventable based on objective criteria from national or peer-reviewed consensus guidelines. Out of the 1,625 TKAs performed during the study period, there were a total of 79 (4.8%) readmissions within 90 days of surgery, of which 17 (22%) were of orthopaedic etiology and 62 (78%) were of medical etiology. Fifty-two (66%) of the 79 readmissions occurred within 30 days, with 11 (21%) of orthopaedic and 41 (80%) of medical etiology. Only 2 of 79 (3%) readmissions within 90 days were deemed potentially preventable, and neither of them were orthopaedic in nature. Hospital readmissions after total joint arthroplasty are inevitable; however, only a small percentage (3%) of readmissions to our health care system was potentially preventable. Orthopaedic readmissions constituted a minority of the proportion of readmissions at 30 or 90 days, and none were deemed preventable., Competing Interests: None declared., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Background: Post-discharge management following operative treatment of hip fractures continues to be performed on a case-by-case basis, with no uniform guidelines dictating management. Predicting discharge to post-acute care (PAC) facilities (i.e. skilled nursing facilities and inpatient rehabilitation facilities) can assist preoperative planning and potentially decrease length of stay secondary to disposition issues. The goal of this study was to develop a nomogram using easily identified variables to preoperatively predict discharge disposition following operative treatment of hip fractures., Methods: Using the National Surgical Quality Improvement Program database, patients who underwent surgical intervention for hip fractures between 2012 and 2015 were identified. A multivariable logistic regression model was used to identify risk factors for discharge to a PAC facility, and a predictive nomogram was created based on these results., Results: From 2012 to 2015, 33,371 hip fractures were identified: 13,336 (40%) femoral neck fractures, and 20,035 (60%) intertrochanteric femur fractures. Of the patients identified, 26,082 (78.2%) were discharged to a PAC while the remainder were discharged home with or without home health. 70% of patients were female and 92.4% were Caucasian. When accounting for comorbidities, using the American Society of Anesthesiologists (ASA) classification system, 6,122 patients (18.4%) had 'Mild Systemic Disease' (ASA 2), 20,872 (62.6%) patients had 'Severe Systemic Disease' (ASA 3), and 6,006 (18.1%) had 'Life Threatening Disease' (ASA 4/5). The majority of patients were brought in from a 'Home' setting, while 10.4% of patients were admitted from a 'Long-Term Care' setting. After controlling for confounding variables, older age and increasing ASA class were predictive of an increased risk of discharge to a PAC. Diabetes, dyspnea, congestive heart failure, and chronic obstructive pulmonary disease were not associated with an increased risk of discharge to a PAC., Discussion: Discharge disposition following operative treatment of hip fractures can be reliably predicted using a nomogram with commonly identified preoperative variables., Level of Evidence: Level III, Retrospective Cohort Design, Observational Study., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020. Published by Elsevier Ltd.)

» Anterior cruciate ligament (ACL) reconstruction is a commonly performed orthopaedic procedure with numerous reconstructive graft and fixation options. Interference screws have become one of the most commonly utilized methods of securing ACL grafts such as bone-patellar tendon-bone (BPTB) autografts. » The composition of interference screws has undergone substantial evolution over the past several decades, and numerous advantages and disadvantages are associated with each design. » The composition, geometry, and insertional torque of interference screws have important implications for screw biomechanics and may ultimately influence the strength, stability of graft fixation, and biologic healing in ACL reconstruction. » This article reviews the development and biomechanical properties of interference screws while examining outcomes, complications, and gaps in knowledge that are associated with the use of femoral interference screws during BPTB ACL reconstruction.

Purpose: The primary purpose of this investigation was to systematically evaluate the literature for the current indications and outcomes of arthroscopic labral reconstruction of the hip. Our secondary purpose was to evaluate the role of arthroscopic labral reconstruction in the management of reparable labral tears., Methods: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines using a PRISMA checklist. Studies published between June 2009 and June 2018 that evaluated outcomes after arthroscopic labral reconstruction with a minimum of 1 year of follow-up were included., Results: Eleven studies met the inclusion and exclusion criteria. A total of 373 patients were identified. Of the 11 studies, 9 reported that an irreparable labrum was their indication for reconstruction, with 8 reporting that this was ultimately determined intraoperatively. Substantial variability in surgical technique, graft choice, and concurrent pathology was found. All 11 studies used at least 1 validated functional outcome metric to evaluate surgical outcomes, with all studies reporting improvement greater than the minimal clinically important difference. Donor-site pain was the most common complication, although it was reported in only 2 studies. Reported rates of revision surgery and conversion to arthroplasty were low (range, 0%-9.1% for both)., Conclusions: All 11 studies included in this systematic review reported clinically significant functional improvements after arthroscopic labral reconstruction and low rates of complications, revision surgery, and progression of arthritis, although graft types and concomitant procedures confound the results. The most common indication for reconstruction was a deficient labrum on intraoperative evaluation. The 6 studies that evaluated patient satisfaction reported favorable results, with a range of 6.73 to 8.7., Level of Evidence: Level IV, systematic review of Level III and IV studies., (Copyright © 2019 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Recipient endogenous memory CD8 T cells expressing reactivity to donor class I MHC infiltrate MHC-mismatched cardiac allografts within 24 hours after reperfusion and express effector functions mediating graft injury. The current study tested the efficacy of Very Late Antigen-4 (VLA-4) blockade to inhibit endogenous memory CD8 T cell infiltration into cardiac allografts and attenuate early posttransplant inflammation. Peritransplant anti-VLA-4 mAb given to C57BL6 (H-2 b ) recipients of AJ (H-2 a ) heart allografts completely inhibited endogenous memory CD4 and CD8 T cell infiltration with significant decrease in macrophage, but not neutrophil, infiltration into allografts subjected to either minimal or prolonged cold ischemic storage (CIS) prior to transplant, reduced intra-allograft IFN-γ-induced gene expression and prolonged survival of allografts subjected to prolonged CIS in CTLA-4Ig treated recipients. Anti-VLA-4 mAb also inhibited priming of donor-specific T cells producing IFN-γ until at least day 7 posttransplant. Peritransplant anti-VLA plus anti-CD154 mAb treatment similarly prolonged survival of allografts subjected to minimal or increased CIS prior to transplant. Overall, these data indicate that peritransplant anti-VLA-4 mAb inhibits early infiltration memory CD8 T cell infiltration into allografts with a marked reduction in early graft inflammation suggesting an effective strategy to attenuate negative effects of heterologous alloimmunity in recipients of higher risk grafts., (© 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Microalgae biorefinery is presently receiving a lot of attention as driven by its production of high value-added products. In this study, an oleaginous microalga Aurantiochytrium limacinum SR21 was cultured for docosahexaenoic acid (DHA) production using 20% (w/v) of K 2 HPO 4 -waste feedstock to replace 0.005% (w/v) of KH 2 PO 4 in the flask culture. DHA is an essential nutrient for human's brain functionalities. Collectively, the K 2 HPO 4 -waste feedstock with working concentration of 0.005% (w/v) in the cultivation prompted a higher lipid content (8.29%) and DHA production (128.81 mg.L -1 ). Moreover, natural plant pigment products containing stabilised betacyanins were utilised as natural red colourants for hard candy production. This study develops microalgal cultivation using salt-rich waste feedstock for a higher lipid and DHA content as well as application of natural colouring agents in food products., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: The purpose of this project was to compare the rates of infections, nonunions, malunions, and secondary operations in tibia fractures resultant from low energy GSWs versus those seen in open and closed tibia fractures resultant from blunt trauma. A secondary objective was to assess the utility of using the traditional Gustilo-Anderson classification system for open fractures to describe fractures secondary to low energy GSW., Methods: A retrospective review of 327 patients with tibia shaft fractures was conducted at our level I trauma center. Patients underwent a variety of interventions depending on their injury. Standard fixation techniques were utilized. Outcome measures include: mechanism of injury, rates of superficial and deep infection, nonunion, malunion, and secondary operations., Results: Deep infection after low energy GSW tibia fractures was uncommon and seen in only 2.3% of patients. Rates of infection after low energy GSWs were similar to low and high energy closed tibia fractures resultant from blunt trauma, but significantly less than that seen in open type II (25%, p < 0.05), type IIIA (19.5%, p < 0.05), and type IIIB fractures (47%, p < 0.01). There were no nonunions following GSW fractures, versus 3.7% after closed tibia fractures from blunt trauma (p = 0.2). Nonunions were more common after open fractures from blunt trauma (11%, p < 0.05) versus GSWs. Differences in infection and nonunion were associated with more secondary operations (18%, p < 0.01) in the open tibia fracture group compared with GSWs (2.3%) and closed fractures (7.9% p = 0.19)., Conclusions: While GSWs are traditionally thought of as open injuries, low energy GSW tibia fractures had a low rate of infection and no nonunions, and resulted in a reoperation rate similar to closed blunt tibia shaft fractures and significantly lower than open tibia fractures., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Study Design: Cross-sectional study., Objective: To determine whether there is an association between body mass index (BMI) and the prevalence, severity, and frequency of low back pain and identify other potential patient risk factors for the development of low back pain., Summary of Background Data: Many studies have implicated that a high BMI is a risk factor for low back pain. However, few studies have examined the association between increased BMI and the prevalence, severity, and frequency of low back pain., Methods: Data from the Osteoarthritis Initiative, a multicenter, prospective study of knee osteoarthritis, were used to conduct this study, which included 4796 patients. BMI was categorized according to the World Health Organization classification and the prevalence, severity, and frequency of low back pain were assessed. Logistic regression was performed to identify additional patient risk factors associated with low back pain., Results: The prevalence of low back pain was found to be significantly higher in patients with an elevated BMI compared to those with normal or underweight BMI and demonstrated a stepwise increase with each BMI category. Approximately 47.4% of patients with normal or underweight BMI complained of low back pain compared with 72.8% of morbidly obese patients (P < 0.0001). No association was seen between BMI and the frequency or severity of low back pain episodes. Osteoarthritis of the back and depression were patient variables found to be associated with all three measures (prevalence, severity, and frequency) of low back pain., Conclusion: Elevated BMI is strongly associated with an increased prevalence of low back pain. Depression and osteoarthritis of the back are associated with the prevalence, severity, and frequency of low back pain., Level of Evidence: 3.

Recipient endogenous memory T cells with donor reactivity pose an important barrier to successful transplantation and costimulatory blockade-induced graft tolerance. Longer ischemic storage times prior to organ transplantation increase early posttransplant inflammation and negatively impact early graft function and long-term graft outcome. Little is known about the mechanisms enhancing endogenous memory T cell activation to mediate tissue injury within the increased inflammatory environment of allografts subjected to prolonged cold ischemic storage (CIS). Endogenous memory CD4+ and CD8+ T cell activation is markedly increased within complete MHC-mismatched cardiac allografts subjected to prolonged versus minimal CIS, and the memory CD8+ T cells directly mediate CTLA-4Ig-resistant allograft rejection. Memory CD8+ T cell activation within allografts subjected to prolonged CIS requires memory CD4+ T cell stimulation of graft DCs to produce p40 homodimers, but not IL-12 p40/p35 heterodimers. Targeting p40 abrogates memory CD8+ T cell proliferation within the allografts and their ability to mediate CTLA-4Ig-resistant allograft rejection. These findings indicate a critical role for memory CD4+ T cell-graft DC interactions to increase the intensity of endogenous memory CD8+ T cell activation needed to mediate rejection of higher-risk allografts subjected to increased CIS.

In inflamed lymph nodes, Ag-specific CD4(+) and CD8(+) T cells encounter Ag-bearing dendritic cells and, together, this complex enhances the release of CCL3 and CCL4, which facilitate additional interaction with naive CD8(+) T cells. Although blocking CCL3 and CCL4 has no effect on primary CD8(+) T cell responses, it dramatically impairs the development of memory CD8(+) T cells upon Ag rechallenge. Despite the absence of detectable surface CCR5 expression on circulating native CD8(+) T cells, these data imply that naive CD8(+) T cells are capable of expressing surface CCR5 prior to cognate Ag-induced TCR signaling in inflamed lymph nodes; however, the molecular mechanisms have not been characterized to date. In this study, we show that CCR5, the receptor for CCL3 and CCL4, can be transiently upregulated on a subset of naive CD8(+) T cells and that this upregulation is dependent on direct contact with the high endothelial venule in inflamed lymph node. Binding of CD62L and CD11a on T cells to their ligands CD34 and CD54 on the high endothelial venule can be enhanced during inflammation. This enhanced binding and subsequent signaling promote the translocation of CCR5 molecules from intracellular vesicles to the surface of the CD8(+) T cell. The upregulation of CCR5 on the surface of the CD8(+) T cells increases the number of contacts with Ag-bearing dendritic cells, which ultimately results in increased CD8(+) T cell response to Ag rechallenge., (Copyright © 2016 by The American Association of Immunologists, Inc.)