Location Of Insertion Research Articles

An adaptive local maximum entropy point collocation method for linear elasticity

Point collocation methods are strong form approaches that can be applied to continuum mechanics problems and possess attractive features over weak form-based methods due to the absence of a mesh. While various adaptive strategies have been proposed to improve the accuracy of weak form-based methods, such techniques have received little attention for strong form-based methods. In this paper, combined rh-adaptivity, in which r- and h-adaptivities are adopted iteratively, is applied to the local maximum entropy point collocation method for the first time to solve linear elasticity problems. Material force residuals act as driving forces in r-adaptivity to relocate collocation points, reducing the error associated with a given point distribution. Physical equilibrium residuals are used as the error estimator in h-adaptivity to determine the insertion locations for new points, diminishing the error caused by inadequate degrees of freedom. Issues arising in mesh-based methods, such as mesh distortion and hanging nodes, are entirely absent from the proposed method. The paper introduces the approach for the first time and the study is therefore confined to 2D domains. Numerical examples are presented to demonstrate the performance of the proposed adaptive strategies, comparing convergence rates and computational costs using uniform refinement, pure r-, h- and combined rh-adaptivities.

P–003 Transposon insertion profiling by sequencing (TIPseq) identifies novel LINE–1 insertions in human sperm

Abstract Study question Do human sperm contain novel LINE–1 insertions and are they affected by paternal age? Summary answer Human sperm contain novel LINE–1 insertions. Their location or number are not affected by paternal age. What is known already LINE–1 comprises 17% of the human genome and some LINE–1s are the only autonomous retrotransposons in humans. Retrotransposons influence genomic instability and/or regulation if new retrotransposition events disrupt coding or regulatory regions in the host genome. Demethylation during germ cell development de-represses retrotransposons. Advanced paternal age is associated with genomic instability. Previously we showed that sperm LINE–1 copy number decreases with paternal age. We hypothesize that human sperm exhibit de novo retrotransposition and that sperm from older men contain increased novel LINE–1 insertions. Study design, size, duration Cross-sectional case–control study with semen samples collected between February to July 2020. Participants/materials, setting, methods Normospermic sperm samples (n = 10; 5 <35 years old and 5 ≥45 years old) obtained from consenting men undergoing IVF at NYU Fertility Center were submitted to a novel method, single cell Transposon Insertion Profiling by Sequencing (scTIPseq) to identify and map LINE–1 insertions in human sperm. TIPseqHunter, a custom bioinformatics pipeline, compared the architecture of sperm LINE–1 to known LINE–1 insertions from the European database of human specific LINE–1 (L1Hs) retrotransposon insertions in humans (euL1db). Main results and the role of chance TIPseq identified 17 novel insertions in sperm, 8 from older (≥ 45 years) and 9 in younger men (<35 years). New insertions were mainly intergenic or intronic, including AC007402 (2/10), TMEM163 (2/7), CTTNBP2NL (3/5), AC107023 (3/3), TMC2 (2/19), MacroD2 (2/6), RAB3C (3/4), LINC02664 (1/1), AC079052 (2/3) and AC017091 (4/4). One novel insertion (<35 years old) hits a known regulatory element. Only one sample (≥ 45 years old) did not exhibit any new insertion. The location or number of novel insertions did not differ by paternal age. Limitations, reasons for caution The small sample-size and use of normospermic specimens limit interpretation of paternal age effect on LINE–1. Besides, the novel insertions could be polymorphic sites that have low allele frequency and thus have not yet been described. Wider implications of the findings: This study for the first time reports novel LINE–1 insertions in human sperm, demonstrating that scTIPseq method is a feasible technique, and identifying new contributions to genetic diversity in the human germ line. Further studies are needed to evaluate the impact of these insertions on sperm function. Trial registration number Not applicable

B-AB24-02 PIEZOELECTRIC ENERGY HARVESTING FOR PACEMAKERS

Battery depletion is the leading cause of cardiac AICD pacemaker replacement. Auto-recharging via energy harvesting (EH) is a technique that could eliminate battery replacement. Piezoelectric EH converts mechanical energy into electrical energy. Research investigating EH for implantable medical devices is limited, and most approaches require additional surgery for attachment to the epicardium. To evaluate the use of piezoelectric coatings on transvenous leads and leadless pacemakers for EH without impacting the implantation procedure. In 15 in vivo porcine hearts we tested 5 piezoelectric materials and 7 device configurations. The devices were implanted into the RV and the effects of insertion location, heart rate, and RV contractility on the piezoelectric voltage output were investigated. The animals were paced at a heart rate of 80 to 140 bpm and iv dobutamine was used to increase heart contractility. Voltage outputs and power density were shown to increase with better performing piezoelectric materials and using device designs that amplified the mechanical inputs from heart contraction and relaxation. Estimate power density for the best performing device on a lead and leadless pacemaker was 10 μW/cm3 and 5 μW/cm3, respectively. We conclude that material selection and device design affect the EH capabilities of the coatings. Power densities of the devices are approaching that of typical pacemaker batteries of 25 μW/cm3. Future studies will investigate increasing outputs using a variety of approaches including multi-layer structures, mechanical amplification, and high-performance piezoelectric materials.

Effect of the Location of Strut Chordae Insertion on Computational Modeling and Biomechanical Evaluation of Mitral Valve Dynamics

The strut chordae (SC) have a unique structure and play an important role in reinforcing the tunnel-shaped configuration of the mitral valve (MV) at the inflow and outflow tracts. We investigated the effect of varying the SC insertion location on normal MV function and dynamics to better understand the complex MV structures. A virtual parametric MV model was designed to replicate a normal human MV, and a total of nine MV modes were created from combinations of apical and lateral displacements of the SC insertion location. MV function throughout the full cardiac cycle was simulated using dynamic finite element analysis for all MV models. While the leaflet stress distribution and coaptation showed similar patterns in all nine MV models, the maximum leaflet stress values increased in proportion to the width of the SC insertion locations. A narrower SC insertion location resulted in a longer coaptation length and a smaller anterior coaptation angle. The top-narrow MV model demonstrated the shortest anterior leaflet bulging distance, lower stresses across the anterior leaflet, and the lowest maximum stresses. This biomechanical evaluation strategy can help us better understand the effect of the SC insertion locations on mechanism, function, and pathophysiology of the MV.

Long-Acting Injection and Implant Preferences and Trade-Offs for HIV Prevention Among South African Male Youth.

Long-acting pre-exposure prophylaxis (LA-PrEP) formulated as implants and injections are promising prevention method strategies offering simplicity, discretion, and long dose duration. Men are important end users of LA-PrEP, and early assessment of their preferences could enhance downstream male engagement in HIV prevention. A discrete-choice experiment survey was conducted with 406 men, aged 18-24, in Cape Town, South Africa, to assess preferences for 5 LA-PrEP attributes with 2-4 pictorially-depicted levels: delivery form, duration, insertion location, soreness, and delivery facility. Latent class analysis was used to explore heterogeneity of preferences and estimate preference shares. The median age was 21 (interquartile range 19-22), and 47% were men who have sex with men. Duration was the most important product attribute. Latent class analysis identified 3 classes: "duration-dominant decision makers" (46%) were the largest class, defined by significant preference for a longer duration product. "Comprehensive decision makers" (36%) had preferences shaped equally by multiple attributes and preferred implants. "Injection-dominant decision makers" (18%) had strong preference for injections (vs. implant) and were significantly more likely to be men who have sex with men. When estimating shares for a 2-month injection in the buttocks with mild soreness (HPTN regimen) vs. a 6-month implant (to arm) with moderate soreness (current target), 95% of "injection-dominant decision makers" would choose injections, whereas 79% and 63% of "duration-dominant decision makers" and "comprehensive decision makers" would choose implant. Young South African men indicated acceptability for LA-PrEP. Preferences were shaped mainly by duration, suggesting a sizeable market for implants, and underscoring the importance of product choice. Further research into men's acceptability of LA PrEP strategies to achieve engagement in these HIV prevention tools constitutes a priority.

Automatic modelling of human musculoskeletal ligaments - Framework overview and model quality evaluation.

Accurate segmentation of connective soft tissues in medical images is very challenging, hampering the generation of geometric models for bio-mechanical computations. Alternatively, one could predict ligament insertion sites and then approximate the shapes, based on anatomical knowledge and morphological studies. In this work, we describe an integrated framework for automatic modelling of human musculoskeletal ligaments. We combine statistical shape modelling with geometric algorithms to automatically identify insertion sites, based on which geometric surface/volume meshes are created. As clinical use case, the framework has been applied to generate models of the forearm interosseous membrane. Ligament insertion sites in the statistical model were defined according to anatomical predictions following a published approach. For evaluation we compared the generated sites, as well as the ligament shapes, to data obtained from a cadaveric study, involving five forearms with 15 ligaments. Our framework permitted the creation of models approximating ligaments' shapes with good fidelity. However, we found that the statistical model trained with the state-of-the-art prediction of the insertion sites was not always reliable. Average mean square errors as well as Hausdorff distances of the meshes could increase by an order of magnitude, as compared to employing known insertion locations of the cadaveric study. Using those, an average mean square error of 0.59mm and an average Hausdorff distance of less than 7mm resulted, for all ligaments. The presented approach for automatic generation of ligament shapes from insertion points appears to be feasible but the detection of the insertion sites with a SSM is too inaccurate, thus making a patient-specific approach necessary.

News Content Completion with Location-Aware Image Selection

News, as one of the fundamental social media types, typically contains both texts and images. Image selection, which involves choosing appropriate images according to some specified contexts, is crucial for formulating good news. However, it presents two challenges: where to place images and which images to use. The difficulties associated with this where-which problem lie in the fact that news typically contains linguistically rich text that delivers complex information and more than one image. In this paper, we propose a novel end-to-end two-stage framework to address these issues comprehensively. In the first stage, we identify key information in news by using location embeddings, which represent the local contextual information of each candidate location for image insertion. Then, in the second stage, we thoroughly examine the candidate images and select the most context-related ones to insert into each location identified in the first stage. We also introduce three insertion strategies to formulate different scenarios influencing the image selection procedure. Extensive experiments demonstrate the consistent superiority of the proposed framework in image selection.

Whole-genome resequencing using next-generation and Nanopore sequencing for molecular characterization of T-DNA integration in transgenic poplar 741

BackgroundThe molecular characterization information of T-DNA integration is not only required by public risk assessors and regulators, but is also closely related to the expression of exogenous and endogenous genes. At present, with the development of sequencing technology, whole-genome resequencing has become an attractive approach to identify unknown genetically modified events and characterise T-DNA integration events.ResultsIn this study, we performed genome resequencing of Pb29, a transgenic high-resistance poplar 741 line that has been commercialized, using next-generation and Nanopore sequencing. The results revealed that there are two T-DNA insertion sites, located at 9,283,905–9,283,937 bp on chromosome 3 (Chr03) and 10,868,777–10,868,803 bp on Chr10. The accuracy of the T-DNA insertion locations and directions was verified using polymerase chain reaction amplification. Through sequence alignment, different degrees of base deletions were detected on the T-DNA left and right border sequences, and in the flanking sequences of the insertion sites. An unknown fragment was inserted between the Chr03 insertion site and the right flanking sequence, but the Pb29 genome did not undergo chromosomal rearrangement. It is worth noting that we did not detect the API gene in the Pb29 genome, indicating that Pb29 is a transgenic line containing only the BtCry1AC gene. On Chr03, the insertion of T-DNA disrupted a gene encoding TAF12 protein, but the transcriptional abundance of this gene did not change significantly in the leaves of Pb29. Additionally, except for the gene located closest to the T-DNA integration site, the expression levels of four other neighboring genes did not change significantly in the leaves of Pb29.ConclusionsThis study provides molecular characterization information of T-DNA integration in transgenic poplar 741 line Pb29, which contribute to safety supervision and further extensive commercial planting of transgenic poplar 741.

SIns: A Novel Insertion Detection Approach Based on Soft-Clipped Reads.

As a common type of structural variation, an insertion refers to the addition of a DNA sequence into an individual genome and is usually associated with some inherited diseases. In recent years, many methods have been proposed for detecting insertions. However, the accurate calling of insertions is also a challenging task. In this study, we propose a novel insertion detection approach based on soft-clipped reads, which is called SIns. First, based on the alignments between paired reads and the reference genome, SIns extracts breakpoints from soft-clipped reads and determines insertion locations. The insert size information about paired reads is then further clustered to determine the genotype, and SIns subsequently adopts Minia to assemble the insertion sequences. Experimental results show that SIns can achieve better performance than other methods in terms of the F-score value for simulated and true datasets.

Integration of service pipes into the lower port for the DEMO Double Null Concept Design Study

A study into the viability of a double null concept for DEMO has been undertaken as part of the work to address Key Design Integration Issues within the DEMO powerplant. The objective of this study was to evaluate the feasibility of a double null architecture featuring split blanket segments to enable a wider range of maintenance options.One of the main challenges found was the integration of the service pipes to provide connections to the cooling and tritium breeding systems for the divertor and breeding blanket. By understanding how these pipes might be integrated, the constraints on key details such as the length of the lower port could be understood. This allowed for progression of other areas of the design and investigations into the remote handling of these pipes during maintenance periods.The key requirements identified for the service pipe routing included determining the removal sequence for the blanket and divertor segments during maintenance; access for the cutting and welding tool at the pipe/blanket interface; pipes grouped as modules per component; and optimisation of port space for the vacuum pumps.Two proposals were considered to investigate their impact on the insertion location for the cutting and welding tool: pipes with large radii, and pipes with smaller radii. The former was found to be preferable due to the remote maintenance advantages, versus the limited space gains offered by the latter. This paper will describe the development of these requirements, both proposals, and discuss the challenges uncovered during the study in more detail.

643 The Latest Rendition of the Ring Neck Collar Formally Known as “Watusi”

Abstract Introduction The “Watusi” neck collar originally described by Koenig has gone through a few renditions since it was introduced in 1976. Our facility adopted its use as described by Nosanov et. al, but have since made modifications to the construction that have improved positioning of the neck, patient comfort, and tolerance. Methods We used the construction design of the “Watusi” collar as described by Nosanov et. al. in 2017 • Measure patients neck length and circumference • Cut 3/8” plastic tubing • Cut a strip of 2”loop Velcro and sew a piece of hook Velcro to the underside of the loop Velcro for adhesive closure • Cut horizontal strips along the remaining loop Velcro and thread plastic tubing through Here we divert from the previously published design: • Cut ~ 8” piece of betapile and thread Velcro through (this is to pad the back of the neck). • Using 1 1/8” and 7/8” cylindrical foam tubes, cut a slit along the length of cylindrical foam to allow for insertion of the plastic tubes. This allows for ease of application and removal for hygiene/cleaning. • Lay the betapile pad on the posterior neck and apply the rings w/ cylindrical foam inserts (using clinical judgement regarding number and location of foam inserts until optimal neck position is achieved). Results We have used this method on 15 patients since 2017 and have found improved neck extension with use of foam inserts as well as pressure along cervicomental region (see attached photos). It continues to allow for some neck movement while applying targeted pressure over anterior/lateral neck bands. The removable foam inserts make cleaning easier compared to earlier versions. The application process of our modified ring neck collar is not as straight forward as alternative neck positioning devices and staff require additional training on proper application and management, however we find that when applied with adequate tension, the ring neck collar provides excellent targeted pressure to the cervicomental region as well as lateral neck bands to reduce banding and soft tissue contractures. Many patients report improved comfort with use of ring neck collar when compared to hard orthoplast anterior neck conformers and the associated risk of pressure injury is less than that of a hard neck conformer. Conclusions The modified ring neck collar can provide targeted pressure to soft tissue bands of the neck and should be considered as a tool to use to reduce risk of soft tissue neck contractures. Our facility will continue to utilize this device as well as seek ways to improve the design and patient tolerance.

The Risk Factors of Phlebitis in The Installation of Intravent Catalysts

Background: A hospital is a health service facility that allows nosocomial infections, namely phlebitis. Phlebitis is a complication of intravenous catheter placement that is characterized by redness, pain, swelling, and fever. The high rate of phlebitis in various countries is due to the risk factors that predispose to the incidence of phlebitis due to intravenous catheter placement.Objective: This study aims to determine the risk factors for phlebitis in intravenous catheter placement.Methodology: This study uses an observational analytic method with a cohort design. The study was conducted on 27 February - 14 March 2020 with 22 samples taken using purposive accidental sampling in the inward and RST surgery Dr. Soedjono Magelang. The instrument used was an observation sheet designed by researchers that had been tested by experts and a standard operational checklist for infusion. Data analysis uses a chi-square test and multiple logistic regression.Results: The incidence of phlebitis was 7 respondents (31.8%) and the associated risk factors were the type of infusion fluid (RR = 4.37 CI 95% 1.09-17.58; p-value 0.020). While the factors of age, sex, nutritional status, chronic diseases, types of injection drugs, insertion location, duration of installation, nurse skills, installation techniques, and catheter size were not related to the incidence of phlebitis (p-value 0.05).Conclusion: Although several factors are not related to the incidence of phlebitis, these factors can be a support for the incidence of phlebitis.

CRISPRbuilder-TB: "CRISPR-builder for tuberculosis". Exhaustive reconstruction of the CRISPR locus in mycobacterium tuberculosis complex using SRA.

Mycobacterium tuberculosis complex (MTC) CRISPR locus diversity has long been studied solely investigating the presence/absence of a known set of spacers. Unveiling the genetic mechanisms of its evolution requires a more exhaustive reconstruction in a large amount of representative strains. In this article, we point out and resolve, with a new pipeline, the problem of CRISPR reconstruction based directly on short read sequences in M. tuberculosis. We first show that the process we set up, that we coin as "CRISPRbuilder-TB" (https://github.com/cguyeux/CRISPRbuilder-TB), allows an efficient reconstruction of simulated or real CRISPRs, even when including complex evolutionary steps like the insertions of mobile elements. Compared to more generalist tools, the whole process is much more precise and robust, and requires only minimal manual investigation. Second, we show that more than 1/3 of the currently complete genomes available for this complex in the public databases contain largely erroneous CRISPR loci. Third, we highlight how both the classical experimental in vitro approach and the basic in silico spoligotyping provided by existing analytic tools miss a whole diversity of this locus in MTC, by not capturing duplications, spacer and direct repeats variants, and IS6110 insertion locations. This description is extended in a second article that describes MTC-CRISPR diversity and suggests general rules for its evolution. This work opens perspectives for an in-depth exploration of M. tuberculosis CRISPR loci diversity and of mechanisms involved in its evolution and its functionality, as well as its adaptation to other CRISPR locus-harboring bacterial species.

Text Analysis-Based Watermarking Approach for Tampering Detection of English Text

Due to the rapid increase in the exchange of text information via internet networks, the security and the reliability of digital content have become a major research issue. The main challenges faced by researchers are authentication, integrity verification, and tampering detection of the digital contents. In this paper, text zero-watermarking and text feature-based approach is proposed to improve the tampering detection accuracy of English text contents. The proposed approach embeds and detects the watermark logically without altering the original English text document. Based on hidden Markov model (HMM), the fourth level order of the word mechanism is used to analyze the contents of the given English text to find the interrelationship between the contexts. The extracted features are used as watermark information and integrated with digital zero-watermarking techniques. To detect eventual tampering, the proposed approach has been implemented and validated with attacked English text. Experiments were performed using four standard datasets of varying lengths under multiple random locations of insertion, reorder, and deletion attacks. The experimental and simulation results prove the tampering detection accuracy of our method against all kinds of tampering attacks. Comparison results show that our proposed approach outperforms all the other baseline approaches in terms of tampering detection accuracy.

Entropy-Based Watermarking Approach for Sensitive Tamper Detection of Arabic Text

The digital text media is the most common media transferred via the internet for various purposes and is very sensitive to transfer online with the possibility to be tampered illegally by the tampering attacks. Therefore, improving the security and authenticity of the text when it is transferred via the internet has become one of the most difficult challenges that researchers face today. Arabic text is more sensitive than other languages due to Harakat’s existence in Arabic diacritics such as Kasra, and Damma in which making basic changes such as modifying diacritic arrangements can lead to change the text meaning. In this paper, an intelligent hybrid solution is proposed with highly sensitive detection for any tampering on Arabic text exchanged via the internet. Natural language processing, entropy, and watermarking techniques have been integrated into this method to improve the security and reliability of Arabic text without limitations in text nature or size, and type or volumes of tampering attack. The proposed scheme is implemented, simulated, and validated using four standard Arabic datasets of varying lengths under multiple random locations of insertion, reorder, and deletion attacks. The experimental and simulation results prove the accuracy of tampering detection of the proposed scheme against all kinds of tampering attacks. Comparison results show that the proposed approach outperforms all of the other baseline approaches in terms of tampering detection accuracy.

A Data Encryption and Approximate Recovery Strategy Based on Double Random Sorting and CGAN

The measurement data in the power system may be attacked and tampered during the transmission. For this problem, a data encryption and approximate recovery strategy based on double random sorting and CGAN is proposed. The double random sorting encryption algorithm is proposed based on the form of measurement data in plaintext. The randomness of pseudo-random number, random sequence and random sequence insertion will ensure the uncertainty of data block number, sorting order and insertion location of random sequence, which will definitely improve the security of measurement data. Besides, an approximate recovery strategy used to approximately recovery abnormal samples is proposed on the base of CGAN, which can ensure the accuracy of decryption. Finally, the feasibility, and effectiveness of the proposed method are analyzed on wind power and photovoltaic power historical dataset.

The City in Flux: Toward an Urban Topology of Hong Kong Cinema

Whether appearing as a dramatic setting or as a “protagonist” in itself, Hong Kong’s urban space has inspired the imagination of filmmakers of different generations and artistic orientations. If architecture is the primary denominator of a city’s spatial identity,1 the cinema offers a repertoire of visual vocabularies through which this identity is articulated, contested, and transformed in time. “Space” here connotes both the diegetic configuration of setting and locale, and the non-diegetic realm of identity-making invoked by the cinematic medium. Space has also been used as a conceptual tool in critical discourse on the dynamics between the cinematic imagination and the urban space.2 Its long tradition of martial arts films and costume dramas notwithstanding, Hong Kong cinema displays an inherently urban quality that speaks through its subject matter, fictional personae, and the spatial aesthetics that have become an imprint of “Hong Kong-made films.” While critical attention to the relationship between the cinema and urban space tends to favor popular action films from the 1980s and afterward, filmmakers’ self-conscious engagement with the urban space can be traced further back. The black-and-white films of the 1950s and 1960s, for instance, frequently insert location shots at the beginning to authenticate the predominantly studio setting. The most commonly used scenes are panoramic views of high-rise buildings, motorways, rail stations, and different types of modern transportation. Mostly appearing in the credit sequence, these shots display an inner logic that amounts to a self-narrative of the city that varies from a critical self-distancing from the capitalist city in left-wing films to a celebratory embrace of capitalist modernity in right-wing films.3 The symbolic reinvention of the urban space as an experiential realm of identity-making, therefore, has been a leitmotif in Hong Kong films for a much longer time than it is commonly assumed.

Çocuk Hastalarda Tünelli Santral Venöz Kateterlerin Perkütan ve Cerrahi Yerleştirilmesindeki Komplikasyonlar

Objective: Percutaneous insertion of permanent tunneled catheters, accompanied by ultrasonography (USG) guidance, has established itself as practical, safe, and widely used procedure. The purpose of our study; To examine and compare the complications associated with permanent tunneled catheters placed by percutaneous or open surgical method in pediatric hemato-oncology patients. Methods: Medical records of 101 pediatric patients from the ASA 3-4 group who were placed in a Hickman-type tunneled central venous catheter for bone marrow transplantation between 2013 and 2015 in our clinic were retrospectively reviewed. Demographic data of the patients, catheter insertion location, size, complications encountered during and after the intervention, and reasons for catheter removal were recorded. Results: One hundred and one tunneled central venous catheters were placed percutaneously under USG guidance in 54 patients, and using open technique in 47 patients. Patients in both groups were similar in terms of age, height, weight, size of the inserted catheter, duration of catheterization, and reasons for removal. No difference was found between percutaneous and surgical groups in terms of intraoperative and postoperative to technique, and infective complications related to catheter. Conclusion: In pediatric hemato-oncology patients, there is no difference in terms of intraoperative, and postoperative complications between percutaneous technique and open technique for permanent tunneled central catheter insertion. Both techniques can be used with low complication rates, and the percutaneous technique may be preferred because it is less invasive.

Serial Changes in Perianchor Cysts Following Arthroscopic Labral Repair Using All-Suture Anchors.

BackgroudChanges in perianchor cysts around the all-suture anchors, which demonstrate distinguished features from the biocomposite anchors, have not been revealed sufficiently. The purpose of this study was to investigate serial changes of perianchor cysts according to the location of the inserted anchor in the glenoid in arthroscopic labral repair using all-suture anchors.MethodsWe enrolled 43 patients who underwent computed tomography (CT) immediately postoperatively and CT arthrogram (CTA) at 1 year or 2 years after arthroscopic labral repair using a 1.3-mm all-suture anchor for recurrent anterior shoulder dislocation with or without a superior labral tear from anterior to posterior and a posterior labral tear. The mean diameter and tissue density (HU) of perianchor cysts were measured depending on the location in the glenoid. Clinical outcomes, labral healing, and redislocation rate were evaluated at 2 years after surgery.ResultsOn functional assessment, the mean American Shoulder and Elbow Surgeons score and Rowe score improved statistically significantly after surgery (from 47.9 ± 14.3 preoperatively to 90.1 ± 9.6 postoperatively and from 45.3 ± 12.4 preoperatively to 92.2 ± 10.1 postoperatively, respectively; p < 0.01). Postoperative redislocations were found in 2 patients (4.7%). In radiological evaluation, the mean diameter of perianchor cysts at postoperative 1 year (3.24 ± 0.65 mm) was significantly larger than the immediate postoperative diameter; however, there was no significant difference between postoperative 1 year and 2 years (3.23 ± 0.57 mm). Tissue density at the center of cysts demonstrated no significant difference between 1 and 2 year postoperatively (107.7 ± 29.8 HU [superior], 99.7 ± 31.7 HU [anteroinferior], and 105.1 ± 25.0 HU [posterior] vs. 109.1 ± 26.1 HU [superior], 106.4 ± 30.3 HU [anteroinferior], and 111.0 ± 32.9 HU [posterior]). The mean diameter of perianchor cysts in the anteroinferior position was largest compared with that in superior or posterior positions.ConclusionsPerianchor cysts associated with all-suture anchors enlarged significantly within 1 year after arthroscopic labral repair regardless of the insertion location in the glenoid. However, the size and tissue density of perianchor cysts were similar at postoperative 1 and 2 years, and satisfactory stability and clinical outcomes were obtained.

Latissimus dorsi tendon transfer in reverse shoulder arthroplasty: transfer location affects strength.

BackgroundThe optimal insertion location of a latissimus dorsi tendon transfer to restore external rotation after reverse shoulder arthroplasty (RSA) is not well established. The aim of this biomechanical study was to determine the effect of tendon transfer location on external rotation torque, in conjunction with varying RSA humeral component lateralization. We hypothesized that proximal tendon transfers, along with increasing humeral lateralization, would maximize external rotation torque.MethodsEight fresh-frozen cadaveric shoulders underwent RSA and were tested on an in vitro shoulder simulator. A latissimus dorsi tendon transfer was tested at three insertion locations (lateral greater tuberosity [Lat-GT]; teres minor footprint [Tm-FP]; lateral shaft [Lat-Shft]), and external rotation torque was measured. Additional test conditions included varying humeral component lateralization (-5, 0, +5, +10, +15 mm), abduction angle (0°, 45°, 90°), and internal/external rotation (-60°, -30°, 0°, 30°, 60°).ResultsThe Lat-GT and Tm-FP insertions of the latissimus dorsi transfer both generated significantly greater torques (P < .001) than the Lat-Shft. When comparing Lat-GT to Tm-FP, there were no significant differences (P = .362). At 60˚ of external rotation, RSA humeral component lateralization from -5 to +15 mm significantly increased the external rotation torque of Lat-GT by 67% (P = .035), Tm-FP by 43% (P = .001), and of Lat-Shft by 42% (P = .002).ConclusionLatissimus dorsi tendon transfer to the proximal lateral aspect of the greater tuberosity and to the insertion site of the teres minor generated significantly more external rotation torque than transfer to the lateral humeral shaft. In addition, the use of a humeral component with greater offset also substantially increases the torque generated by the tendon transfer.