Position Of Block Research Articles

COMPARISON OF INDEPENDENT SPIKE DRILLING TRAINING AND WITH A SETTER ON IMPROVING 3-METER SPIKES FOR VOLLEYBALL ATHLETES 17-19 YEARS OLD

The purpose of this study was to determine the effect of two forms of training that is with the drilling spike method independently with gradual distance and drilling spike with setter with Spiker Specialization attribute variables on the ability to spike 3 meters. The method used in this research is an experiment with the treatment by level 2 x 2 design. This research was conducted within the scope of the DKI Jakarta Volleyball Pengprov with a population of XX PON Pelatda athletes in DKI Jakarta Province who experienced chronic ankle sprain totaling 76 athletes with a composition of 42 athletes in the position of Outside Hitter and 34 athletes in the position of Middle Block. The sample in this study amounted to 44 people with purposive proportional random sampling technique then divided into 4 groups. The instrument used to measure 3-meter spikes in this study is the Spike Skills Test instrument. Based on the results of data processing and analysis, it can be concluded that: (1) There is a difference between drilling spike training therapy independently with gradual distance and drilling spike with setter to increase 3-meter spike, (2) There is an interaction between training therapy and spiker specialization to increase 3-meter spike, (3) There is a difference between drilling spike training independently with gradual distance to increase 3-meter spike in the group of athletes who position as Outside Hitter, 3-meter spike improvement is higher if trained spike drilling independently, (4) There is a difference between independent spike drilling training with gradual distance on 3-meter spike improvement in the group of athletes positioned as Middle Blocker, 3-meter spike improvement is higher if trained spike drilling with a setter.

Arthroscopic Eden-Hybinette procedure with Triple-Pulley and four point anti-rotation fixation technique for recurrent anterior dislocation of shoulder joint

To explore effectiveness of arthroscopic Eden-Hybinette procedure with Triple-Pulley and four point anti-rotation fixation technique in the treatment of recurrent anterior dislocation of shoulder joint. A clinical data of 14 patients with recurrent anterior dislocation of shoulder joint and glenoid bone defect, who were met the selective criteria and admitted between February 2021 and February 2022, was retrospectively analyzed. All patients were treated with arthroscopic Eden-Hybinette procedure and the bone blocks were fixed by using Triple-Pulley and four point anti-rotation fixation technique. There were 9 males and 5 females with an average age of 31.2 years (range, 22-40 years). Shoulder dislocation occurred 4-10 times (mean, 6.8 times). The time from the initial dislocation to the admission was 1-6 years (mean, 3.3 years). The Instability Severity Index Score (ISIS) was 7.2±0.8, the Beighton score was 2.9±2.4, and the width ratio of glenoid bone defect was 26.64%±1.86%. Pre- and post-operative visual analogue scale (VAS) score, the University of Califonia-Los Angeles (UCLA) shoulder score, Constant score, and American Association of Shoulder and Elbow Surgeons (ASES) score were used to evaluate shoulder pain and function. The position, healing, resorption, and remodeling (glenoid area) of the bone blocks were evaluated by CT of shoulder joint. All patients underwent surgery successfully without any serious complications. All patients were followed up 11.5-13.8 months (mean, 12.0 months). The VAS scores of shoulder joint after operation decreased compared to preoperative levels, while the UCLA score, Constant score, and ASES score all increased, with significant differences ( P<0.05). And with the prolongation of time, the above indicators further improved, and the differences between different time points were significant ( P<0.05). Imaging reexamination showed that the bone block completely filled the glenoid defect, with good position and no significant displacement. Over time, the bone block healed and partially absorbed and remodelled. The postoperative glenoid area increased significantly compared to preoperative area ( P<0.05). With the prolongation of time, the glenoid area significantly decreased, but the difference was not significant between different time points ( P>0.05). For the recurrent anterior dislocation of shoulder joint, Triple-Pulley and four point anti-rotation fixation technique in Eden-Hybinette procedure can effectively prevent bone rotation, make fixation more reliable, and easy to operate and achieve good effectiveness.

Ultra-fine quantitative removal of silicon materials by femtosecond laser

The development of miniaturized electronic devices is highly dependent on precision manufacturing techniques. To achieve device miniaturization, material removal and processing accuracy down to the submicrometer or even nanometer level are required. The precision machining of the mass block, a key component of the silicon micro-gyroscope, is taken as a reference. To achieve the precision positioning function of the micro-gyroscope, the mass at a certain position of the Si-based mass block must be precisely controlled. Therefore, the ultra-fine quantitative removal process of silicon materials is studied. A femtosecond laser processing system is constructed, and the evolution of micro–nanostructure and etching depth on the silicon surface is explored. An ultra-fine quantitative removal process is developed to achieve quantitative removal of different etching depths on the silicon surface. The experimental results show that the minimum removal thickness can be 0.502 µm. The processing index requirement for a silicon surface removal thickness of less than 0.001 mm has been fulfilled. It is critical to resolve the issue of high-quality manufacturing of miniaturized silicon-based devices.

Performance Comparison of Vertex Block Descent and Position Based Dynamics Algorithms Using Cloth Simulation in Unity

This paper presents a comparative study of the Vertex Block Descent (VBD) and Position-Based Dynamics (PBD) algorithms, focusing on their performance in physical simulation tasks. Unity, a versatile physics engine, served as the simulation platform for the experiments. Among various types of physical simulations of deformable objects, fluids, and cloth dynamics, cloth simulations were chosen for implementation with both algorithms. The experimental setup ensured identical parameters, including time steps and movement behavior, for both algorithms across scenarios involving hanging, object-to-object collisions, and self-collisions. The results indicate that while the performance difference in frames per second (fps) between the two algorithms is negligible for simulations with a small number of nodes, the VBD algorithm consistently outperforms the PBD algorithm as the node count increases. Furthermore, this study provides practical guidelines for maintaining real-time performance, detailing the maximum node count each algorithm can support, while sustaining a minimum threshold of 30 fps, which is necessary for real-time applications. The comparison was conducted using CPU-based computation to establish a baseline for future studies in GPU-accelerated environments, where parallel processing is expected to further highlight the performance advantages of VBD. Future work will extend this research by evaluating additional physical simulation models, including the Mass-Spring System and Extended Position-Based Dynamics (XPBD), and developing optimizations to enhance the efficiency and scalability of these algorithms.

Theoretical Analysis of Shaft Wall Damage and Failure Under Impacting of Ore-Rock Falling in Vertical Ore Pass

The impact of ore-rock blocks on the shaft wall of a vertical ore pass is a crucial cause of shaft wall damage and failure. Based on the structure and parameters of the ore pass in a case mine, the first collision’s position of the ore-rock block with respect to the ore pass wall and the angle between the impacting direction of the ore-rock block and the horizontal plane before and after the collision are investigated via a kinematic analysis. The normal and tangential analysis models of ore rock impacting the shaft wall are established and analyzed based on contact mechanics. The results show that: (1) based on the kinematic analysis of ore rock moving in the ore pass and on the colliding condition of the ore-rock block the first time that it collides with the ore pass wall, the coordinates and angles of the collision are proposed; (2) the impacting process of ore rock is categorized into elastic compression, elastic–plastic compression, and rebound of the shaft wall material. The relationship between the normal impact force and the penetrating depth is determined, and the slipping distance of the ore-rock block along the shaft wall and the lost volume of the shaft material are established. (3) The wall material’s normal, tangential, and total restitution coefficient is acquired. (4) The total lost volume during the collision is obtained through the analysis and solution of the model. (5) Based on the characteristics and parameters of the ore pass in the case mine, the influence of the impact velocity and angle of the ore-rock block on the restitution coefficient, maximum normal intrusion depth, maximum tangential displacement, and volume loss of the shaft wall are analyzed by using relevant formulas.

Stochastic stability of random stacking of blocks

The paper explores the stability of a tower obtained by stacking identical rectangular blocks on top of each other with an inherent randomness due to slight positional offsets between successive blocks. With probabilistic modeling techniques, the diffusive behavior of the stacking process is studied and the collapse is seen as a first passage time problem. In the considered model, alignment errors are idealized as independent Gaussian random variables with zero mean and given standard deviation. We derive expressions for the joint probability density functions of block positions, and analyze their correlation. The study extends to the stochastic stability of a stack of given height, by exploring the statistical characteristics of the center of gravity of the part of tower above each block. Eventually, the probabilistic analysis of collapse is developed to quantify the statistics of the number of blocks that can be heaped up before the tower topples. Although this problem may initially appear playful, it offers an illustrated introduction to first passage problems on a non homogenous process. From a practical standpoint, this analysis offers a simple understanding of the influence of alignment errors on the overall stability of a stack, which may find several fields of application.

Conceptual design study of the tritium breeding unit for verifying the long-term performance of the breeding blanket

Fusion reactors produce high-energy neutrons through the Deuterium-Tritium (DT) reaction. The long-term performance verification and structural integrity assessment of the breeding blanket under continuous plasma operation are essential for the development of Demonstration fusion power reactor (DEMO) breeding blankets. The Korea Institute of Fusion Energy (KFE) has been planning the construction of a test facility called the Integrated Breeding Test Facility (IBTF) that uses a linear accelerator as the neutron source. A solid beryllium target has been considered to generate fusion-like neutrons. A conceptual design of the Tritium Breeding Unit (TBU), which is a key component of the breeding blanket, has been carried out. This study evaluated tritium production under fusion-like conditions using factors such as the position and thickness of the graphite block, the thickness of the first wall, and the radial length of the breeding zone. The results showed that increasing graphite block thickness and optimizing the dimensions of the TBU enhanced tritium production. However, these changes affected the structural integrity of the TBU. The side wall of the TBU experienced membrane plus bending stress, which exceeded the Level C and D acceptance criteria under the assumption of In-Box LOCA. Measures were investigated to ensure structural integrity while improving tritium production of the TBU.

A Specific Test of Starting Blocks: Intrasession and Intersession Reliability of Isometric Strength Using a Functional Electromechanical Dynamometer

Aims: To determine the intrasession and intersession reliability of the isometric force at three different starting block positions, to compare the intrasession and intersession reliability of the peak and average isometric force of three different starting block positions, and to compare the intrasession and intersession reliability of three different starting block positions. Methods: Eighteen male college students participated in this study. A repeated measures design was used to evaluate the intrasession and intersession reliability of isometric force in three different starting block positions. Results: Very high and extremely high reliability of the average and peak isometric force of the three positions of the starting blocks were obtained, with ICC ranging from 0.63 to 0.91 and a CV close to 10%. Peak force was able to determine the outcomes of the bilateral position with higher reliability than the mean force, and the dominant was the most reliable position for assessing the starting blocks. Conclusion: The functional electromechanical dynamometer can be used with a high level of reliability to assess the force exerted in the starting blocks.

Seismic characteristics of segmental tunnels considering seal roof blocks arrangement

The position of seal roof block may greatly affect the overall performance of the segmental tunnel. However, a few investigations have been dedicated to evaluating this effect. In the present study, finite element models are established to simulate the ring structure-soil model in order to evaluate the capacity curve of the universal ring structure during progressive failure. Nineteen universal ring structures configurations were analyzed considering different locations of the adjacent seal roof blocks. The models accurately simulated the structural details of the typical handhole for curved bolt in the circumferential and longitudinal joints. The seismic performance of the universal ring structure with different configurations is evaluated and discussed in terms of the moment curve, plastic zone distribution, joint opening angle curve and capacity curve of the universal ring. The results indicate that there are significant differences in the maximum positive and negative moment, plastic zone, and tensile angle of the universal ring structure when the seal roof block is in different positions. At the same time, the development of the performance curve of the ring will also show significant differences, especially in the elastic stage. The structure exhibits best seismic performance when the seal roof block is located at arch shoulder and waist (−67.5° ± 22.5°) because it is less likely to reach the normal function, immediate operational, rectifiable or irreparable damage stages compared to other configurations.

Investigations of sequential excavation and reinforcement in tunnels based on the extended three-dimensional discontinuous deformation analysis method

The unloading effect of excavation is the key factor leading to rock mass instability, and bolt support is the key means of controlling the stability. However, the original three-dimensional discontinuous deformation analysis method (3D DDA) can only simulate rock mass instability and bolt support after the tunnel is excavated, which makes it difficult to study the effect of tunnel excavation and bolt support on rock mass stability. Therefore, an algorithm to confirm the excavated blocks and reinforced blocks based on the volume judgment method (VJM) was proposed in this paper. Sequential excavation and reinforcement in tunnels can be simulated by introducing the time variables of block excavation and bolt deployment into the 3D DDA method. By embedding these two algorithms in the 3D DDA method, an extended 3D DDA method for sequential excavation and reinforcement in tunnels was developed, named the 3D DDA_ES method. Based on the 3D DDA_ES method, the collapse that occurred during the construction of the Huangjiazhuang Tunnel was simulated, and the displacement of key blocks and the axial force of the bolts were analyzed. According to the simulation results, the axial force on the bolts is strongly related to the position of the key blocks, and the axial force on the bolts at the tunnel roof is much greater than that at the tunnel arch shoulder. In this regard, these bolts with axial forces less than 1 kN are removed during the simulation, and the key blocks remain stable with a maximum displacement of 12 cm. The research results can provide a theoretical basis for tunnel construction and reinforcement parameter optimization for similar projects.

Study on Stress Characteristics Response of Submarine Shield Segment Under Ultra-high Water Pressure

In the construction and operation stage of shield tunnel, mastering and clarifying the mechanical characteristics of the overall structure is essential for ensuring shield tunnel safety. In this paper, the shell-spring model is established by ABAQUS finite element software for the ultra-high water pressure submarine shield tunnel. The mechanical behavior of shield segment structure under varying water pressure, different key block position and different strata is studied and analyzed. The results show that at the same segment assembly position, the axial force of the segment increases greatly with the increase of water pressure, and the growth rate is as high as 150 %. The internal force of the segment is mainly axial force. Under the ultra-high water pressure, the corresponding position of the maximum deformation of the segment is related to the position of the segment joint at the arch bottom. In the staggered assembly, the axial force fluctuation near the arch bottom is larger than that of the straight assembly, and the peak bending moment and the maximum axial force are near the invert. In addition, near the 120 degree of the vault, the bending moment oscillates obviously near the joint in the stratum with small coefficient of soil reaction. The larger the coefficient of soil reaction is, the more uniform the axial force of the whole segment is. The research results provide a theoretical insights for the optimization design of shield tunnel segments.

The progressive failure features of shield tunnel lining with large section

Investigating the failure process of segmental lining is of great significance to the design and maintenance of shield tunnel. Indoor scaled model tests are carried out to study the inner force, structural displacement, acoustic emission signals and damage pattern of lining. Meanwhile, a new numerical approach is put forward based on particle element method to study the influence of geo-stress field and the position of void or key block to the failure features of lining. The results showed that the failure of lining is progressive and can be divided into four stages, that is, the initial elastic stage, meso-damage stage, macroscopic failure stage and overall instability stage. For the key block is located at the crown, there are two concentrated intervals for the generation of micro-cracks. For the key block is located on the spandrel, micro-cracks are uniformly produced throughout the loading process after the initial elastic stage. For the key block is located on the haunch, micro-cracks distributed in a large concentrated range. The influence of the position of void on the damage of lining can be divided into three kinds, namely, no effect; affecting the emerging order of cracks while not final fracture pattern; affecting the emerging order of cracks and the final fracture pattern.

Tailoring Silk Sericin Grafting: Comparing One‐Step and Two‐Step Approaches for PNIPAM/PAMPS Block Nanoparticles

AbstractStructurally defined, protein‐grafted nanoparticles are widely used in various biomedical applications, particularly as intelligent nanocarriers for drug delivery. The integration of synthetic polymers with natural proteins such as silk sericin enhances the functionality and stability of these nanocarriers, making them suitable for targeted and controlled drug release. In this context, an optimized grafting procedure for silk sericin is presented, employing a protein macroinitiator and atom transfer radical polymerization (ATRP). This study aims to elucidate the significance of the grafting process in tailoring the structure of sericin through the chemistry of synthetic grafts. The grafting procedure uses block copolymers of N‐isopropylacrylamide (NIPAM) and 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS), such as Poly‐(AMPS‐block‐NIPAM)/Poly‐(NIPAM‐block‐AMPS). The procedure employs both one‐step and two‐step synthesis methods to produce a well‐defined, biofunctionalized sericin. Subsequently, sericin‐based nanoparticles are prepared, demonstrating the significance of the optimized procedure. The synthesized products undergo structural analysis using H‐NMR, FTIR‐ATR, XPS, DLS, and zeta potential measurements. In addition, their thermal behavior is assessed using differential scanning calorimetry. To further investigate the prepared nanoparticles, SEM and DLS analyses are conducted. Through synthesis optimization, position and length of each synthetic block is precisely determined, significantly influencing properties of the grafted products and characteristics of the resulting nanoparticles.

Anatomical study of the limited osteotomy suture button fixation Latarjet procedure with coracoacromial ligament preservation

To investigate the morphological characteristics of the glenohumeral joint (including the glenoid and coracoid) in the Chinese population and determine the feasibility of designing coracoid osteotomy based on the preoperative glenoid defect arc length by constructing glenoid defect models and simulating suture button fixation Latarjet procedure. Twelve shoulder joint specimens from 6 adult cadavers donated voluntarily were harvested. First, whether the coracoacromial ligament and conjoint tendon connected was anatomically observed and their intersection point was identified. The vertical distance from the intersection point to the coracoid, the maximum allowable osteotomy length starting from the intersection point, and the maximum osteotomy angle were measured. Next, the anteroinferior glenoid defect models of different degrees were randomly constructed. The arc length and area of the glenoid defect were measured. Based on the arc length of the glenoid defect of the model, the size of coracoid oblique osteotomy was designed and the actual length and angle of the coracoid osteotomy were measured. A limited osteotomy suture button fixation Latarjet procedure with the coracoacromial ligament and pectoralis minor preservation was performed and the position of coracoid block was observed. All shoulder joint specimens exhibited crossing fibers between the coracoacromial ligament and the conjoint tendon. The vertical distance from the tip of the coracoid to the coracoid return point was 24.8-32.2 mm (mean, 28.5 mm). The maximum allowable osteotomy length starting from the intersection point was 26.7-36.9 mm (mean, 32.0 mm). The maximum osteotomy angle was 58.8°-71.9° (mean, 63.5°). Based on the anteroinferior glenoid defect model, the arc length of the glenoid defect was 22.6-29.4 mm (mean, 26.0 mm); the ratio of glenoid defect was 20.8%-26.2% (mean, 23.7%). Based on the coracoid block, the length of the coracoid osteotomy was 23.5-31.4 mm (mean, 26.4 mm); the osteotomy angle was 51.3°-69.2° (mean, 57.1°). There was no significant difference between the arc length of the glenoid defect and the length of the coracoid osteotomy ( P>0.05). After simulating the suture button fixation Latarjet procedure, the highest points of the coracoid block (suture loop fixation position) in all models located below the optimal center point, with the bone block concentrated in the anteroinferior glenoid defect position. The size of the coracoid is generally sufficient to meet the needs of repairing larger glenoid defects. The oblique osteotomy with preserving the coracoacromial ligament may potentially replace the traditional Latarjet osteotomy method.

A critical analysis and prediction of heat transfer and flow characteristics in the sudden expansion channel with square block using machine learning

In this article, the numerical simulation of a 2D flow in an SEC (Sudden expansion channel) with a square block as a VG (Vortex generator) is performed using FVM (Finite volume method) in Ansys FLUENT 2022 R1. A square block of 5x5 mm is deployed in the SEC having ER = 2 (Expansion ratio). The impact of vortex dynamics on heat interaction amplification and fluid flow attributes are observed for various values of Re ranging from 117 to 583. The vortex dynamics for q = 500, 750, and 1000 W/m2 have been thoroughly investigated for different positions of the square block. The working fluid is water that flows in an SEC with a square block at the step, 10, 20, 30, and 40 mm. Machine learning algorithms were utilized to forecast the most advantageous conditions of input variables, including block position, heat flux (q), and Re number, in order to achieve the highest possible overall performance factor (OPF). It is predicted that the maximum OPF is achieved for Re = 640 when the block is placed 30 mm from the step on the bottom wall.

The influence of bone block graft position on bone dimensional changes in staged onlay horizontal ridge augmentation: A 6-month retrospective cohort study.

To analyze changes in bone dimensions and their modulating factor in bone dimensions 6 months after horizontal ridge augmentation using autogenous bone grafts. Thirty-eight patients with horizontally atrophic alveolar ridges of a single edentulous tooth at the maxillary anterior site were divided into two groups based on the fixation position of the bone block during ridge augmentation surgery (H0, vertical distance from the upper edge of the bone block to the alveolar crest). Patients were classified into a crestal level (CL) group if H0 ≤ 1 mm and a sub-crestal level (SCL) group if H0 > 1 mm. The width and height of the alveolar ridge were recorded using CBCT both before and 6 months after the augmentation procedure. The CL group comprised 20 patients with 23 implants, whereas the SCL group comprised 18 patients with 22 implants. All the augmentation sites exhibited vertical bone resorption. Vertical bone resorption in the SCL group (1.94 ± 2.11 mm) was significantly higher than that of the CL group (0.61 ± 0.64 mm). The SCL group showed significantly lower horizontal bone gain than the CL group (SCL: 1.02 ± 2.30 mm; CL: 3.19 ± 3.17 mm) at the cervical level. Peri-implant marginal bone loss increased significantly in the SCL group (1.00 ± 2.71 mm) compared to the CL group (0.64 ± 0.40 mm). The bone height decreased after horizontal ridge augmentation using autogenous onlay grafting. The fixation position of the bone block was a modulating factor. The SCL group showed more vertical bone loss, less horizontal bone gain 6 months after surgery, and more marginal bone loss after restoration.

Evaluating Multi-target Regression Framework for Dynamic Condition Prediction in Wellbore

In recent years, the focus has shifted towards leveraging physics-based modelling and data-driven analysis to predict drilling incidents and anomalies in real time, with the goal of reducing non-productive periods. However, much of this attention has directed at specific drilling operations like drilling and tripping, leaving other vital processes, such as wellbore conditioning, comparatively overlooked. The primary objective of this study is to employ data-driven techniques for predicting the dynamic state of the wellbore by utilising sensor data, operating parameters, and surface measurements. Accurate predictions are pivotal for automating these processes, promising significant savings in both redundant time and associated costs, ultimately elevating operational efficiency.In this research, the surface drilling parameters such as flowrate, rotation speed, block position, and drill string length are incorporated with the surface measurements such as hookload, pressure, and torque during wellbore conditioning operation to predict further surface sensor measurements. Different parameter settings are evaluated to find the best approach. Six supervised learning algorithms are used to select the best prediction method. The findings reveal that considering all surface parameters and measurements yields the most accurate predictions. Among various single and multi-target regression methods, including deep learning approaches, the Gaussian process and random forest models exhibit the lowest prediction errors.By reliably predicting and understanding wellbore behaviour, this research paves the way for more efficient and autonomous drilling operations in the future, bridging a critical gap in the industry's automation capabilities.

Examining Position Effects on Students’ Ability and Test-Taking Speed in the TIMSS 2019 Problem-Solving and Inquiry Tasks: A Structural Equation Modeling Approach

Position effects occur when changes in item positions on a test impact the test outcomes (e.g., item parameters or test scores). Previous studies found that position effects may vary by the testing context and conditions and thus affect each test-taker differently. With the increasing adoption of digital assessments involving innovative item types that are focused on problem-solving skills, it is also essential to study position effects within this context. This study incorporates item-level scores and screen-level response time data from the Trends in International Mathematics and Science Study (TIMSS) 2019 problem-solving and inquiry tasks for Grade 4 students to examine position effects on students’ ability and test-taking speed. This dataset included responses from 27,682 students from 36 countries. A structural equation modeling approach was employed to model ability and test-taking speed within the same model. The results indicated a small but statistically significant booklet effect on students’ overall mathematics and science ability. The impact of block position changes within the booklets seemed to be greater than the impact of a reordering of subjects tested in the two sessions. The results also showed that when an item block was placed earlier in a test session, students spent more time on the items and performed better. The implications of these findings are discussed.

Intelligent Extraction of Multi-style and Multi-template Title Block Information Based on Fuzzy Matching

ABSTRACT Title blocks are crucial primary data on drawings necessary for the operation of modern manufacturing enterprises. However, their uniform export poses a challenge due to the heterogeneity across multiple sources and the variety of export templates. Therefore, this paper proposes an intelligent extraction method for title block information (TBI) based on fuzzy matching. This method evaluates the geometrical composition of the title block, the logical relationship between information cells, and the diversification of the title block. It establishes a weighted intersection point matrix for the title block as the topological structure model. The fuzzy matching, based on the intersection matrix points, disregards the variations in the size and position of the title block and focuses only on the style that impacts the extraction of information. The matched title blocks are categorized, and the base table of each type determines the information distribution of the title block. A hash table is then created between the description cell and the value cell of information to accumulate the TBI. The method is integrated into the AutoCAD software and presented with an interactive program interface. Finally, an example is presented to further demonstrate the stability, reliability, and efficiency of the method and the system.

The arthroscopic Latarjet procedure with a posterior guided system and suture-button fixation enables more precise bone block positioning in the axial plane versus anterior screws fixation.

Adequate position of the bone block during arthroscopic Latarjet procedure is critical for an optimal functional outcome. However, this procedure is complex with a long learning curve. Our aim was to compare the bone block position between a dedicated glenoid posterior instrumentation and suture button fixation versus an anterior screw fixation, on a postoperative computed tomography (CT) scan. Seventy-nine consecutive patients operated on for an anterior shoulder instability were included in this retrospective study. The same surgeon performed arthroscopically the Latarjet procedure either with an anterior drilling and screw fixation (Group A), or with a specific posterior glenoid guide pin, a posterior drilling, and a suture cortical button fixation (Group B). Evaluations were made by two independent observers. The position was evaluated by CT scan in the axial and sagittal planes. Learning curves with operative time, complications and clinical outcomes were assessed at a minimum of 2 years of follow-up. Thirty-five patients were included in Group A and 44 in Group B. In Group A, 27 bone blocks were flush (87.1%) and 38 in Group B (92.7%) (p < 0.01). In Group A, 72% of the bone block height was below the equator and 76%, in Group B (ns). The mean operating time was 123 ± 32.5 min in Group A and 95 ± 34.1 min in Group B (p < 0.0001). At the final follow-up, the mean aggregate Rowe score was respectively 94.6 ± 10.4 and 93.1 ± 9.8 points in Groups A and B. The mean aggregate Walch-Duplay score was respectively 94.2 ± 11.6 and 93.4 ± 10.6 points in Groups A and B. There were 11 complications (31.4%) in Group A and five complications (11.3%) in Group B (ns). The arthroscopic Latarjet procedure with a posterior drilling guided system and suture-button fixation allows more precise positioning in the axial plane than with anterior drilling and screw fixation. This posterior-guided procedure could reduce intraoperative and short-term complications. Level IV.