bluuebunny/crossref_metadata_2025 huggingface dataset:
The Conflict, Climate Change, and Displacement Nexus Revisited: The Protracted Rohingya Refugee Crisis in Bangladesh
Authors: Neef Katja , Jones Evan , Marlowe Jay
Published: August 2023

This article examines the relationships between conflict, climate change, and disaster in forced displacement contexts. We present these nexus dynamics through the case of Rohingya refugees in Bangladesh who are exposed to climatic hazards and other vulnerabilities that threaten their lives and livelihoods. Having fled persecution by the Myanmar military, Rohingya refugees face a range of conflict- and climate-related risks, both in the overcrowded and disaster-prone camps in Cox's Bazar and on the island of Bhasan Char where Bangladeshi authorities have relocated tens of thousands of people. The protracted refugee crisis has exacerbated social tensions between the Rohingya and host communities; limited access to resources and exposure to significant hazards that exacerbate conflict-induced displacement challenges. This paper contributes to the nascent literature on the region's conflict, climate change, and disaster displacement nexus by examining how cascading risks and state fragility contribute to increased instability. The article demonstrates the need for a more nuanced understanding of how conflict-induced displacement leads to new threats and vulnerabilities in hazard-prone environments.
Predictive Value of qEEG in Manic Switch of Depressed Patients
Authors: Arıkan Mehmet Kemal , İlhan Reyhan , Özulucan Mahmut Taha , Esmeray Muhammed Taha , Günver Mehmet Güven
Published: August 2023

Backgrounds: More than half of the patients with bipolar disorder (BD) had depressive episodes at the onset of BD. Despite some suggested clinical predictors, there are no certain criteria for predicting which unipolar depression patient switch to manic episodes during the treatment course. Electrophysiological markers can address this issue. Methods: Pretreatment quantitative electroencephalography (qEEG) records of patients diagnosed with major depressive disorder (MDD) or BD at the first visit were included in the study. Patients with MDD were also grouped with manic switch (MS) or MDD based on the diagnosis of later visits. The qEEG spectral power was analyzed across 3 groups, that is, MS, MDD, and BD. Results: Compared to patients whose diagnosis did not change, patients with MS had accelerated high-frequency activities predominantly in the left hemisphere (central-parietal-occipital regions). In contrast, they showed increased slow wave activity predominantly in the right hemisphere (parietal-occipital regions). Conclusion: It can be concluded that searching for electrophysiological markers, which have distinct advantages of repeatability, noninvasiveness, and cost-effectiveness, can facilitate the prediction of the MS.
A Typology of Metagamers: Identifying Player Types Based on Beyond the Game Activities
Authors: Kahila Juho , Valtonen Teemu , López-Pernas Sonsoles , Saqr Mohammed , Vartiainen Henriikka , Kahila Sanni , Tedre Matti
Published: August 2023

Previous research on player profiles or types is based on players’ in-game behaviors and their motivations to play games. However, there are many other activities related to digital games beyond playing the games properly. Using learning analytics methods, the study investigates the prevalence and interconnections between these different metagame activities and classifies gamers based on their use thereof into distinct profiles. The results show that digital game–related information-seeking activities are key metagame activities with connections to other metagame activities. Three distinct profiles of players were identified based on their metagame activities: versatile metagamers, strategizers, and casual metagamers. The results contribute to the existing literature on metagaming and provide insights for game studies, game design and marketing, and digital games and learning.
Human Subjects Research Guidelines for Undergraduate Researchers: An Analysis of Institutional Review Board (IRB) Websites at Top Liberal Arts Colleges in the United States
Authors: Marcos Miguel Nausica , Noy Shiri
Published: August 2023

Teaching students about the ethics of Human Subject Research (HSR) should be a fundamental component of students’ education about research. In this article, we analyze the Institutional Review Board (IRB) websites of top-ranked Liberal Arts Colleges (LACs) to examine their framing of HSR carried out by undergraduate students. Our descriptive quantitative analysis from 50 top-ranked LACs in the United States indicates that a majority of IRB websites provide information about undergraduate research, and most include information about students’ classroom-based research. Our qualitative content analysis of a subsample of ten colleges’ IRB websites provides information on how they inform and educate about issues including informed consent and highlight different resources for students including their research advisor, and disciplinary standards. We conclude by discussing recommendations for IRBs in their accessibility to undergraduates.
Blinding Models for Scientific Peer-Review of Biomedical Research Proposals: A Systematic Review
Authors: Qussini Seba , MacDonald Ross S. , Shahbal Saad , Dierickx Kris
Published: August 2023

Objective: The aim of this systematic review is to estimate: (i) the overall effect of blinding models on bias; (ii) the effect of each blinding model; and (iii) the effect of un-blinding on reviewer's accountability in biomedical research proposals. Methods: Systematic review of prospective or retrospective comparative studies that evaluated two or more peer review blinding models for biomedical research proposals/funding applications and reported outcomes related to peer review efficiency. Results: Three studies that met the inclusion criteria were included in this review and assessed using the QualSyst tool by two authors. Conclusion: Our systematic review is the first to assess peer review blinding models in the context of funding. While only three studies were included, this highlighted the dire need for further RCTs that generate validated evidence. We also discussed multiple aspects of peer review, such as peer review in manuscripts vs proposals and peer review in other fields.
Effects of step-by-step line balancing in apparel assembly line
Authors: Kim Minsuk , Kim Sungmin
Published: August 2023

The mixed work assignment technique was applied to the modular production concept to solve the apparel assembly line balancing problem. Specifically, an algorithm was implemented to generate workstations by first classifying tasks into modules through an analysis of the manufacturing process and assigning grouped tasks in the single task–multiple workers and multiple tasks–single worker assignment methods. Then, worker assignment was sequentially performed considering the skill level of the worker. A simulation of producing 100 men’s shirts was performed. Owing to line balancing, the total production time was considerably lower than that reported in previous studies. The enhanced performance was attributable to the fact that unlike previous studies that limited the apparel assembly line balancing problem to worker assignment, line balancing was performed through both task and worker assignment in this study. The results demonstrated that task assignment must be considered in the design stage in the apparel assembly line balancing problem.
Influence of the shutdown process of the driveline on the generator bearing life in the diesel generator set
Authors: Song Shizhe , Huang Yan , Hua Chunrong , Dong Dawei , Yan Bing
Published: August 2023

Diesel generator sets are commonly used as power sources in transportation due to their versatility and cost-effectiveness. During the shutdown process, the diesel engine’s cylinder compression pressure would cause forced vibration in the driveline system through the crank linkage mechanism, resulting in unsteady loads that pose a threat to the bearing life. To address this issue, a coupling forward design method is proposed that takes into account the impact of unsteady loads on bearing life. An experiment was conducted on a 16V280 diesel generator set shutdown process, and a driveline dynamic model was established. The cumulative damage value that connects unsteady loads and bearing life was introduced to quantify the effect of unsteady loads on the bearing life during the shutdown process. The unsteady loads included torque fluctuation and collision forces. The results showed that reducing the driveline key gap and increasing the coupling stiffness can decrease the combined load on bearings and improve bearing life. A large stiffness coupling was designed to achieve shutdown smoothness and a 43.19% reduction in bearing life damage, confirming the design method’s feasibility concerning bearing life.
Shifting the Level of Selection in Science
Authors: Tiokhin Leo , Panchanathan Karthik , Smaldino Paul E. , Lakens Daniël
Published: August 2023

Criteria for recognizing and rewarding scientists primarily focus on individual contributions. This creates a conflict between what is best for scientists’ careers and what is best for science. In this article, we show how the theory of multilevel selection provides conceptual tools for modifying incentives to better align individual and collective interests. A core principle is the need to account for indirect effects by shifting the level at which selection operates from individuals to the groups in which individuals are embedded. This principle is used in several fields to improve collective outcomes, including animal husbandry, team sports, and professional organizations. Shifting the level of selection has the potential to ameliorate several problems in contemporary science, including accounting for scientists’ diverse contributions to knowledge generation, reducing individual-level competition, and promoting specialization and team science. We discuss the difficulties associated with shifting the level of selection and outline directions for future development in this domain.
Human Crowds as Social Networks: Collective Dynamics of Consensus and Polarization
Authors: Warren William H. , Falandays J. Benjamin , Yoshida Kei , Wirth Trenton D. , Free Brian A.
Published: August 2023

A ubiquitous type of collective behavior and decision-making is the coordinated motion of bird flocks, fish schools, and human crowds. Collective decisions to move in the same direction, turn right or left, or split into subgroups arise in a self-organized fashion from local interactions between individuals without central plans or designated leaders. Strikingly similar phenomena of consensus (collective motion), clustering (subgroup formation), and bipolarization (splitting into extreme groups) are also observed in opinion formation. As we developed models of crowd dynamics and analyzed crowd networks, we found ourselves going down the same path as models of opinion dynamics in social networks. In this article, we draw out the parallels between human crowds and social networks. We show that models of crowd dynamics and opinion dynamics have a similar mathematical form and generate analogous phenomena in multiagent simulations. We suggest that they can be unified by a common collective dynamics, which may be extended to other psychological collectives. Models of collective dynamics thus offer a means to account for collective behavior and collective decisions without appealing to a priori mental structures.
Strategies, debates, and adversarial collaboration in working memory: The 51st Bartlett Lecture
Authors: Logie Robert H
Published: August 2023

Frederic Bartlett championed the importance of individual strategy differences when remembering details of events. I will describe how long-running theoretical debates in the area of working memory may be resolved by considering differences across participants in the strategies that they use when performing cognitive tasks, and through adversarial collaboration between rival laboratories. In common with the established view within experimental cognitive psychology, I assume that adults have a range of cognitive functions, evolved for everyday life. However, I will present evidence showing that these functions can be engaged selectively for laboratory tasks, and that how they are deployed may differ between and within individuals for the same task. Reliance on aggregate data, while treating inter- and intra-participant variability in data patterns as statistical noise, may lead to misleading conclusions about theoretical principles of cognition, and of working memory in particular. Moreover, different theoretical perspectives may be focused on different levels of explanation and different theoretical goals rather than being mutually incompatible. Yet researchers from contrasting theoretical frameworks pursue science as a competition, rarely do researchers from competing labs work in collaboration, and debates self-perpetuate. These approaches to research can stall debate resolution and generate ever-increasing scientific diversity rather than scientific progress. The article concludes by describing a recent extended adversarial collaboration (the WoMAAC project) focused on theoretical contrasts in working memory, and illustrates how this approach to conducting research may help resolve scientific debate and facilitate scientific advance.
Comparing three observation instruments of the coach's behaviour in grassroots football
Authors: Ordeix Lídia , Viladrich Carme , Alcaraz Saul
Published: August 2023

Coach behaviour has long been known to influence the sporting experience of grassroots players; however, it is currently unclear how the instruments used to assess their behaviour are related. Therefore, the aim of this study is to evaluate the relationships between three observational coaching behaviour tools. Sixteen matches with teams led by four female football coaches were recorded and analysed using three observational instruments: (a) Coaching Behaviour Assessment System (CBAS); (b) Multidimensional Motivational Climate Observation System (MMCOS) and (c) Coach Leadership Assessment System (CLAS). The dimensions measured by each instrument are theorised as being adaptive or maladaptive. The specific objectives of this study are targeted to assess: (a) the commonalities between the three instruments and (b) what differentiated aspects each instrument provides. The results show that both the adaptive and the maladaptive dimensions of the three instruments are positively related among themselves but negatively related to the others. The results also show that the MMCOS is sensitive to behavioural changes during the matches, while the CBAS and the CLAS do not reflect these changes but assess the stability of the behaviour. In conclusion, this research provides empirical evidence supporting the conceptual relationship between the three instruments and of the specific information that each instrument offers. Furthermore, it highlights the need to observe the sport environment more closely in a more diversified way.
Relations between empowering and disempowering motivational climate with burnout, fear of failure and grit
Authors: Birr Caroline , Hernández-Mendo António , Monteiro Diogo , Brandão Regina , Rosado António
Published: August 2023

The coach-created motivational climate refers to the environmental factors that influence the athletes’ emotional, cognitive, physical and social experiences and could be more or less empowering. The present study aimed to determine the connection between the empowering and disempowering motivational climate (EDMC) with other variables, from several sports (328 males and 118 females; M age = 17.60 years; SD = 6.27) completed questionnaires assessing perceptions of coach-created motivational climates, burnout, fear of failure and grit. Structural equation modeling revealed that the empowering motivational climate is negatively related with burnout and with fear of failure. In addition, the disempowering motivational climate is positively related with burnout and with fear of failure. In turn, the grit dimension, perseverance of effort, was not significantly associated with burnout; it showed, however, a significantly negative association with fear of failure. The EDMCs were not related with grit-perseverance of effort and grit-consistence of interests. Overall, this study suggests that creating empowering environments can play a crucial role in mitigating emotional and physical exhaustion, as well as the fear of failure that athletes often experience in the context of sports.
Injuries in padel players: What is known? A scoping review
Authors: Giustino Valerio , Figlioli Flavia , Patti Antonino , Vicari Domenico Savio Salvatore , Alamia Giuseppe , Palma Antonio , Romualdo Castillo-Lozano , Thomas Ewan , Bianco Antonino
Published: August 2023

Background

Padel has spread rapidly in several countries around the world. Although this racket sport seems to have several health benefits, the number of scientific papers on this sport is still very few. This scoping review aimed to systematically map the evidence regarding injuries in Padel players by identifying, synthesizing, and assessing the studies currently existing in the scientific literature.

Methods

This scoping review was conducted following the guidelines provided by the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews and the Population, Concept, Context framework was adopted. Articles were collected from PubMed, Web of Science, and Scopus.

Results

A total of seven studies were included in this review. The most frequent injury location is in the elbow, followed by shoulder, and low back. As for lower limbs, knee represents the most affected body region. Although not all the studies included described the type of injuries, tendon, joint, and muscle are the body structure most injured.

Conclusion

This scoping review can aid in a better comprehension of the location and type of injuries that occur in Padel players. However, it is worth noting that all the studies existing concerns nonprofessional athletes. Hence, these findings could be useful to coaches as they add knowledge on the risk of injury in padel that can allow the planning of suitable training programs for amateur and recreational players in order to prevent injuries.
Integrating discoverability and prominence in video-on-demand consumption choices. A qualitative user study in Belgium
Authors: Iordache Catalina , Loisen Jan , Audenhove Leo Van
Published: August 2023

As video-on-demand services have taken a central position in audiovisual distribution in European markets, over-the-top viewing has become increasingly popular. This shift has heavily impacted consumption patterns and exposure diversity, as they are reshaped by non-linear distribution and technological affordances. This article aims to integrate debates on discoverability and prominence within wider research on video-on-demand consumption. It does so by widening the existing focus on the strategies deployed by video-on-demand services to capture users’ contexts and actions in the consumption decision-making process. The framework is based on exploratory qualitative research conducted in Belgium through a diary study and in-depth interviews and can contribute to future audience research on video-on-demand consumption choices. We find that users discover and choose audiovisual content to consume on demand through a combination of formal and informal factors. These are grouped into four thematic categories, namely technological affordances, perceived offering, external ‘nudges’, and process.
Management and outcome of obstructive airway complications after lung transplantation – a 12-year retrospective cohort study
Authors: Gottlieb Jens , Fuehner Thomas , Zardo Patrick
Published: August 2023

Background:

Obstructive airway complications (OACs) represent a significant problem after lung transplantation (LTx). Bilateral OACs after double lung transplantation are infrequently reported.

Objectives:

The aim of this study was to investigate management and outcome of OAC.

Design:

Retrospective single-center cohort study

Methods:

Adult patients with bilateral LTx performed between 2010 and 2021 were included. Patients with follow-ups of less than 3 months and after heart–lung transplantation were excluded. OAC was defined either as the need for stenting, surgical revision, or balloon dilatation. Outcome parameters included graft survival, graft function, quality of life, and management.

Results:

During the study period, 1,170 patients were included. Hundred thirty-five (11.5%) patients developed OAC. Forty-six (4.4%) patients had significant bilateral OAC. Thirty-seven (80%) bilateral OAC patients were treated by stent insertion; in 34 patients, biodegradable stents were used. The median number of bronchoscopies in bilateral OAC was 26 during the first postoperative year compared with nine in controls ( p < 0.001). Fourteen OAC patients ( n = 10 bilateral) underwent surgical revision including six re-do transplantations. Graft loss occurred significantly more frequently in patients with bilateral OAC with a graft survival of 63% and 50% in these after 3 and 5 years compared with 83% and 73% in controls without OAC ( p < 0.001). Baseline forced expiratory volume in 1 s (FEV1) in patients with bilateral OAC was median 58% predicted in comparison with 90% in controls ( p < 0.001). Quality of life was significantly reduced.

Conclusion:

Bilateral OACs impose a high burden of disease on patients after lung transplantation and were associated with early and late graft loss. Affected patients’ OAC demonstrated reduced graft function and impaired quality of life. Most OACs were managed by bronchoscopy preferably by non-permanent stenting. Surgery including re-do transplantation was used in selected cases.
Cauda equina syndrome: Recognising ‘red flags’ for back pain in primary care
Authors: Williams Mr John T. , Poon Dr Henry , Pumphrey Dr James , Kathirgamakarthigeyan Dr Narayani , Fakouri Mr Bahram , Panchmatia Mr Jaykar R.
Published: August 2023

Cauda equina syndrome is a rare, but potentially devastating condition caused by compression of the lumbosacral nerve roots, usually due to a massive disc herniation. Missed or delayed diagnosis leads to lower limb paralysis with bowel, bladder and sexual dysfunction. The aims of the article are to describe the pathophysiology, epidemiology, typical presentation, diagnostic features and red flag symptoms, presented in line with the RCGP curriculum topic guide. We have included guidance for GPs undertaking clinical assessments, including telephone appointments. This article also includes referral pathways to specialist services, long-term follow-up and community support services for these patients.
Patterns of participation in early childhood education before and during the COVID-19 pandemic in Australia
Authors: Molloy Carly S , Guo Shuaijun , Goldfeld Sharon
Published: August 2023

The COVID-19 pandemic has profoundly affected children’s care and education worldwide. This article reports on patterns of participation in early childhood education and care (ECEC) across Australia as influenced by the COVID-19 pandemic and national policies. Using ECEC data from Xplor – a software platform used across Australian childcare centres (2019: n = 229,349; 2020: n = 229,468), patterns of attendance rates were examined nationally in 2019 and 2020 by service-level and family-level characteristics. The average attended hours per week of ECEC nationally in 2020 (18.32 hours) was less than that in 2019 (21.26 hours). Attendance rates at ECEC in 2020 declined rapidly from 66% to 26.2% at the onset of the COVID-19 outbreak. Fee-free subsidy from Australian governments did not substantially increase attendance or reduce disparities in attendance for vulnerable families. Low ECEC attendance rates for prolonged periods could have significant implications for child development, particularly for children from vulnerable backgrounds.
Oil extraction and Indigenous women: Examining the necropolitics of the settler state in the Bakken region
Authors: Chase Marie , Johnson Adrienne
Published: August 2023

Emerging research shows that the health and well-being of Indigenous women is increasingly jeopardized in areas close to oil extraction due to heightened violence and criminal behavior. Our empirical findings reveal how the oil industry has impacted one Indigenous reservation located in the Bakken region—an area experiencing a major “boom” in shale extraction activities. We find that sexual assault and violence against Indigenous women has increased due to three settler tactics: (1) gendered economic inequalities and tribal divisiveness entrenched by structural poverty and uneven oil-derived wealth distribution, (2) industrialized “man-camps” and “risky” behaviors associated with transient oil workers, and (3) confusing jurisdictional spatialities structured by overlapping tribal authority and federal law. Employing a Native feminist reading of Mbembé's necropolitics, we argue that the above tactics coalesce to form a spatial formation where Indigenous women are made vulnerable to death through the necropower of the settler state, and tribal governments are not able to criminally prosecute non-Native individuals involved in violent crimes on tribal lands. Multi-scalar pathways forward include support for Indigenous-led activism that enhances public awareness and efforts that protect the livelihoods and futures of all Indigenous peoples. The restoration of tribal sovereignty is also supported with the understanding that, unfortunately, this form of sovereignty continues to be highly circumscribed by the settler state.
Lessons in accumulated rage and rebellious scholarship with Mike Davis
Authors: Lara Juan De
Published: August 2023

This essay reflects on the ways that Mike Davis's commitment to social justice shaped his pedagogical practice and mentorship. It uses the author's personal experiences to highlight Davis's support for devalued communities and overlooked places. More specifically, the essay provides examples that show how Davis created new platforms that amplified marginalized voices. Finally, the author uses current research on the Salton Sea and the Coachella Valley to illustrate how Davis's intellectual contributions generated valuable epistemic frameworks for those interested in social and ecological justice.
To which prosecution service? Analyzing the way the Union resolves conflicts of criminal jurisdiction
Authors: Zuidema Andrew
Published: August 2023

Conflict of jurisdiction is an issue that is not a new problem, but is one that is becoming more prevalent in recent times. This is especially true in the European Union with its four freedoms. One way the Union has tackled conflicts of jurisdiction is through Framework Decision 2009/948/JHA. This measure is designed to handle positive conflicts of jurisdiction, in particular attempting to prevent ne bis in idem violations. Recently the Union established the European Public Prosecutor’s Office, a new measure designed to not only resolve positive conflicts of jurisdiction, but negative ones as well. This article will highlight that the EPPO is not only a prosecution service but also a way to resolve conflicts of jurisdiction. It will do this by conducting a comparative analysis between the two measures by reviewing their respective function, communication, and determination of jurisdiction. Function examines what each measure is capable of doing. Communication examines the way authorities communicate and share information. Determination of Jurisdiction examines the criteria that is used by the mechanism to resolve the conflict. Using these methods will enhance our understanding of the measures the Union has to resolve conflicts of jurisdiction while also highlighting the role that EPPO will play in the years to come.
Concurrent strangulated obturator hernia and femoral hernia repair via TAPP approach: A case report
Authors: Nguyen Minh Thao , Nguyen Van Quy
Published: August 2023

An obturator hernia is a rare pelvic hernia with high mortality. Early diagnosis and treatment are essential to reduce postoperative complications. The treatment of choice for obturator hernias is surgery. In an emergency, laparotomy to resolve herniated viscera and complications is often the choice. However, some researchers have shown the feasibility of laparoscopy. The laparoscopic approach has several benefits over the open approach, including reduced postoperative pain, early mobilization, shorter length of stay, and lower postoperative morbidity rates. We report the case of an 81-year-old woman with a right-side obstructed obturator hernia. The patient was hospitalized with an acute onset of inner thigh pain and bowel obstruction. The obturator hernia was diagnosed preoperatively by an abdominopelvic CT scan with the image of protrusion of an ileal loop in the right obturator foramen. The patient was treated by an emergency laparoscopy. The right obturator hernia and a concurrent right femoral hernia were confirmed during the operation. The hernia defect was repaired with a mesh large enough to cover all hernia foramen. The patient recovered without any complications. Emergency laparoscopic repair for obstructed obturator hernia was safe and effective.
Could classic psychedelics influence immigrants’ acculturation process? A narrative review contemplating how
Authors: Korman Benjamin A.
Published: August 2023

Rising international migration, paired with increasing public support for far-right political parties, poses a growing challenge to the countries tasked with successfully integrating immigrants into their society. Further complicating this matter is the fact that the acculturation process which immigrants undergo to fully integrate into their host society can be long, difficult, and taxing to their mental health, physical health, and sense of belonging. A better understanding of how the unique burdens faced by immigrants might be alleviated or more easily processed is therefore vital for the success of both immigrants and their host countries. Drawing on initial findings suggesting that classic psychedelics can help individuals process incidents of discrimination, make healthier decisions, and experience deeper feelings of connectedness to others, this literature review presents a roadmap for determining what classic psychedelics may offer immigrants, a large and rapidly growing international minority group.
Returning home for a better job? Return migration, family background, and labor market outcomes among recent college graduates in China
Authors: Zhao Mengyao
Published: August 2023

In previous studies of migration, return migration is usually considered a behavior determined by negative self-selection. This study pools data from three waves of the China College Student Survey (2010, 2013, and 2015) to explore the return migration behavior of Chinese college graduates and its impact on their labor market performance. The results show that graduate return migrants have advantages in terms of family background, although they do not perform as well in terms of human capital. Relative to graduate nonreturn migrants, return migrants have a greater chance of securing positions in governmental organizations, and this advantage is reinforced by family political capital. In addition, income analysis shows that return migrants seem to have an advantage over nonreturn migrants when the effects of migrant selectivity are considered. This study systematically discusses the monetary and occupational returns to return migration of highly educated individuals in a non-Western context, and has important implications for our understanding of the relationship between migration and social inequality.
Compression of the Ulnar Nerve Following Carpal Tunnel Release
Authors: Robbins Liam , Lovy Andrew , Gillis Joshua
Published: August 2023

Given the proximity and shared structures of Guyon's canal and the carpal tunnel, compression of the ulnar nerve is a rarely observed but possible complication of carpal tunnel release. In this case report, a patient underwent previous carpal tunnel release and immediately experienced ipsilateral hand weakness in keeping with an ulnar nerve compression syndrome. Clinical, electrodiagnostic, and magnetic resonance imaging findings after carpal tunnel release demonstrated a compression or injury to the deep motor branch of the ulnar nerve not previously present. Subsequent release of Guyon's canal identified a separate compartment of the deep motor branch of the ulnar nerve within the ulnar leaflet of the transverse carpal ligament. After the release of the motor branch from this compartment, the patient experienced recovery from their neuropathic symptoms. This case report outlines the relevant anatomy and clinical data surrounding an anomalous compartment of the deep motor branch of the ulnar nerve.
Effect of the 2018 NCAA Kickoff Rule Change on Concussion Rates in Collegiate Football: Results From a Division 1 Conference
Authors: Whelan Bridget M. , Harmon Kimberly G , Aukerman Douglas F , Konstantinides Niki A , Poddar Sourav K , Bohr Adam D
Published: August 2023

Background:

Kickoff plays in American football are associated with an increased risk of concussion compared with other play types. In 2018, the National Collegiate Athletic Association (NCAA) Football Rules Committee altered the kickoff rules so a fair catch inside the 25-yard line results in a touchback, with the ensuing drive starting on the 25-yard line. The intention was to decrease the number of kickoff returns with a corresponding decrease in the rate of concussions on kickoff plays.

Purpose:

To determine whether the 2018 rule changes had the intended effects in an NCAA Division 1 Conference.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

The study population included football athletes in the NCAA Pacific-12 (Pac-12) Conference. Data on the total number of plays, punts, kickoffs, touchbacks, and fair catches were obtained for all in-conference games from the 2016 to 2021 seasons. The number of game concussions and the play type were provided by each conference institution. Incidence of concussions occurring during kickoff plays before (2016-2017) and after (2018-2021) the rule change were compared with a difference-in-difference analysis using Poisson general linear models.

Results:

There were 242 concussions in 108,774 total plays in the study period, with an overall concussion rate of 2.2 per 1000 plays. The percentage of touchbacks increased significantly from 45% to 51% ( P < .001) and the percentage of fair catches increased from 1% to 7% ( P < .001) from before to after the rule change. Kickoffs accounted for 6% of plays both before and after the rule change and 11% of concussions before and 14% after the change. The mean annual concussion rate (per 1000 plays) on kickoffs was 3.42 before and 5.31 after the rule change (rate difference: 1.89; 95% confidence interval, -1.22 to 5.01).

Conclusion:

Touchbacks and fair catches increased after the kickoff rule change, but there was not a corresponding decrease in concussions during kickoff plays as anticipated. Concussions occurring during other football plays remained stable.
Paper 01: Distance-to-Dislocation Predicts Recurrent Dislocation and Return-to-Sport Following Latarjet
Authors: Sabzevari Soheil , Reddy Rajiv , Cluts Landon , Sebastiani Romano , Dworkin Joshua , Schmidt Christopher , Lin Albert , Charles Shaquille
Published: August 2023

Objectives:

More recently, the glenoid track has been described as a continuum rather than a binary “on-track/off-track” concept. “Distance to dislocation” (DTD), which defines how far an on-track lesion is from being off-track, has proven to be a strong predictor for recurrent dislocation following arthroscopic Bankart repair. Risk of recurrent instability following a Latarjet as it relates to DTD, however, is unknown. The purpose of this study was to determine if DTD is a predictor of recurrent dislocation and return-to-sport/work (RTS). We hypothesized higher DTD values would correlate with lower failure rates and higher rates of RTS.

Methods:

We retrospectively identified 106 consecutive patients who underwent a Latarjet between 2012 and 2022. Glenoid bone loss, Hills-Sachs Interval (HSI), glenoid track (GT), and DTD ( DTD = GT – HSI) were determined from preoperative MRIs. On-track shoulders corresponded with positive DTD values, while off-track shoulders revealed negative DTD values. Relatedly, the more positive or negative the DTD value, the more on-track or off-track the shoulder. Univariate and multivariate cox regression analyses were utilized to evaluate the association between recurrent dislocation, patient demographics, and DTD. Using parametric survival analysis, we evaluated the association between RTS, demographics, and DTD.

Results:

Seventeen patients (16%) experienced recurrent dislocations. Our cohort was 70% male with an average follow-up of 1.5 years. Patient age (p=0.035), revision status (p=0.033), and DTD (p=0.005) were significant predictors of reoperation on univariate analysis. After adjusting for confounders, only DTD (p=0.043) remained a significant predictor of recurrent instability, Figure 1. Regarding RTS, patient age (p=0.14), sex (p=0.029), and DTD (p<0.0005) were predictive of RTS on univariate analysis. After adjusting for covariates, we observed an interaction between patient age and DTD (p=0.036). More specifically, older patients have a more prolonged RTS at lower DTD values compared to younger patients, Figure 2.

Conclusions:

Regardless of on-track vs off-track status, DTD is a useful variable in the work-up of patients undergoing Latarjet reconstruction. Lower DTD values are predictive of higher rates of recurrent instability and lower rates of RTS, especially in older patients.
Paper 23: Taking the Load Off: Effect of Varus Producing Distal Femoral Osteotomy and High Tibial Osteotomy on Compartment Pressures and Contact Area in Varying Stages of Knee Flexion
Authors: Foster Michael , Su Chuck , Vopat Matthew , Hollenbeck Justin , Brown Justin , Vidal Armando , Liles Jordan
Published: August 2023

Objectives:

Study Objective: Evaluate mean contact area, mean contact pressure, and peak contact pressure in the medial and lateral compartment of the knee following varus producing high tibial osteotomy and distal femoral osteotomy in varying states of knee flexion (0*, 30*, 60*, 90*). Background: Genu valgum causes mechanical pressure to be transferred to the lateral compartment. In patients with valgus alignment and a diseased lateral compartment, both lateral opening wedge distal femoral osteotomy (DFO) and high tibial closing wedge osteotomy (HTO) can be used to unload a diseased lateral compartment of the knee. To the best of our knowledge, there are no biomechanical studies investigating how a DFO and HTO affect lateral compartment contact pressure and area in varying states of flexion. Prior anatomic studies have shown that, in valgus knees, the tibial wear is posterior. Additional, biomechanical studies have indicated that DFO exerts the greatest effect in full extension but it’s effect is decreased as flexion angle rises. Hypothesis: Medial closing wedge high tibial osteotomy will significantly decrease contact area, mean contact pressure and peak contact pressure in the lateral knee compartment through knee flexion to a greater extent compared to lateral opening wedge distal femoral osteotomy.

Methods:

Lateral opening wedge DFO and medial closing wedge HTO was performed, correcting a mean of 8°, in 10 cadaveric knees using plate fixation. Tibio- femoral contact pressure of the medial and lateral compartment was measured in 0°, 30°, 60°, and 90° of knee flexion before and after osteotomy using thin electronic sensors (K-scan Model 4000, 1500 psi; Tekscan Inc, South Boston, MA) and load applied through an Instron device (Instron, Norwood, MA). Peak contact pressure (PCP), average contact pressure (ACP), and contact area (CA) were measured for each condition. Mixed-effects regression analyses were used to compare the change in variables before and after osteotomy and between flexion angles.

Results:

The lateral ACP was significantly decreased in the HTO state when compared to native in 30° (p=0.015), 60° (p=0.0199), and 90° (p<0.0001) of flexion. The lateral ACP was also significantly decreased in the HTO state when compared to the DFO state in 60° (p=0.0093) and 90° of flexion (p<0.0001). Following DFO, the lateral ACP returned to that of the native state in 60° (p=1.000) and 90° (p=1.000) of flexion. The medial ACP was significantly increased when compared to both the native and HTO state in 60° (p<0.001; p=0.015) and 90° (p<0.0001; p=0.0435) of flexion.

Conclusions:

With varus corrections of <10°, medial closing HTO is more effective at unloading the lateral compartment than lateral opening DFO. This effect is amplified as the knee flexion angle increases.
Paper 25: The Impact of Posterior Tibial Slope on Meniscal Injury in Acute ACL Ruptures: A Large, Retrospective Registry Study
Authors: Retzky Julia , Hsu Janet , Arnone Paley , Greditzer Harry , Nawabi Danyal , Marx Robert , Thacher Ryan
Published: August 2023

Objectives:

Increased posterior tibial slope has previously been associated with an elevated risk of anterior cruciate ligament (ACL) rupture. Recent studies have suggested there may be a relationship between posterior slope and meniscal tears in ACL ruptures, however, these studies have either included chronic ACL injuries, revision ACL reconstructions or an overall low number of study participants. The goal of this study is to leverage a large ACL registry to assess the impact of posterior tibial slope on meniscal tears in acute ACL ruptures.

Methods:

A large, single-institution knee registry was consulted to identify all patients between the age of 18 and 45 who underwent primary ACL reconstruction between Jan 2019 and July 2022 for acute, noncontact ACL rupture, defined as undergoing surgery within 90 days of injury. Patients with pre-existing meniscal pathology, chronic ACL reconstructions, revisions, multi-ligament knee injuries and nonoperatively managed ACL injuries were excluded. Preoperative MRIs were used to measure lateral and medial posterior tibial slope for all patients. Meniscal injury seen in-situ during arthroscopy was recorded based on operative reports. Demographics data, including age, sex, and body mass index, was also recorded. Independent cohorts were created based on the presence or absence of any meniscal injury. Two-tailed student’s t tests were used to compare average medial and lateral posterior tibial slopes between these groups. Separate analyses were also performed to assess the impact of posterior slope on medial and lateral meniscus tears independently. Multiple logistic regression was carried out to determine risk factors for meniscal injury in this population.

Results:

1059 patients ultimately met inclusion criteria. The average age was 29.5 and there were 532 (50%) women. There were 253 (24%) patients with isolated lateral meniscus tears, 152 (14%) patients with isolated medial meniscus tears and 93 (9%) patients with both medial and lateral tears. The average lateral and medial posterior tibial slopes were 5.54 (-4.2 to 13.4) and 5.67 (0 to 15.7), respectively. Increased lateral tibial slope was associated with a statistically significant increase in rate of any meniscal tear (p=.0022). Lateral slope was also associated with a higher rate of lateral meniscal tears, specifically (p=.0009). Multiple logistic regression identified elevated BMI and male sex as independent risk factors for meniscal injury in this population.

Conclusions:

Increased lateral posterior tibial slope is associated with a higher rate of meniscus injury in acute ACL ruptures and should be considered when devising treatment algorithms for patients in this population. [Table: see text][Table: see text][Table: see text][Table: see text]
Paper 27: Preoperative Risk Factors of Subsequent Ipsilateral ACL Revision Surgery following an ACL Restoration Procedure
Authors: Sanborn Ryan , Badger Gary , Fleming Braden , Kiapour Ata , Murray Martha , Yen Yi-Meng , Kramer Dennis
Published: August 2023

Objectives:

To identify the preoperative risk factors for revision ACL surgery within the first two years after BEAR ACL repair procedure.

Methods:

Data from the prospective BEAR I, II, and III trials were used to determine preoperative risk factors for ACL revision surgery. All subjects with a complete ACL tear (ages between 13-47 years, depending on the trial), who passed all other inclusion/exclusion trial criteria, and underwent a primary BEAR procedure within 30-50 days from injury (dependent on trial) were included. Demographic data (age, sex, BMI), baseline patient-reported outcomes (IKDC Subjective Score, Marx Activity score), pre-operative imaging characteristics (ACL stump length, notch size, tibial slopes), and intraoperative findings (knee hyperextension, meniscal tear status) were evaluated to determine their contribution to ipsilateral revision ACL surgery risk.

Results:

123 subjects, median age 17.6 years (IQR 16-23), including 67 (54%) females, met study criteria. 18 (15%) patients required revision ACL surgery in the first two years following the BEAR procedure. In bivariate analyses, younger age (p=.011), having a contact injury at the time of the initial tear (p=.048), and increased medial tibial slope (p=.029) were associated with a higher risk of ipsilateral revision surgery. Multivariable logistic regression analyses identified two independent predictors of revision: patient age and medial tibial slope. The odds of an ipsilateral revision surgery were decreased by 32% for each one-year increase in age (OR=0.684, 95% CI = 0.517 to 0.905, p=.008), and increased by 28% per each degree of increase in medial tibial slope (OR=1.280, 95% CI =1.024 to 1.601, p=.030). Sex, baseline IKDC or Marx score, knee hyperextension, or meniscus status were not significant predictors of revision.

Conclusions:

Younger age and higher medial tibial slope were predictors of increased odds of ipsilateral ACL revision surgery after the BEAR procedure. Younger patients with higher tibial slopes should be aware of the increased risk for revision surgery when deciding to undergo ACL restoration surgery.