bluuebunny/crossref_metadata_2025 huggingface dataset:
Contextual factors, transnationalism attitudes, and support for GAL-TAN parties within European metropolises: Insights from London
Authors: Crulli Mirko
Published: August 2023

European democracies are moulded by a ‘transnational cleavage’ between green-alternative-libertarian and traditionalist-authoritarian-nationalist parties and attitudes. The territorial reverberations of this new cleavage are still scarcely analysed. Therefore, this article aims to explore how the transnational cleavage relates to political opinions and choices at the local level, by uncovering connections between such cleavage and the characteristics of metropolitan places. What are the implications of living in different metropolitan contexts on citizens’ positions on the transnational cleavage? I answer this question by investigating how metropolitan contextual factors shape transnationalism attitudes and support for green-alternative-libertarian and traditionalist-authoritarian-nationalist parties within London. Findings highlight that transnationalism attitudes and support for green-alternative-libertarian/traditionalist-authoritarian-nationalist parties are statistically significantly related to contextual factors; among the latter, the boroughs’ housing conditions and ethnic structures are the best predictors of transnationalism attitudes and party choices; residents of disadvantaged metropolitan contexts exhibit lower support for transnationalism and green-alternative-libertarian parties.
There is no such thing as a political conservative
Authors: Smyth Nicholas
Published: August 2023

A great deal of ink has been spilled trying to define political conservatism. Yet, far too many of these definitions have failed to isolate a unified and distinctive set of normative commitments that conservatives can be said to share. This has led some critics to allege that the view has no definition. In this paper, I show that there are in fact two perfectly comprehensible conceptions of the theory that meet these criteria. However, I argue that, given some fairly uncontroversial facts about human institutions, neither version represents a believable political philosophy. I conclude that there are legitimate and distinctive conservative political reasons, but that any attempt to describe these as our sole or primary political reasons is doomed to fail.
The influence of the Programme for International Student Assessment on educational governance situated in the institutional setting of South Korea
Authors: Kim Yong , Choi Tae-Hee
Published: August 2023

The Programme for International Student Assessment (PISA) has instigated educational changes and reforms globally, in particular, introducing and intensifying neoliberal logic and governance in test-taking countries and beyond. PISA outcome impacted upon the educational governance of South Korea as well, however, the changes deviated from what have been observed in other contexts. Framed by institutionalism, and drawing on research reports and literature published on Korea, the paper explores how PISA outcome was appropriated to sustain progressive educational agendas against conservative party’s turn to elitism and competition at a critical juncture. After reviewing the context, Korea’s responses to PISA outcome as captured in educational policies are presented, along with their shapers. The paper highlights how the policy responses parted ways with those of most countries by rehumanizing the curriculum, while acknowledging that its planned new relationship with PISA may turn their course.
Supports and Empowerment for Families of Children with Extensive Support Needs Throughout the COVID-19 Pandemic
Authors: Spann Emilee , Biggs Elizabeth Erin , Ross Madison
Published: August 2023

The COVID-19 pandemic profoundly impacted daily life, including the educational experiences of school-age children with and without disabilities and their families who supported them. This descriptive qualitative study examined the experiences of families with children with extensive support needs and complex communication needs during the COVID-19 pandemic, specifically in relation to their (a) supports and (b) feelings of empowerment related to their child. Participants were 37 parents of children with disabilities who had extensive support needs and complex communication needs, with most families having a child with either autism or Down syndrome. Interviews were conducted with each family at three time points during the 2020–2021 school year. Results indicated that the supports families received varied widely, as did their feelings of empowerment— including empowerment related to advocacy and to supporting their child’s learning and well-being at home. The supports that families received from providers (e.g., teachers, service providers) impacted their feelings of empowerment, sometimes acting as facilitators and sometimes as barriers. Implications for future research and practice are discussed related to how teachers and other providers might better partner with families during crises like the COVID-19 pandemic and beyond.
Hybrid nanofluid flow over a slippery surface for thermal exploration
Authors: Alnahdi Abeer S. , Gul Taza
Published: August 2023

The potential of hybrid nanofluid (HNF) to maximize heat transportation has captured the attention of many researchers, inspiring them to further investigate the performance of the common base fluid. Conventional flow in Cu-Al2O3/H2O hybrid nanofluid (HNF) toward a high permeability horizontal flat plate incorporated in Darcy porous medium has been explored in this research to determine how Cu-Al2O3/H2O hybrid fluid will respond thermodynamically when physical factors like suction/injection and slip boundary conditions are present. In addition, the effects of radiation, dissipations, energy engagement, and inclined magnetized field associated with the fluid flow were studied. The governing system is transformed by similarity transformations to a solvable ordinary differential equation by employing HAM (Homotopy Analysis Method) scheme. The main results show that Cu-Al2O3/H2O has high thermal conductivity compared to Cu/H2O. As a result, hybrid fluids are essential for the development of thermal phenomena.
Psoas muscle analysis as a surrogate marker of sarcopenia and frailty: A multicenter analysis of predictive capacities over short- and long-term outcomes after abdominal aortic aneurysm repair
Authors: Vázquez Pérez Rocío , Álvarez Marcos Francisco , Tello Díaz Cristina , Bellmunt Montoya Sergi , Fernández-Samos Gutiérrez Rafael , Gil Sala Daniel
Published: August 2023

Objectives

Several predictive models exist for estimating the postoperative risks of abdominal aortic aneurysm (AAA) repair, although no particular tool has seen widespread use. We present the results of a multicenter, historic cohort study comparing the predictive capacity of the psoas muscle area (PMA), radiodensity (PMD), and lean muscle area (LMA) as surrogate markers of sarcopenia, over short- and long-term outcomes after AAA repair, compared to the mFI-5 and American Society of Anesthesiologists (ASA) scales.

Methods

Retrospective review was conducted of all consecutive AAA elective repair cases (open or endovascular) in three tertiary-care centers from 2014 to 2019. Cross-sectional PMA, PMD, and LMA at the mid-body of the L3 vertebra were measured by two independent operators in the preoperative computed tomography. Receiver operating characteristic (ROC) curves were used to determine optimal cutoff values. Bivariate analysis, logistic regression, and Cox’s proportional hazards models were built to examine the relationship between baseline variables and postoperative mortality, long-term mortality, and complications.

Results

596 patients were included (mean age 72.7 ± 8 years, 95.1% male, 66.9% EVAR). Perioperative mortality was 2.3% (EVAR 1.2% vs open repair 4.6%, p = .015), and no independent predictors could be identified in the multivariate analysis. Conversely, an age over 74 years old (OR 1.84 95%CI 1.25–2.70), previous heart diseases (OR 1.62 95%CI 1.13–2.32), diabetes mellitus (OR 1.61 95%CI 1.13–2.32), and a PMD value over 66 HU (OR 0.58 95%CI 0.39–0.84) acted as independent predictors of long-term mortality in the Cox’s proportional hazards model. Heart diseases (congestive heart failure or coronary artery disease), serum creatinine levels over 1.05 mg/dL, and an aneurysm diameter over 60 mm were independent predictors of major complications.

Conclusion

Surrogate markers of sarcopenia had a poor predictive profile for postoperative mortality after AAA repair in our sample. However, PMD stood out as an independent predictor of long-term mortality. This finding can guide future research and should be confirmed in larger datasets.
Local anaesthetic systemic toxicity complicating intraoperative intercostal nerve blocks: What do clinicians need to know to prevent similar occurrence?
Authors: Basta Mafdy N
Published: August 2023

Local anaesthetic systemic toxicity is a life-threatening adverse event that may occur after administration of local anaesthetics through a variety of routes. Local anaesthetic systemic toxicity is always a potential complication and may occur with all local anaesthetics and in any route of administration. Local anaesthetic systemic toxicity primarily affects the central nervous system and the cardiovascular system and may be fatal. The following is a case of local anaesthetic systemic toxicity complicating surgeon-performed intraoperative intercostal nerve blocks at multiple levels, with a mixture of liposomal bupivacaine and bupivacaine hydrochloride in a patient who underwent video-assisted segmental lung resection for lung cancer under general anaesthesia. Local anaesthetic systemic toxicity presented with seizures and hypotension. The patient was successfully managed and fully recovered. This case illustrates the importance of awareness regarding the prevention, diagnosis and treatment of local anaesthetic systemic toxicity among medical professionals who administer local anaesthetics.
Influence of a Concurrent Exercise Training Program on Health-Related Quality of Life During Advanced Pregnancy: The GESTAFIT Project
Authors: Marín-Jiménez Nuria , Baena-García Laura , Coll-Risco Irene , Flor-Alemany Marta , Castro-Piñero José , Aparicio Virginia A.
Published: August 2023

Background:

Health-related quality of life (HRQoL) may be altered during pregnancy due to pregnancy-related changes in all domains of women’s health.

Hypothesis:

A supervised concurrent exercise-training program from the 17th gestational week until birth positively influences HRQoL.

Study Design:

Randomized controlled trial.

Level of Evidence:

Level 1.

Methods:

Eighty-six pregnant women (age, 33.1 ± 4.6 years; prepregnancy body mass index, 23.5 kg/m2), divided into exercise (n = 41) and control (n = 45) groups, participated in this study (per-protocol basis). The exercise group followed a 60-min, 3 days/week, concurrent (aerobic + resistance) exercise training program. HRQoL was assessed with the 36-Item Short Form Health Survey (SF-36), where higher scores (0-100) indicate better HRQoL.

Results:

After adjusting for potential confounders, the exercise group decreased 16.1 points less than the control group in the SF-36 physical functioning domain [between-group differences (B): 95% confidence interval (CI), 9.02 to 23.22; P < 0.01], and 4.5 points less in the SF-36 physical component summary than the control group (between-group differences (B): 95% CI, 0.65 to 8.28; P = 0.02). Intention-to-treat basis analyses depicted similar results, where the exercise group decreased 10.03 points less than the control group the in the SF-36 social functioning domain (between-group differences (B): 95% CI, 0.39 to 19.68; P = 0.04).

Conclusion:

A supervised concurrent exercise training program ameliorates HRQoL decreases along gestation. Although HRQoL decreased throughout pregnancy in both groups, this impact was less in the exercise group, especially in the SF-36 physical functioning, the SF-36 social functioning, and the SF-36 physical component summary.

Clinical Relevance:

Healthcare providers may encourage pregnant women to exercise in this physiological stage for a better HRQoL throughout pregnancy.

ClinicalTrials.gov Identifier:

NCT02582567; Date of registration: 20/10/2015
The poet of LA's urban: Mike Davis
Authors: Storper Michael
Published: August 2023

Mike Davis's relationship to urban studies involved a combination of positivist analysis, history, and poetics. His contribution to the City of Quartz is assessed from this triple perspective. His role as the poet of LA's anguishing and complex nature takes its place alongside more conventional academic scholars, filmmakers, musicians, and artists. His contribution to urban social science in general, and to LA studies in particular, will be enduring.
Does the External Pericardial Lateral Tunnel Fontan Pathway Enlarge to Accommodate Somatic Growth? A Preliminary Analysis
Authors: Rahm Amy L. , Razzouk Jacob A. , Foster Carter S. , Voleti Sonia L. , Razzouk Anees J. , Fortuna Randall S.
Published: August 2023

Objectives: An ideal Fontan pathway should be capable of adapting to changes in circulatory demands. The external pericardial lateral tunnel Fontan (EPLTF) is constructed of viable, autologous tissue and may be capable of changing in size. We investigated the ability of the EPLTF to enlarge with increasing physiologic demands of somatic growth. Methods: Retrospective review of echocardiographic images for patients with a minimum of five years follow-up after EPLTF. Serial echocardiographic measurements of the EPLTF pathway were obtained at three distinct locations: the inferior vena cava junction with the EPLTF, midsection of the EPLTF, and cross-sectional area of the EPLTF visualized in a four-chamber view. Body surface area (BSA) was calculated at the time of each echocardiographic measurement. Changes in echocardiographic measurements over time were analyzed and compared with changes in BSA. Results: A total of 332 echocardiographic studies from 38 patients were reviewed. Significant enlargement of the EPLTF pathway is observed at the inferior vena caval junction ( P < .001), midsection ( P < .01), and cross-sectional area ( P < .001). Repeated measures correlation between pathway measurements and BSA is highly significant ( P < .001). Conclusions: The EPLTF pathway enlarges over time in correlation with increasing BSA. Further research is needed to define ideal pathway size, differentiate normal physiologic growth from pathologic enlargement, and correlate changes with clinical outcomes.
Paper 05: Inferior Hill-Sachs Position Predicts Failure Following Primary Bankart Repair for On-Track Lesions
Authors: Fox Michael , Fatora Gabrielle , Reddy Rajiv , Barrow Aaron , Charles Shaquille , Lesniak Bryson , Rodosky Mark , Hughes Jonathan , Popchak Adam , Lin Albert , Cong Ting
Published: August 2023

Objectives:

The on-track/off-track concept for shoulder instability primarily describes the medial-lateral rotational relationship between an engaging Hill-Sachs lesion and a Bankart defect. Though clinically more protective, on-track lesions retain some risk for failure following primary arthroscopic Bankart repair. While some of this risk can be explained by the “near-track” concept, the role of the superior-inferior position of the Hill-Sachs lesion has never been studied in the context of failure of primary Bankart repair. This study aims to identify the relationship between the superior-inferior position of a Hill-Sachs lesion and risk for failure following primary arthroscopic bankart repair. Our hypothesis is that inferiorly-based Hill-Sachs lesions may engage with the arm in neutral and thus be higher risk for failure following primary Bankart repair.

Methods:

We performed a retrospective analysis of 201 individuals with on track lesions who underwent primary arthroscopic Bankart repair (without remplissage) between 2007 and 2019 who have minimum 2 year follow-up. Patients with failure were defined as those who sustained a dislocation or subluxation after the index procedure. A pre-operative sagittal MRI cut showing the maximum Hill-Sachs diameter was used for position analysis. Sagittal position of the Hill-Sachs was defined the angle formed by the Hill-Sachs bisecting line through the humeral head center, against the mid-humeral axis on a sagittal MRI cut (Figure 1); for example, an angle of 0 is twelve o’clock on the humeral head, while an angle of 90 is equatorial. We defined a priori four Hill-Sachs quadrants for semi-quantitative analysis, based on physiologic arm positions: Superior (angle < 40), Mid-Superior (40-60), Mid (61-90), and Inferior (>90). Hill-Sachs quadrants were then correlated against failure following primary arthroscopic Bankart repair.

Results:

Failure rates following arthroscopic bankart repair as it relates to superior-inferior position of the Hill-Sachs lesion is as follows (Table 1): No Hill-Sachs (10 of 73, 13.7%), Superior (0 of 7, 0%), mid-superior (6 of 36, 16.7%), Mid (19 of 71, 26.8%), and Inferior (1 of 6, 16.7%). We grouped Hill-Sachs lesions into low grade (No Hill-Sachs, Superior, and Mid-Superior quadrants) and high grade (Mid and Inferior quadrants). Low grade represented a 13.8% risk of failure, while High grade represented a 26% risk for failure (p=0.034).

Conclusions:

The superior-inferior sagittal position of a Hill-Sachs lesion may contribute to risk for failure of primary arthroscopic Bankart repair for on-track lesions. Inferiorly-based Hill-Sachs lesions may risk engagement at lower degrees of arm abduction, and in our study represent nearly double the risk of failure of arthroscopic Bankart repair as compared to superior Hill-Sachs positions. [Table: see text]
Paper 15: 5 Year Radiographic and Functional Outcomes of Non-Operative Treatment of Completely Displaced Clavicle Fractures in Teenagers, A Prospective Study
Authors: Edmonds Eric , Bastrom Tracey , Heyworth Benton , Pennock Andrew , Polinsky Samuel
Published: August 2023

Objectives:

Optimal treatment for displaced clavicle fractures in adolescents remains controversial, with many surgeons favoring operative reduction and fixation. To prospectively assess patient reported outcomes (PROs) in teenagers undergoing non-operative treatment of a completely displaced clavicle fracture ≥ 5 years post-injury. Furthermore, bilateral clavicle imaging was used to determine the association between these outcomes and the presence or absence of bony remodeling.

Methods:

This study used a subset of patients previously enrolled in a multicenter study looking at adolescent clavicle fractures. Patients from a single institution and ≥ 13 years at the time of injury, with non-operatively treated completely displaced clavicle fractures who were ≥5 years out from their initial injury were able to participate in the study. Patients were clinically evaluated for evidence of scapular dyskinesia, strength deficits, and cosmetic concerns. Bilateral clavicle imaging was used to assess residual shortening, displacement, and angulation. PROs included: ASES, QuickDASH, Marx Shoulder Activity Scale, and return to sport data.

Results:

Twenty-four patients were available for follow-up, of whom 17 (71%) consented to the additional imaging. The mean age at the time of injury was 14.5±1.1 years with 89% being male. At a mean follow-up of 6.1 years, all fractures healed and no interventions were necessary (Figure 1). Significant remodeling was observed across all measurements with improvements of 70% in mean shortening (22.8 mm to 6.8 mm, p<0.001), 73% in superior displacement (13.4 mm to 3.6 mm, p<0.001), and 83% in angulation (10.4˚ to 1.8˚, p<0.001) (Figure 2). Thirteen patients (72%) had initial shortening > 2 cm and all remodeled to < 2 cm. PROs were almost universally excellent with no patients reporting shoulder pain and mean ASES, quickDASH, and Marx activity scores of99±3, 1±3, and 20±1, respectively, with 79% of patients reporting perfect scores in all 3 domains. Majority (58%) were completely satisfied with the appearance of their shoulder, 38% were more satisfied than not, one patient (4%) was neither satisfied nor dissatisfied, and no patients were dissatisfied. All patients except 1 returned to sporting activities if interested. No PROs were associated with bony remodeling (p>0.05).

Conclusions:

Teenage patients with completely displaced clavicle fractures can expect excellent radiographic and clinical outcomes 5 years post-injury if treated non-operatively. This study further supports the role of non-operative treatment for teenagers, with nearly perfect outcomes reported bringing into question the role of acute operative management of these fractures given its associated risks and costs.
Paper 44: Deep Learning Artificial Intelligence Tool for Automated Radiographic Determination of Posterior Tibial Slope in Patients with Anterior Cruciate Ligament Injuries
Authors: Lu Yining , Camp Christopher
Published: August 2023

Objectives:

An increased posterior tibial slope (PTS) corresponds with an increased risk of graft failure following anterior cruciate ligament reconstruction (ACLR). Validated methods of human PTS measurements are subject to interobserver variability and can be inefficient on large-scale sets of images. The purpose of this study is to develop a deep learning artificial intelligence technique for the automated measurement of PTS from standard lateral knee radiographs.

Methods:

A deep learning U-Net model was developed on a cohort of 300 postoperative short leg lateral radiographs from ACLR patients to segment the tibial shaft, tibial joint surface, and tibial tuberosity. The model was trained via a random split following an 80:20 train-validation scheme. Masks for training images were manually segmented and the model was trained for 400 epochs. An image processing pipeline was then deployed to annotate and measure the PTS using the predicted segmentation masks. Finally, the performance of this combined pipeline was compared to human measurements performed by two study personnel using a previously validated manual technique for measuring PTS on short leg lateral radiographs on an independent test-set consisting of both preoperative and postoperative images.

Results:

The U-Net semantic segmentation model achieved a mean Dice similarity coefficient of 0.885 on the validation cohort. The mean difference between human-made and computer-vision measurements was 1.92⁰ (σ = 2.81⁰, P=0.24). Extreme disagreements between human and machine measurements as defined by differences ≥5⁰ occurred less than 5% of the time. The model was incorporated into a web based digital application for demonstration purposes which can provide measurement of an uploaded image in portable network graphics format in less than 5 seconds.

Conclusions:

We developed an accurate and reliable deep learning computer vision algorithm to automate the measurement of PTS on lateral knee radiographs. This tool will be deployed for clinical use on an institution-wide basis and, pending external validation, be made available to outside orthopaedic surgeons. This will provide an efficient and accurate tool to measure PTS during the preoperative assessment of ACL-injured patients.
Paper 63: Return to Long Distance Running After Hip Arthroscopy for Femoroacetabular Impingement
Authors: Olsen Reena , Burger Joost , Dooley Matthew , Coleman Struan , Ranawat Anil , Kelly Bryan , Nawabi Danyal , Marom Niv
Published: August 2023

Objectives:

Arthroscopic hip surgery for femoroacetabular impingement (FAI) has shown high rates of return to different sports in athletes. No studies to date have focused on patients’ return to long- distance running, a running sport with unique characteristics and demands. The purpose of this study was to determine return to long-distance running rates and changes in running performance in long distance runners undergoing hip arthroscopic surgery for the treatment of FAI and to identify possible risk factors associated with not returning to long distance running.

Methods:

An institutional hip preservation registry was retrospectively reviewed for patients identified as long distance runners (half marathons and marathons) who underwent primary hip arthroscopies for FAI performed between March 2010 and January 2017. Patient demographics and injury characteristics as well as clinical and radiographic findings were recorded. All patients were contacted for return to running information using a running specific return to sport questionnaire. Multivariable logistic regression analysis was used to identify potential risk factors for not returning to long-distance running.

Results:

Sixty-eight long distance runners (78 hips) were included. Mean patient age and body mass index (BMI) were 37.8±8.9 years and 23.8±3.3 kg/m2, respectively. Thirty-eight (56%) were female runners. Mean weekly running milage prior to injury was 34.5±16.9 miles. Mean duration of hip symptoms prior to seeking medical evaluation was 77.3±16.9 weeks. Fifty-nine runners (87%) had to stop or modify their running for a mean duration of 44.3±45 weeks prior to surgery due to hip symptoms. Overall, 50 runners (74%) returned to any running, of which 25 runners (50%) returned to long distance running completing half/full marathons races after surgery. Most common reasons for not returning to running were pain or discomfort (50%) followed by fear of re-injury (22%) and additional different injuries (22%). Among runners who did not return to any running, 12 (67%) reported satisfaction from surgery. Multivariable logistic regression analysis revealed female runners (odds ratio [OR]=0.2; confidence interval [CI]=0.0 to 0.9; p=0.034) and hips with radiologic findings of higher alpha angles (OR=0.9; 95% CI=0.9 to 1.0; p=0.045) were less likely to return to long distance running.

Conclusions:

Hip arthroscopic treatment for FAI in symptomatic long-distance runners, a distinctive subgroup of runners, allowed most of them (74%) to return to running, however only 40% returned to long distance running races. Female runners and runners with radiologic findings of higher alpha angles were less likely to return to long-distance running. These data can better guide clinicians and long- distance runners with realistic expectations related to the arthroscopic management of symptomatic FAI.
Poster 129: Biomechanical Evaluation of the Isometry of Medial Patellofemoral Ligament Reconstruction Grafts Fixed at Non-Anatomic Femoral Insertion Points
Authors: Gupta Andrew , Mortensen Alex , Illing Damian , Guss Andrew , Herrick Jennifer , Presson Angela , Burks Robert , Aoki Stephen , Rosenthal Reece
Published: August 2023

Objectives:

In MPFL reconstruction surgery, achieving perfect placement of the femoral tunnel intraoperatively is difficult. An understanding of the effects femoral tunnel malpositioning has on graft isometry is crucial to minimizing instability or overconstraint which leads to anterior knee pain, increased patellofemoral contact pressures, or graft failure. The purpose of this study was to identify differences in MPFL reconstruction graft isometry with femoral tunnel malpositioning, specifically evaluating isometry differences as the femoral position is moved anterior, posterior, proximal, and distal relative to the femoral radiographic landmark of the MPFL, Schottle’s point.

Methods:

A biomechanical study evaluating 11 fresh frozen cadaveric knees was conducted. Non-elastic suture, used as an MPFL graft analogue, was anchored at Schottle’s point with the knee at 30° of flexion, and at 5 mm and 10 mm anterior, posterior, superior, and distal to Schottle’s point. A draw wire displacement sensor was used to evaluate length changes of the MPFL graft analogue through 0-120° of knee flexion. Knee flexion position was continuously measured using a motion tracking system. Pairwise t-tests with Bonferroni corrections were used to compare isometry between Schottle’s point and non- anatomic femoral insertion points.

Results:

Grafts placed at Schottle’s point demonstrated mild anisometry with tightening in extension and loosening in flexion. Similarly, grafts placed distally and posteriorly also demonstrated tightening in extension and loosening in flexion. Grafts placed anteriorly and proximally demonstrated tightening in flexion. Mean and range of total draw wire excursion over full ROM across specimens is shown in Figure 1. The mean draw wire length was found to be greater with further displacement from Schottle’s point in all directions but posterior. Pairwise comparisons relative to Schottle’s point found grafts placed in the proximal or distal direction demonstrated significant differences in MPFL excursion, while grafts placed in the anterior or posterior direction did not (10 mm proximal: 0.36 (p=0.028), 5 mm distal: 0.14 (p=0.012), 10 mm distal: 0.22 (p<0.001)) (Table 1).

Conclusions:

In order to minimize the risk of graft tightening during knee flexion, if deviating from Schottle’s point, it is safest to err posterior or distal in femoral tunnel position. Travel away from Schottle’s point in the proximal or distal direction has the greatest effects on graft isometry. The greatest risk of overconstraint and graft tightening in flexion is seen with proximal placement of the femoral insertion point.
Poster 135: Posterior Capsular Release for Knee Extension Deficits After Anterior Cruciate Ligament Reconstruction in Athletes
Authors: Iturregui Jose , Vij Neeraj , Tummala Sai , McQuivey Kade , Economopoulos Kostas , Brinkman Joseph
Published: August 2023

Objectives:

To describe outcomes of posterior capsular release to treat knee extension deficits after anterior cruciate ligament (ACL) reconstruction in athletes.

Methods:

A retrospective review was performed between January 2014 and December 2019 for patients undergoing arthroscopic posterior capsular release for knee extension loss following ACL reconstruction. Patients were indicated for the procedure if they had greater than 10° of extension loss at least three months after ACL reconstruction that was refractory to physical therapy. Patients were included in the study if they were involved in either high school or college athletics, had complete outcomes of interest, and had at least two years of follow up. Collected outcomes included preoperative and postoperative measurement of knee extension, international knee documentation committee (IKDC) score, Lysholm score, return to sport data, and complications.

Results:

Over the study period a total of 38 arthroscopic posterior capsular releases were performed. Of these, 20 were high school or college athletes. Two of these patients did not have 2-year follow up, leaving a total of 18 patients included in the analysis. Patients underwent surgery at an average of 16 weeks after ACL reconstruction. Knee extension improved an average of 13.8° at 2-years follow up (pre- release extension deficit 15.1°, post-release extension deficit 1.3°, p < 0.005). Improvements in the IKDC score averaged 21.7 at 6 months and 35.0 at 24 months, both of which were statistically significant (p < 0.001). Similarly, differences in Lysholm included a significant improvement of 23.0 and 34.2 at 6 months and 2 years, respectively (p < 0.001). In total, 77.8% returned to sport at an average of 9.8 months from their primary surgery and 6.5 months following posterior capsular release surgery. Complications included one patient that required revision capsular release for persistent extension loss, one ACL tear of the ipsilateral knee, and two ACL tears of the contralateral knee. No infections or neurovascular injuries occurred.

Conclusions:

Knee extension loss after ligamentous repair surgery can have significant consequences including diminished patient satisfaction, reduced return to sport, and an increased risk of osteoarthritis development. Although arthroscopic posterior capsular release is a recognized treatment for knee extension loss, outcomes have not been reported in athletes. In our series, arthroscopic posterior capsular release resulted in significant improvement of knee extension and patient reported outcome scores at 6 month and 2 years postoperatively. Additionally, the procedure appears to be safe with few complications and only 5.6% of patients requiring repeat arthroscopy for knee extension loss. Posterior capsular release appears to be a reliable and safe treatment for athletes with persistent knee extension loss after ACL reconstruction.
Poster 138: Intra-articular Femorotibial Rotation is Associated with Tibial Tubercle-Trochlear Groove Distance
Authors: Pascual-Leone Nicolas , Jahandar Amir , Davie Ryann , Bram Joshua , Chipman Danielle , Imhauser Carl , Green Daniel
Published: August 2023

Objectives:

A tibial tubercle-trochlear groove (TT-TG) distance of 20 mm is typically used when determining whether tibial tubercle anteromedialization (AMZ) is needed for patellar instability. TT-TG distance, however, may depend on the internal/external (IE) rotation of the tibia in relation to the femur, which is typically not controlled for. Without knowledge of the variability in an individual’s TT-TG influenced by femorotibial rotation, the use of a specific TT-TG distance during pre-operative planning for patellar instability may lead to incorrect decisions on the use of tibial tubercle AMZ. We hypothesized that knee joint IE rotation is related to the TT-TG distance.

Methods:

A total of 8 independent human cadaveric knee specimens (age: 32±6; 4 males, 4 females) were utilized. A robotic manipulator (ZX165U, Kawasaki Robotics, Wixom, MI, USA) instrumented with a universal force/moment sensor was used to determine knee joint internal/external (IE) rotation under applied moments of ±5Nm at full extension. Two independent reviewers selected the trochlear groove and tibial tuberosity points on CT images of each specimen to define TT-TG (ICC=0.969). To determine the influence of knee joint IE rotation on TT-TG, 3D models generated from CT scans were registered to tibiofemoral kinematics. Subsequently, linear regression was performed to determine the relationship between knee joint IE rotation and TT-TG. Regression coefficient and standard error of measurement (α=0.05), and coefficient of determination (r2) were reported.

Results:

Knee joint IE rotation averaged 23.0 ± 4.2°. TT-TG changed by 12.1 ± 2.8 mm over this range. For every degree of knee joint IE rotation, TT-TG changed by 0.52 ± 0.07 mm (p<0.001 and r2>0.987). At neutral rotation, the TT-TG averaged 14.21 ± 5.0 mm.

Conclusions:

TT-TG was highly dependent on knee joint IE rotation changing by 0.52 mm for every degree of knee joint IE rotation. Thus, an offset in IE rotation of 10° would lead to a change in TT-TG of 5.2 mm, enough to alter surgical decision making for or against tibial tubercle AMZ. Physicians should pay close attention to knee joint IE rotation when measuring TT-TG in their patients, specifically in patients found to have a TT-TG near 20 mm, a key indication for surgical treatment of patellar instability. [Table: see text][Table: see text]
Poster 141: Does the Traditional TT-TG Distance Accurately Reflect the Relative Position of the Tibial Tubercle to the Trochlear Groove? A Three-Dimensional Analysis
Authors: Dandu Navya , Elias Tristan , Hevesi Mario , Credille Kevin , Wang Zachary , Haneberg Erik , Inoue Nozomu , Yanke Adam
Published: August 2023

Objectives:

The tibial tubercle to trochlear groove (TT-TG) distance often guides surgical decision- making for patellar instability. Traditional TT-TG measurements are limited by interrater reliability and lack of consideration for variable anatomy throughout flexion. The purpose of this study was to compare the traditional TT-TG measurement to three-dimensional measures generated from automated trochlear groove detection with sequential radial slices on magnetic resonance imaging (MRI).

Methods:

Twenty-four knees (4 healthy controls, 20 patellar instability patients) were segmented into three-dimensional distal femur and tibia models. A custom-designed program was employed to detect the trochlear groove through its course based on the shortest distance to the origin in a polar (radial) axis defined by the distal femoral condyles. The program also identified the surface projection of the tibial tubercle center of mass. The medial-lateral distance between the trochlear groove and tibial tubercle was calculated for the first 45 degrees of the detected groove to generate radial TT-TG (rTT-TG) values. The mean and maximum rTT-TG values were compared to the traditional TT-TG MRI measurement performed by one grader.

Results:

Mean rTT-TG values were significantly greater than traditional measurements (21.8 mm versus 17.9 mm, p=.003) with moderate correlation between measurements (Pearson r = 0.59, p=.002). In Dejour C and D dysplasia, the mean rTT-TG measurements trended towards being greater than traditional measurements (C: 24.3 mm versus 16.6 mm; D: 28.5 mm versus 21.8 mm; p=0.057 for both comparisons). Dejour C dysplasia demonstrated a significantly greater maximum rTT-TG than the traditional measurement (27.9 mm versus 16.6 mm, p=0.029), and Dejour D dysplasia demonstrated a similar trend (30.2 mm versus 21.8 mm; p=0.057).

Conclusions:

Traditional TT-TG distances may underestimate the true medial-lateral offset between trochlear groove and tibial tubercle, particularly in patients with high- grade dysplasia. This represents a potential alternative to the current standard measurement techniques which may improve measurement reliability by automation. Our study suggests that utilizing 3D radial TT-TG values via automated measurement may more accurately portray the variable anatomy of the trochlear entrance and offer a standardized alternative to a frequently used measurement to overcome reader reliability.
Poster 182: Acromial Morphology Influences Instability Risk and Direction: An MRI Study
Authors: Nolte Philip , Ruzbarsky Joseph , Provencher Matthew , Bradley James , Millett Peter , Arner Justin
Published: August 2023

Objectives:

To determine if acromial morphology is associated with posterior or anterior shoulder instability as measured on MRI.

Methods:

MRI measurements of posterior acromial coverage (PAC), posterior acromial height (PAH), posterior acromial tilt (PAT), and anterior acromial coverage (AAC) were completed for three separate matched groups who underwent surgical intervention: posterior instability, anterior instability, and a comparison group of patients with who underwent arthroscopic surgery for snapping scapula. Inclusion criteria were patients with recurrent instability younger than 40 years of age without multidirectional instability, glenoid bone loss greater than 13.5% or glenoid retroversion greater than 10%.

Results:

Thirty-seven patients were included in each group. PAC was significantly less in the posterior instability group when compared to anterior and the comparison groups (68.3° vs. 88.7° vs. 81.7°, p<.001). PAH was significantly greater in the posterior group than compared to the anterior instability patients (11.0 mm vs -0.1 mm, p<.001) as well as the comparison patients (0.7 mm, p<.001). There was no difference between the posterior and anterior groups in terms of PAT or AAC (p=0.45, p=0.05). PAT was significantly smaller in the posterior instability group than the comparison group (55.2 degrees vs 62.2 degrees, p=0.026). The anterior and comparison groups were not significantly different in PAH or PAT (p=8.74, p=0.067) but were significantly different with AAC (p=0.26).

Conclusions:

The posterior acromion is significantly higher and flatter in patients with posterior shoulder instability who require arthroscopic capsulolabral repair when measured on pre-operative MRI. This information may help clinicians to both diagnose and predict the need for operative intervention for patients with posterior labral tears.
Poster 201: Trends and Projections in Surgical Stabilization of Glenohumeral Instability in the United States from 2009 to 2030: Rise of the Latarjet and Fall of the Open Bankart
Authors: Gabig Andrew , Karzon Anthony , Cooke Hayden , Graf Alexander , Gottschalk Michael , Wagner Eric
Published: August 2023

Objectives:

Advances in surgical techniques have improved the ability to addressrecurrent glenohumeral instability via arthroscopic capsulolabral repair and bonerestoring procedures such as Latarjet. Given the paucity of studies analyzing temporaltrends in surgical management of glenohumeral instability, the purpose of this studywas to assess trends in treatment of anterior, posterior, and multidirectional instabilityover a 10-year period and model projections to 2030.

Methods:

Using IBM Watson Marketscan national database, all patients thatunderwent glenohumeral instability procedures from 2009 to 2018 were identified.Procedures were identified using common procedural terminology (CPT) codes foropen Bankart Repair, Latarjet, anterior bone block, posterior bone block,multidirectional capsular shift, and arthroscopic Bankart procedures. Sample weightsprovided by the database were utilized to calculate national estimates. The UnitedStates (U.S.) Census Bureau annual population data were utilized for calculatingincidence. Future projections to 2030 were modeled using Poisson and linearregression.

Results:

There were an estimated 446,072 glenohumeral instability cases from 2009-2018. Per capita (per 100,000) incidence remained constant, from 14.8 in 2009 to 14.5in 2018. Arthroscopic Bankart comprised the highest number of procedures throughoutthe study period, accounting for 89% of all procedures in 2009 and 93% in 2018. OpenBankart procedures decreased by 65% from 2009 to 2018, while there was a 250%increase in Latarjet procedures over the same period. Patient demographics did notchange over the study period, and males aged 18-25 comprised the largestdemographic group undergoing anterior instability procedures. Multidirectionalinstability procedures exhibited the least pronounced gender differences. Futuremodeling from 2018-2030 projected continued steady rise in arthroscopic Bankart(40,000-49,000 case/yr), rapid growth in Latarjet (1370-4300 cases/yr), and continueddecline in open Bankart (1000-250 cases/yr) procedures.

Conclusions:

Arthroscopic Bankart continues to be the most common glenohumeralinstability procedure in the U.S. From 2009 to 2018, incidence of open Bankartprocedures declined while Latarjet procedures markedly increased. Future projectionsto 2030 mirrored these findings. These data may provide an enhanced understandingof the evolution of surgical treatment of glenohumeral instability within the U.S. layingthe foundation for continued prospective studies into the appropriate indications andadvancements in surgical techniques. [Table: see text][Table: see text]
Poster 229: Expectations for Return to Sport Before and After Hip Arthroscopy with Minimum 1-year Follow-Up
Authors: Li Zachary , Triana Jairo , Mojica Edward , Blaeser Anna , Shankar Dhruv , Akpinar Berkcan , Lin Lawrence , Youm Thomas , buldo-licciardi michael
Published: August 2023

Objectives:

Setting appropriate expectations for orthopedic surgery functional outcomes can contribute to postoperative motivation and satisfaction. For hip arthroscopy, the literature is limited regarding patients’ expectations for returning to sport. This study aims to compare preoperative expectations with postoperative return-to-sport status in patients who underwent primary hip arthroscopy.

Methods:

We conducted a prospective cohort study of patients who underwent primary hip arthroscopy. Return to sport expectations were recorded preoperatively. Return to preinjury sport status was assessed along with updated sport expectations at a minimum of 1 year follow-up after surgery (range 1.1 to 2.6 years; mean 2.0 years). The proportion of patients who expected to return was compared to actual return rates.

Results:

Thirty-five patients who underwent hip arthroscopy were prospectively recruited. Preoperatively, 31 patients (88.6%) expected to return to their preinjury sport level, while only 16 (45.7%) actually returned to that level. 34 (97.1%) expected to return to their main sport and 22 (62.9%) actually returned. 9/35 returned to their preinjury primary sport at a lower level. 10/35 patients had completely given up their original sport by time of follow-up. All 11 patients who reported a change in their primary sport chose a lower impact sport, transitioning from tennis, running, kickboxing, frisbee, volleyball to cycling, pilates, walking, and yoga. Logistical regression found no significant difference between expectations and return to sport level when controlling for age, BMI, gender.

Conclusions:

This study found a significant difference between preinjury return-to-sport expectations and actual return rates following hip surgery. Although patients had high expectations for recovery, a majority did not return to their preinjury sport level and a high portion did not return at all. All patients that took up a different sport went from one of high impact to low impact. These data can provide more realistic return-to-sport expectations for patients undergoing hip arthroscopy.
Poster 243: TT-TG Measurements Obtained in Weight Bearing and Non-Weight Bearing States are Different- Positioning in CT Scan Affects Treatment Selection
Authors: Cirrincione Peter , Price Payton
Published: August 2023

Objectives:

There are multiple aspects of lower extremity alignment that can contribute to patellar instability. Physicians regularly consider TT-TG distance when planning treatment for patients with patellar instability. TT-TG has been classically measured on non-weight bearing magnetic resonance imaging (MRI) or computed topography (CT) scans, but more recently clinicians have been obtaining these measurements on weight bearing CT scans. Literature has not previously compared TT-TG measurements obtained in weight bearing and non-weight bearing positions. This study compares TT- TG measurements performed in weight-bearing vs. non-weight bearing positions of the same knees.

Methods:

The images of patients with patellar instability who obtained weight bearing and non-weight bearing CT scans between the dates of January 1st, 2014 and December 31st, 2021 were measured for TT-TG distance. A paired two sample t test for means was utilized to compare the measurements.

Results:

Thirty knees had both a weight bearing and non-weight bearing TT-TG length CT scan performed that could be used to measure TT-TG distance. The weight bearing group, with an average of 15.2 mm, was significantly greater than the non-weight bearing group, averaging 10.2 mm (p=<.0001). Additionally, the variance in measurements for knees under the weight bearing positions (37.6 mm) was more than twice as large as the variance for measurements obtained in the non-weight bearing position (16.5 mm).

Conclusions:

TT-TG distance is routinely used while diagnosing and planning treatment of patients with patellar instability. In this study, TT-TG distance was found to be significantly greater in the weight bearing position compared with the non-weight bearing position of the same knee. This fact is both critical to understand and useful in planning the appropriate instability procedure. Dynamic motion, rotation and axial loading play a role in patellar instability and need to be evaluated to arrive at the appropriate treatment algorithm.