Stand-alone Construct Research Articles

Customers’ perceptions and responses to hotels’ corporate social responsibility (CSR) orientation: the case of Bethlehem hotels, Palestine

ABSTRACT This study investigates customers’ perceptions of the notion of corporate social responsibility (CSR) and how such perceptions influence their consumption behavioural intentions and outcomes in the hospitality industry in Bethlehem, Palestine. The research study adopted a qualitative methodology using semi-structured interviews with fifteen tourists who stayed in Bethlehem hotels. This study reveals that customers view the different dimensions of CSR in their right and stand-alone constructs. Paradoxically, our study suggests that customer’s willingness to pay and loyalty were not influenced by understanding such a distinction as responsibilities. This study further reveals that the interaction between customers’ perceptions of CSR and contextual and situational factors such as trust, transparency and service quality can determine customer behavioural responses to the hotels’ CSR orientation. The study offers recommendations on practical measures that can be undertaken to influence and enhance customers’ responses to hotels’ CSR agenda. The paper finally ends by identifying the study’s limitations and avenues for further research.

1066 Comparative Outcome Using Expandable Versus Static Cage in Direct Lateral Interbody Fusion for Degenerative Lumbar Disc Disease

INTRODUCTION: Subsidence has been a common concern or complication in patients undergoing TLIF with an expandable cage or standalone DLIF with a static cage. It could lead to further complications such as pseudoarthrosis, lumbar kyphosis, and radiculopathy. Recently, expandable technology has emerged in lateral interbody fusion, which could be delivered through the smaller surgical corridors. Therefore we sought to determine the extent of radiological outcome and subsidence rate in patients with expandable cages. METHODS: A retrospective review of patients who underwent DLIF was performed. Only patients with degenerative lumbar disc disease were included. Baseline demographic and radiographic outcomes such as cage subsidence, anterior and posterior disc height, foraminal dimensions, and other spinopelvic parameters were collected. The primary endpoint was severe cage subsidence (grade 2 and 3) per level according to the classification by Marchi et al. Multivariate Analysis was performed. RESULTS: 59 patients underwent DLIF with expandable (n = 25) and static (n = 34) cages respectively. Both expandable and static groups have comparable baseline demographic such as age, gender, BMI, and medical comorbidities. The average follow-up period was 16 months. Both groups also had a comparable rate of the standalone construct (40% vs 68%, p 0.088). Significant higher cage width and length were used in the expandable group. However, there were no statistically significant differences in the restoration of both anterior and posterior disc heights, foraminal height, and central canal diameter. A significantly lower rate of severe subsidence was observed in the expandable group (4% vs 26.5%, p = 0.023) compared to the static group. CONCLUSIONS: In our study, expandable cages in DLIF patients were observed to have a significantly lower rate of subsidence when compared to those who received static cages.

Oncolytic Adenovirus Armed with a Novel Agonist of the CD137 Immune Checkpoint Stimulator Suppresses Tumor Growth.

Natural 4-1BBL (CD137L) is a cell membrane-bound protein critical to the expansion, effector function, and survival of CD8+ T cells. We reported the generation of an active soluble oligomeric construct, SA-4-1BBL, with demonstrated immunoprevention and immunotherapeutic efficacy in various mouse tumor models. Herein, we developed an oncolytic adenovirus (OAd) for the delivery and expression of SA-4-1BBL (OAdSA-4-1BBL) into solid tumors for immunotherapy. SA-4-1BBL protein expressed by this construct produced T-cell proliferation in vitro. OAdSA-4-1BBL decreased cell viability in two mouse lung cancer cell lines, TC-1 and CMT64, but not in the non-cancerous lung MM14.Lu cell line. OAdSA-4-1BBL induced programmed cell death types I and II (apoptosis and autophagy, respectively), and autophagy-mediated adenosine triphosphate (ATP) release was also detected. Intratumoral injection of OAdSA-4-1BBL efficiently expressed the SA-4-1BBL protein in the tumors, resulting in significant tumor suppression in a syngeneic subcutaneous TC-1 mouse lung cancer model. Tumor suppression was associated with a higher frequency of dendritic cells and an increased infiltration of cytotoxic CD8+ T and NK cells into the tumors. Our data suggest that OAdSA-4-1BBL may present an efficacious alternative therapeutic strategy against lung cancer as a standalone construct or in combination with other immunotherapeutic modalities, such as immune checkpoint inhibitors.

Three Biopolymers and Origin of Life Scenarios.

To track down the possible roots of life, various models for the initial living system composed of different combinations of the three extant biopolymers, RNA, DNA, and proteins, are presented. The suitability of each molecular set is assessed according to its ability to emerge autonomously, sustain, and evolve continuously towards life as we know it. The analysis incorporates current biological knowledge gained from high-resolution structural data and large sequence datasets, together with experimental results concerned with RNA replication and with the activity demonstrated by standalone constructs of the ribosomal Peptidyl Transferase Center region. The scrutiny excludes the DNA-protein combination and assigns negligible likelihood to the existence of an RNA-DNA world, as well as to an RNA world that contained a replicase made of RNA. It points to the precedence of an RNA-protein system, whose model of emergence suggests specific processes whereby a coded proto-ribosome ribozyme, specifically aminoacylated proto-tRNAs and a proto-polymerase enzyme, could have autonomously emerged, cross-catalyzing the formation of each other. This molecular set constitutes a feasible starting point for a continuous evolutionary path, proceeding via natural processes from the inanimate matter towards life as we know it.

Predicting Religious Undergraduates’ Career Development: The Salient Roles of Religious Calling, Life Satisfaction, and Quest Religiosity

Americans, over several decades, have consistently identified themselves as being religious and/or spiritual. Even though religious devotion has been recognized as a relevant diversity facet, therapeutic applications have been problematic. In the career development literature, numerous studies examined the influence of religion/spirituality (R/S) and generally categorized them in three ways. These include R/S as religious calling, as an integral feature of career interests and values, and as a supportive role. Yet, notable gaps exist among the articles. Researchers tended to operationalize R/S in a unidimensional manner, as a stand-alone construct instead of comprising multiple features. Investigations of religious calling in vocational matters were not recent. Further, few authors considered the influence of quest religious orientation on career development. In the present study, the relationships between seven career development and thirteen R/S variables using a sample of religious undergraduates (n = 290) enrolled in a career exploration course at a Christian university in the Midwest region of the United States were investigated. Findings from hierarchical regression analyses of vocational identity, career commitment, and career indecision checking for gender effects revealed three consistent salient predictors – religious calling, life-satisfaction, and quest religiosity. Implications of the results and possible therapeutic applications for career counselors are proposed.

Revisiting The Entrepreneurial Leadership Construct: A Multidimensional And Multilevel Perspective

This study aims to examine the evolution of the paradigm of entrepreneurial leadership as a standalone construct from its infancy to its current state. To do so, I conduct a comprehensive review of the literature on entrepreneurial leadership that encompasses definitional dissensus, measurement and methodological issues, and theory development. The findings are captured in the form of a multi-faceted and integrative model of entrepreneurial leadership and a set of propositions. The underlying perspective suggests that conceptualization of entrepreneurial leadership should draw from three areas—(a) entrepreneurship, (b) leadership, and (c) strategy—at multiple levels of analysis. This study contributes to research on entrepreneurial leadership by unifying divergent tenants and clarifying the current conceptual ambiguity surrounding the construct. Further, it advances the emerging paradigm of entrepreneurial leadership as a stand-alone construct, as opposed to an intersection of various areas of research. Finally, I identify research gaps and directions for future research. Keywords: Entrepreneurial Leadership, New Ventures, Opportunity Recognition, Resource Mobilization, Value Creation.

Scale Development and Validation of a Multi-dimensional Measure of Workplace Favoritism

Workplace favoritism research has been steady but limited for decades, yet a rigorously validated, comprehensive measure is not available to researchers. Furthermore, there continues to be concern among management scholars as to whether the concept is worthy of being examined as a stand-alone construct. A general consensus among management scholars is that favoritism is similar enough to organizational justice that it cannot provide additional explanatory value in employee emotional, attitudinal, or behavioral outcomes. This study challenges that ideology through the development and validation of a multi-dimensional workplace favoritism scale that can explain noticeably more variance in turnover intention than what organizational justice dimensions (i.e., procedural, distributive, interpersonal, and informational) can account for. Following Hinkin’s (1998) suggested approach to scale development and procedures used by Akremi and colleagues (Akremi, Gond, Swaen, Roeck, & Igalens, 2018), a five-phase scale development and confirmation process revealed three favoritism subdimensions including cronyism, nepotism, and a dimension related to an individual’s pleasantness and agreeableness. Results indicate that the sub-dimensional favoritism scales are valid and have predictive abilities that go beyond that of which can be accounted for by organizational justice measures.

Biomechanical analysis of stand-alone lumbar interbody cages versus 360° constructs: an in vitro and finite element investigation.

Low fusion rates and cage subsidence are limitations of lumbar fixation with stand-alone interbody cages. Various approaches to interbody cage placement exist, yet the need for supplemental posterior fixation is not clear from clinical studies. Therefore, as prospective clinical studies are lacking, a comparison of segmental kinematics, cage properties, and load sharing on vertebral endplates is needed. This laboratory investigation evaluates the mechanical stability and biomechanical properties of various interbody fixation techniques by performing cadaveric and finite element (FE) modeling studies. An in vitro experiment using 7 fresh-frozen human cadavers was designed to test intact spines with 1) stand-alone lateral interbody cage constructs (lateral interbody fusion, LIF) and 2) LIF supplemented with posterior pedicle screw-rod fixation (360° constructs). FE and kinematic data were used to validate a ligamentous FE model of the lumbopelvic spine. The validated model was then used to evaluate the stability of stand-alone LIF, transforaminal lumbar interbody fusion (TLIF), and anterior lumbar interbody fusion (ALIF) cages with and without supplemental posterior fixation at the L4-5 level. The FE models of intact and instrumented cases were subjected to a 400-N compressive preload followed by an 8-Nm bending moment to simulate physiological flexion, extension, bending, and axial rotation. Segmental kinematics and load sharing at the inferior endplate were compared. The FE kinematic predictions were consistent with cadaveric data. The range of motion (ROM) in LIF was significantly lower than intact spines for both stand-alone and 360° constructs. The calculated reduction in motion with respect to intact spines for stand-alone constructs ranged from 43% to 66% for TLIF, 67%-82% for LIF, and 69%-86% for ALIF in flexion, extension, lateral bending, and axial rotation. In flexion and extension, the maximum reduction in motion was 70% for ALIF versus 81% in LIF for stand-alone cases. When supplemented with posterior fixation, the corresponding reduction in ROM was 76%-87% for TLIF, 86%-91% for LIF, and 90%-92% for ALIF. The addition of posterior instrumentation resulted in a significant reduction in peak stress at the superior endplate of the inferior segment in all scenarios. Stand-alone ALIF and LIF cages are most effective in providing stability in lateral bending and axial rotation and less so in flexion and extension. Supplemental posterior instrumentation improves stability for all interbody techniques. Comparative clinical data are needed to further define the indications for stand-alone cages in lumbar fusion surgery.

An emic perspective on silence: Experiences of an adult Mexican migrant in the U.S. social setting

This qualitative case study explores the personal experience of Daniela, a Spanish-speaking adult immigrant from Mexico, who lived and worked in the United States, as she navigates her ways through an everyday social context distinct from her own cultural origin. The article presents Daniela’s view on the silent practice of herself and others whereby her perception takes shape through a process of constant adaptation and struggle with challenges such as anxiety, separation due to language, and ways of communicating. Amidst all these emerges the question of language choice as Daniela moves between English and Spanish for contextual reasons that unpredictably reproduce various degrees of social isolation, power disparity, and economic pressures. With insights from such anecdotal accounts, the discussion argues for the importance of comprehending silence by situating the topic in its immediate social circumstances rather than as a stand-alone construct; and eventually draws implications for second-language acquisition (SLA) in a real-world context.

The interactive effect of cultural values and government regulations on firms’ entrepreneurial orientation

PurposeConsidering that the social-cultural context is important as in which the entrepreneurs are embedded to conceptualise entrepreneurial orientation (EO), the purpose of the study is to explicate the influence of the key decision-makers’ internalised cultural values and perceptions of government regulations, to offer nuanced explanations of micro-level variations in EO of firms embedded in the same institutional context.Design/methodology/approachUsing a quantitative approach, relationships are explored in a sample of 201 Malaysian small- and medium-sized enterprises (SMEs). Partial least squares structural equation modelling (PLS-SEM) is used for the sample, and an additional test is conducted for a robustness check.FindingsThe study finds that three cultural values of the key decision-maker, namely individualism, masculinity and uncertainty avoidance, exhibit a significant association with the EO of the firms. Further, the analysis reveals that the positive effects of individualism and masculinity are enhanced when moderated by favourable perceptions of government regulations to entrepreneurship.Research limitations/implicationsThe study uses a single key informant in data collection, therefore, the possibility of single-respondent bias. The results must be interpreted in light of these limitations.Originality/valueThe study contributes to the existing literature regarding the relationship between institutions and entrepreneurship. Specifically, it articulates a microfoundations lens to explain the influence of institutions in terms of key decision-makers’ internalised cultural values (informal institutions) and their perceptions of government regulations (formal institutions) on the EO of the firm. It further elucidates the need to embrace informal and formal institutions as interdependent factors instead of treating them as standalone constructs in entrepreneurship research and policy design.

Toward a Theoretical Framework of Corporate Social Irresponsibility: Clarifying the Gray Zones Between Responsibility and Irresponsibility

In this conceptual article, we argue that defining corporate social responsibility (CSR) and corporate social irresponsibility (CSI) as opposite constructs produces a lack of clarity between responsible and irresponsible acts. Furthermore, we contend that the treatment of the CSR and CSI concepts as opposites de-emphasizes the value of CSI as a stand-alone construct. Thus, we reorient the CSI discussion to include multiple aspects that current conceptualizations have not adequately accommodated. We provide an in-depth exploration of how researchers define CSI and both identify and analyze three important gray zones between CSR and CSI: (a) the role of harm and benefit, (b) the role of the actor and intentionality, and (c) the role of rectification. We offer these gray zones as factors contributing to the present lack of conceptual clarity of the term CSI, as a concept in its own right, leading to difficulties that researchers and managers experience in categorizing CSI acts as distinct from CSR.

Comparison of Clinical and Radiographic Outcomes After Standalone Versus Cage and Plate Constructs for Anterior Cervical Discectomy and Fusion.

Anterior cervical discectomy and fusion (ACDF) has conventionally been performed using an allograft cage with a plate-and-screw construct. Recently, standalone cages have gained popularity due to theorized decreases in operative time and postoperative dysphagia. Few studies have compared these outcomes. Here, we directly compare the outcomes of plated versus standalone ACDF constructs. A single-center retrospective review of patients undergoing ACDF after June 2011 with at least 6 months of follow up was conducted. Clinical outcomes were analyzed and compared between standalone and plated constructs. Multivariate regression analysis of the primary outcome, need for revision surgery, as well as several secondary outcomes, procedure duration, estimated blood loss (EBL), length of hospital stay, disposition, and incidence of dysphagia, hoarseness, or surgical site infection, was completed. A total of 321 patients underwent ACDF and met inclusion-exclusion criteria, with mean follow-up duration of 20 months. Forty-six (14.3%) patients received standalone constructs, while 275 (85.7%) received plated constructs. Fourteen (4.4%) total revisions were necessary, 4 in the standalone group and 10 in the plated group, yielding revision rates of 8.7% and 3.6%, respectively (P = .125). Mean EBL was 98 mL in the standalone group and 63 mL in the plated group (P = .001). Mean procedure duration was 147 minutes in the standalone group and 151 minutes in the plated group (P = .800). Mean hospital stay was 3.6 days in the standalone group and 2.5 days in the plated group (P = .270). There was no significant difference in incidence of dysphagia (P = .700) or hoarseness (P = .700). Standalone ACDF demonstrates higher, but not statistically significant, revision rates than plate-and-screw constructs, without the hypothesized decreased incidence of dysphagia or hoarseness and without decreased procedure duration or EBL. Surgeons may consider limiting use of these constructs to cases of adjacent segment disease. Larger studies with longer follow up are necessary to make more definitive conclusions. 4. This study will help spine surgeons decide between using standalone or cage-and-plate constructs for ACDF.

Workplace Health Promotion, Employee Wellbeing and Loyalty during Covid-19 Pandemic—Large Scale Empirical Evidence from Hungary

Corporate social responsibility (CSR) has become an innovative strategic management tool of socially and environmentally conscious business organizations in the 21st century. Although external CSR activities are better researched, firms’ internal CSR activities such as workplace health promotion and its impact on employee wellbeing are less understood, especially during a pandemic where job security is relatively lower in many sectors of employment. Additionally, wellbeing and good health have been recognized as important targets to achieve as part of the United Nation’s Sustainable Development Goal 3. Therefore, this study investigates the relationship between health-related work benefits and employee wellbeing, satisfaction and loyalty to their workplace. Large scale survey research was performed with responses from 537 employees in Hungary and 16 hypotheses were tested. Data analysis and path modelling using PLS-SEM (Partial Least Squares Structural Equation Modelling) reveal two-layers of factors that impact employee wellbeing, satisfaction and loyalty. We term this as ‘internal locus of control’ and ‘external locus of control’ variables. Internal locus of control variables such as mental and emotional health leads to wellbeing at the workplace but do not directly impact employee satisfaction and loyalty. In contrast, external locus of control factors such as healthcare support leads to wellbeing, satisfaction and loyalty. Employer commitment to healthcare support system is found pertinent especially during the pandemic. We discover wellbeing as a unique standalone construct in this study, which is vital as is it formed by mental and emotional wellbeing of employees, albeit not a determinant of employee workplace satisfaction and loyalty. We theorize workers’ self-reliance and preservation as possible explanations to the disassociation between employee wellbeing and loyalty to workplace during times of crisis and the pandemic.

Construction of the circle in UniMath

We show that the type T Z of Z -torsors has the dependent universal property of the circle, which characterizes it up to a unique homotopy equivalence. The construction uses Voevodsky's Univalence Axiom and propositional truncation, yielding a stand-alone construction of the circle not using higher inductive types.

112. Degenerative disc disease and isthmic spondylolisthesis have similar outcomes after L5-S1 ALIF

BACKGROUND CONTEXT Anterior lumbar interbody fusion (ALIF) is a well-accepted surgical technique for lumbar spondylolisthesis and has been shown to have excellent radiographic and clinical outcomes. ALIF as a treatment for lumbar degenerative disc disease (DDD) is more controversial, with some authors reporting less reliable clinical improvement compared to other pathology. PURPOSE The purpose of this study is to compare the clinical outcomes of L5-S1 ALIF with posterior instrumentation in the setting of isthmic spondylolisthesis (IS) with L5-S1 ALIF for DDD. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE The study included 93 consecutive patients who underwent L5-S1 ALIF without direct posterior decompression for either IS (n=37) or DDD (n=56) identified. All patients who underwent ALIF for IS underwent percutaneous posterior instrumentation, while DDD patients had a stand-alone construct. OUTCOME MEASURES Baseline characteristics including age, sex, body mass index (BMI), and American Society of Anesthesiologists (ASA) physical status classification were reviewed and compared between groups. Preoperative/baseline clinical outcome measures, including visual analog scale (VAS), Short Form 12 (SF-12), Oswestry Disability index (ODI), and Veterans RAND 12 (VR-12), were collected and compared to postoperative measures at a minimum of 6 months. METHODS Changes in outcome measures from preoperative to final postoperative visit were calculated and compared between IS and DDD groups. Proportions of patients who reached minimum clinically important differences (MCID) in VAS and ODI were compared between IS and DDD groups. Bivariate and multivariate logistic regression were used to control for baseline differences in patient characteristics. RESULTS There were no significant differences between IS and DDD groups in terms of age, sex, and ASA score (p>0.05). There was a small, but statistically significant, difference in BMI between IS and DDD groups (27.32 vs 29.99, respectively, p=0.012). There were no significant differences in preoperative VAS-back, VAS-leg, and ODI between IS and DDD groups (p>0.05, Table 2). DDD patients had a lower preoperative SF-12 and VR-12 compared to IS patients (p=0.011 and p=0.01, respectively). At final follow-up, IS patients had better VAS-back, ODI, SF-12, and VR-12 scores compared to DDD patients, with no significant difference in VAS-leg scores. When comparing change from preoperative scores to final follow-up, there were no significant differences in improvement in terms of VAS, ODI, SF-12, and VR-12 between IS and DDD groups. IS and DDD groups had similar proportions of patients who achieved MCID in terms of VAS-back, VAS-leg, and ODI. CONCLUSIONS Although DDD patients have worse preoperative and postoperative clinical measures compared to IS patients, patients with DDD achieve similar levels of clinical improvement after ALIF compared to patients with IS. Additionally, DDD patients were just as likely as IS patients to achieve MCID at final follow-up after ALIF. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

3D Printed Hydrogel-Based Sensors for Quantifying UV Exposure.

Exposure to excessive ultraviolet (UV) radiation can have detrimental effects on human health. Inexpensive easy-to-use sensors for monitoring UV radiation can allow broad-scale assessment of UV exposure, but their implementation requires technology that enables rapid and affordable manufacturing of these sensors on a large scale. Herein, we report a novel three-dimensional (3D) printing procedure and printable ink composition that produce robust, flexible, and wearable UV sensors. To fabricate the sensors, a color-changing hydrogel ink was first developed from which standalone constructs were 3D printed. The ink contains alginate, gelatin, photoactive titanium dioxide nanoparticles, and dyes (methyl orange, methylene blue, and malachite green) in which the nanoparticles are used to initiate photocatalytic degradation of dyes, leading to discoloration of the dye. The sensors resemble a color-changing tattoo that loses color upon exposure to UV. The viscosity and ink composition were optimized to achieve printability and tune the mechanical properties (e.g., modulus, hardness) of the sensors. The optimized procedure enabled the one-step fabrication of mechanically stable sensors that can effectively measure outdoor sun exposure by quantifying the decrease in color, visible to the naked eye. Apart from being used as wearable sensors, these sensors have the potential to be used along with UV-based workspace sterilizing devices to ensure that surfaces have been efficiently exposed to UV. The sensors are inexpensive, stable, extremely robust, biodegradable, and easy to use. The tunability, biocompatibility, and printability of the ink offer excellent potential for developing advanced 3D printing methods that, in addition to UV sensors, can be applied more broadly to fabricate other sensing technologies for a variety of other applications.

Unravelling leadership potential: conceptual and measurement issues

ABSTRACT The status quo of the leadership potential literature is best represented as a “hot mess” of conceptual and measurement issues. In our view, the prior literature tends to conflate different constructs (i.e., predictor constructs, job-related leader behaviours, and organizational outcomes) that need to be unravelled in order to lay the foundation for future leadership potential research. To advance the field, we conduct a systematic literature review and apply a personnel selection lens to recent (35 years; 62 studies in 31 journals) leadership potential research. Our study contributes to the literature by (a) disentangling various constructs related to leadership potential and (b) proposing a guiding framework to classify and select constructs and measures for future research. Drawing on a construct and criterion validation framework widely used in personnel selection, we identify six core themes that link to construct-based theory development and disentangle various constructs in the predictor and criterion domains related to leadership potential. Specifically, our framework proposes that leadership potential is a referential concept rather than a stand-alone construct. Therefore, leadership potential research should focus on the measurement of valid predictor constructs that relate to future growth in leadership effectiveness.

The Relationship Between Flexible Perspective Taking and Emotional Well-Being: A Systematic Review of the “Self-as-Context” Component of Acceptance and Commitment Therapy

One of the core processes of acceptance and commitment therapy (ACT) is “self-as-context” (SAC). SAC is conventionally taught as an extension of mindfulness, which enables individuals to focus on a stable, grounded, and enduring sense of self that is able to have a flexible perspective. There has been a growing number of studies that have evaluated the effects of the SAC component in improving emotional well-being in various samples. The objective of this systematic review was twofold: (a) to evaluate whether SAC can be effectively taught and assessed in component analyses, and (b) to evaluate whether SAC improves emotional well-being. The electronic databases of PsycInfo and Medline were searched to identify relevant studies with the final search completed in August 2019. All studies that examined SAC as a stand-alone construct were considered. A total of 20 studies (published in 14 papers) met inclusion criteria for this review. Seven studies were based on a single-session lab trial, two studies were based on intervention trials, and 11 studies utilized cross-sectional assessment designs. On the basis of four identified studies, there is only provisional but very limited evidence to suggest that SAC can be effectively taught and implemented as a stand-alone process to manage emotional well-being. Mixed findings emerged in relation to SAC improving emotional well-being. The methodological quality of the studies was variable, which contributed to the mixed outcomes. There is limited evidence to support the use of the SAC component as a stand-alone process in ACT-based interventions, and research recommendations are discussed.

Novel Titanium Cages for Minimally Invasive Lateral Lumbar Interbody Fusion: First Assessment of Subsidence.

Introduction Implant subsidence is a potential complication of spinal interbody fusion and may negatively affect patients subjected to procedures relying on indirect decompression such as minimally invasive transpsoas lateral lumbar interbody fusion (LLIF). The porous architecture of a recently developed titanium intervertebral cage maximizes bone-to-implant contact and minimizes stress shielding in laboratory experiments; however, its subsidence rate in patients has not yet been evaluated. The goal of this current study was to evaluate implant subsidence in patients subjected to LLIF. Methods Our institutional review board-approved single-center experience included 29 patients who underwent 30 minimally invasive LLIF from July 2017 to September 2018 utilizing the novel 3D-printed porous titanium implants. Radiographs, obtained during routine postoperative follow-up visits, were reviewed for signs of implant subsidence, defined as any appreciable compromise of the vertebral endplates. Results Radiographic subsidence occurred in 2 cases (6.7%), involving 2 out of 59 porous titanium interbody cages (3.4%). Both cases of subsidence occurred in four-level stand-alone constructs. The patients remained asymptomatic and did not require surgical revision. Ten surgeries were stand-alone constructs, and 20 surgeries included supplemental posterior fixation. Conclusions In our patient cohort, subsidence of the porous titanium intervertebral cage occurred in 6.7% of all cases and in 3.4% of all lumbar levels. This subsidence rate is lower compared to previously reported subsidence rates in patients subjected to LLIF using polyetheretherketone implants.

Biomechanics of an Expandable Lumbar Interbody Fusion Cage Deployed Through Transforaminal Approach.

A novel expandable lumbar interbody fusion cage has been developed which allows for a broad endplate footprint similar to an anterior lumbar interbody fusion; however, it is deployed from a minimally invasive transforaminal unilateral approach. The perceived benefit is a stable circumferential fusion from a single approach that maintains the anterior tension band of the anterior longitudinal ligament. The purpose of this biomechanics laboratory study was to evaluate the biomechanical stability of an expandable lumbar interbody cage inserted using a transforaminal approach and deployed in situ compared to a traditional lumbar interbody cage inserted using an anterior approach (control device). Twelve cadaveric spine specimens (L1-5) were tested intact and after implantation of both the control and experimental devices in 2 (L2-3 and L3-4) segments of each specimen; the assignments of the control and experimental devices to these segments were alternated. Effect of supplemental pedicle screw-rod stabilization was also assessed. Moments were applied to the specimens in flexionextension (FE), lateral bending (LB), and axial rotation (AR). The effect of physiologic preload on construct stability was evaluated in FE. Segmental motions were measured using an optoelectronic motion measurement system. The deployable expendable transforaminal lumbar interbody fusion (TLIF) cage and control devices significantly reduced FE motion with and without compressive preload when compared to the intact condition (P < .05). Segmental motions in LB and AR were also significantly reduced with both devices (P < .05). Under no preload, the deployable expendable TLIF cage construct resulted in significantly smaller FE motion compared to the control cage construct (P < .01). Under all other testing modes (FE under 400N preload, LB, and AR), the postoperative motions of the 2 constructs did not differ statistically (P > .05). Adding bilateral pedicle screws resulted in further reduction of range of motion for all loading modes compared to intact condition, with no statistical difference between the 2 constructs (P > .05). The ability of the deployable expendable interbody cage in reducing segmental motions was equivalent to the control cage when used as a standalone construct and also when supplemented with bilateral pedicle screw-rod instrumentation. The larger footprint of the fully deployed TLIF cage combined with preservation of the anterior soft-tissue tension band may provide a better biomechanical fusion environment by combining the advantages of the traditional anterior lumbar interbody fusion and TLIF approaches.