The Impact of Positive Versus Negative Exemplar‐Based Instructions on a Creative Writing Task

ABSTRACT Some types of instructions for creativity tasks (such as explicitly telling people to be creative) can boost performance. Showing people examples or telling them ways of approaching the problem before they begin a creativity task can help, but results are mixed about whether it is better to emphasize positive examples/approaches that can be emulated or negative examples/approaches that should be avoided. In this study, 198 participants wrote two brief essays—one under a positive exemplar instructional condition and one under a negative exemplar instructional condition. The results showed that the stories of participants written under the positive instructional condition were rated significantly higher in overall creativity, originality, and humor than the stories written under the negative instructional condition. Results are discussed in light of previous findings.

How and When Does Coworker Knowledge Sharing Influence Employee Creativity? A Moderated Mediation Model

ABSTRACT This study investigates the mechanisms and conditions through which coworker knowledge sharing influences employee creativity, grounded in the conservation of resources (COR) theory. Specifically, the study proposes that employee self‐efficacy functions as a mediating mechanism in the relationship between coworker knowledge sharing and employee creativity, while job demands serve as a boundary condition for this indirect effect. To test these hypotheses, two studies were conducted in South Korea. Study 1 analyzed data from 198 supervisor–employee dyads within a state‐owned enterprise, while Study 2 examined data from 241 dyads across six of the nation's largest private companies. Results indicate that coworker knowledge sharing significantly enhances employee creativity, with self‐efficacy fully mediating this relationship. Furthermore, the findings reveal that job demands moderate both the effect of coworker knowledge sharing on employee self‐efficacy and the indirect effect of coworker knowledge sharing on employee creativity via self‐efficacy. The study discusses implications for both theory and practice.

Degradation of lubricating molecules in synovial fluid alters chondrocyte sensitivity to shear strain

Abstract Articular joints facilitate motion and transfer loads to underlying bone through a combination of cartilage tissue and synovial fluid, which together generate a low‐friction contact surface. Traumatic injury delivered to cartilage and the surrounding joint capsule causes secretion of proinflammatory cytokines by chondrocytes and the synovium, triggering cartilage matrix breakdown and impairing the ability of synovial fluid to lubricate the joint. Once these inflammatory processes become chronic, posttraumatic osteoarthritis (PTOA) development begins. However, the exact mechanism by which negative alterations to synovial fluid leads to PTOA pathogenesis is not fully understood. We hypothesize that removing the lubricating macromolecules from synovial fluid alters the relationship between mechanical loads and subsequent chondrocyte behavior in injured cartilage. To test this hypothesis, we utilized an ex vivo model of PTOA that involves subjecting cartilage explants to a single rapid impact followed by continuous articulation within a lubricating bath of either healthy synovial fluid, phosphate‐buffered saline (PBS), synovial fluid treated with hyaluronidase, or synovial fluid treated with trypsin. These treatments degrade the main macromolecules attributed with providing synovial fluid with its lubricating properties; hyaluronic acid and lubricin. Explants were then bisected and fluorescently stained to assess global and depth‐dependent cell death, caspase activity, and mitochondrial depolarization. Explants were tested via confocal elastography to determine the local shear strain profile generated in each lubricant. These results show that degrading hyaluronic acid or lubricin in synovial fluid significantly increases middle zone chondrocyte damage and shear strain loading magnitudes, while also altering chondrocyte sensitivity to loading.

Bone and Nerve Response to Sciatic Compression Neuropathy in a Rabbit Model

ABSTRACT Compression neuropathy is a prevalent medical condition, including common types such as carpal tunnel syndrome, cubital tunnel syndrome, sciatica, and many others. While the neurological consequences are well understood, the effects on bone properties and the potential downstream impact on fracture risk remain less clear. This study aimed to assess the influence of compressive neuropathy on bone properties using a rabbit model of sciatic nerve compression. We hypothesized that compressive neuropathy could adversely alter bone properties. Five New Zealand white rabbits underwent surgery to induce perineural scarring in the sciatic nerve, with the contralateral limb serving as a sham control. Bone mineral density (BMD), mechanical strength, and bone signaling proteins were evaluated through microcomputed tomography (μCT), four‐point bending tests, and ELISA assays, respectively. Sciatic nerve histology was analyzed using VEGF and Nissl staining to assess axon and Schwann cell densities and quantified using image analysis software. The results showed no significant differences in BMD, biomechanical properties, or key bone signaling proteins (OPG and RANKL) between the affected and control tibias. These findings suggest that compression neuropathy does not significantly impact bone properties in the rabbit model.

Patellofemoral Cartilage Changes Are Not Associated With Quadriceps Metrics After ACLR With Patellar Tendon Autografts

ABSTRACT Quadriceps dysfunction (e.g., weakness or atrophy) is often implicated in the increased prevalence of posttraumatic osteoarthritis (PTOA) following anterior cruciate ligament reconstruction (ACLR). However, the relationship between quadriceps dysfunction and PTOA development relies on limited insight. To this end, magnetic resonance T1rho relaxation times directly assess cartilage composition, yet the long‐term relationship between cartilage composition and quadriceps dysfunction has not yet been explored within a single graft type. Our objectives were to assess cartilage composition using T1rho values 3 years post‐ACLR via patellar tendon autograft and to examine associations between quadriceps strength or volume and cartilage composition. Twenty‐four individuals with ACLR (male/female = 15/9, age = 22.8 ± 3.6 years, BMI = 23.2 ± 1.9, time since surgery = 3.3 ± 0.9 years) and 24 Controls (male/female = 14/10, age = 22.0 ± 3.1 years, BMI = 23.3 ± 2.6) participated. Linear mixed‐effects models assessed T1rho values between ACLR, Contralateral, and Control Limbs. Linear regressions determined associations between quadriceps strength or volume with T1rho in significant regions identified by the linear mixed‐effects models. T1rho values in the ACLR limb were 7%–12% longer in the medial and lateral patella, and trochlea compared to Contralateral and/or Control limbs ( p  = 0.009–0.049), with no associations with strength or volume ( p  > 0.05). Three years following ACLR via patellar tendon autograft, the patellofemoral joint exhibited compositional changes that were not associated with quadriceps strength or size. Future studies should explore if similar changes occur with other graft types and investigate the role of additional factors known to impact joint health (e.g., walking mechanics).

Risk of Distal Femur Fracture in Antegrade Intramedullary Nail Fixation of Proximal Femur Fractures: A Finite Element Study

ABSTRACT Surgeons often use long antegrade intramedullary nails (aIMNs) when fixing fractures of the proximal femur in geriatric patients. However, risk of peri‐implant fracture in relation to aIMN termination level has not yet been studied. We therefore studied the correlation between aIMN nail tip termination level and extent of distal femur fracture in three different loading scenarios using finite element models of seven different length aIMNs. These were loaded into 3D models of synthetic osteoporotic femurs, which were loaded in single‐leg stance (SLS) with body weight load at the femoral head, torsion (TOR) counterclockwise to failure with 120 Nm of torque, and distal impact/fall (DIF) simulating direct fall on the knees at 1000 mm/sec. The maximum stress in SLS and percentage of failed elements for TOR and DIF were recorded. For SLS, aIMN tip termination and maximum stress were not correlated ( ρ  = 0.1429, p  = 0.7599) and there was no apparent trend in the data. For TOR, more proximal aIMN tip termination demonstrated a significant correlation with greater percentage of failed area ( ρ  = 0.9286, p  = 0.0025). For DIF, aIMN tip termination was not correlated with the percentage of failed elements ( ρ  = −0.6071, p  = 0.1482), but demonstrated a statistically significant Gaussian relationship (coeffs:a<math display="inline" altimg="urn:x-wiley:07360266:media:jor26113:jor26113-math-0001" xmlns="http://www.w3.org/1998/Math/MathML" wiley:location="equation/jor26113-math-0001.png"><mrow><mrow><mi>a</mi></mrow></mrow></math>  = 2.22 ( p  = 1.13 × 10 −3 ),b<math display="inline" altimg="urn:x-wiley:07360266:media:jor26113:jor26113-math-0002" xmlns="http://www.w3.org/1998/Math/MathML" wiley:location="equation/jor26113-math-0002.png"><mrow><mrow><mi>b</mi></mrow></mrow></math>  = 58.61 ( p  = 1.89 × 10 −5 ),c<math display="inline" altimg="urn:x-wiley:07360266:media:jor26113:jor26113-math-0003" xmlns="http://www.w3.org/1998/Math/MathML" wiley:location="equation/jor26113-math-0003.png"><mrow><mrow><mi>c</mi></mrow></mrow></math>  = 17.46 ( p  = 1.79 × 10 −3 )) where 60 mm aIMN tip termination demonstrated the greatest percentage of failed area. Therefore, we found a strong linear relationship between more proximal aIMN termination in the femur and extent of failure in TOR. There was a statistically significant Gaussian relationship between metaphyseal termination and extent of failure in DIF.

Longitudinal Progression of Traumatic Bone Marrow Lesions Following Anterior Cruciate Ligament Injury: Associations With Knee Pain and Concomitant Injuries

ABSTRACT Traumatic bone marrow lesions (BMLs) occur in ~80% of anterior cruciate ligament (ACL) injuries, typically in the lateral femoral condyle (LFC) and lateral tibial plateau (LTP). Associated with microfractures, vascular proliferation, inflammation, and bone density changes, BMLs may contribute to posttraumatic osteoarthritis. However, their relationship with knee pain is unclear. This study examined the prevalence, characteristics, and progression of BMLs after ACL injury, focusing on associations with pain, meniscal and ligament injuries, and fractures. Participants ( N  = 100, aged 14–55) with MRI‐confirmed ACL tears were scanned within 6 weeks post‐injury (mean = 30.0, SD = 9.6 days). BML volumes were quantified using a validated machine learning method, and pain assessed via the Knee Injury and Osteoarthritis Outcome Score (KOOS). Analyses included t ‐tests, Mann–Whitney U, chi‐square, and Spearman correlations with false discovery rate correction. BMLs were present in 95% of participants, primarily in the LFC and LTP. Males had 33% greater volumes than females ( p  < 0.05), even after adjusting for BMI. Volumes were higher in cases with depression fractures ( p  = 0.022) and negatively associated with baseline KOOS Symptoms. At 1 year, 92.68% of lesions (based on lesion counts) resolved in Nonsurgical participants, with a 96.13% volume reduction ( p  < 0.001). KOOS outcomes were similar between groups, except for slightly better Pain scores in the Nonsurgical group. Baseline Pain and Sport scores predicted follow‐up outcomes. BMLs are common post‐ACL injury, vary by sex and fracture status, and modestly relate to early symptoms. Most resolve within a year, with limited long‐term differences by surgical status.

Identification of Antibodies to Chondrocyte and Synoviocyte Antigens in Equine Osteoarthritis

ABSTRACT Innate immune responses within the joint are now known to play a key role in osteoarthritis (OA) pathogenesis. However, comparatively little is known regarding the role of adaptive immune responses in OA, and whether they may be important for initiating and sustaining progressive low‐level joint inflammation. Therefore, we evaluated spontaneous osteoarthritis in horses to investigate whether antibodies recognizing live joint cells (chondrocytes, synoviocytes) were present in blood or synovial fluid, and to identify possible cellular target antigens. We found that horses with advanced OA had antibodies present in synovial fluid (SF) and plasma that recognized antigens expressed by chondrocytes and synoviocytes isolated from healthy joint tissues. Antibody concentrations correlated with clinical and arthroscopic scoring of OA severity. Antigenic targets for antibody recognition were expressed intracellularly and proteomic analysis of a prominent 60 kD protein band identified several proteins, including vimentin, calreticulin, and Hsp60, all of which are known to be antibody targets in patients with rheumatoid arthritis. Histological analysis of synovial biopsy samples from OA horses revealed the presence of numerous tertiary lymphoid structures with well‐formed germinal centers, consistent with local antibody production within the joint synovium. Taken together, these studies in equine osteoarthritis revealed the presence of antibodies recognizing antigens expressed by live cells in the joint, which resembled similar immunologic processes recently described in rheumatoid arthritis. Broader questions raised by these findings include identification of triggers for local antibody production and new strategies to target this immune pathway in progressive OA.

Measured energy expenditure according to the phases of critical illness: A descriptive cohort study

Abstract Background Indirect calorimetry is recommended for directing energy provision in the intensive care unit (ICU). However, limited reports exist of measured energy expenditure according to the phases of critical illness in large cohorts of patients during ICU admission. This study aimed to analyze measured energy expenditure overall in adult patients who were critically ill and across the different phases of critical illness. Methods Indirect calorimetry measurements completed at a mixed ICU between January 2010 and July 2019 were eligible. Measured energy expenditure was analyzed and reported as kcal/day and kcal/kg/day overall, as the percentage increase above predicted basal metabolic rate and according to the phases of critical illness; acute early (day 1–2), acute late (day 3–7) and recovery (>7 days) phases using mixed effects linear modelling. Results There were 629 patients with 863 measurements included; age mean (standard deviation) 48 (18) years, 68% male and 269 (43%) with a traumatic brain injury. Measured energy expenditure overall was 2263 (626) kcal/day (30 (7) kcal/kg/day), which corresponded to a median [interquartile range] of 135 [117–155] % increase above predicted basal metabolic rate. In patients with repeat measurements ( n  = 158), measured energy expenditure (mean ± standard error) increased over time; 27 ± 0.5 kcal/kg/day in the early acute, 30 ± 0.4 kcal/kg/day in the late acute, and 31 ± 0.4 kcal/kg/day in the recovery phases of critical illness ( P  < 0.001). Conclusion In a large cohort of ICU patients, measured energy expenditure was 135% above the basal metabolic rate and increased from the early acute to the late acute and recovery phases of critical illness.

Ustekinumab is safe and effective in pediatric patients with Crohn's disease