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The complex non-centrosymmetric and chiral nature of helical structures endow materials that possess such motifs with unusual properties. However, despite their ubiquity in biological and organic systems, there is a severe lack of inorganic crystals that display helicity in extended lattices, where these unusual properties are expected to be most pronounced. Here, we report a new inorganic helical structure, gallium sulfur iodide (GaSI), within the exfoliable class of III-VI-VII (1:1:1) one-dimensional (1D) van der Waals (vdW) crystals. Through detailed structural analyses, including single-crystal X-ray diffraction, electron microscopy, and density functional theory (DFT), we elucidate the apparent noncrystallographic screw axis and the first example of an atomic scale helical structure bearing a squircular cross-section in GaSI. Crystallizing in the non-centrosymmetric P4̅ space group, we found that GaSI crystals exhibit pronounced second-harmonic generation. From diffuse reflectance spectroscopy, GaSI displays a sizeable bandgap of 3.69 eV, owing tostrong covalent interactions arising from the smaller sulfur atoms within the helix core. These results position GaSI as a promising exfoliable nonlinear optical material across a broad optical window.

Background: Anterior cruciate ligament (ACL) injuries are associated with a risk of post-traumatic osteoarthritis due to chondral damage. Magnetic resonance imaging (MRI) techniques provide excellent visualization and assessment of cartilage and can detect subtle and early chondral damage. This is often preceding clinical and radiographic post-traumatic osteoarthritis. Hypothesis: Morphologic and quantitative MRI techniques can assess early and progressive degenerative chondral changes after acute ACL injury. Study Design: Prospective longitudinal cohort. Level of Evidence: Level 3. Methods: Sixty-five participants with acute unilateral ACL injuries underwent bilateral knee MRI scans within 1 month of injury. Fifty-seven participants presented at 6 months, while 54 were evaluated at 12 months. MRI morphologic evaluation using a modified Noyes score assessed cartilage signal alteration, chondral damage, and subchondral bone status. Quantitative T1ρ and T2 mapping at standardized anatomic locations in both knees was assessed. Participant-reported outcomes at follow-up time points were recorded. Results: Baseline Noyes scores of MRI detectable cartilage damage were highest in the injured knee lateral tibial plateau (mean 2.5, standard error (SE) 0.20, P < 0.01), followed by lateral femoral condyle (mean 2.1, SE 0.18, P < 0.01), which progressed after 1 year. Longitudinal prolongation at 12 months in the injured knees was significant for T1ρ affecting the medial and lateral femoral condyles (P < 0.01) and trochlea (P < 0.01), whereas T2 values were prolonged for medial and lateral femoral condyles (P < 0.01) and trochlea (P < 0.01). The contralateral noninjured knees also demonstrated T1ρ and T2 prolongation in the medial and lateral compartment chondral subdivisions. Progressive chondral damage occurred despite improved patient-reported outcomes. Conclusion: After ACL injury, initial and sustained chondral damage predominantly affects the lateral tibiofemoral compartment, but longitudinal chondral degeneration also occurred in other compartments of the injured and contralateral knee. Clinical Relevance: Early identification of chondral degeneration post-ACL injury using morphological and quantitative MRI techniques could enable interventions to be implemented early to prevent or delay PTOA. [ABSTRACT FROM AUTHOR]

Background: It remains unclear which subset of patients with recurrent patellofemoral instability would benefit from a concomitant bony realignment procedure in addition to a medial patellofemoral ligament (MPFL) reconstruction. Purpose: To provide midterm results for patients who underwent an isolated MPFL reconstruction as part of an ongoing prospective trial. Study Design: Case series; Level of evidence, 4. Methods: Patients with recurrent patellar instability were prospectively enrolled in an institutional registry beginning in March 2014. Exclusion criteria included history of a previous surgery for patellar instability, an off-loadable (inferior/lateral) chondral defect, anterior knee pain ≥50% of their chief complaint, and a "jumping J" sign. All patients underwent primary, unilateral, isolated MPFL reconstruction regardless of their bony anatomic characteristics. Patient-reported outcome measures (PROMs), episodes of recurrent instability, and ability to return to sport were obtained annually. Radiographic measurements of baseline radiographs and MRI were obtained at baseline. Results: A total of 138 patients underwent isolated MPFL reconstruction between March 2014 and December 2019. The mean radiographic measurements were tibial tubercle–trochlear groove, 15.1 ± 4.9 mm; Caton-Deschamps index, 1.14 ± 0.16; patellar trochlear index, 46.9% ± 15.1%; trochlear depth index, 2.5 ± 1.2 mm; tibial tubercle to lateral trochlear ridge, −8.4 ± 5.7 mm; and patellar tendon to lateral trochlear ridge, 5.7 ± 6.2 mm. Trochlear dysplasia, defined as a trochlear depth index <3 mm, was present in 79/125 (63%) patients. A total of 50 patients reached ≥5 years, of whom 40 (80%) completed follow-up PROMs. A total of 119 patients reached ≥2 years, of whom 89 (75%) completed follow-up PROMs. Six patients (5%) reported recurrent instability with a mean time of 2.97 years after surgery. All PROMs improved over time except for the Pediatric Functional Activity Brief Scale (Pedi-FABS), which had no change. At 2 years, the mean changes from baseline for Knee injury and Osteoarthritis Outcome Score (KOOS) Quality of Life subscale (QOL), Pedi-FABS, International Knee Documentation Committee (IKDC) score, KOOS Physical Function Short Form (PS), and Kujala score were 42.1, 0.6, 35.1, –23.5, and 32.3, respectively. All changes had P values <.001 except for Pedi-FABS, which showed no change and had P >.999. At 5 years, the mean changes from baseline for KOOS-QOL, Pedi-FABS, IKDC, KOOS-PS, and Kujala score were 42.6, –2.8, 32.6, –21.5, and 31.6, respectively. All changes had P values <.001 except for Pedi-FABS, which showed no change and had P >.453. In total, 89% of patients returned to sport with a mean of 9.1 months. Conclusion: Midterm outcomes for patients who underwent isolated MPFL reconstruction were favorable and were maintained at 5 years. Outcomes for the expanded cohort of patients with a minimum 2-year follow-up support previously published results. [ABSTRACT FROM AUTHOR]

Background: Anterior cervical discectomy and fusion (ACDF) is known to elicit adverse biomechanical effects on immediately adjacent segments; however, its impact on the kinematics of the remaining nonadjacent cervical levels has not been understood. This study aimed to explore the biomechanical impact of ACDF on kinematics beyond the immediate fusion site. We hypothesized that compensatory motion following single-level ACDF is not predictably distributed to adjacent segments due to compensation from noncontiguous levels. Methods: Six fresh-frozen cervical spines (C2-T1) underwent fluoroscopic screening and sagittal and coronal reformats from computed tomography scans and were utilized to grade segmental degeneration. Each specimen was tested to 30° of flexion and extension intact and following single-level ACDF at the C5-C6 level. The motions of each vertebral body were tracked using 3-dimensional (3D) motion capture into an inverse kinematics model, facilitating correlations between the 3D reconstruction from computed tomography images and the 3D motion capture data. This model was used to calculate each level's flexion/extension range of motion (ROM). Results: Single-level fusion at the C5-C6 level across all specimens resulted in a significant motion reduction of -6.8° (P = 0.002). No significant change in ROM occurred in the immediate adjacent segments C4-C5 (P = 0.07) or C6-C7 (P = 0.15). Hypermobility was observed in 2 specimens (33%) exclusively in adjacent segments. In contrast, the other 4 spines (66%) displayed hypermobility at noncontiguous segments. Hypermobility occurred in 42% (5/12) of the adjacent segments, 28% (5/18) of the noncontiguous segments, and 50% (3/6) of the cervicothoracic segments. Conclusion: Single-level ACDF impacts ROM beyond adjacent segments, extending to noncontiguous levels. Compensatory motion, not limited to adjacent levels, may be influenced by degenerative changes in noncontiguous segments. Surprisingly, hypermobility may not occur in adjacent segments after ACDF. Clinical Relevance: Overall, the multifaceted biomechanical effects of ACDF underscore the need for a comprehensive understanding of cervical spine dynamics beyond immediate adjacency, and it needs to be taken into consideration when planning single-level ACDF. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

Background: Heart Failure (HF) is associated with increased morbidity and mortality. Identification of patients at risk for adverse events could lead to improved outcomes. Few studies address the association of echocardiographic-derived PAWP with exercise capacity, readmissions, and mortality in HF. Methods: HF-ACTION enrolled 2331 outpatients with HF with reduced ejection fraction (HFrEF) who were randomized to aerobic exercise training versus usual care. All patients underwent baseline echocardiography. Echocardiographic-derived PAWP (ePAWP) was assessed using the Nagueh formula. We evaluated the relationship between ePAWP to clinical outcomes. Results: Among the 2331 patients in the HF-ACTION trial, 2125 patients consented and completed follow-up with available data. 807 of these patients had complete echocardiographic data that allowed the calculation of ePAWP. Of this cohort, mean age (SD) was 58 years (12.7), and 255 (31.6%) were female. The median ePAWP was 14.06 mmHg. ePAWP was significantly associated with cardiovascular death or HF hospitalization (Hazard ratio [HR] 1.02, coefficient 0.016, CI 1.002–1.030, p = 0.022) and all-cause death or HF hospitalization (HR 1.01, coefficient 0.010, CI 1.001–1.020, p = 0.04). Increased ePAWP was also associated with decreased exercise capacity leading to lower peak VO2 (p = < 0.001), high Ve/VCO2 slope (p = < 0.001), lower exercise duration (p = < 0.001), oxygen uptake efficiency (p = < 0.001), and shorter 6-MWT distance (p = < 0.001). Conclusions: Among HFrEF patients, echocardiographic-derived PAWP was associated with increased mortality, reduced functional capacity and heart failure hospitalization. ePAWP may be a viable noninvasive marker to risk stratify HFrEF patients. [ABSTRACT FROM AUTHOR]

Background: The prevalence of ambulatory total hip arthroplasty (THA) is rising, but it is not appropriate for all patients. Preoperative patient selection considers medical and social factors but overlooks patients' prior level of physical function. Purpose: The aim of this study was to evaluate if preoperative physical function, measured by the Timed-Up-and-Go (TUG) test, is associated with length of stay (LOS) in patients who underwent primary THA. Methods: A retrospective study was performed using 396 patients who underwent primary THA within a 2-month period at a single institution. Regression analysis evaluated the relationship between preoperative TUG scores and hospital LOS. Receiver-operating characteristic (ROC) curves were generated to identify a cutoff TUG score associated with LOS longer than 24 hours. Results: Univariate regression analysis of those discharged in less than 24 hours and those discharged in more than 24 hours found lower TUG scores (10.7 vs 13.7, respectively) were associated with patient discharge within 24 hours. Multivariate regression analysis showed a higher TUG score (adjusted odds ratio [aOR]: 0.91, 95% confidence interval [CI]: 0.84-0.99) was associated with decreased odds of discharge within 24 hours. Receiver-operating characteristic curve analysis was performed on the entire study cohort and the ambulatory surgery group and identified TUG scores of 10.3 and 10.5 seconds, respectively, associated with LOS of less than 24 hours (OR full cohort: 3.02, 95% CI: 1.94-4.71; OR ambulatory surgery: 2.97, 95% CI: 1.90-4.60). Sensitivity and specificity were not sufficient to support the use of these cutoff scores alone in predicting LOS. Conclusion: Although we were unable to establish a cutoff TUG score in patients who underwent primary THA that could determine LOS of more than 24 hours, the preoperative TUG score may be useful as a tool to aid in identifying patients who may require a longer hospital LOS. Further study is needed. [ABSTRACT FROM AUTHOR]

Background: Research has identified predictive factors for inpatient complications and short-term recovery following total knee arthroplasty (TKA) and total hip arthroplasty (THA). Predictors that may influence length of care in outpatient physical therapy (PT) have yet to be examined. Doing so may improve the quality and efficiency of PT care following TKA and THA. Purpose: The aim of this study was to determine factors associated with a higher utilization of outpatient PT visits for patients who have had primary THA or TKA. Methods: A retrospective cohort study was performed using a population of 5147 patients who underwent THA and TKA between January 2017 and October 2022. Demographic and clinical factors were analyzed to determine which factors influenced PT utilization. Results: Our multivariable linear regression model revealed that female sex, need for inpatient PT visits, and TKA as opposed to THA were significantly associated with an increase in outpatient PT visits. Older age, number of telerehabilitation visits, and history of depression were associated with fewer outpatient PT visits while accounting for all other variables. Conclusions: The results of this retrospective analysis may help to identify some potential factors including TKA vs THA, patient age, and a history of depression that can be evaluated prospectively in future studies to determine whether they predict subsequent outpatient PT utilization. [ABSTRACT FROM AUTHOR]

Background: Post-acute care for orthopedic surgery patients continues to evolve with the reduction in hospital length of stay (LOS), shift to ambulatory surgery, increased number of surgeries, and focus on value-based care. Purpose: We sought to examine outcomes of a cohort of lower-extremity arthroplasty patients receiving telephysical therapy (TelePT) according to hospital LOS, as a means of exploring the viability of TelePT as a value-based discharge option. Methods: A retrospective review was conducted of patients who participated in our institution's HSS@Home TelePT program after undergoing primary unilateral hip or knee arthroplasty, unicondylar knee replacement, or hip resurfacing. Demographic data and outcomes such as hospital LOS, number of days between discharge and TelePT evaluation, number of TelePT visits, number of re-admissions, Hip dysfunction and Osteoarthritis Outcome (HOOS Jr.) or Knee injury and Osteoarthritis Outcome (KOOS Jr.) scores, and patient satisfaction scores were collected. Patients were divided into categories based on hospital LOS to help determine the versatility of program. Results: In the 2814 patients included, we observed an average of 4.1 TelePT visits; 1% of patients were readmitted within 90 days, and 97% of patients were satisfied or highly satisfied. There was no difference in HOOS or KOOS Jr. scores at each follow-up time point, except for the 6-month HOOS Jr. scores. Conclusion: This retrospective study suggests that TelePT may be a viable option for care of lower-extremity arthroplasty patients in the post-acute setting, regardless of hospital LOS. As a discharge option, it may meet the needs of select patients to fill a gap in providing value-based care. [ABSTRACT FROM AUTHOR]

Background: The Risk Assessment and Prediction Tool (RAPT) and the Activity Measure for Post-Acute Care "6-Clicks" Mobility Score (AM-PAC) are validated discharge planning tools for patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). Planning for discharge with these tools considers very different factors and it is important to determine if they relate. Purpose: We sought to determine whether the preoperative RAPT score would correlate with postoperative AM-PAC score for predicting discharge destination for THA and TKA populations. Secondarily, we sought to examine whether the AM-PAC and RAPT scores would remain statistically significant predictors of discharge destination despite covariates. Methods: A retrospective cohort study was performed for patients who underwent THA or TKA from January 2020 to December 2022 at a specialty orthopedic hospital. Primary variables included the RAPT score, the AM-PAC score, and discharge disposition. Correlation between AM-PAC and RAPT scores was tested using Pearson's correlation coefficient, and association between both scores and discharge destination was tested using chi-square tests and multivariable logistic regression. Results: Our comparison of AM-PAC scores and RAPT scores found a statistically significant, positive correlation in both THA and TKA patients. Regression analysis found that increased RAPT and AM-PAC scores resulted in higher odds of being discharged home for both populations, after adjusting for all other variables. In both cohorts, patients discharged to a facility were more likely to be female, be over the age of 70 years, have Medicare/Medicaid insurance, and have a higher number of preoperative social work visits or any incidence of an intraoperative or hospital complication. Conclusions: This retrospective study found that RAPT score correlated with AM-PAC score for predicting discharge destination for elective THA and TKA populations, suggesting that these scores may be predictors of home discharge destination even when accounting for covariates. Further study is recommended. [ABSTRACT FROM AUTHOR]

Background: Increasing numbers of patients are undergoing total joint arthroplasty as a treatment for osteoarthritis, which can be an anxiety-provoking experience. Setting expectations through a preoperative physical therapy (pre-op PT) session can alleviate some of these stressors, potentially decrease hospital length of stay (LOS), and promote home discharge. Purpose: We sought to determine whether attending a pre-op PT session is associated with decreased hospital LOS and home discharge in total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients. Methods: A retrospective cohort study was performed of 20,822 patients who underwent THA or TKA between January 2020 and December 2023. Pre-op PT attendance and covariates, including patient demographics and clinical data, were collected and analyzed for association with LOS and discharge disposition. Results: Unadjusted univariate analysis revealed that THA and TKA patients who received pre-op PT had a significantly lower average LOS and were more likely to be discharged home. Our multivariate regression model showed that pre-op PT was not significantly associated with LOS in both groups but was significantly associated with home discharge among THA patients. Conclusions: Our retrospective study of the effect of pre-op PT education on LOS and discharge disposition for elective THA and TKA patients found different results in univariate and multivariate analysis. Further study is needed to confirm the association found on multivariate analysis between pre-op PT and home discharge in THA patients. [ABSTRACT FROM AUTHOR]

Introduction: Spinal cord infarction is a rare but serious neurologic complication of spinal anesthesia. Direct vessel injury, intra-arterial anesthetic injection, and anesthetic-induced local hypotension are potential mechanisms of infarction during this procedure. The proximity of the artery of Adamkiewicz to the spinal levels used for spinal anesthesia may also play a role. This case of unilateral anterior spinal artery syndrome highlights the potential for an atypical pattern of injury and deficits due to the complexity of the spinal cord's anterior circulation. Case Presentation: We present a 38-year-old female patient who presented with left lower extremity weakness, loss of temperature sensation, and urinary retention following spinal anesthesia for cesarian section. Magnetic resonance imaging of the spine demonstrated T2 hyperintensities in the left central spinal cord from T8 to the conus medullaris. A diagnosis of spinal cord infarction was made after lumbar puncture testing showed no evidence of inflammatory myelitis. The patient was treated with steroids empirically until lumbar puncture testing showed no inflammation. The patient was discharged on daily aspirin with persistent left lower extremity weakness and loss of temperature sensation. A plan for outpatient physical therapy was made for rehabilitation. Conclusion: Awareness of the potential for spinal cord infarction secondary to spinal anesthesia must increase among anesthesiologists, obstetricians, and neurologists. The risk of systemic hypotension during and after spinal anesthesia is important to recognize for both primary and secondary prevention of this complication. The hyperacute onset of myelopathic symptoms should point neurologists to investigate an ischemic etiology in the proper clinical context. [ABSTRACT FROM AUTHOR]

Introduction: Academic cardiac surgeons are productive researchers and innovators. We sought to perform a comprehensive machine learning (ML)-based characterization of cardiac surgery research over the past 40 y to identify trends in research pursuits., Methods: US-based academic websites were queried for surgeon profiles. Publications since 1980 were obtained from Web of Science, and publication classifications (e.g., "human", "animal") were collected through the National Institutes of Health iCite tool. Publications were deemed "basic or translational" if >50% of their classification was under "animal" or "molecular or cell", and "clinical" if otherwise. ML-based clustering was performed on publication titles and Medical Subject Heading terms to identify research topics., Results: A total of 944 cardiac surgeons accounted for 48,031 unique publications. Average citations per year have decreased since 1980 (P < 0.001). The percentage of basic or translational publications by cardiac surgeons has decreased over time (P < 0.001), comprising of only 8% of publications in 2022. Adult cardiac surgeons, those who received an F32, K08, or R01, and those with a PhD were more likely to publish basic or translational research. Top areas of basic or translational research were myocardial reperfusion, aortic aneurysms or remodeling, and transplant immunology. Major areas of clinical research included aortic disease, aortic valve disease, and mechanical circulatory support. Collaboration analysis revealed that 55% of publications were single-center, and the yearly percentage of these publications has decreased over time (P < 0.001)., Conclusions: Cardiac surgeons are performing less basic or translational research relative to clinical research than ever before. The majority of publications over the past 40 y did not involve cross-center collaboration. Continued support for clinical research is needed, while also encouraging collaborative basic or translational science to foster innovation in patient care., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The factors affecting the formation and crystal structures of unusual 6d 1 Th(III) square planar aryloxide complexes, as exemplified by [Th(OAr Me ) 4 ] 1- (OAr Me = OC 6 H 2 t Bu 2 -2,6-Me-4), were explored by synthetic and reduction studies of a series of related Th(IV) tetrakis(aryloxide) complexes, Th(OAr R ) 4 (OAr R = OC 6 H 2 t Bu 2 -2,6-R-4). Specifically, electronic, steric, and countercation effects were explored by varying the aryloxide ligand, the alkali metal reducing agent, and the alkali metal chelating agent. Salt metathesis reactions between ThBr 4 (DME) 2 (DME = 1,2-dimethoxyethane) and 4 equiv of the appropriate potassium aryloxide salt were used to prepare a series of Th(IV) aryloxide complexes in high yields: Th(OAr H ) 4 (OAr H = OC 6 H 3 t Bu 2 -2,6), Th(OAr tBu ) 4 (OAr tBu = OC 6 H 2 t Bu 3 -2,4,6), Th(OAr OMe ) 4 (OAr OMe = OC 6 H 2 t Bu 2 -2,6-OMe-4), and Th(OAr Ph ) 4 (OAr Ph = OC 6 H 2 t Bu 2 -2,6-Ph-4). Th(OAr H ) 4 can be reduced by KC 8 , Na, or Li in the absence or presence of 2.2.2-cryptand (crypt) or 18-crown-6 (crown) to form dark purple solutions that have EPR and UV-visible spectra similar to those of the square planar Th(III) complex, [Th(OAr Me ) 4 ] 1- . Hence, the para position of the aryloxide ligand does not have to be alkylated to obtain the Th(III) complexes. Furthermore, reduction of Th(OAr OMe ) 4 , Th(OAr tBu ) 4 , and Th(OAr Ph ) 4 with KC 8 in THF generated purple solutions with EPR and UV-visible spectra that are similar to those of the previously reported Th(III) anion, [Th(OAr Me ) 4 ] 1- . Although many of these reduction reactions did not produce single crystals suitable for study by X-ray diffraction, reduction of Th(OAr H ) 4 , Th(OAr tBu ) 4 , and Th(OAr OMe ) 4 with Li provided X-ray quality crystals whose structures had square planar coordination geometries. Reduction of Th(OAr Ph ) 4 with Li also gave a product with EPR and UV-visible spectra that matched those of [Th(OAr Me ) 4 ] 1- , but X-ray quality crystals of the reduction product were too unstable to provide data. Neither Th(Odipp) 4 (THF) 2 (Odipp = OC 6 H 3 i Pr 2 -2,6) nor Th(Odmp) 4 (THF) 2 (Odmp = OC 6 H 3 Me 2 -2,6) could be reduced to Th(III) products under similar conditions. Reduction of U(OAr H ) 3 (THF) with KC 8 in the presence of 2.2.2-cryptand (crypt) was examined for comparison and formed [K(crypt)][U(OAr H ) 4 ], which has a tetrahedral arrangement of the aryloxide ligands. Moreover, no further reduction was observed when either [K(crypt)][U(OAr H ) 4 ] or [K(crown)(THF) 2 ][U(OAr H ) 4 ] were treated with KC 8 or Li.