Clinical Results and CT Analysis of ISA Stemless at a Minimum Follow-up of 2 Years.

INTRODUCTION: The utilization of stemless anatomic total shoulder arthroplasty is on the rise. Epiphyseal fixation leads to radiological bone remodeling, which has been reported to exceed 40% in certain studies series. The aim of this study was to present the clinical and radiological outcomes of a stemless implant with asymmetric central epiphyseal fixation at an average follow-up of 31 months. MATERIALS: This retrospective multicenter study examined prospective data of patients undergoing total anatomic arthroplasty with ISA Stemless implant and followed up at least 2 years. Clinical assessment included preoperative and final follow-up measurements of active range of motion (ROM), Constant score, and Subjective Shoulder Value (SSV). Anatomical epiphyseal reconstruction and bone remodeling at the 2-year follow-up were assessed by standardized Computed Tomography Scanner (CT scan). Statistical analysis employed unpaired Student's t-test or chi-squared test depending on the variable type, conducted using EasyMedStat software (version 3.22; www.easymedstat.com). RESULTS: Fifty patients (mean age 68 years, 62% females) were enrolled, with an average follow-up of 31 months (24-44). Primary osteoarthritis (68%) with type A glenoid (78%) was the prevailing indication. The mean Constant score and SSV improved significantly from 38 ± 11 to 76 ± 11 (p<0.001) and from 31% ± 16 to 88% ± 15 (p<0.001) respectively at the last follow-up. Forward elevation, external rotation and internal rotation ROM increased by 39° ± 42, 28° ± 21 and 3,2 ± 2,5 points respectively, surpassing the Minimally Clinically Important Difference (MCID) after total shoulder arthroplasty. No revisions were necessary. CT scans identified 30% osteolysis in the posterior-medial calcar region, devoid of clinical repercussions. No risk factors were associated with bone osteolysis. CONCLUSION: At an average follow-up of 31 months, ISA Stemless implant provided favorable clinical results. CT analysis revealed osteolysis-like remodeling in the posterior-medial zone of the calcar (30%), without decline in clinical outcomes and revisions. Long-term follow-up studies are mandated to evaluate whether osteolysis is associated with negative consequences.

Male sex, revision surgery, low volume of anterior cruciate ligament remnant, and significant instability are risk factors for Posterior Root Tear of the Lateral Meniscus in patients undergoing Anterior Cruciate Ligament Reconstruction.

PURPOSE: This multicenter study aimed to determine the incidence of lateral meniscus posterior root tears (LMPRTs) in patients undergoing ACL reconstruction and identify associated risk factors. METHODS: We conducted a retrospective, multicenter study using data from the Francophone Arthroscopic Society's registry. The study included all the patients in the registry who underwent ACL reconstruction surgery between June 2020 and June 2023, we excluded incomplete data. We compared delay from injury to surgery between LMPRTs group and No LMPRTs group. Variables investigated as potential risk factors for LMPRTs included age, sex, nature of surgery (primary or revision), pivot shift test result, side-to-side laxity under anesthesia, presence of ACL remnant, occurrence of medial meniscal tear, and presence of collateral ligament injury. Risk factors were analyzed using a logistic regression model. RESULTS: Among the 5359 patients analyzed, LMPRTs occurred in 7.0% (n=375) of cases during ACL reconstruction. Mean age at surgery was 29.3 +/- 10.3 years old [11-77]. Concerning delay to surgery, the mean time was 8.4 +/- 23.1 weeks [0.0-347.2] in the No LMPRTs group and 6.5 +/- 10.2 weeks [0.2-61.6] in the LMPRTs group (p = 0.109). Univariate analysis revealed that male sex (p < 0.001), revision surgery (p < 0.001), medial meniscal injury (p = 0.007), ACL remnant (0% vs > 70%, <10% vs > 70%, 10 to 30% vs > 70%, 30 to 50% vs > 70%, 50 to 70% vs > 70%; p < 0.001) and higher pivot shift grade (p = 0.011) were significantly associated with a presence of LMPRTs. Age, side-to-side laxity, and collateral ligament injury were not found to be significant risk factor In multivariate analysis : male sex, revision surgery, pivot shift test result and a low volume of ACL remnant remained significant. Side to side laxity was also a significant factor in multivariate analysis. CONCLUSION: This study identified male sex, revision surgery, low volume of ACL remnant, side to side laxity and higher grade of pivot shift as significant risk factors for LMPRTs during ACL reconstruction.

Unconventional Band Structure via Combined Molecular Orbital and Lattice Symmetries in a Surface-Confined Metallated Graphdiyne Sheet.

Graphyne (GY) and graphdiyne (GDY)-based monolayers represent the next generation 2D carbon-rich materials with tunable structures and properties surpassing those of graphene. However, the detection of band formation in atomically thin GY/GDY analogues has been challenging, as both long-range order and atomic precision have to be fulfilled in the system. The present work reports direct evidence of band formation in on-surface synthesized metallated Ag-GDY sheets with mesoscopic (≈1 µm) regularity. Employing scanning tunneling and angle-resolved photoemission spectroscopies, energy-dependent transitions of real-space electronic states above the Fermi level and formation of the valence band are respectively observed. Furthermore, density functional theory (DFT) calculations corroborate the observations and reveal that doubly degenerate frontier molecular orbitals on a honeycomb lattice give rise to flat, Dirac and Kagome bands close to the Fermi level. DFT modeling also indicates an intrinsic band gap for the pristine sheet material, which is retained for a bilayer with h-BN, whereas adsorption-induced in-gap electronic states evolve at the synthesis platform with Ag-GDY decorating the (111) facet of silver. These results illustrate the tremendous potential for engineering novel band structures via molecular orbital and lattice symmetries in atomically precise 2D carbon materials.

Metabolic activity of Planktothrix rubescens and its consequences on oxygen dynamics in laboratory experiment: A stable isotope study.

Fluctuations in dissolved oxygen (DO) contents in natural waters can become intense during cyanobacteria blooms. In a reconnaissance study, we investigated DO concentrations and stable isotope dynamics during a laboratory experiment with the cyanobacterium Planktothrix rubescens in order to obtain insights into primary production under specific conditions. This observation was extended to sub-daily timescales with alternating light and dark phases. Dissolved oxygen concentrations and its isotopes (δ18ODO) ranged from 0.02 to 0.06 mmol · L-1 and from +9.6‰ to +23.4‰. The δ18ODO proved to be more sensitive than concentration measurements in response to metabolic variation and registered earlier shifts to dominance by respiration. Oxygen (O2) contents in the headspace and its isotopes (δ18OO2) ranged from 2.62 to 3.20 mmol · L-1 and from +9.8‰ to +21.9‰. Headspace samples showed less fluctuations in concentration and isotope trends because aquatic processes were hardly able to alter signals once the gas had reached the headspace. Headspace δ18OO2 values were corrected for gas-water equilibration and were determined to be higher than the mean δ18OH2O of -8.7‰. This finding suggests that counteracting respiration was important even during the highest photosynthetic activity. Additionally, headspace analyses led to the definition of a fractionation factor for respiration (αR) of this cyanobacterium with a value of 0.980. This value confirms the one commonly used for cyanobacteria. Our findings may become important for the management of water bodies where decreases in DO are caused by cyanobacteria.

Universal inter-molecular radical transfer reactions on metal surfaces.

On-surface synthesis provides tools to prepare low-dimensional supramolecular structures. Traditionally, reactive radicals are a class of single-electron species, serving as exceptional electron-withdrawing groups. On metal surfaces, however, such species are affected by conduction band screening effects that may even quench their unpaired electron characteristics. As a result, radicals are expected to be less active, and reactions catalyzed by surface-stabilized radicals are rarely reported. Herein, we describe a class of inter-molecular radical transfer reactions on metal surfaces. With the assistance of aryl halide precursors, the coupling of terminal alkynes is steered from non-dehydrogenated to dehydrogenated products, resulting in alkynyl-Ag-alkynyl bonds. Dehalogenated molecules are fully passivated by detached hydrogen atoms. The reaction mechanism is unraveled by various surface-sensitive technologies and density functional theory calculations. Moreover, we reveal the universality of this mechanism on metal surfaces. Our studies enrich the on-surface synthesis toolbox and develop a pathway for producing low-dimensional organic materials.

Risk factors and prevalence of ramp lesions in ACL ruptures: An analysis from the registry of the Francophone Arthroscopic Society.

PURPOSE: The study aimed to estimate the prevalence of ramp lesions among patients undergoing anterior cruciate ligament (ACL) reconstruction and identify risk factors associated with these lesions. METHODS: A retrospective, multicentre cohort study was conducted using data from the Francophone Arthroscopic Society's registry, including 5359 patients who underwent ACL reconstruction (ACLR) from June 2020 to June 2023. Potential risk factors for ramp lesion such as patient demographics, revision surgery, pivot shift, side-to-side anteroposterior laxity, medial collateral ligament (MCL) injury, lateral meniscal tear and the volume of ligament remnant were evaluated using multivariate regression analyses. BMI and delay to surgery were also assessed. RESULTS: Ramp lesions were identified in 822 patients (15.3%). Univariate analysis identified male sex, younger age, revision surgery, lateral meniscal injury, percentage of ACL remnant (all p < 0.0001) and pivot shift (p = 0.0103) as significant risk factors. MCL injury was associated with a lower risk (p < 0.0001). In multivariate analysis, male sex, younger age, revision surgery, lateral meniscal injury and percentage of ACL remnants remained significant risk factors, while MCL injury remained a protective factor. The anteroposterior laxity wasn't a significant predictor in either analysis. In subgroup analysis, there were differences concerning body mass index (n.s) and the delay to surgery (n.s). CONCLUSION: The study identified male sex, younger age, revision surgery, lateral meniscal injury and pourcentage of ACL remnant as significant risk factors for ramp lesions, with MCL injury acting as a protective factor. This will help regarding the suspicion and identification of ramp lesions. LEVEL OF EVIDENCE: Level III.

The relevance of knee arthroscopy photographs in medicolegal proceedings.

PURPOSE: Whether photographs included in the operative report of knee arthroscopies can make the surgeon liable in the event of a legal investigation remains unknown. The main objective of this study was to establish inter-observer reliability in determining the presence or absence of lesions of the cartilage, meniscus and anterior cruciate ligament (ACL). Secondary objective was to assess the inter-observer reliability in classifying lesions. METHOD: A retrospective observational study was conducted in a continuous serie of 60 patients who underwent knee arthroscopy from the same operator. The photographs of each patient's operative report were presented separately to three experts, blinded to each other. Each expert had to decide on the presence or absence of injuries to the following structures: meniscal, cartilage and ACL and then, classify it. Primary and secondary endpoints were evaluated using the Fleiss' kappa index. RESULTS: Inter-observer reliability for lesion detection was between 0.4 and 0.61 for all structures with three exceptions: for cartilage, it was low (0.15) at the lateral tibial plateau and poor (-0.01) at the external condyle. On the contrary, the concordance was almost perfect (0.8) for the ACL. For classifying cartilaginous and meniscal lesions, inter-observer reliability was poor (from 0.03 to 0.14), except for at the lateral meniscus (0.65). CONCLUSION: Inter-observer reliability of arthroscopic knee diagnoses is poor when photographs alone are used. In the event of a legal investigation following knee arthroscopy, the photographs included in the operative report should not be used alone to hold the surgeon liable.

Enhancing Haloarene Coupling Reaction Efficiency on an Oxide Surface by Metal Atom Addition.

The bottom-up synthesis of carbon-based nanomaterials directly on semiconductor surfaces allows for the decoupling of their electronic and magnetic properties from the substrates. However, the typically reduced reactivity of such nonmetallic surfaces adversely affects the course of these reactions. Here, we achieve a high polymerization yield of halogenated polyphenyl molecular building blocks on the semiconducting TiO2(110) surface via concomitant surface decoration with cobalt atoms, which catalyze the Ullmann coupling reaction. Specifically, cobalt atoms trigger the debromination of 4,4″-dibromo-p-terphenyl molecules on TiO2(110) and mediate the formation of an intermediate organometallic phase already at room temperature (RT). As the debromination temperature is drastically reduced, homocoupling and polymerization readily proceed, preventing presursor desorption from the substrate and entailing a drastic increase of the poly-para-phenylene polymerization yield. The general efficacy of this mechanism is shown with an iodinated terphenyl derivative, which exhibits similar dehalogenation and reaction yield.

Deceptive orbital confinement at edges and pores of carbon-based 1D and 2D nanoarchitectures.

The electronic structure defines the properties of graphene-based nanomaterials. Scanning tunneling microscopy/spectroscopy (STM/STS) experiments on graphene nanoribbons (GNRs), nanographenes, and nanoporous graphene (NPG) often determine an apparent electronic orbital confinement into the edges and nanopores, leading to dubious interpretations such as image potential states or super-atom molecular orbitals. We show that these measurements are subject to a wave function decay into the vacuum that masks the undisturbed electronic orbital shape. We use Au(111)-supported semiconducting gulf-type GNRs and NPGs as model systems fostering frontier orbitals that appear confined along the edges and nanopores in STS measurements. DFT calculations confirm that these states originate from valence and conduction bands. The deceptive electronic orbital confinement observed is caused by a loss of Fourier components, corresponding to states of high momentum. This effect can be generalized to other 1D and 2D carbon-based nanoarchitectures and is important for their use in catalysis and sensing applications.

On-Surface Isomerization of Indigo within 1D Coordination Polymers.

Natural products are attractive components to tailor environmentally friendly advanced new materials. We present surface-confined metallosupramolecular engineering of coordination polymers using natural dyes as molecular building blocks: indigo and the related Tyrian purple. Both building blocks yield identical, well-defined coordination polymers composed of (1 dehydroindigo : 1 Fe) repeat units on two different silver single crystal surfaces. These polymers are characterized atomically by submolecular resolution scanning tunnelling microscopy, bond-resolving atomic force microscopy and X-ray photoelectron spectroscopy. On Ag(100) and on Ag(111), the trans configuration of dehydroindigo results in N,O-chelation in the polymer chains. On the more inert Ag(111) surface, the molecules additionally undergo thermally induced isomerization from the trans to the cis configuration and afford N,N- plus O,O-chelation. Density functional theory calculations confirm that the coordination polymers of the cis-isomers on Ag(111) and of the trans-isomers on Ag(100) are energetically favoured. Our results demonstrate post-synthetic linker isomerization in interfacial metal-organic nanosystems.

MRI sequences at different degrees of flexion to investigate knee popping: an unusual way to diagnose an isolated pigmented villonodular synovitis lesion.

Knee popping is a frequent symptom among knee disorders which requires further investigation in case of a recent evolution of the symptom or pathological associated ones. This article reports a rare presentation of pigmented villonodular synovitis (PVNS), identified as the cause of knee popping symptoms, by performing MRI sequences at various degrees of knee flexion for a patient complaining from a gradual onset of knee popping, occurring when bending the knee over 120° of flexion. MRI sequences were performed just before the popping occurs (flexion 90°) and right after it had occurred (flexion 120°). The latter confirmed the origin of the symptom as the lesion moved forward, passing brutally through the interstice between the PCL and the ACL at 120° of flexion, explaining the popping. Treatment decision was to perform an arthroscopic resection of the lesion. Diagnosis of isolated PVNS was confirmed after anatomopathological analysis.

The role of aromaticity in the cyclization and polymerization of alkyne-substituted porphyrins on Au(111).

Aromaticity is an established and widely used concept for the prediction of the reactivity of organic molecules. However, its role remains largely unexplored in on-surface chemistry, where the interaction with the substrate can alter the electronic and geometric structure of the adsorbates. Here we investigate how aromaticity affects the reactivity of alkyne-substituted porphyrin molecules in cyclization and coupling reactions on a Au(111) surface. We examine and quantify the regioselectivity in the reactions by scanning tunnelling microscopy and bond-resolved atomic force microscopy at the single-molecule level. Our experiments show a substantially lower reactivity of carbon atoms that are stabilized by the aromatic diaza[18]annulene pathway of free-base porphyrins. The results are corroborated by density functional theory calculations, which show a direct correlation between aromaticity and thermodynamic stability of the reaction products. These insights are helpful to understand, and in turn design, reactions with aromatic species in on-surface chemistry and heterogeneous catalysis.

Arthroscopic Posterior Bankart Repair Using the Wilmington Portal to Facilitate Suture Anchor Implantation.

Posterior shoulder instability (PSI) accounts for 2% to 10% of all shoulder instability, with recurrent posterior subluxation being the most common type. One of the most important risk factors is the presence of an anterior humeral notch (so-called reverse Hill-Sachs lesion), and the most common lesion in PSI is a posterior labral lesion. When conservative treatment fails, surgery is recommended to provide long-term stability, manage pain, and enable a return to previous activity levels. Most posterior labral tears are treated by an arthroscopic posterior Bankart procedure. Visualization of the posterior aspect of the glenohumeral joint is technically challenging in this procedure. The instrumental portal is also a matter of concern because there is no rotator interval posteriorly for cannula placement. The purpose of this article is to propose a technique using a secondary posterolateral Wilmington instrumental portal to perform easy and reproducible placement of the posterior suture anchor at a 45° angle to the glenoid rim. We recommend implementing this technique in patients with painful PSI or with a type B2 lesion according to the Moroder classification.

Insufficient evidence to confirm benefit of adjuvant distal clavicle resection during rotator cuff repair: a systematic review and meta-analysis.

The aim of this study is to determine whether adjuvant Distal Clavicle Resection (DCR) improves outcomes of Rotator Cuff Repair (RCR) in terms of ROM, clinical scores as well as reducing complications and/or reoperations. This systematic review conforms to the PRISMA guidelines. Studies were included if they compared outcomes of RCR with and without adjuvant DCR and reported on postoperative ROM, clinical scores, complications, and/or reoperations. Seven studies that comprised 1572 shoulders which underwent RCR at a follow-up ranged 8-54 months: 398 with adjuvant DCR and 1174 without DCR. No significant differences were found between patients that had DCR versus those that did not have DCR, in terms of postoperative clinical scores (ASES, Constant, pVAS), postoperative ROM (AFE, external and internal rotation), retear rate and reoperation rate. There were no significant differences in ROM, clinical scores, or rates of retears and reoperations between patients that underwent RCR with or without adjuvant DCR. There is insufficient evidence to support routine DCR during RCR; the incidence of new or residual acromioclavicular joint (ACJ) pain after RCR with adjuvant DCR is higher than following isolated RCR, which could in fact induce iatrogenic morbidity and therefore does not justify the additional surgery time and costs of routine adjuvant DCR.

Photoresponse of Solution-Synthesized Graphene Nanoribbon Heterojunctions on Diamond Indicating Phototunable Photodiode Polarity.

Graphene nanoribbon heterostructures and heterojunctions have attracted interest as next-generation molecular diodes with atomic precision. Their mass production via solution methods and prototypical device integration remains to be explored. Here, the bottom-up solution synthesis and characterization of liquid-phase-processable graphene nanoribbon heterostructures (GNRHs) are demonstrated. Joint photoresponsivity measurements and simulations provide evidence of the structurally defined heterostructure motif acting as a type-I heterojunction. Real-time, time-dependent density functional tight-binding simulations further reveal that the photocurrent polarity can be tuned at different excitation wavelengths. Our results introduce liquid-phase-processable, self-assembled heterojunctions for the development of nanoscale diode circuitry and adaptive hardware.

On-Surface Synthesis of Polyphenylene Wires Comprising Rigid Aliphatic Bicyclo[1.1.1]Pentane Isolator Units.

Bicyclo[1.1.1]pentane (BCP) motifs are of growing importance to the pharmaceutical industry as sp3 -rich bioisosteres of benzene rings and as molecular building blocks in materials science. Herein we explore the behavior of 1,3-disubstituted BCP moieties on metal surfaces by combining low-temperature scanning tunneling microscopy / non-contact atomic force microscopy studies with density functional theory modeling. We examine the configuration of individual BCP-containing precursors on Au(111), their supramolecular assembly and thermally activated dehalogenative coupling reactions, affording polymeric chains with incorporated electronically isolating units. Our studies not only provide the first sub-molecular insights of the BCP scaffold behavior on surfaces, but also extend the potential application of BCP derivatives towards integration in custom-designed surface architectures.

On-surface synthesis of enetriynes.

Belonging to the enyne family, enetriynes comprise a distinct electron-rich all-carbon bonding scheme. However, the lack of convenient synthesis protocols limits the associated application potential within, e.g., biochemistry and materials science. Herein we introduce a pathway for highly selective enetriyne formation via tetramerization of terminal alkynes on a Ag(100) surface. Taking advantage of a directing hydroxyl group, we steer molecular assembly and reaction processes on square lattices. Induced by O2 exposure the terminal alkyne moieties deprotonate and organometallic bis-acetylide dimer arrays evolve. Upon subsequent thermal annealing tetrameric enetriyne-bridged compounds are generated in high yield, readily self-assembling into regular networks. We combine high-resolution scanning probe microscopy, X-ray photoelectron spectroscopy and density functional theory calculations to examine the structural features, bonding characteristics and the underlying reaction mechanism. Our study introduces an integrated strategy for the precise fabrication of functional enetriyne species, thus providing access to a distinct class of highly conjugated π-system compounds.

Early Ultrastructural Changes in Biopsies From Patients With Symptomatic CKD of Uncertain Etiology.

Introduction: Although the investigation of chronic kidney disease of uncertain etiology (CKDu) has identified many possible influencing factors in recent years, the exact pathomechanism of this disease remains unclear. Methods: In this study, we collected 13 renal biopsies from patients with symptomatic CKDu (Sym-CKDu) from Sri Lanka with well-documented clinical and socioeconomic factors. We performed light microscopy and electron microscopic evaluation for ultrastructural analysis, which was compared with 100 biopsies from German patients with 20 different kidney diseases. Results: Of the 13 Sri Lankan patients, 12 were men (92.3%), frequently employed in agriculture (50%), and experienced symptoms such as feeling feverish (83.3%), dysuria (83.3%), and arthralgia (66.6%). Light microscopic evaluation using activity and chronicity score revealed that cases represented early stages of CKDu except for 2 biopsies, which showed additional signs of diabetes. Most glomeruli showed only mild changes, such as podocyte foot process effacement on electron microscopy. We found a spectrum of early tubulointerstitial changes including partial loss of brush border in proximal tubules, detachment of tubular cells, enlarged vacuoles, and mitochondrial swelling associated with loss of cristae and dysmorphic lysosomes with electron-dense aggregates. None of these changes occurred exclusively in Sym-CKDu; however, they were significantly more frequent in these cases than in the control cohort. Conclusion: In conclusion, our findings confirm the predominant and early alterations of tubular structure in CKDu that can occur without significant glomerular changes. The ultrastructural changes do not provide concrete evidence of the cause of CKDu but were significantly more frequent in Sym-CKDu than in the controls.

Electronic band structure of 1D π-d hybridized narrow-gap metal-organic polymers.

One-dimensional (1D) metal-organic (MO) nanowires are captivating from fundamental and technological perspectives due to their distinctive magnetic and electronic properties. The solvent-free synthesis of such nanomaterials on catalytic surfaces provides a unique approach for fabricating low-dimensional single-layer materials with atomic precision and low amount of defects. A detailed understanding of the electronic structure of MO polymers such as band gap and dispersive bands is critical for their prospective implementation into nanodevices such as spin sensors or field-effect transistors. Here, we have performed the on-surface reaction of quinoidal ligands with single cobalt atoms (Co-QDI) on a vicinal Au(788) surface in ultra-high vacuum. This procedure promotes the growth and uniaxial alignment of Co-QDI MO chains along the surface atomic steps, while permitting the mapping of their electronic properties with space-averaging angle-resolved photoemission spectroscopy. In the direction parallel to the principal chain axis, a well-defined 1D band structure with weakly dispersive and dispersive bands is observed, confirming a pronounced electron delocalization. Low-temperature scanning tunneling microscopy/spectroscopy delves into the atomically precise structure of the nanowires and elucidates their narrow bandgap. These findings are supported with GW0 band structure calculations showing that the observed electronic bands emanate from the efficient hybridization of Co(3d) and molecular orbitals. Our work paves the way towards a systematic search of similar 1D π-d hybridized MO chains with tunable electronic and magnetic properties defined by the transition or rare earth metal atom of choice.