The anterior impingement after mobile-bearing unicomparimental knee arthroplasty—a neglected problem. A clinical report of 14 cases

BACKGROUND: Mobile-bearing unicompartmental knee arthroplasty (MB-UKA) is a proven implant that has reliably delivered excellent results for decades. Based on the constrained implant design in MB-UKA, the occasional occurrence of anterior impingement should be expected. However, surprisingly, there are no clinical reports. METHODS: From 2016 to 2020, 14 patients with anterior medial knee pain were admitted to our arthroplasty center after MB-UKA implantation elsewhere. After taking the medical history and clinical examination, radiological imaging of the implant in at least 2 planes, including a whole-leg anteroposterior view, was performed. The “Knee Society Score (KSS)” and the “Knee Injury and Osteoarthritis Outcome Score (KOOS)” were recorded. Anterior impingement was diagnosed by reviewing the typical findings and specific exclusion of other diagnoses. RESULTS: The 14 patients showed a KSS of 46.6 and a KOOS of 51.5. The average pain level on the “Visual Analog Scale” was 7.8. The positioning of the implants showed consistently noticeable deviations from the standard recommendations. All 14 patients were treated by removing the MB-UKA and changing to a complete TKA. At the 12-month follow-up, the average Visual Analog Scale score was 1.8, and KOOS and KSS were 86 and 82, respectively. CONCLUSIONS: The potential risk of anterior impingement in MB-UKA can be assumed. Diagnosis requires a detailed collection of medical history and clinical details combined with accurate radiological imaging. The cause of anterior impingement in MB-UKA is multifactorial and refers in our small group to the sum of minor deviations in implant positioning compared to the general recommendations

Electronic orders near the type-II van Hove singularity in BC3_3

Using the functional renormalization group, we investigate the electron instability in the single-sheet BC$_3$ when the electron filling is near a type-II van Hove singularity. For a finite Hubbard interaction, the ferromagnetic-like spin density wave order dominates in the immediate vicinity of the singularity. Elsewhere near the singularity the p-wave superconductivity prevails. We also find that a small nearest-neighbor Coulomb repulsion can enhance the superconductivity. Our results show that BC$_3$ would be a promising candidate to realize topological $p+ip'$ superconductivity, but the transition temperature is practically sizable only if the local interaction is moderately strong.Comment: 6 pages, 6 color figures. arXiv admin note: text overlap with arXiv:1503.0047

Calculation of CSP Yields with Probabilistic Meteorological Data Sets: A Case Study in Brazil

AbstractCurrent practice for yield prognosis of solar thermal power plants simulates the average annual performance by using a typical meteorological year data set (TMY). This represents the long-term average or a 50 % probability of exceedance(P50) ofdirect normal irradiance (DNI) at the project's location. For more conservative risk evaluation it is common practice to calculate the 90 % yield exceedance level (P90) by estimating the uncertainty of the long-term DNI which depends on data set uncertainty and inter-annual variability.A simple approach to calculate the P90 yieldis to assume a normal distribution for this uncertaintyand a direct 1:1 relation of DNI averages to the yields. However, since the relation of DNI to energy yield is actually not linear it becomes more and more popular to calculate it from annual meteorological data sets (MY90), which are representing P90 DNI averages at a realistic distribution of actual values in the same time resolution as the P50 TMY. Applying such MY90 data sets still has the shortcoming that they are synthetic, whilereal years of data should lead to more realistic yields. Thus, this paper proposes the use of multiple years of weather inputto realistically include the annual variability of DNI. To also represent the effect of the data set uncertainty,thetime-series are modifiedin such away that the annual DNI values follow a normal distribution with a 1-sigma width equivalent to the diagnosed data set uncertainty. The impact of this probabilistic approach on the energy yield of a CSP project is shown for thesite Bom Jesus da Lapa in Brazil.Since the estimation of a realistic uncertainty of the long-term DNI at this location was challenging, several uncertainties between 3-9 % were assumed that could possibly be inherent in such a data set. Using theseassumed data set uncertainties and theinter-annual variability of the data set, the deviations to the long-term meanof energy yield are shown for the current practice approaches and the new method. Hence for a data set uncertainty of 5 %the very basic risk analysis results in a single-year P90 yield11.1 % below P50,while using a MY90 single year data set is resulting in a P90 yield 9.7 % below P50. The probabilistic approach introduced here is leading to P90 yields 8.5 % below P50

Analysis of a spatial gene expression database for sea anemone Nematostella vectensis during early development

International audienceThe spatial distribution of many genes has been visualized during the embryonic development in the starlet sea anemone Nematostella vectensis in the last decade. In situ hybridization images are available in the Kahi Kai gene expression database, and a method has been developed to quantify spatial gene expression patterns of N. vectensis. In this paper, gene expression quantification is performed on a wide range of gene expression patterns from this database and descriptions of observed expression domains are stored in a separate database for further analysis

Orthogeriatric co-management: differences in outcome between major and minor fractures

PURPOSE: Literature shows that orthogeriatric co-management improves the outcomes of patients with hip fractures. Corresponding research with more diverse fragility fracture groups is lacking. Therefore, an examination was performed prospectively as a 2 year-follow-up on an orthogeriatric co-managed ward, comparing relevant outcome parameters for major and minor fragility fractures. METHODS: All patients treated on an orthogeriatric co-managed ward from February 2014 to January 2015 were included and their injuries, orthogeriatric parameters such as the Barthel Index (BI), Parker Mobility Score (PMS) and place of residence (POR). Patients were separated into two groups of either immobilizing major (MaF) or non-immobilizing minor (MiF) fractures. 2 years later, a follow-up was conducted via telephone calls and questionnaires mailed to patients and/or their relatives. RESULTS: 740 (574 major vs. 166 minor injuries) patients were initially assessed, with a follow-up rate of 78.9%. The in-house, 1-year, and 2-year-mortality rates were 2.7, 27.4, and 39.2%, respectively. Mortality was significantly higher for MaF in the short term, but not after 2 years. On average, during the observation period, patients regained their BI by 36.7 points (95% CI: 33.80–39.63) and PMS was reduced by 1.4 points (95% CI: 1.16–1.68). No significant differences were found in the readmission rate, change in BI, PMS or POR between the MaF and MiF groups. CONCLUSION: The relevance of orthogeriatric treatment to improving functional and socioeconomic outcomes was confirmed. The similarity of the results from both fracture groups emphasizes the need for a multidisciplinary approach also for minor fractures. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00068-022-01974-3

Direct imaging of extra-solar planets in star forming regions: Lessons learned from a false positive around IM Lup

Most exoplanet imagers consist of ground-based adaptive optics coronagraphic cameras which are currently limited in contrast, sensitivity and astrometric precision, but advantageously observe in the near-IR (1- 5{\mu}m). Because of these practical limitations, our current observational aim at detecting and characterizing planets puts heavy constraints on target selection, observing strategies, data reduction, and follow-up. Most surveys so far have thus targeted young systems (1-100Myr) to catch the putative remnant thermal radiation of giant planets, which peaks in the near-IR. They also favor systems in the solar neighborhood (d<80pc), which eases angular resolution requirements but also ensures a good knowledge of the distance and proper motion, which are critical to secure the planet status, and enable subsequent characterization. Because of their youth, it is very tempting to target the nearby star forming regions, which are typically twice as far as the bulk of objects usually combed for planets by direct imaging. Probing these interesting reservoirs sets additional constraints that we review in this paper by presenting the planet search that we initiated in 2008 around the disk-bearing T Tauri star IM Lup (Lupus star forming region, 140-190pc). We show and discuss why age determination, the choice of evolutionary model for the central star and the planet, precise knowledge of the host star proper motion, relative or absolute astrometric accuracy, and patience are the key ingredients for exoplanet searches around more distant young stars. Unfortunately, most of the time, precision and perseverance are not paying off: we discovered a candidate companion around IM Lup in 2008, which we report here to be an unbound background object. We nevertheless review in details the lessons learned from our endeavor, and additionally present the best detection limits ever calculated for IM Lup.Comment: 8 pages, 3 figures, 3 tables, accepted to A&

Plain X-ray is insufficient for correct diagnosis of tibial shaft spiral fractures: a prospective trial

Purpose Tibial shaft spiral fractures and fractures of the distal third of the tibia (AO:42A/B/C and 43A) frequently occur with non-displaced posterior malleolus fractures (PM). This study investigated the hypothesis that plain X-ray is not sufcient for a reliable diagnosis of associated non-displaced PM fractures in tibial shaft spiral fractures. Methods 50 X-rays showing 42A/B/C and 43A fractures were evaluated by two groups of physicians, each group was comprised of a resident and a fellowship-trained traumatologist or radiologist. Each group was tasked to make a diagnosis and/ or suggest if further imaging was needed. One group was primed with the incidence of PM fractures and asked to explicitly assess the PM. Results Overall, 9.13/25 (SD±5.77) PM fractures were diagnosed on X-ray. If the posterior malleolus fracture was named or a CT was requested, the fracture was considered “detected”. With this in mind, 14.8±5.95 posterior malleolus fractures were detected. Signifcantly more fractures were diagnosed/detected (14 vs. 4.25/25; p<0.001/14.8 vs. 10.5/25; p<0.001) in the group with awareness. However, there were signifcantly more false positives in the awareness group (2.5 vs. 0.5; p=0.024). Senior physicians recognized slightly more fractures than residents (residents: 13.0±7.79; senior physicians: 16.5±3.70; p=0.040). No signifcant diferences were demonstrated between radiologists and trauma surgeons. The inner-rater reliability was high with 91.2% agreement. Inter-rater reliability showed fair agreement (Fleiss-Kappa 0.274, p<0.001) across all examiners and moderate agreement (Fleiss-Kappa 0.561, p<0.001) in group 2. Conclusion Only 17% of PM fractures were identifed on plain X-ray and awareness of PM only improved diagnosis by 39%. While experiencing improved accuracy, CT imaging should be included in a comprehensive examination of tibial shaft spiral fractures