Complex fractures of the distal humerus in the elderly: Is primary total elbow arthroplasty a valid treatment alternative? A series of 20 cases

SummaryIntroductionDistal humerus fractures are fairly rare. But as our population ages, these fractures become more complex and the choice of treatment more delicate. Poor bone quality results in many technical problems and the fixation hardware stability remains at risk. The goal of this study was to evaluate the functional recovery and morbidity of complex distal humerus fractures in elderly patients when treated with elbow prosthesis.HypothesisGood functional recovery can be achieved with a total joint replacement.Patients and methodsThis series consisted of 20 patients (18 women and two men) having an average age of 80years (range 65–93, median 80). Based on the AO classification, there were two Type A2 fractures, two Type B fractures, 15 Type C fractures and one fracture that could not be classified because of previous rheumatoid disease history at this elbow. Two fractures were open. In two cases, the olecranon was also fractured. Treatment consisted of the implantation of a Coonrad-Morrey, hinge-type total elbow prosthesis (Zimmer®, Warsaw, IN, USA). The Mayo Clinic surgical approach was used 17 times and the transolecranon approach was used three times. Primary arthroplasty was performed in 19 cases and the surgery was performed after six weeks of conservative treatment (diagnostic delay) in one case. Unrestricted motion was allowed after surgery, but a maximum of 0.5kg could be carried during the first 3months; this was subsequently increased to 2.5kg.ResultsFifteen of the 20 patients were available for reevaluation with an average follow-up of 3.6years (range 1.7–5.5, median 3.4). Four patients had died and one was lost to follow-up. The average range of motion was 97° (range 60–130°), comprising an average flexion of 130° (range 110–140°) and average loss of extension of 33° (range 0–80°). Pronation and supination were normal. The average Mayo Elbow Performance Score (MEPS) was 83 (range 60–100, median 80). X-rays revealed seven cases of radiolucent lines, with two being progressive. There was no visible wear of the polyethylene bushings at the hinge. Six patients had moderate periarticular heterotopic ossification. The two cases of olecranon osteotomy and one case of olecranon fracture had healed. There were no surgical site infections but two cases of ulnar compression, one of which required neurolysis. There was one case of humeral component loosening after 6years, but the implant was not changed.DiscussionThe clinical range of motion results were comparable to published data. The functional scores were slightly lower, mainly because of the pain factor. The initial results were encouraging and consistent with published data as long as the indications were well-chosen. Based on this retrospective study, total elbow arthroplasty can be a valid alternative in the surgeon's treatment armamentarium for complex distal humerus fractures in elderly patients who have moderate functional demands. Our results support our hypothesis, since we found good functional recovery without associated morbidity.Level of evidenceLevel IV retrospective study without comparator

Thermal emission from the Earth-sized exoplanet TRAPPIST-1 b using JWST

The TRAPPIST-1 system is remarkable for its seven planets that are similar in size, mass, density, and stellar heating to the rocky planets Venus, Earth, and Mars in our own Solar System (Gillon et al. 2017). All TRAPPIST-1 planets have been observed with the transmission spectroscopy technique using the Hubble or Spitzer Space Telescopes, but no atmospheric features have been detected or strongly constrained (Ducrot et al. 2018; de Wit et al. 2018; Zhang et al. 2018; Garcia et al. 2022). TRAPPIST-1 b is the closest planet to the system's M dwarf star, and it receives 4 times as much irradiation as Earth receives from the Sun. This relatively large amount of stellar heating suggests that its thermal emission may be measurable. Here we present photometric secondary eclipse observations of the Earth-sized TRAPPIST-1 b exoplanet using the F1500W filter of the MIRI instrument on JWST. We detect the secondary eclipse in each of five separate observations with 8.7-sigma confidence when all data are combined. These measurements are most consistent with the re-radiation of the TRAPPIST-1 star's incident flux from only the dayside hemisphere of the planet. The most straightforward interpretation is that there is little or no planetary atmosphere redistributing radiation from the host star and also no detectable atmospheric absorption from carbon dioxide (CO$_2$) or other species.Comment: Submitted to Natur

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Identification of target-specific bioisosteric fragments from ligand-protein crystallographic data

Bioisosteres are functional groups or atoms that are structurally different but that can form similar intermolecular interactions. Potential bioisosteres were identified here from analysing the X-ray crystallographic structures for sets of different ligands complexed with a fixed protein. The protein was used to align the ligands with each other, and then pairs of ligands compared to identify substructural features with high volume overlap that occurred in approximately the same region of geometric space. The resulting pairs of substructural features can suggest potential bioisosteric replacements for use in lead-optimisation studies. Experiments with 12 sets of ligand-protein complexes from the Protein Data Bank demonstrate the effectiveness of the procedure

The role of angiography in the congruence of cardiovascular measurements between autopsy and postmortem imaging.

Postmortem CT angiography is the method of choice for the postmortem imaging investigations of the cardiovascular (CV) system. However, autopsy still remains the gold standard for CV measurement. Nevertheless, there are not any studies on CV measurements on the multi-phase postmortem angiography (MPMCTA) which includes comparisons with autopsy. Therefore, the aim of this study is to compare CV measurements between the native CT scan and the three phases of the MPMCTA to find out which of these modalities correlate the best with autopsy measurements. For this study, we selected retrospectively 50 postmortem cases that underwent both MPMCTA and autopsy. A comparison was carried out between the CV measurements obtained with imaging (aorta; heart cavities and cardiac wall thicknesses; maximum cardiac diameter and cardiothoracic ratio) and at the autopsy (aorta; cardiac valves, ventricular thicknesses, and weight). Our results show that the dynamic phase displays an advantage for the measurement of the aortas. However, the MPMCTA is not accurate to measure the cardiac wall thicknesses. The measurements of the heart cavities show no correlation with the heart valves. The cardiothoracic ratio measured by the MPMCTA shows no correlation with the heart weight. Nevertheless, the maximum cardiac diameter exhibits a correlation with the latter on the venous and dynamic phase. These results show that only few CV parameters measured with imaging correlate with measurement obtained at the autopsy. These results indicate that in order to better estimate values obtained at the autopsy, we need to define new reference values for the CV measurement on MPMCTA

In search of lost hybridity: the French Daniel Deronda

Starting from a set of examples of borrowings from French in George Eliot’s Daniel Deronda, I explore the various ways in which the characters’ and narrator’s use of mixed English–French utterances generates inferences which make the transcending of their mono-cultural self possible. I go on to argue that in Jumeau’s recent French translation of the novel, the reader is not given access to those inferences, resulting in the erasing of an Anglo-European, cosmopolitan identity

No thick carbon dioxide atmosphere on the rocky exoplanet TRAPPIST-1 c

Seven rocky planets orbit the nearby dwarf star TRAPPIST-1, providing a unique opportunity to search for atmospheres on small planets outside the Solar System (Gillon et al., 2017). Thanks to the recent launch of JWST, possible atmospheric constituents such as carbon dioxide (CO2) are now detectable (Morley et al., 2017, Lincowski et al., 2018}. Recent JWST observations of the innermost planet TRAPPIST-1 b showed that it is most probably a bare rock without any CO2 in its atmosphere (Greene et al., 2023). Here we report the detection of thermal emission from the dayside of TRAPPIST-1 c with the Mid-Infrared Instrument (MIRI) on JWST at 15 micron. We measure a planet-to-star flux ratio of fp/fs = 421 +/- 94 parts per million (ppm) which corresponds to an inferred dayside brightness temperature of 380 +/- 31 K. This high dayside temperature disfavours a thick, CO2-rich atmosphere on the planet. The data rule out cloud-free O2/CO2 mixtures with surface pressures ranging from 10 bar (with 10 ppm CO2) to 0.1 bar (pure CO2). A Venus-analogue atmosphere with sulfuric acid clouds is also disfavoured at 2.6 sigma confidence. Thinner atmospheres or bare-rock surfaces are consistent with our measured planet-to-star flux ratio. The absence of a thick, CO2-rich atmosphere on TRAPPIST-1 c suggests a relatively volatile-poor formation history, with less than 9.5 +7.5 -2.3 Earth oceans of water. If all planets in the system formed in the same way, this would indicate a limited reservoir of volatiles for the potentially habitable planets in the system.Comment: Published in Nature on June 19th. 2023, 10 figures, 4 table