91 research outputs found
Quantification of Malalignment and Corrective Osteotomies in Patients With Malunion After Elastic Stable Intramedullary Nailing of Pediatric Forearm Fractures
PURPOSE: This study looked at postoperative malunion with restricted function after elastic stable intramedullary nailing (ESIN) in pediatric patients in their childhood or adolescence. The primary objective was to compare the magnitude of the osseous malposition to the healthy opposite side. Second, these individuals were treated with patient-specific surgical instrumentation, and functional outcomes were documented.
METHODS: Patients under the age of 18 at the time of a corrective osteotomy due to a forearm malunion after initial ESIN treatment were included in this study. The healthy contralateral side was used as a reference for preoperative analysis and planning of the osteotomy. Osteotomies were performed using patient-specific guides and the direction and extent of the malunion were compared to the change in range of motion (ROM) after the operation.
RESULTS: Fifteen patients met the inclusion criteria at three years after initial ESIN placement, with the most pronounced malposition in the rotational axis. The postoperative function significantly improved by 12° (pre-op: 60° ± 17; post-op: 72° ± 10) of pronation and 33° (pre-op: 43° ± 26; post-op: 76° ± 13) of supination. There was no correlation between the amount and direction of malformation and the change in ROM.
CONCLUSIONS: The most noticeable malunion after forearm fractures treated with the ESIN technique is in the rotational direction. Patient-specific corrective osteotomy of pediatric forearm malunion following forearm fracture fixation with ESIN achieves significant improvement in forearm range of motion.
CLINICAL RELEVANCE: The findings are clinically relevant since forearm fractures are the most common pediatric fracture, affecting a large number of patients who can benefit from the findings of this study. It has the potential to raise awareness of the significance of the accurate rotational component of intraoperative bone alignment in the ESIN procedure
3D analysis of the distal ulna with regard to the design of a new ulnar head prosthesis
STUDY DESIGN
A retrospective, single center, data analysis.
OBJECTIVE
Persistent pain and instability are common complications after distal ulnar head arthroplasty. One main reason may be the insufficient representation of the anatomical structures with the prosthesis. Some anatomical structures are neglected such as the ulnar head offset and the ulnar torsion which consequently influences the wrist biomechanics.
METHODS
CT scans of the ulnae of forty healthy and asymptomatic patients were analyzed in a three-dimensional surface calculation program. In the best fit principle, cylinders were fitted into the medullary canal of the distal ulna and the ulnar head to determine their size. The distance between the central axes of the two cylinders was measured, which corresponds to the ulnar offset, and also their rotational orientation was measured, which corresponds to the ulnar torsion.
RESULTS
The mean medullary canal diameter was 5.8 mm (±0.8), and the ulnar head diameter was 15.8 mm (±1.5). The distance between the two cylinder axes was 3.89 mm (±0.78). The orientation of this offset was at an average of 8.63° (±15.28) of supination, reaching from 23° pronation to 32° supination.
CONCLUSION
With these findings, a novel ulnar head prosthesis should have different available stem and head sizes but also have an existing but variable offset between these two elements. A preoperative three-dimensional analysis is due to the high variation of offset orientation highly recommended. These findings might help to better represent the patients natural wrist anatomy in the case of an ulnar head arthroplasty.
LEVEL OF EVIDENCE
III
3D planning and patient specific instrumentation for intraarticular corrective osteotomy of trapeziometacarpal-, metacarpal and finger joints
BACKGROUND
Intra-articular malunions of the finger can lead to deformity and loss of function and can be treated with intra-articular corrective osteotomies. The aim of this study was to evaluate radiographic joint congruency, feasibility and functional outcome of three-dimensional (3D) printed patient-specific instrumentation (PSI) for corrective osteotomies at the trapeziometacarpal and finger joints.
METHODS
Computer-tomography (CT) scans were acquired preoperatively for standard 3D planning, which was followed by calculation of cutting planes and the design of individualized bone surface contact drilling, sawing and reposition guides. Follow-up CT scans and clinical examinations (range of motion, grip strength) were performed. Postoperative complications were documented and patient-reported outcome measurements were assessed (Single Assessment Numeric Evaluation (SANE) score, brief Michigan Hand Questionnaire (MHQ)).
RESULTS
Ten patients (mean age 28.4 ± 12.8,range 13.8-51.3) years) were included with a mean follow-up of 21 ± 18 (3-59) months including seven osteotomies at the trapeziometacarpal or metacarpophalangeal joints and three at the proximal interphalangeal joint (PIP). All radiographic follow-up examinations showed the planned correction with good joint congruency and regular osseous consolidation. At the latest follow-up, the range of motion (ROM) increased and the average grip strength recovered to the level of the contralateral side. No postoperative complication was detected. The mean SANE score improved from 44 ± 23 (0-70) to 82 ± 12 (60-90) after a mean of 72 ± 20 (44-114) months. The mean postoperative brief MHQ was 92 ± 8 (71-98).
CONCLUSION
The use of 3D PSI in treating intra-articular malunions at the trapeziometacarpal and finger joints restored articular congruency accurately. ROM and grip strength improved postoperatively comparable to the healthy contralateral side and patient-reported outcome measures improved after medium-term follow-up
Distinct Clinical and Laboratory Patterns of Pneumocystis jirovecii Pneumonia in Renal Transplant Recipients.
Late post-transplant Pneumocystis jirovecii pneumonia (PcP) has been reported in many renal transplant recipients (RTRs) centers using universal prophylaxis. Specific features of PcP compared to other respiratory infections in the same population are not well reported. We analyzed clinical, laboratory, administrative and radiological data of all confirmed PcP cases between January 2009 and December 2014. To identify factors specifically associated with PcP, we compared clinical and laboratory data of RTRs with non-PcP. Over the study period, 36 cases of PcP were identified. Respiratory distress was more frequent in PcP compared to non-PcP (tachypnea: 59%, 20/34 vs. 25%, 13/53, p = 0.0014; dyspnea: 70%, 23/33 vs. 44%, 24/55, p = 0.0181). In contrast, fever was less frequent in PcP compared to non-PcP pneumonia (35%, 11/31 vs. 76%, 42/55, p = 0.0002). In both cohorts, total lymphocyte count and serum sodium decreased, whereas lactate dehydrogenase (LDH) increased at diagnosis. Serum calcium increased in PcP and decreased in non-PcP. In most PcP cases (58%, 21/36), no formal indication for restart of PcP prophylaxis could be identified. Potential transmission encounters, suggestive of interhuman transmission, were found in 14/36, 39% of patients. Interhuman transmission seems to contribute importantly to PcP among RTRs. Hypercalcemia, but not elevated LDH, was associated with PcP when compared to non-PcP
Seeing the Whole Picture. Towards a Multi-perspective Approach to News Content Diversity based on Liberal and Deliberative Models of Democracy
By providing diverse news content, news media are key for a well-functioning public sphere. However, agreement on how to measure news content diversity is lacking. Research often refers to democratic theory as normative reference point, but different models of democracy understand news content diversity differently. Our study makes a unique, innovative contribution to this field: (1) We develop a methodological framework for measuring news content diversity, that is a set of comprehensive measuring instruments that derive different operationalizations of topic and actor diversity each from liberal and deliberative democratic theories. (2) Considering that a good public discourse requires more than diversity, we analyze news content diversity in the context of four other journalistic standards: neutrality, rationality, discursivity, and civility. (3) We prove the applicability of our measuring instruments by means of a standardized content analysis of six German news media as a case study. The different quality profiles of these outlets our analysis reveals are explained by their different functions in the media system. Our study shows how important a multi-perspectival normative approach to news content diversity is, both empirically and theoretically. Future studies on news content diversity should make their normative foundations transparent and derive their indicators purposefully therefrom
Fairness: plurality, causality, and insurability
This article summarizes the main topics, findings, and avenues for future work from the workshop Fairness with a view towards insurance held August 2023 in Copenhagen, Denmark
Somatic therapy of a mouse SMA model with a U7 snRNA gene correcting SMN2 splicing
Spinal Muscular Atrophy (SMA) is due to the loss of SMN1 gene function. The duplicate gene SMN2 produces some, but not enough, SMN protein because most transcripts lack exon 7. Thus, promoting the inclusion of this exon is a therapeutic option. We show that a somatic gene therapy using the gene for a modified U7 RNA which stimulates this splicing has a profound and persistent therapeutic effect on the phenotype of a severe SMA mouse model. To this end, the U7 gene and vector and the production of pure, highly concentrated self-complementary (sc) AAV9 vector particles were optimized. Introduction of the functional vector into motoneurons of newborn SMA mice by intracerebroventricular injection led to a highly significant, dose-dependent increase in life span and improvement of muscle functions. Besides the central nervous system, the therapeutic U7 RNA is expressed in the heart and liver which may additionally contribute to the observed therapeutic efficacy. This approach provides an additional therapeutic option for SMA and could also be adapted to treat other diseases of the central nervous systems with regulatory small RNA genes
A decade of monitoring micropollutants in urban wet-weather flows: What did we learn?
Urban wet-weather discharges from combined sewer overflows (CSO) and stormwater outlets (SWO) are a potential pathway for micropollutants (trace contaminants) to surface waters, posing a threat to the environment and possible water reuse applications. Despite large efforts to monitor micropollutants in the last decade, the gained information is still limited and scattered. In a metastudy we performed a data-driven analysis of measurements collected at 77 sites (683 events, 297 detected micropollutants) over the last decade to investigate which micropollutants are most relevant in terms of 1) occurrence and 2) potential risk for the aquatic environment, 3) estimate the minimum number of data to be collected in monitoring studies to reliably obtain concentration estimates, and 4) provide recommendations for future monitoring campaigns. We highlight micropollutants to be prioritized due to their high occurrence and critical concentration levels compared to environmental quality standards. These top-listed micropollutants include contaminants from all chemical classes (pesticides, heavy metals, polycyclic aromatic hydrocarbons, personal care products, pharmaceuticals, and industrial and household chemicals). Analysis of over 30,000 event mean concentrations shows a large fraction of measurements (> 50%) were below the limit of quantification, stressing the need for reliable, standard monitoring procedures. High variability was observed among events and sites, with differences between micropollutant classes. The number of events required for a reliable estimate of site mean concentrations (error bandwidth of 1 around the “true" value) depends on the individual micropollutant. The median minimum number of events is 7 for CSO (2 to 31, 80%-interquantile) and 6 for SWO (1 to 25 events, 80%-interquantile). Our analysis indicates the minimum number of sites needed to assess global pollution levels and our data collection and analysis can be used to estimate the required number of sites for an urban catchment. Our data-driven analysis demonstrates how future wet-weather monitoring programs will be more effective if the consequences of high variability inherent in urban wet-weather discharges are considered
Magnetic cluster excitations in the antiferromagnetic phase of a-MnMoO4
The tetramer-based compound a-MnMoO4 exhibits four prominent peaks in the inelastic neutron scattering
(INS) spectrum between 0.5 and 2.0 meV below 10 K. They are assigned to magnetic excitations of the
(Mn2+)4 rhombus shaped cluster, with resulting values of the exchange parameters J= +0.051 meV and J= -0.019 meV along the edges and the short diagonal, respectively. The interactions within the tetramer are
treated exactly in an isotropic quantum mechanical model leading to an S510 cluster ground state. The weaker
antiferromagnetic (AFM) intercluster interactions, Jint = -4.5*10-3 meV, are treated in a molecular-field
model below the AFM transition temperature TN= 10.7 K. INS and susceptibility are in quantitative agreement
with this approach
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