Mid- and long-term clinical results of the Elektra and Moovis prosthesis for trapeziometacarpal joint replacement.

BACKGROUND: Total joint arthroplasty as a surgical treatment option for trapeziometacarpal joint arthritis is recently revived. The aim of this study is to report on mid- and long-term results of the Elektra (single-mobility) and Moovis (dual-mobility) prosthesis for treatment of primary thumb carpometacarpal joint arthritis. METHODS: In this retrospective, monocentric, descriptive cohort study, 31 prostheses were evaluated that were implanted by a single surgeon in 26 patients between 2009 and 2019. Indication for surgery was trapeziometacarpal joint osteoarthritis (Eaton/Littler Stage II and III). Clinical and radiological follow-up was performed at a minimum of 24 months. The postoperative assessment included range of motion, pain, strength as well as functional scores (DASH, MHQ). Implant survival and complications were the primary endpoints. RESULTS: 10 Elektra and 21 Moovis prostheses were implanted between 2009 and 2019 with a mean follow-up of 74.2 months in the Elektra and 41.4 months in the Moovis group. The average patients' age at surgery was 64 years. Postoperative pain levels (VAS 0-10) were below 2 at rest and under stress in both groups. Grip/pinch strength and range of motion showed results comparable to the contralateral hand. Opposition was excellent with an average Kapandji index of 9.6 in both groups. Elektra achieved slightly better functional scores in the DASH and MHQ score. Satisfaction was high in both groups, and 96% of the patients would recommend the procedure. Metacarpophalangeal hyperextension > 15° was seen in 3 patients per group preoperatively and was corrected to < 5° post-surgery. 3 Elektra prostheses were revised due to cup loosening and dislocation for cup and/or neck replacement or secondary trapeziectomy. 1 Moovis prosthesis was revised with an exchange of the neck to a larger size due to restricted movement. After the mean follow-up of 7.9 years in Elektra and 3.5 years in MOOVIS, cumulative survival was 68.6% vs. 95.2%, respectively. CONCLUSIONS: In this mid- to long-term retrospective analysis, total joint arthroplasty in primary trapeziometacarpal joint arthritis results in low pain levels, excellent mobility and clinical function. Patient satisfaction is overall high. While revision due to cup loosening occurred more often in patients with single-mobility implants, no cases of dislocation or loosening of components were observed in the dual-mobility group. TRIAL REGISTRATION: The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee of the Medical Faculty of Heidelberg University, reference number S-150/2020.

Postoperative complications and mobilisation following major abdominal surgery with vs. without fitness tracker-based feedback (EXPELLIARMUS): study protocol for a student-led multicentre randomised controlled trial (CHIR-Net SIGMA study group).

BACKGROUND: Postoperative complications following major abdominal surgery are frequent despite progress in surgical technique and perioperative care. Early and enhanced postoperative mobilisation has been advocated to reduce postoperative complications, but it is still unknown whether it can independently improve outcomes after major surgery. Fitness trackers (FTs) are a promising tool to improve postoperative mobilisation, but their effect on postoperative complications and recovery has not been investigated in clinical trials. METHODS: This is a multicentre randomised controlled trial with two parallel study groups evaluating the efficacy of an enhanced and early mobilisation protocol in combination with FT-based feedback in patients undergoing elective major abdominal surgery. Participants are randomly assigned (1:1) to either the experimental group, which receives daily step goals and a FT giving feedback about daily steps, or the control group, which is mobilised according to hospital standards. The control group also receives a FT, however with a blackened screen; thus no FT-based feedback is possible. Randomisation will be stratified by type of surgery (laparoscopic vs. open). The primary endpoint of the study is postoperative morbidity within 30 days measured via the Comprehensive Complication Index. Secondary endpoints include number of steps as well as a set of functional, morbidity and safety parameters. A total of 348 patients will be recruited in 15 German centres. The study will be conducted and organised by the student-led German Clinical Trial Network SIGMA. DISCUSSION: Our study aims at investigating whether the implementation of a simple mobilisation protocol in combination with FT-based feedback can reduce postoperative morbidity in patients undergoing major abdominal surgery. If so, FTs would offer a cost-effective intervention to enhance postoperative mobilisation and improve patient outcomes. TRIAL REGISTRATION: Deutsches Register Klinischer Studien (DRKS, German Clinical Trials Register): DRKS00016755, UTN U1111-1228-3320. Registered on 06.03.2019.

[Design and Evaluation of a Clinical Investigator Training for Student-lead Prospective Multicentre Clinical Trials: a CHIR-Net SIGMA Research-based Learning Project]. / Design und Evaluation eines Prüf-Studierenden-Kurses für studentische prospektive Multicenterstudien ­ ein CHIR-Net-SIGMA-Projekt zum forschenden Lernen.

BACKGROUND: Scientific skills are not sufficiently taught during medical training, neither in medical school nor during postgraduate education. This results in a lack of clinician scientists. In order to counter this problem, the surgical study network (CHIR-Net) founded SIGMA (Student-initiated German Medical Audit). This paper describes the development, performance and evaluation of a Clinical Investigator Training (CIT) aiming to qualify students to autonomously conduct clinical trials. MATERIAL AND METHODS: Based on the Kern cycle, a curriculum was developed, composed of three parts: online tutorials, a workshop and a follow-up period. The educational objectives were defined according to Bloom's taxonomy of knowledge. The learning objectives were based on the requirements of the "Network of Coordinating Centers for Clinical Trials" and the German Medical Association as well as content relevant to clinical studies. A wide range of educational instruments and assessments were used. By including all relevant professional groups involved in clinical trials, an interconnected working environment for students was generated. The increase in knowledge was assessed by a multiple-choice pre/post exam. The satisfaction of participants was analysed by a 5-point Likert scale, on which 5 indicated full approval. RESULTS: The first SIGMA CIT was realised in 2018; the workshop took place in Heidelberg in February. Thirty-two medical students from thirteen different centres participated. On average, 53.8 ± 8.3% of questions were answered correctly in the pre-test, compared with 71.2 ± 7.2% in the post-test (p < 0.0001). The maximal individual improvement was 30%; the lowest difference compared to the pre-test was 5%. Subjective evaluation results were positive with an average result of 4.63 ± 0.34 on a 5-point Likert scale. CONCLUSION: It is feasible to teach medical students the fundamentals of clinical trials. A compact Clinical Investigator Training using modern principles of teaching is able to prepare students for an autonomous performance of clinical trials.

Prospective multicentre cohort study of patient-reported outcomes and complications following major abdominal neoplastic surgery (PATRONUS) - study protocol for a CHIR-Net student-initiated German medical audit study (CHIR-Net SIGMA study).

BACKGROUND: One of the most important aspects of designing a clinical trial is selecting appropriate outcomes. Patient-reported outcomes (PROs) can provide a personal assessment of the burden and impact of a malignant disease and its treatment. PROs comprise a wide range of outcomes including basic clinical symptom scores and complex metrics such as health-related quality of life (HRQoL). There is limited data on how postoperative complications following cancer surgery affect symptoms and HRQoL. For this reason the primary aim of the PATRONUS study is to investigate how perioperative complications affect cancer-related symptoms and HRQoL in patients undergoing abdominal cancer surgery. The PATRONUS study is designed and will be initiated and conducted by medical students under the direct supervision of clinician scientists based on the concept of inquiry-based learning. METHODS: PATRONUS is a non-interventional prospective multicentre cohort study. Patients undergoing elective oncological abdominal surgery will be recruited at regional centres of the clinical network of the German Surgical Society (CHIR-Net) and associated hospitals. A core set of 12 cancer associated symptoms will be assessed via the PRO version of the Common Terminology Criteria for Adverse Events. The cancer-specific HRQoL will be measured via the computerised adaptive testing version of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30. PROs will be measured eight times over a period of six months. The short-term clinical outcome measure is the rate of postoperative complications (grade II to V) within 30 days according to the Clavien-Dindo classification. The long-term clinical outcome is overall survival within six months postoperative. DISCUSSION: PATRONUS will provide essential insights into the patients' assessment of their well-being and quality of life in direct relation to clinical outcome parameters following abdominal cancer surgery. Furthermore, PATRONUS will investigate the feasibility of multicentre student-led clinical research. TRIAL REGISTRATION: German Clinical Trials Register: DRKS00013035 (registered on October 26, 2017). Universal Trial Number (UTN): U1111-1202-8863.

Encouraging student-driven clinical research in Germany: the CHIR-Net SIGMA network.

Evidence should define and guide modern clinical care, yet many relevant questions in surgical practice remain unconfirmed by substantial data. Evidence-based medicine requires both the implementation of its principles in day-to-day work and the acquisition of new evidence preferably by randomized controlled trials and systematic reviews. Meaningful clinical research, however, is challenging to conduct, and its overall infrastructure in Germany was, until recently, considered poor compared to other leading countries. Although this has been significantly improved after the establishment of the Study Center of the German Surgical Society (SDGC) and the surgical clinical trial network CHIR-Net, limited focus has been put on the training, teaching, and recruitment of medical students to become competent clinical researchers and clinician scientists. To ensure continuing comprehensive clinical research in surgery, CHIR-Net aims to establish a student-driven multicenter research network in Germany, which is embedded in both the national CHIR-Net and the pan-European and international frameworks. Student-Initiated German Medical Audits (SIGMA) is a product of the strong collaboration between clinical scientists and medical trainees, enabling students to contribute to high-quality clinical trials. Additionally, participants are offered extensive training to support the next generation of research-active clinicians. Starting on 2018, SIGMA will perform its first multicenter observational study in Germany.

Dimensional matching of polycyclic aromatics with rectangular metallacycles: insertion modes determined by [C-H···π] interactions.

A family of Pd(II)/Pt(II) dinuclear receptors, designed to give a smooth increase in their cavity lengths (from 7.46-13.78 Å), is presented. Their inclusion complexes with a representative set of polycyclic aromatic substrates (naphthalene, carbazol, pyrene, and benzo[a]pyrene), were characterized and studied in aqueous solution and the solid state. By taking into account the dimensions of both receptors and substrates, an excellent complementarity was found between the size of the receptors and their ability to complex a given substrate. Furthermore, this dimensional matching results in specific binding modes depending on the ability of the guest to establish stabilizing [C-H···π] interactions with the host.

Complexation and extraction of PAHs to the aqueous phase with a dinuclear Pt(II) diazapyrenium-based metallacycle.

New palladium and platinum metallacycles have been synthesized by reaction between a 2,7-diazapyrenium-based ligand and Pd(II) and Pt(II) complexes. The inclusion complexes between the metallacycles and polycyclic aromatic hydrocarbons (PAHs) in CD(3)NO(2) and D(2)O were studied by NMR spectroscopy. The structures of the inclusion complexes of the Pt metallacycle as host with pyrene, phenanthrene, and triphenylene were confirmed by single crystal X-ray crystallography. The association constants between the Pt metallacycle and the selected PAHs were determined in CH(3)CN following the characteristic charge-transfer band displayed in their UV/Vis absorption spectrum. Although in aqueous solution all the complexes showed a 1:1 stoichiometry, in CH(3)CN the Job plot indicated a 2:1 stoichiometry for complexes with triphenylene and benzo[a]pyrene. The estimated association constants in water correlate with the hydrophobicity of the PAH, indicating that hydrophobic forces play an important role in the complexation process.

Complexation of pyrene in aqueous solution with a self-assembled palladium metallocycle.

A bidentate ligand based on N-monoaryl 4,4'-bipyridinium undergoes self-assembly to dinuclear rectangular metallocycles upon coordination to palladium(II) and platinum(II) centers. These metallocycles form a very stable complex with pyrene in aqueous solution and in the solid state. A crystal structure of the pyrene inclusion complex is presented. The association constants between pyrene and metallocycle 3a in organic solvents and water (K(a) = 2.3 x 10(6)) were determined.

Regioselective catenation of dinuclear palladium and platinum metallocycles promoted by pi...pi interactions.

Dinuclear metallocycles were assembled from an L-shaped bidentate ligand based on 4,4'-bipyridine and palladium or platinum square-planar cis complexes. The palladium (4a,b) or platinum (5a,b) square metallocycles were obtained as 1:1 regioisomeric mixtures depending on which pair of coordinative nitrogen atoms binds to the metal center. The squares display a pi-deficient cavity suitable to incorporate two pi-donor aromatic systems. Therefore, the reaction with macrocyclic polyethers (BPP34C10 or DN38C10) resulted in the regioselective self-assembly of the [3]catenanes 4a(BPP34C10 or DN38C10)(2) x 6 PF(6) and 5a(BPP34C10 or DN38C10)(2) x 6 PF(6) because only macrocycles 4a and 5a present the correct disposition of the pi-deficient aromatic systems to maximize the pi...pi stacking interactions. Single-crystal X-ray analyses of [3]catenanes revealed that the structures are additionally stabilized by [C-H...O], [N-H...O] bonds and [C-H...pi] interactions. The 1:2 inclusion complexes of metallocycles were prepared by self-assembly of three components: the ligand 1-(4-(pyridin-4-yl)benzyl)-4,4'-bipyridin-1-ium, a square planar complex M(en)(NO(3))(2) (M = Pd or Pt, en = ethylenediamine), and a dioxoaromatic guest in a 2:2:2 ratio. The comparative study of the formation of 1:2 inclusion complexes has allowed us to conclude that the pi...pi interactions between the host and guests are responsible for the observed regioselectivity.

Stereoselective self-assembly of atropoisomeric Pd(II) metallocycles induced by an aromatic guest.

A new dinuclear Pd(II) metallocycle consisting of a 4,4'-bipyridin-1-ium ligand with a quinoline moiety was self-assembled in aqueous solution with the aid of template molecules; the situation found in solution in which both syn and anti or only the anti atropoisomers are observed strongly relies on the intermolecular host-guest interactions.

Self-assembly of 1:2 inclusion complexes between a metallocycle host and dihydroxyaromatic guests: a redox controlled complexation process.

Two new 1:2 inclusion complexes were prepared by self-assembly of three components: a ligand based on 4,4'-bipyridinium, a square-planar Pd complex, and a dihydroxyaromatic guest (hydroquinone or 1,5-dihydroxynaphthalene) in a 2:2:2 ratio. Their X-ray structural analyses revealed that the complexes are stabilized by pi-pi stacking and [C-H...pi] interactions.

Synthesis of new self-assembled PdII and PtII rectangular metallomacrocycles: a comparative study of their inclusion complexes.

New palladium and platinum metallocycles have been synthesized by reacting 4,4'-bipyridinium-based ligands with PdII and PtII complexes. Strict thermodynamic self-assembly of 1 and [M(en)(NO3)2] (M=Pd, Pt) 6 a,b afforded metallocycles 7 a,b. However, the synthesis of 8 a,b and 9 a,b required a self-assembly process that used sodium p-phenylenediacetate (12) as a template. Finally, metallocycles 10 a,b were synthesized under high dilution conditions from ligand 4. The formation of inclusion complexes between metallocycles 7-10 and substrates 13 and 14 were studied by low-temperature 1H NMR, and the association constants were determined in nitromethane and water by following the characteristic charge-transfer band that these metallomacrocycles show in their UV-visible absorption spectra. A clear correlation between the affinity for a substrate and the dimensions of the metallocycle was observed. Metallocycles 8 b and 9 b exhibited the highest binding constants in water and nitromethane. This observation is in agreement with the DFT (B3LYP)-optimized geometries obtained for the different metallomacrocycles, which indicate that only macrocycles 8 and 9 possess a cavity with a width larger than 3.5 A. The insertion of hydroquinone or diol 13 into the cavity of metallocycle 11 a was confirmed by single-crystal X-ray crystallography.

[Trends in vigorous physical activity versus physical inactivity among 11-15 year olds from 1988 to 2002]. / Udviklingen i energisk fysisk aktivitet og fysisk inaktivitet blandt 11-15-årige 1988-2002.

INTRODUCTION: The increasing prevalence of overweight and obesity among children and adolescents suggests a need to study the development in main predictors of obesity, like eating habits and physical activity. The objective was to describe self-reported vigorous physical activity versus physical inactivity among children and adolescents over a period of 14 years, 1988-2002. MATERIAL AND METHODS: The study population was the Health Behaviour in School-aged Children (HBSC) study among nationally representative samples of 11, 13 and 15 year old students in 1988, 1991, 1994, 1998, and 2002. The data collection used the standardised HBSC questionnaire which included items about vigorous physical activity (VPA) outside school hours per week. We defined physically inactivity as 0 hours of VPA per week and high activity as at least 7 hours of VPA per week. RESULTS: The prevalence of high activity was higher among boys than girls and increased by age. The prevalence of physically inactive students increased from 1988 to 2002, especially among the 15 year olds. The proportion of students with high activity decreased from 1988 to 2002, especially among the 15 year olds. CONCLUSION: A large proportion of children and adolescents do not comply with the national recommendations that children should be physically active at least 60 minutes per day. The physical activity level decreased from 1988 to 2002. There is a need for extraordinary efforts to increase physical activity among children and adolescents.

New hybrid [2]catenanes based on a 4,4'-bipyridinium ligand.

The self-assembly-mediated synthesis of metallomacrocycles 4a and 4b from (en)M(NO3)2 (M = Pd, Pt) and bipyridinium ligand 3 is described. The reaction is templated by disodium p-phenyldiacetic dicarboxylate, which is inserted into the macrocyclic cavity. Similarly, the self-assembly process between ligand 3, (en)M(NO3)2 (M = Pd, Pt), and the macrocyclic polyether 6 resulted in the formation of hybrid catenanes 7a and 7b. In the [2]catenanes, the circumrotation of the macrocyclic polyether through the cavity of the metallocycle is slow on the 1H NMR time scale.