Assoziationen zwischen exekutivem Funktionieren und dem Volumen der kortikalen grauen Substanz bei Älteren

Introduction: Preserved executive functioning (EF) promotes superior daily functioning in the elderly and protects against dementia development. In this study, we sought to clarify the role of atrophy-corrected cortical grey matter (GM) volume as a potential brain reserve (BR) marker for EF in the elderly. Methods: In total, 206 pre-surgical subjects without any evidence for neuropsychiatric disorders (72.50 ± 4.95 years; mean MMSE score 28.50) from the BioCog cohort study (www.biocog.eu) were investigated. EF was assessed with Trail Making Test B (TMT B). Global/lobar GM volumes were acquired with T1 MP-RAGE using a 3.0 Tesla Siemens scanner with a 32-channel headcoil. The brain imaging software package FreeSurfer was used to quantify GM volumes of the frontal, temporal, occipital and parietal brain lobes. Adjusting for key covariates including a brain atrophy index, multiple regression analysis was used to study associations of MRI markers and TMT B. Results: All lobar/global GM volumes significantly predicted the TMT B score independently of brain atrophy (ß = −0.201 to −0.275, p = 0.001–0.012). Atrophy-corrected global GM volume was the most accurate predictor (ß = −0.275, p=0.001). Conclusion: Our results indicate that atrophy-corrected GM volume as an archaeological estimate of maximal GM size in youth may serve as a future BR predictor for cognitive decline in the elderly.Einleitung: Um im Alter einen normalen Tagesablauf gewährleisten zu können, ist vor allem der Erhalt exekutiver Funktionen (EF) grundlegend; diese scheinen zudem dementielle Entwicklungen vorhersagen zu können. Wir untersuchten die Assoziation zwischen atrophie-korrigierter grauer Substanz (GS), als Reserve für Gehirnkapazität, und dem Aufrechterhalten von EF im Alter. Material und Methoden: Insgesamt wurden 206 präoperative Probanden ohne Anhalt für das Vorliegen neuropsychiatrischer Erkrankungen (72.50 ± 4.95 Jahre; durchschnittlicher MMSE Wert 28.50) im Rahmen der BioCog Kohortstudie (www.biocog.eu) untersucht. EF wurde primär beurteilt durch die Anwendung des Trail Making Test B (TMT B). Ein 3.0 Tesla Siemens Scanner mit einer 32-Kanal Kopfspule wurde zur Akquisition von T1 MP-RAGE Daten genutzt. Zur Bestimmung des globalen Volumens sowie der Volumina der GS der einzelnen Hirnlappen wurde die Software FreeSurfer angewendet. Mittels multipler linearer Regressionsanalysen, mit Korrektur für entscheidende Kovariaten, einschließlich eines Index für Hirnatrophie (Anteil von Hirnparenchym am intrakraniellen Volumen), wurden Volumina der GS mit dem TMT B assoziiert. Ergebnisse: Alle Volumina der GS, insbesondere das Volumen der globalen GS, waren, unabhängig von der vorliegenden Hirnatrophie, signifikant mit dem TMT B assoziiert (ß = −0.201 bis −0.275, p = 0.001–0.012). Schlussfolgerung: In künftigen Studien zur morphologischen Reservekapazität bei Älteren könnte das atrophie-korrigierte Volumen der GS, als eine Schätzung des maximalen Umfangs der GS in der Jugend, herangezogen werden und als Prädiktor für den Rückgang des kognitiven Vermögens dienen

In vivo characterization of 3D-printed polycaprolactone-hydroxyapatite scaffolds with Voronoi design to advance the concept of scaffold-guided bone regeneration

Three-dimensional (3D)-printed medical-grade polycaprolactone (mPCL) composite scaffolds have been the first to enable the concept of scaffold-guided bone regeneration (SGBR) from bench to bedside. However, advances in 3D printing technologies now promise next-generation scaffolds such as those with Voronoi tessellation. We hypothesized that the combination of a Voronoi design, applied for the first time to 3D-printed mPCL and ceramic fillers (here hydroxyapatite, HA), would allow slow degradation and high osteogenicity needed to regenerate bone tissue and enhance regenerative properties when mixed with xenograft material. We tested this hypothesis in vitro and in vivo using 3D-printed composite mPCL-HA scaffolds (wt 96%:4%) with the Voronoi design using an ISO 13485 certified additive manufacturing platform. The resulting scaffold porosity was 73% and minimal in vitro degradation (mass loss <1%) was observed over the period of 6 months. After loading the scaffolds with different types of fresh sheep xenograft and ectopic implantation in rats for 8 weeks, highly vascularized tissue without extensive fibrous encapsulation was found in all mPCL-HA Voronoi scaffolds and endochondral bone formation was observed, with no adverse host-tissue reactions. This study supports the use of mPCL-HA Voronoi scaffolds for further testing in future large preclinical animal studies prior to clinical trials to ultimately successfully advance the SGBR concept

Public debt and growth: heterogeneity and non-linearity

We study the long-run relationship between public debt and growth in a large panel of countries. Our analysis builds on theoretical arguments and data considerations in modelling the debt-growth relationship as heterogeneous across countries. We investigate the debt-growth nexus adopting linear and non-linear specifications, employing novel methods and diagnostics from the time-series literature adapted for use in the panel. We find some support for a negative relationship between public debt and long-run growth across countries, but no evidence for a similar, let alone common, debt threshold within countries

Preclinical assessment of a novel aspirator device for intramedullary bone graft harvesting

To repair large bone defects, the patient's own bone material is collected using the Reamer-Irrigator-Aspirator (RIA) system. The RIA system offers a way to extract bone from the inner part of long bones, such as the thigh. However, the RIA system has limitations as it is not very intuitive for surgeons to use and the quality of the bone graft is controversial in the literature. In in vitro and in vivo studies, we have investigated a novel device that aims to simplify and improve the intramedullary bone harvesting process in order to achieve improved outcomes for patients with bone defects

In-Hospital Clinical Outcomes in Patients with Fragility Fractures of the Lumbar Spine, Thoracic Spine, and Pelvic Ring: A Comparison of Data before and after Certification as a DGU® Geriatric Trauma Centre

Background and Objectives: The implementation of orthogeriatric co-management (OGCM) reflects the demand for interdisciplinary collaborations due to the increasing comorbidities of geriatric trauma patients. This study aimed to assess clinical in-hospital outcomes in lumbar spine, thoracic spine, and pelvic ring fragility fracture patients before and after the implementation of a Geriatric Trauma Centre (GTC) certified by the German Trauma Society (DGU®). Materials and Methods: In this observational, retrospective cohort study, geriatric trauma patients (>70 years of age) were stratified into either a pre-GTC group (hospital admission between 1 January 2012 and 31 December 2013) or a post-GTC group (hospital admission between 1 January 2017 and 31 December 2018). Patients’ pre-injury medical complexity was measured by ASA class (American Society of Anaesthesiologists classification), the use of anticoagulant medication, and the ACCI (Age-adjusted Charlson Comorbidity Index). Outcome parameters were patients’ in-hospital length of stay (LOS) and mortality rates, as well as new in-hospital findings and diagnoses. Further, the necessity of deviation from initial management plans due to complications was assessed using the Adapted Clavien–Dindo Scoring System in Trauma (ACDiT score of ≥1). Results: Patients in the post-GTC group (n = 111) were older (median age 82.0 years) compared to the pre-GTC group (n = 108, median age 80.0 years, p = 0.016). No differences were found in sex, body mass index, ASA class, or ACCI (all p > 0.05). Patients in the post-GTC group used vitamin K antagonists or direct oral anticoagulants more frequently (21.3% versus 10.8%). The incidence of non-surgical treatment and mortality was comparable between groups, while LOS tended to be shorter in the post-GTC group (7.0 days versus 9.0 days, p = 0.076). In the post-GTC group, the detection of urinary tract infections (UTI) increased (35.2% versus 16.2%, p = 0.001), and the delirium diagnoses tended to increase (13.0% versus 6.3%, p = 0.094), while an ACDiT score of ≥1 was comparable between groups (p = 0.169). Conclusions: In this study including lumbar spine, thoracic spine, and pelvic ring geriatric fragility fractures, patients in the post-GTC group were more medically complex. More UTIs and the tendency for increased delirium detection was observed in the post-GTC group, likely due to improved diagnostic testing. Nonetheless, the necessity of deviation from initial management plans (ACDiT score of ≥1) was comparable between groups, potentially a positive result of OGCM

Biodegradable interbody cages for lumbar spine fusion : Current concepts and future directions

Lumbar fusion often remains the last treatment option for various acute and chronic spinal conditions, including infectious and degenerative diseases. Placement of a cage in the intervertebral space has become a routine clinical treatment for spinal fusion surgery to provide sufficient biomechanical stability, which is required to achieve bony ingrowth of the implant. Routinely used cages for clinical application are made of titanium (Ti) or polyetheretherketone (PEEK). Ti has been used since the 1980s; however, its shortcomings, such as impaired radiographical opacity and higher elastic modulus compared to bone, have led to the development of PEEK cages, which are associated with reduced stress shielding as well as no radiographical artefacts. Since PEEK is bioinert, its osteointegration capacity is limited, which in turn enhances fibrotic tissue formation and peri-implant infections. To address shortcomings of both of these biomaterials, interdisciplinary teams have developed biodegradable cages. Rooted in promising preclinical large animal studies, a hollow cylindrical cage (Hydrosorb™) made of 70:30 poly-l-lactide-co-d, l-lactide acid (PLDLLA) was clinically studied. However, reduced bony integration and unfavourable long-term clinical outcomes prohibited its routine clinical application. More recently, scaffold-guided bone regeneration (SGBR) with application of highly porous biodegradable constructs is emerging. Advancements in additive manufacturing technology now allow the cage designs that match requirements, such as stiffness of surrounding tissues, while providing long-term biomechanical stability. A favourable clinical outcome has been observed in the treatment of various bone defects, particularly for 3D-printed composite scaffolds made of medical-grade polycaprolactone (mPCL) in combination with a ceramic filler material. Therefore, advanced cage design made of mPCL and ceramic may also carry initial high spinal forces up to the time of bony fusion and subsequently resorb without clinical side effects. Furthermore, surface modification of implants is an effective approach to simultaneously reduce microbial infection and improve tissue integration. We present a design concept for a scaffold surface which result in osteoconductive and antimicrobial properties that have the potential to achieve higher rates of fusion and less clinical complications. In this review, we explore the preclinical and clinical studies which used bioresorbable cages. Furthermore, we critically discuss the need for a cutting-edge research program that includes comprehensive preclinical in vitro and in vivo studies to enable successful translation from bench to bedside. We develop such a conceptual framework by examining the state-of-the-art literature and posing the questions that will guide this field in the coming years.</p

Sturzprävention bei älteren Menschen durch ergotherapeutische Wohnraumanalyse, -beratung und -anpassung: eine Prozessdarstellung [Fall prevention in old people through occupational therapy home assessment, consultation and modification: a process outline]

Falls occur frequently in old people and are associated with relevant short-term and long-term trauma sequelae. Particularly in the light of demographic change, preventive measures such as falls prevention are increasingly gaining in importance. Occupational therapy home assessments enable the evaluation of external and behavioral risk factors for falls in the context of environmental prevention. Environmental prevention is an effective measure in preventing morbidity and mortality related to falls in old people and the increase in healthcare costs associated with falls. Occupational therapy home assessments effectively reduce fall risk and fall rate among older people at risk of falling and can be implemented in the context of existing regulatory frameworks. The aim of this overview is to illustrate the optimal process of home assessment and adaptation for patients at risk of falling by general practitioners, orthopedic surgeons and occupational therapists.</p

Anterior knee pain after total knee arthroplasty: A multifactorial analysis

Purpose: Dissatisfaction and an impaired quality of life after total knee arthroplasty (TKA) is often associated with postsurgical anterior knee pain (AKP). The underlying pathological mechanisms are not yet fully understood. Therefore, a multifactorial approach encompassing clinical and radiological parameters seemed reasonable and promising to investigate postsurgical AKP. Methods: In this cross-sectional study, 25 patients without and 25 patients with postsurgical AKP after unilateral TKA were randomly recruited from a larger cohort of patients. Multiple clinical and radiological parameters—including real-time shear wave elastography (SWE) to measure the patellar and quadriceps tendon elasticity—were acquired and subsequently associated with AKP. For statistical analysis, SPSS (IBM, version 25) was used. Results: In total 50 participants (58.0% men, mean age 63.42 years, mean body mass index 29.75 kg/m2), having different prosthetic designs implanted, were included. Independently of key covariates, the strength of the quadriceps muscle (p = 0.021), a thinner inlay (p = 0.041), and a lower position of the patella (p = 0.041) were associated with AKP. Although no correlation with AKP was found (p = 0.346, resp. p = 0.154), we observed significantly decreased Young’s modulus of the patellar and quadriceps tendons for the involved knee compared to the uninvolved knee (p < 0.001). Conclusion: In conclusion, quadriceps muscle strength, inlay thickness, and the patella position might be of particular relevance in avoiding postsurgical AKP. Future studies with larger sample sizes are needed to clarify the impact of quadriceps muscle strength and the postoperative patella position as well as the role of SWE as a personalized modifiable prediction marker.</p