The aim of this study is to analyse the effect of an additional radial buttress plate for palmar plate osteosynthesis in an AO/OTA 2R3 C2.1 fracture model. Nine pairs of freshly frozen radii were analysed for pathology and bone mineral density and divided into two matched groups. One group was treated with a variable-angle palmar locking plate alone, while the second group received an additional radial buttress plate for radiopalmar double plating. An AO/OTA 2R3 C2.1 fracture was created in all specimens. The biomechanical tests were performed according to previously published protocols. Stiffness, axial displacement of the construct, as well as fragment-specific movements and rotations were assessed. No implant failure was observed. In the total cohort, stiffness increased (p < 0.01) and axial construct displacement decreased (p < 0.05). The mobility of the ulnar fragment to the shaft during cyclic testing was lower with double plating, both at baseline and endpoint (all p < 0.01). Fragment movements increased over the course of testing and were significant for the radial articular fragment relative to the shaft in the total cohort (p < 0.01). Baseline rotation of the ulnar fragment and endpoint rotation of the radial fragment in relation to the shaft were lower with double plating (all p < 0.05). In both constructs, the rotation of the ulnar fragment relative to the shaft was lower than that of the radial fragment at both timepoints (all p < 0.05). Biomechanically, the addition of a radial buttress plate to a standard palmar locking plate did not alter global construct stiffness, but demonstrated advantages in fragment-specific stability in comminuted distal radius fractures.
Importance:With blood-based phosphorylated tau biomarkers soon to be used for diagnosis of Alzheimer disease, analyzing tau levels in other conditions could enhance biomarker interpretability. Moreover, mechanisms of tau release into circulation remain unclear. Objective:To evaluate concentrations of phosphorylated and nonphosphorylated tau variants in the blood of patients with multiple traumatic injuries on days 0, 1, 5, and 10 and investigate biological processes driving tau release. Design, Setting, and Participants:This multiple-trauma cohort (injury severity score, ≥18) included 45 severely injured patients with (n = 27) and without (n = 18) moderate-to-severe traumatic brain injury on emergency computed tomographic imaging. Controls consisted of 24 healthy volunteers. Participants were recruited from December 1, 2013, to October 31, 2022. Blood samples were analyzed for brain-derived tau (BD-tau), total tau (t-tau), and phosphorylated tau 217 (p-tau217) and 231 (p-tau231) levels. Associations among tau concentrations, clinical data, and outcome (eg, Glasgow Coma Scale [GCS] score) were assessed. Data were analyzed from March 1, 2023, to September 30, 2024. Exposures:Serum BD-tau, t-tau, p-tau217, and p-tau231 levels. Results:A total of 214 serum samples were analyzed. Median age of the 45 patients was 48 (IQR, 33-60) years (35 [77.8%] male); median age of the 24 controls, 43 (IQR, 28-50) years (16 [66.7%] male). Median serum levels of tau variants were increased in patients with multiple traumatic injuries at day 0 compared with controls (t-tau: 43 [IQR, 21-95] vs 3 [IQR, 3-5] pg/mL; BD-tau: 78 [IQR, 30-343] vs 2 [IQR, 2-3] pg/mL; p-tau231: 61 [IQR, 21-79] vs 2 [IQR, 1-3] pg/mL; all, P < .001). Only median BD-tau levels remained elevated until day 10 (day 1, 25 [IQR, 14-69] pg/mL; day 5, 9 [IQR, 4-15] pg/mL; day 10, 8 [IQR, 4-18] pg/mL). Median tau levels at admission were higher in patients with lower GCS scores (BD-tau: 107 [ IQR, 59-838] vs 33 [IQR, 24-78] pg/mL [P = .01]; p-tau231: 76 [IQR, 36-114] vs 28 [IQR, 9-63] pg/mL [P = .02]). Elevated median tau levels were also observed in patients with hemorrhagic shock vs those without shock (eg, BD-tau on day 0: 113 [IQR, 78-378] vs 31 [IQR, 24-61] pg/mL; P = .002) and in nonsurvivors vs survivors with uncomplicated courses (eg, BD-tau on day 1: 92 [IQR, 22-527] vs 16 [IQR, 7-23] pg/mL; P = .009). Conclusions and Relevance:In this exploratory study among a cohort of patients with multiple traumatic injuries, levels of tau variants reflected both direct and indirect neurological injury, with BD-tau showing the most persistent elevation in the acute phase.
BackgroundIn Germany, first-trimester abortions are legally restricted but allowed under certain conditions, including mandatory counseling and a reflection period. Accessibility concerns persist. To address gaps in medical training, we developed an interdisciplinary learning module on first-trimester abortion care.MethodsWe piloted the module in two sessions giving access to all medical students as an extracurricular learning opportunity. We conducted non-paired surveys across the medical school prior to the module and with our participants after the module to identify changes in attitudes as well as in intentions to treat.ResultsWe received a total of 297 responses. Most of the students (94%) were in favor of legalizing abortion laws. However, only 30% self-assessed their knowledge as sufficient, 40% of the students showed the willingness to perform abortions within the consultation clause and 43% of the students agreed to consult patients on abortion provision but not perform them themselves. The right for practitioners to object the performance of abortions was highly agreed upon (78%). After our pilot sessions, we received 53 evaluation surveys from 118 participants. Students reported a significant increase in knowledge. We observed a significant increase in general support and intention to treat after our module.ConclusionsTeaching about abortion is essential for our future healthcare providers. Overall, we see a great response to our new learning module and can hope for practice-changing effects on the provision of abortion care in the future. We integrated the module into our regular teaching catalogue.
Aquaporin 4 (AQP4), a water channel expressed in astrocytic end feet forming the blood brain barrier, is predominantly expressed in the central nervous system. Cerebrospinal fluid (CSF) AQP4 has now been suggested as a possible fluid biomarker in Alzheimer's disease. However, its diagnostic potential in primary neuroinflammatory diseases, where also AQP4 autoantibodies can circulate, has so far not been studied. We investigated the CSF of 301 patients for AQP4 and GFAP using ELISA. The single-center cohort consisted of patients with multiple sclerosis (n = 81), chronic inflammatory demyelinating polyneuropathy (n = 23), Guillain-Barré-Syndrome (n = 13), meningitis/ encephalitis (Men/Enc) (n = 19), myelin oligodendrocyte glycoprotein antibody disease (n = 6), neuromyelitis optica spectrum disease (NMOSD) (n = 12), and non-immune mediated polyneuropathy (NIP) patients (n = 49). 98 patients without acute or chronic neuroinflammation and neurodegneration served as controls. Both CSF AQP4 (r = 0.45 (95%CI: 0.36-0.54), p < 0.0001) and GFAP (r = 0.4 (95%CI: 0.30-0.49), p < 0.0001) correlated with age in the whole cohort. CSF AQP4 levels were elevated in the NIP group compared to control, MS and Men/Enc patients (p = 0.002, p = 0.029 and 0.005, respectively). When stratified further, the hereditary NIP patients (n = 26) displayed the highest AQP4 levels of all groups. CSF GFAP was elevated in the AQP4 autoantibody positive NMOSD group but was not increased in AQP4 autoantibody negative NMOSD patients. CSF AQP4 levels were similar in both NMOSD groups. Combining AQP4 and GFAP levels or calculating their ratio did not prominently enhance diagnostic discrimination. The study highlights the diagnostic potential of AQP4 as a fluid biomarker in neurological conditions, especially in peripheral neuropathies, while confirming GFAP as marker for astrocytic injury in autoantibody positive NMOSD patients. Our findings suggest that AQP4 and GFAP reflect different astrocytic processes in neurological diseases.
This biomechanical study compared the fracture stability of a palmar plate combined with a headless compression screw (HCS) with that of a radiopalmar double-plate construct for AO/OTA 23-C2.1 distal radius fractures with metaphyseal defect zones. Eleven matched pairs of cryopreserved human radii were prepared with standardized AO/OTA 23-C2.1 fractures. Left radii (n = 11) were fixed with a palmar plate plus HCS, while right radii (n = 11) received a radiopalmar double-plate construct. Construct stiffness and axial displacement were assessed using a universal testing machine. Interfragmentary range of motion (ROM) and rotation (ROT) were quantified using an optical three-dimensional motion-tracking system. Measurements were obtained before and after 5000 cycles of dynamic axial loading at 150 N. Two specimen pairs were excluded due to early failure or incomplete data acquisition. Both constructs demonstrated comparable stiffness and axial displacement, with no implant loosening or hardware failure observed. Interfragmentary ROM did not differ significantly between groups. However, the plate–HCS construct showed greater variability in rotational parameters. Initial radial-shaft rotation was significantly greater in the plate–HCS group (1.14° vs. 0.51°, p = 0.02). After cyclic loading, ulnar-shaft rotation increased significantly in the plate–HCS group (0.97° to 1.16°, p = 0.02) but not in the double-plate group. In this cadaveric model, fixation with a palmar plate combined with an HCS provided comparable axial stability but demonstrated greater variability and less consistent rotational control compared with radiopalmar double plating. Clinical studies are required to determine whether this less invasive construct achieves equivalent outcomes in vivo.
