Characteristics of two different locking compression plates in the volar fixation of complex articular distal radius fractures

Objectives: To investigate the differences of open reduction and internal fixation (ORIF) of complex AO Type C distal radius fractures between two different models of a single implant type. Methods: A total of 136 patients who received either a 2.4 mm (n = 61) or 3.5 mm (n = 75) distal radius locking compression plate (LCP DR) using a volar approach were followed over two years. The main outcome measurements included motion, grip strength, pain, and the scores of Gartland and Werley, the Short-Form 36 (SF-36) and the Disabilities of the Arm, Shoulder, and Hand (DASH). Differences between the treatment groups were evaluated using regression analysis and the likelihood ratio test with significance based on the Bonferroni corrected p-value of 0.052) and grip strength measurements relative to the contralateral healthy side (p = 0.583). In addition, DASH and SF-36 component scores as well as pain were not significantly different between the treatment groups throughout the two-year period (all p ≥ 0.005). No patient from either treatment group had a step-off > 2 mm. Conclusions: Differences in plate design do not influence the overall final outcome of fracture fixation using LCP

Validation of a statistical shape model-based 2D/3D reconstruction method for determination of cup orientation after THA

Purpose: The aim of this study was to validate the accuracy and reproducibility of a statistical shape model-based 2D/3D reconstruction method for determining cup orientation after total hip arthroplasty. With a statistical shape model, this method allows reconstructing a patient-specific 3D-model of the pelvis from a standard AP X-ray radiograph. Cup orientation (inclination and anteversion) is then calculated with respect to the anterior pelvic plane that is derived from the reconstructed model. Materials and methods: The validation study was conducted retrospectively on datasets of 29 patients (31 hips). Among them, there were 15 men (15 hips) and 14 women (16 hips). The average age of the patients was 69.4±8.5(49−82) years. Each dataset has one postoperative X-ray radiograph and one postoperative CT scan. The postoperative CT scan for each patient was used to establish the ground truth for the cup orientation. The cup anteversion and inclination that were calculated from the 2D/3D reconstruction method were compared to the associated ground truth. To validate reproducibility and reliability, two observers performed measurements for each dataset twice in order to measure the reproducibility and the reliability of the 2D/3D reconstruction method. Results: Our validation study demonstrated a mean accuracy of 0.4 ± 1.8°(−2.6° to 3.3°) for inclination and a mean accuracy of 0.6±1.5°(−2.0° to 3.9°) for anteversion. Through the Bland-Altman analysis, no systematic errors in accuracy were detected. The method showed very good consistency for both parameters. Conclusions: Our validation results demonstrate that the statistical shape model-based 2D/3D reconstruction-based method is an accurate, consistent, and reproducible technique to measure cup orientation from postoperative X-ray radiographs. The best results were achieved with radiographs including the bilateral anterior superior iliac spines and the cranial part of non-fractured pelvise

Method of two-stage implantation of a joint prosthesis and prosthetic product

A two step surgical technique for implantation of a joint prosthesis. A bone cavity adjacent the effected joint is prepared for receipt of a prosthetic stem having porosities therealong for dynamic bony interfacial fixation and a tip adapted for subsequent removable securement to a joint element. The effected joint is resectioned in a subsequent second surgical technique and the opposing joint component is prepared for receipt of a prosthetic joint. The prosthetic joint is then implanted and removably secured to said previously implanted stem. A two piece implantable prosthesis is also disclosed and claimed

Bio-inspired mineral growth on porous spherulitic textured poly(L-lactic acid)/bioactive glass composite scaffolds

It has been shown that texture can strongly influence the adhesion, orientation and proliferation of cells onto the surface of biomaterials. Additionally, it is possible to imprint micrometer level textures throughout the scaffolds by melt compounding PLLA/polyethylene oxide (PEO) blend, quenching followed by leaching of PEO in water. The objective of this work is to verify how the texture in 3D porous PLLA/Bioglass®composite scaffolds may influence the precipitation of apatite in vitro. © 2008 WILEY-VCH Verlag GmbH & Co. KGaA.Financial support for this work was provided by FCT, through tire POCTI and FEDER programmes, and projects POCTI/FIS/61621/2004 and PTDC/QUI/69263/2006. S. Ghosh thanks FCT for awarding the PhD grant, SFRH/BD/12657/2003. This work was also partially supported by the European Union funded STREP Project HIPPOCRATES(NMP3-CT-2003-505758)

Early discharge using single cardiac troponin and copeptin testing in patients with suspected acute coronary syndrome (ACS): a randomized, controlled clinical process study

Aims This randomized controlled trial (RCT) evaluated whether a process with single combined testing of copeptin and troponin at admission in patients with low-to-intermediate risk and suspected acute coronary syndrome (ACS) does not lead to a higher proportion of major adverse cardiac events (MACE) than the current standard process (non-inferiority design). Methods and results A total of 902 patients were randomly assigned to either standard care or the copeptin group where patients with negative troponin and copeptin values at admission were eligible for discharge after final clinical assessment. The proportion of MACE (death, survived sudden cardiac death, acute myocardial infarction (AMI), re-hospitalization for ACS, acute unplanned percutaneous coronary intervention, coronary artery bypass grafting, or documented life threatening arrhythmias) was assessed after 30 days. Intention to treat analysis showed a MACE proportion of 5.17% [95% confidence intervals (CI) 3.30-7.65%; 23/445] in the standard group and 5.19% (95% CI 3.32-7.69%; 23/443) in the copeptin group. In the per protocol analysis, the MACE proportion was 5.34% (95% CI 3.38-7.97%) in the standard group, and 3.01% (95% CI 1.51-5.33%) in the copeptin group. These results were also corroborated by sensitivity analyses. In the copeptin group, discharged copeptin negative patients had an event rate of 0.6% (2/362). Conclusion After clinical work-up and single combined testing of troponin and copeptin to rule-out AMI, early discharge of low- to intermediate risk patients with suspected ACS seems to be safe and has the potential to shorten length of stay in the ED. However, our results need to be confirmed in larger clinical trials or registries, before a clinical directive can be propagate

Isoelastic implants with improved anchorage means

Isoelastic implants are provided with a surface roughness for anchorage in and load transmission to the surrounding tissue. The surface roughness is formed of one or more of the structures including undulations, or grooves, or pores, or lacunae, or gaps and protrusions. The roughness is located at two separate and confined regions along the surfaces of the implant which are intended for transmitting loads from the surrounding tissue into the implant or vice versa. The regions for containing the roughness are confined to two small areas at the opposite ends of the implant\u27s surface. The ends are defined in relation to the direction of the load to be transmitted through the surfaces

Soft tissue implant with micron-scale surface texture to optimize anchorage

A soft tissue implant device such as a catheter, heart valve, or plastic or reconstructive surgical material, to be at least partially embedded in an implantation site in soft organic tissue of a living organism includes a body defining a surface layer extending over the portion of the body contacting the organic tissue. The surface layer defines a three-dimensional pattern with an exterior surface defining a plurality of spaces and a plurality of solid surface portions. The spaces have a mean bridging distance ranging from greater than 1.0 micron to less than 4.0 microns and the solid surface portions have mean breadths ranging from 0.10 micron to 2.0 microns. The mean bridging distance is preferably greater than 1.4 microns and less than 1.9 microns. The exterior surface is substantially free of indentations having a bridging distance measuring in a range from between 10.0 microns and 1,000 microns

Soft tissue implant with micron-scale surface texture to optimize anchorage

A soft tissue implant device such as a catheter, heart valve, or plastic or reconstructive surgical material, to be at least partially embedded in an implantation site in soft organic tissue of a living organism includes a body defining a surface layer extending over the portion of the body contacting the organic tissue. The surface layer defines a three-dimensional pattern with an exterior surface defining a plurality of spaces and a plurality of solid surface portions. The spaces have a mean bridging distance ranging from greater than 1.0 micron to less than 4.0 microns and the solid surface portions have mean breadths ranging from 0.10 micron to 2.0 microns. The mean bridging distance is preferably greater than 1.4 microns and less than 1.9 microns. The exterior surface is substantially free of indentations having a bridging distance measuring in a range from between 10.0 microns and 1,000 microns

Poly(N-Isopropylacrylamide) surface-grafted ghitosan membranes as a new substrate for cell sheet engineering and manipulation

The immobilization of poly(N-isopropylacrylamide) (PNIPAAm) on chitosanmembranes was performed in order to render membranes with thermo-responsive surface properties. The aim was to create membranes suitable for cell culture and in which confluent cell sheets can be recovered by simply lowering the temperature. The chitosan membranes were immersed in a solution of the monomer that was polymerized via radical initiation. The composition of the polymerization reaction solvent, which was a mixture of a chitosan non-solvent (isopropanol) and a solvent (water), provided a tight control over the chitosan membranes swelling capability. The different swelling ratio, obtained at different solvent composition of the reaction mixture, drives simultaneously the monomer solubility and diffusion into the polymeric matrix, the polymerization reaction rate, as well as the eventual chain transfer to the side substituents of the pyranosyl groups of chitosan. A combined analysis of the modified membranes chemistry by proton nuclear magnetic resonance (1H-NMR), Fourier transform spectroscopy with attenuated total reflection (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS) showed that it was possible to control the chitosan modification yield and depth in the solvent composition range between 75% and 100% of isopropanol. Plasma treatment was also applied to the original chitosan membranes in order to improve cell adhesion and proliferation. Chitosan membranes, which had been previously subjected to oxygen plasma treatment, were then modified by means of the previously describedmethodology. A human fetal lung fibroblast cell line was cultured until confluence on the plasma-treated thermo-responsive chitosan membranes and cell sheets were harvested lowering the temperature.Contract grant sponsor: European NoE EXPERTISSUESContract grant number: NMP3-CT-2004-500283Contract grant sponsor: European UnionContract grant number: NMP3-CT-2003-50575

Tailoring of 2D-Carbon Materials for Smart-Sensing Applications

This work discusses the oxidation of graphite using a modified Hummers method to produce graphene oxide (GO) suitable for large-scale production and long-term storage, and its further reduction to reduced graphene oxide (rGO) with solvated electrons in liquid ammonia as the reducing agent. These low-temperature processes yield a material with fewer structural defects than any other liquid processed rGO, as confirmed by characterization using UV-vis spectroscopy, XPS, optical and Raman microscopy. This reduction method was developed to allow precise control over the mass ratio of reducing agent to recipient and thus the isolation of materials with a varying defect density. The influence of defects in different amounts is demonstrated by the example of a chemiresistive sensor for the detection of NO2 at ambient temperature using rGO as transducer material. The measured signal responses to NO2 in a concentration range from 1 – 10 ppm vary between sensors fabricated with rGO from different stages of reduction. However, it cannot conclusively be stated that the observed trends originate solely from different material properties, rather than morphological differences, which play a crucial role in electrical sensing, due to largely irreproducible drop-deposition. By means of an optical sensor based on surface-plasmon-resonance imaging (SPRi) it is shown, how the chemical properties, i.e., binding characteristics towards hydrophilic and hydrophobic analytes, can be exploited to produce a label-free and selective sensor through an array of semi-selective materials with different amounts of defects in the form of functional oxygen groups. In this approach the differences in defect density are achieved by mixing GO and rGO in different ratios and dispensing them onto the sensor substrate. The optically similar chemical structure of the materials allows intensity-based signal generation at a fixed angle of incidence and with that online monitoring of the analyte state. A convolutional neural network (CNN) is employed for automatic feature extraction from the obtained images and classification within a system of four purine bases. The superiority of CNN-based analysis over traditional classification methods, like decision trees with manual feature extraction is highlighted. In this regard the inhomogeneity of the material spots holds additional informative value to be evaluated by the model. The trained CNN is able to generalize across measurement conditions and even untrained sensors, showcasing the potential for robust and reusable sensors using GO and rGO