International lower limb collaborative (INTELLECT) study: a multicentre, international retrospective audit of lower extremity open fractures

Trauma remains a major cause of mortality and disability across the world1, with a higher burden in developing nations2. Open lower extremity injuries are devastating events from a physical3, mental health4, and socioeconomic5 standpoint. The potential sequelae, including risk of chronic infection and amputation, can lead to delayed recovery and major disability6. This international study aimed to describe global disparities, timely intervention, guideline-directed care, and economic aspects of open lower limb injuries

Processing of membranes and 3D scaffolds based on n-TiO2 colloidally dispersed on a thermoplastic matrix for photocatalytic pollutant removal

[EN] One of the most promising technologies for water treatment today is photocatalytic membrane reactors (PMRs). Manufacturing efficient membranes is still challenging as many factors are involved, like the porosity, specific surface area, nature and size of particles. In this work, a colloidal method to self-support commercial nanoparticles (n-TiO) in a polymeric matrix of polylactic acid (PLA) is proposed allowing the fabrication of 2D and 3D structures with high inorganic content that can be adapted to the PMR configurations. Using a commercial filament of PLA loaded with up to 15 vol% of n-TiO2 as starting point, photocatalytic membranes have been manufactured by FFF. In addition, following a similar process, tapes with n-TiO2 particles up to 15 vol% have been processed by tape casting. Thermal characterisation (DTA) and dynamic rheometry evaluated the commercial filament for printing to determine the conditions used during the thermal extrusion and printing processes. FTIR and XRD technologies were used to determine the chemical interactions of PLA matrices with TiO nanoparticles. Porosity was measured by Archimedes's method for the filaments, by mercury intrusion for the membranes and by optical microscopy for the scaffolds. Finally, the microstructure of the 2D and 3D pieces was evaluated by scanning microscopy. 2D tape cast membranes were compared with individual filaments and 3D printed scaffolds in linear and gyroidal geometries. The catalytic activity results indicate that tape cast membranes show much higher kinetic constants than the individual filaments and the linear and gyroidal scaffolds. Regarding the two different printed scaffolds, in contrast to the kinetic values, gyroidal geometries achieve an average degradation time (t) of 6.1 h, which is a lower value than those observed for linear scaffold geometries. Methyl orange degradation tests after 24 h exposure under UV light showed degradation rates of 98% for membranes, 90% for commercial filaments, 80% for gyroidal scaffolds and 60% for linear patterns. Therefore, these results are promising as a solution for fabricating easily extractable self-supported membranes for water treatment in PMRs.This work has been supported by the Spanish Government (Agencia Estatal de Investigación) through the projects PID2019–106631 GB-C42 (MICRO@Mater) and TED2021–129920B-C41 (EC0FOOTPrint), both cofunded by AEI/10.13039/501100011033/Uni´on Europea NextGenerationEU/PRTR). Pablo Ortega Columbrans acknowledges the Comunidad de Madrid for the industrial doctorate support through the contract IND2022/IND-23603

Biocompatible colloidal feedstock for material extrusion processing of bioceramic-based scaffolds

Nowadays an enormous effort has been made to impulse the incorporation of additive manufacturing (AM) approaches in the biomedical sector. One of the most recognized biomaterials for this end is bioceramics such as hydroxyapatite (HA), but unfortunately, ceramics present a lack of accessible technologies based on AM. Consequently, the development of new methodologies which enable the manufacture of bioceramic-based scaffolds is imperative. A large number of publications on polymer–ceramic composite processed by Material Extrusion are available, so far, the maximum ceramic loading reached is still a parameter to improve. Recently an alternative colloidal processing technique to prepare ceramic-based composite feedstock for material extrusion has been proposed. It has been demonstrated that tailoring the surface of the ceramic particles enables the processing of high ceramic loading composites by AM. This article shows the potential of the colloidal approach to process biocompatible PLA/HA feedstock increasing the homogeneity of the bioceramic phase into the composite. The feedstock characterization shows that HA surface modification makes possible the successful dispersion and the ceramic load increase without modifying the biocompatibility. The ceramic load increase does not modify the melting properties of the polymeric matrix required for the 3D printing process. This methodology allows for the first time the development of a final 3D printed composite structure with contents up to 72 wt% of HA by Material Extrusion. This colloidal approach paves the way to transfer the use of additive manufacturing techniques mainly devoted to polymeric biomaterials to other types of biomaterials such as bioceramics. Highlights: A colloidal approach for 3D printing of PLA/HA composites is proposed. HA surface modification made possible a load increase with high dispersion. The characterization of a PLA/HA feedstock for 3D printing is established. Biocompatible PLA/HA feedstock is processed by AM in customized structures. Colloidal approach allows the processing of 3D structures with 72 wt% of HA. © 2024 The Authors. Polymer Composites published by Wiley Periodicals LLC on behalf of Society of Plastics Engineers.Comunidad de Madrid, Grant/AwardNumber: 2022-T1/IND-23973; SpanishGovernment (Agencia Estatal deInvestigación), Grant/Award Numbers:PID2022-137274NB-C31(3DPOSTPERFORM), TED2021-129920B-C41 (EC0FOOTPrint); FEDER, UE:PID2022-137274NB-C31(3DPOSTPERFORM) European Union“NextGeneration”/PRTR: TED2021-129920B-C41 (EC0FOOTPrint)Peer reviewe