Pseudoaneurismas femorales en fracturas de cadera. ¿Se puede evitar?

Aunque la aparición de un pseudoaneurisma femoral es infrecuente en el contexto del tratamiento de fracturas pertrocantéreas, debido a su extrema gravedad y a su posible implicación en las causas de mortali - dad, es necesario realizar un diagnóstico temprano y un tratamiento adecuado. Presentamos 3 casos en los que se produjo una lesión de la arteria femoral superficial, y 2 de la arteria femoral profunda, tratados los 3 casos con stents recubiertos. Conclusiones . Se debe tomar en consideración, recti fi car la aducción y rotación interna de la extremidad fracturada una vez colocado el implante, el uso de brocas cortas o con un tope para el momento del en - cerrojado distal, longitud adecuada de los tornillos, controlar el desplazamiento del trocánter menor, o una correcta colocación de los cerclajes femorales, para poder disminuir la incidencia de este tipo de lesiones.Although the appearance of a femoral pseudoaneurysm is uncommon in the context of treatment of trochanteric fractures, due to their extreme gravity and its possible involvement in the causes of death, it is ne - cessary for early diagnosis and appropriate treatment. We report 3 cases in which an injury occurred superficial femoral artery, and 2 of the deep femoral artery, 3 cases treated with stents. Conclusions. It should be taken into consideration, correct adduction and internal rotation of the fractured limb once fitted the implant, the use of short bits or a cap on the distal locking time, proper length screws, control the displacement of the lesser trochanter , or the correct placement of the femoral cerclage, to decrease the incidence of these injuries

Neuropatías del Nervio Cubital a Nivel del codo: factores pronósticos

En el presente trabajo se estudian los factores pronósticos invocados como influyentes en el resultado quirúrgico de las neuropatías del nervio cubital a nivel del codo. Desde 1970 los autores han intervenido 37 lesiones cubitales, que han clasificado según APFELBERG y LARSON. El grupo más frecuente de esta serie ha sido la Parálisis Cubital Tardía (14 casos), siguiéndole en importancia numérica el Síndrome Idiopático del Túnel Cubital (9 casos). La liberación con epineurotomía y transposición subcutánea, ha sido la técnica quirúrgica más veces utilizada (17 veces). En la valoración objetiva de resultados, han utilizado la usada por ADELAAR y colaboradores. Tras el análisis y discusión de los resultados, concluyen que son factores pronósticos negativos en el preoperatorio: la amiotrofía interna; la ausencia de potenciales de fibrilación y la ausencia de potenciales sensitivos evocados. Los resultados globales de la serie han sido satisfactorios, ya que pasamos de un valor medio preoperatorio de lesión moderada de 4 puntos a un valor medio final de 6,5 puntos.The authors have studied the forecast factor called on as influential at the surgical results of neuropathie s of ulnar nerve in the elbow joint. Since 1970, the authors have operated on 37 patients affected by ulnar neuropathies, classified according to APFELBERG and LARSON. 14 cases had a tardy ulnar nerve palsy, 9 case s of cubital tunne l syndrome. The surgical technique more frequent used was epineurotomy and anterior subcutaneous transposition of ulnar nerve (17 cases). They have employed the method of ADELAAR et al. to evaluate the results and they conclude that the factors of bad prognosis are intense amyotrophy, absence of fibrilation potentials and absenc e of evoked sensitive potentials. The results of this group wer e satisfactory, of the average value preoperatory of moderate lession was 4 points, after surgery this was 6,5 points at last

Fijador externo como tratamiento definitivo de fractura de diáfisis femoral en Enfermedad de Paget

El tratamiento de las fracturas en la enfermedad de Paget presenta dificultades para el cirujano, debido a las características patológicas del hueso en este tipo de pacientes. La opción terapéutica de elección en fracturas de diáfisis femoral es el enclavado endomedular, pero a menudo encontramos en esta enfermedad complicaciones que dificultan la técnica quirúrgica. Presentamos el caso de una paciente con fractura de diáfisis femoral en hueso con características pagéticas, en el que por la estrechez del canal y la dureza de las corticales no fue posible realizar en enclavado endomedular, y se optó por el fijador externo como tratamiento definitivo, con buenos resultados radiográficos y funcionales. Tras el primer año de evolución, observamos una buena consoli - dación ósea en la radiografía, y la paciente deambula sin ayuda.The treatment of fractures in Paget's disease presents difficulties for the surgeon because of the pathological features of bone in these patients. The treatment of choice for femoral shaft fractures is intrame - dullary nailing, but often found in this disease, complications that hinder the surgical technique. We report the case of a patient with femoral shaft fracture in bone with pagetic characteristics, in which because of the narrow canal and the hardness of the cortical, intamedullary nailing was not possible. We opted for the external fixator as definitive treatment, with good radiographic and functional results. After the first year of follow up, we see good bone healing on X-ray and the patient ambulate without help

Electroconductive PEDOT nanoparticle integrated scaffolds for spinal cord tissue repair

Background: Hostile environment around the lesion site following spinal cord injury (SCI) prevents the re-establishment of neuronal tracks, thus significantly limiting the regenerative capability. Electroconductive scaffolds are emerging as a promising option for SCI repair, though currently available conductive polymers such as polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) present poor biofunctionality and biocompatibility, thus limiting their effective use in SCI tissue engineering (TE) treatment strategies. Methods: PEDOT NPs were synthesized via chemical oxidation polymerization in miniemulsion. The conductive PEDOT NPs were incorporated with gelatin and hyaluronic acid (HA) to create gel:HA:PEDOT-NPs scaffolds. Morphological analysis of both PEDOT NPs and scaffolds was conducted via SEM. Further characterisation included dielectric constant and permittivity variances mapped against morphological changes after crosslinking, Young’s modulus, FTIR, DLS, swelling studies, rheology, in-vitro, and in-vivo biocompatibility studies were also conducted. Results: Incorporation of PEDOT NPs increased the conductivity of scaffolds to 8.3 × 10–4 ± 8.1 × 10–5 S/cm. The compressive modulus of the scaffold was tailored to match the native spinal cord at 1.2 ± 0.2 MPa, along with controlled porosity. Rheological studies of the hydrogel showed excellent 3D shear-thinning printing capabilities and shape fidelity post-printing. In-vitro studies showed the scaffolds are cytocompatible and an in-vivo assessment in a rat SCI lesion model shows glial fibrillary acidic protein (GFAP) upregulation not directly in contact with the lesion/implantation site, with diminished astrocyte reactivity. Decreased levels of macrophage and microglia reactivity at the implant site is also observed. This positively influences the re-establishment of signals and initiation of healing mechanisms. Observation of axon migration towards the scaffold can be attributed to immunomodulatory properties of HA in the scaffold caused by a controlled inflammatory response. HA limits astrocyte activation through its CD44 receptors and therefore limits scar formation. This allows for a superior axonal migration and growth towards the targeted implantation site through the provision of a stimulating microenvironment for regeneration. Conclusions: Based on these results, the incorporation of PEDOT NPs into Gel:HA biomaterial scaffolds enhances not only the conductive capabilities of the material, but also the provision of a healing environment around lesions in SCI. Hence, gel:HA:PEDOT-NPs scaffolds are a promising TE option for stimulating regeneration for SCI.The authors would like to thank the funding provided by the Irish Research Council through the Irish Research Council Enterprise Partnership Scheme with Johnson and Johnson (EPSPG/2020/78), as well as the Irish Fulbright Commission

Beam test, simulation, and performance evaluation of PbF2_2 and PWO-UF crystals with SiPM readout for a semi-homogeneous calorimeter prototype with longitudinal segmentation

Crilin (Crystal Calorimeter with Longitudinal Information) is a semi-homogeneous, longitudinally segmented electromagnetic calorimeter based on high-$Z$, ultra-fast crystals with UV-extended SiPM readout. The Crilin design has been proposed as a candidate solution for both a future Muon Collider barrel ECAL and for the Small Angle Calorimeter of the HIKE experiment. As a part of the Crilin development program, we have carried out beam tests of small ($10\times10\times40$~mm$^3$) lead fluoride (PbF$_2$) and ultra-fast lead tungstate (PbWO$_4$, PWO) crystals with 120~GeV electrons at the CERN SPS to study the light yield, timing response, and systematics of light collection with a proposed readout scheme. For a single crystal of PbF$_2$, corresponding to a single Crilin cell, a time resolution of better than 25~ps is obtained for $>$3 GeV of deposited energy. For a single cell of \pwo, a time resolution of better than 45~ps is obtained for the same range of deposited energy. This timing performance fully satisfies the design requirements for the Muon Collider and HIKE experiments. Further optimizations of the readout scheme and crystal surface preparation are expected to bring further improvements

Development of an advanced modular setup for the on beam characterization of oriented crystals

Recently, the particle physics community has put an increasing effort in developing radiation detectors and equipment based on oriented crystals. A key feature that distinguishes an oriented crystal from the ordinary matter is the reduc-tion of the radiation length (X0) seen by electrons, positrons and photons crossing the lattice along one of its symmetry axes. This effect has been experimentally ob-served only in the last few decades and with samples limited in number, composition and length. In order to characterize a variety of oriented crystals with a standardized procedure, the STORM Collaboration has developed an advanced modular setup, which allows to study the features of any crystal sample with both electron (or positron) and photon beams. This contribution describes the key elements of this setup, namely silicon strip tracking detectors, plastic scintillators, Silicon Photo -Multipliers (SiPMs) coupled to the crystal under test, a photon calorimeter and an electromagnetic spectrometer

Development of an advanced modular setup for the on beam characterization of oriented crystals

Recently, the particle physics community has put an increasing effort in developing radiation detectors and equipment based on oriented crystals. A key feature that distinguishes an oriented crystal from the ordinary matter is the reduction of the radiation length (X0) seen by electrons, positrons and photons crossing the lattice along one of its symmetry axes. This effect has been experimentally observed only in the last few decades and with samples limited in number, composition and length. In order to characterize a variety of oriented crystals with a standardized procedure, the STORM Collaboration has developed an advanced modular setup, which allows to study the features of any crystal sample with both electron (or positron) and photon beams. This contribution describes the key elements of this setup, namely silicon strip tracking detectors, plastic scintillators, Silicon Photo-Multipliers (SiPMs) coupled to the crystal under test, a photon calorimeter and an electromagnetic spectrometer

A highly-compact and ultra-fast homogeneous electromagnetic calorimeter based on oriented lead tungstate crystals

Progress in high-energy physics has been closely tied to the development of high-performance electromagnetic calorimeters. Recent experiments have demonstrated the possibility to significantly accelerate the development of electromagnetic showers inside scintillating crystals typically used in homogeneous calorimeters based on scintillating crystals when the incident beam is aligned with a crystallographic axis to within a few mrad. In particular, a reduction of the radiation length has been measured when ultrarelativistic electron and photon beams were incident on a high-Z scintillator crystal along one of its main axes. Here, we propose the possibility to exploit this physical effect for the design of a new type of compact e.m. calorimeter, based on oriented ultra-fast lead tungstate (PWO-UF) crystals, with a significant reduction in the depth needed to contain electromagnetic showers produced by high-energy particles with respect to the state-of-the-art. We report results from tests of the crystallographic quality of PWO-UF samples via high-resolution X-ray diffraction and photoelastic analysis. We then describe a proof-of-concept calorimeter geometry defined with a Geant4 model including the shower development in oriented crystals. Finally, we discuss the experimental techniques needed for the realization of a matrix of scintillator crystals oriented along a specific crystallographic direction. Since the angular acceptance for e.m. shower acceleration depends little on the particle energy, while the decrease of the shower length remains pronounced at very high energy, an oriented crystal calorimeter will open the way for applications at the maximum energies achievable in current and future experiments. Such applications span from forward calorimeters, to compact beam dumps for the search for light dark matter, to source-pointing space-borne γ-ray telescopes, to decrease the size and the cost of the calorimeter needed to fully contain e.m. showers initiated by GeV to TeV particles

Influence of the Water Content on the Diffusion Coefficients of Li⁺ and Water across Naphthalenic Based Copolyimide Cation-Exchange Membranes

The transport of lithium ions in cation-exchange membranes based on sulfonated copolyimide membranes is reported. Diffusion coefficients of lithium are estimated as a function of the water content in membranes by using pulsed field gradient (PFG) NMR and electrical conductivity techniques. It is found that the lithium transport slightly decreases with the diminution of water for membranes with water content lying in the range 14 < λ < 26.5, where λ is the number of molecules of water per fixed sulfonate group. For λ < 14, the value of the diffusion coefficient of lithium experiences a sharp decay with the reduction of water in the membranes. The dependence of the diffusion of lithium on the humidity of the membranes calculated from conductivity data using Nernst–Planck type equations follows a trend similar to that observed by NMR. The possible explanation of the fact that the Haven ratio is higher than the unit is discussed. The diffusion of water estimated by 1H PFG-NMR in membranes neutralized with lithium decreases as λ decreases, but the drop is sharper in the region where the decrease of the diffusion of protons of water also undergoes considerable reduction. The diffusion of lithium ions computed by full molecular dynamics is similar to that estimated by NMR. However, for membranes with medium and low concentration of water, steady state conditions are not reached in the computations and the diffusion coefficients obtained by MD simulation techniques are overestimated. The curves depicting the variation of the diffusion coefficient of water estimated by NMR and full dynamics follow parallel trends, though the values of the diffusion coefficient in the latter case are somewhat higher. The WAXS diffractograms of fully hydrated membranes exhibit the ionomer peak at q = 2.8 nm⁻1, the peak being shifted to higher q as the water content of the membranes decreases. The diffractograms present additional peaks at higher q, common to wet and dry membranes, but the peaks are better resolved in the wet membranes. The ionomer peak is not detected in the diffractograms of dry membranes.The authors acknowledge financial support provided by the DGICYT (Dirección General de Investigación Cientifíca y Tecnológica) through Grant MAT2011-29174-C02-02