Single radio frequency bucket injection in the 88-Inch Cyclotron using a pulsed high voltage chopper.

A single radio frequency bucket of the 88-Inch Cyclotron is filled using a fast chopper located in the axial line. The bucket then accelerates until it reaches the deflector, at which point, it is extracted as a train of bunches. This phenomenon can be attributed to the characteristic multi-turn extraction of the cyclotron and, by simplifying the complex dynamics of a cyclotron, corresponds to the conceptual transfer function of the cyclotron. The confirmation of the single radio frequency bucket injection was achieved by operating the cyclotron in the third harmonic mode and observing the absence of intermediate bunches during the multiple-bunch extraction.

A Review of Formulations, Boundary Value Problems and Solutions for Numerical Computation of Transcranial Magnetic Stimulation Fields.

Since the inception of the transcranial magnetic stimulation (TMS) technique, it has become imperative to numerically compute the distribution of the electric field induced in the brain. Various models of the coil-brain system have been proposed for this purpose. These models yield a set of formulations and boundary conditions that can be employed to calculate the induced electric field. However, the literature on TMS simulation presents several of these formulations, leading to potential confusion regarding the interpretation and contribution of each source of electric field. The present study undertakes an extensive compilation of widely utilized formulations, boundary value problems and numerical solutions employed in TMS fields simulations, analyzing the advantages and disadvantages associated with each used formulation and numerical method. Additionally, it explores the implementation strategies employed for their numerical computation. Furthermore, this work provides numerical expressions that can be utilized for the numerical computation of TMS fields using the finite difference and finite element methods. Notably, some of these expressions are deduced within the present study. Finally, an overview of some of the most significant results obtained from numerical computation of TMS fields is presented. The aim of this work is to serve as a guide for future research endeavors concerning the numerical simulation of TMS.

Fidelización de usuarios mediante la implantación de un servicio profesional asistido de indicadores para el auto-control del síndrome metabólico / User loyalty through the implementation of a professional service assisted by indicators for the self-monitoring of metabolic syndrome

JUSTIFICACIÓN: el síndrome metabólico (SM) ha tomado gran importancia por su elevada prevalencia y por ser referencia básica para la evaluación de pacientes por los profesionales de la salud. La detección precoz del SM puede evitar complicaciones cardiovasculares y diabetes en aquellos individuos de mayor riesgo. Los parámetros que lo caracterizan son; Al menos 3 de los 5 criterios (glucosa ayunas >110, perímetro abdominal > 110 en hombres y 88 en mujeres, TG >150, colesterol HDL <40 en hombres y 50 en mujeres, Tensión arterial (TA) >130/85), en caso de no poder utilizar perímetro abdominal es aceptable el índice de masa corporal (IMC).OBJETIVO: implantación de un servicio profesional de auto seguimiento del SM en la farmacia comunitaria asistido por el farmacéutico mediante un método de diagnóstico sencillo.MATERIALES Y MÉTODOS: los parámetros analizados en la farmacia fueron Glucosa, Colesterol, triglicéridos (Reflotron® Roche Diagnostics), IMC y TA (Fénix Imvico). Se ofreció el programa a cualquier paciente que quisiera controlar los parámetros de riesgo en el seguimiento de su tratamiento, pacientes con sobrepeso, y/o fumadores. Se crearon unas tarjetas anónimas e individuales de seguimiento con un total de 5 pruebas. Para evaluar la percepción de fidelización de los pacientes, los resultados del estudio fueron correlacionados sin posibilidad de trazabilidad individual, con parámetros de evolución de la actividad de la farmacia (incrementos de facturación y número de operaciones) suministrados por la aplicación farmacéutica (Farmatic), normalizados por los datos generales del sector (informe IQVIA).RESULTADOS: de diciembre de 2019 a julio de 2021 se entregaron 213 tarjetas válidas, 55 % a mujeres y 45 % a varones. La prueba más demandada fue la toma de tensión (355) seguida de la prueba de glucosa (101) y colesterol (93). (AU)

X-ray diagnostics of ECR ion sources-Techniques, results, and challenges.

The high magnetic confinement provided by the minimum-B structure of electron cyclotron resonance ion sources (ECRIS) hosts a non-equilibrium plasma, composed of cold multi-charged ions and hot electrons whose energy can expand up to ≈1 MeV. With a very limited accessibility, the ECR plasma is difficult to study. The x-ray photons generated by the interaction of the warm and hot electron populations within the plasma, as well as the photons generated by electrons lost to the chamber wall, are a signal of great interest as it gives an insight to the properties of the ECR plasma. After an introduction presenting the mechanism generating the x rays in ECRIS, this Review presents the methodology to measure x rays both for volumetric measurements and plasma imaging. The main insights of those measurements are presented. Prospects of x-ray measurements to better understand the plasma dynamics are finally highlighted.

Rango de acción del colocador como indicador de rendimiento en voleibol masculino / Setter’s Action Range as A Performance Indicator in Male Volleyball

Este estudio buscó comprobar si la zona ideal de colocación es la más usada, comparar dicha zona con la Posición Media (AP) del colocador con disponibilidad de primer tiempo y verificar si la distancia entre ambas puede considerarse un indicador de rendimiento. Analizamos 2291 acciones de los 12 mejores equipos del mundial masculino de voleibol (2010). Registramos la posición (latitud y profundidad) del colocador. Calculamos su AP y la distancia a la zona ideal. Recogimos la eficacia de recepción desde las estadísticas de la FIVB. Una correlación aportó la Rho de Spearman. Los resultados confirman el área de latitud 6 y profundidad 1 como la más exitosa, pero los equipos pueden contar con primer tiempo cuando el colocador sale de ella. La distancia entre la AP con disponibilidad de primer tiempo y la zona ideal de colocación correlaciona con la clasificación final más que la eficacia de recepción (AU)

This study aimed to check if the ideal setting zone is the most frequently used, to compare this zone with the Average Position of the setter with middle blocker availability (AP) and to verify if the distance between both can be considered a performance indicator. 2291 actions of the top-12 teams in the 2010 Men’s Volleyball World Championship were analysed. The position (latitude and depth) of the setter was registered. The AP and the distance with the ideal setting zone were calculated. The reception efficacy was retrieved from the FIVB. Spearman’s Rho was obtained through a correlation. Results confirm the area of latitude 6 and depth 1 as the most successful. Nevertheless, teams are able to maintain first tempo availability despite moving the setter out of it. The distance between the AP and the ideal setting zone correlates to the final ranking more than the reception efficacy. (AU)

Pure laparoscopic living donor right hepatectomy (with video).

Only a few centers in the world perform pure laparoscopic right hepatectomy for adult-to-adult living donor liver transplantation. In this procedure, right lobe donation is mostly preferred in view of the higher graft volume usually needed for the recipient. In the area, laparoscopic surgery has had a minor development given the greater technical difficulty and risks for both donor and preservation of the graft. Nevertheless, last 3 years, the advances in major laparoscopic liver surgery suggest that pure laparoscopic right hepatectomy could be a feasible and safe procedure in appropriately selected donors, and mostly, when is performed by surgeons with significant experience in both laparoscopic liver surgery and liver transplantation with living donor liver grafts. This video shows the surgical technique of a pure laparoscopic right hepatectomy in a 30-year-old female volunteered for living donation to her brother.

Fully laparoscopic pancreaticojejunostomy, Puestow procedure (with video).

Chronic pancreatitis usually requires medical treatment and, in rare cases, surgical intervention. The most frequent cause of consultation is chronic pain that is difficult to manage, and therapeutic options such as endoscopy can resolve most problems without surgery. However, when these options fail, surgical management is necessary. The most common surgery is a lateral pancreatic bypass or Puestow surgery. We present the case of a 31-year-old patient with unspecific abdominal discomfort. Abdominal ultrasonography showed significant dilation of the pancreatic duct (18 mm). Abdominal magnetic resonance imaging showed an impacted stone in the head of the pancreas and pancreas divisum. Resolution with endoscopy was attempted, but the pancreatic duct could not be accessed due to impacted lithiasis. After discussion in a multidisciplinary committee, surgical treatment was recommended, and a fully laparoscopic Puestow surgery was performed.

Antibiotic-exposed patients with non-small-cell lung cancer preserve efficacy outcomes following first-line chemo-immunotherapy.

BACKGROUND: Prior antibiotic therapy (pATB) is known to impair efficacy of single-agent immune checkpoint inhibitors (ICIs), potentially through the induction of gut dysbiosis. Whether ATB also affects outcomes to chemo-immunotherapy combinations is still unknown. PATIENTS AND METHODS: In this international multicentre study, we evaluated the association between pATB, concurrent ATB (cATB) and overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) in patients with non-small-cell lung cancer (NSCLC) treated with first-line chemo-immunotherapy at eight referral institutions. RESULTS: Among 302 patients with stage IV NSCLC, 216 (71.5%) and 61 (20.2%) patients were former and current smokers, respectively. Programmed death-ligand 1 tumour expression in assessable patients (274, 90.7%) was ≥50% in 76 (25.2%), 1%-49% in 84 (27.9%) and <1% in 113 (37.5%). Multivariable analysis showed pATB-exposed patients to have similar OS {hazard ratio (HR) = 1.42 [95% confidence interval (CI): 0.91-2.22]; P = 0.1207} and PFS [HR = 1.12 (95% CI: 0.76-1.63); P = 0.5552], compared to unexposed patients, regardless of performance status. Similarly, no difference with respect to ORR was found across pATB exposure groups (42.6% versus 57.4%, P = 0.1794). No differential effect was found depending on pATB exposure duration (≥7 versus <7 days) and route of administration (intravenous versus oral). Similarly, cATB was not associated with OS [HR = 1.29 (95% CI: 0.91-1.84); P = 0.149] and PFS [HR = 1.20 (95% CI: 0.89-1.63); P = 0.222] when evaluated as time-varying covariate in multivariable analysis. CONCLUSIONS: In contrast to what has been reported in patients receiving single-agent ICIs, pATB does not impair clinical outcomes to first-line chemo-immunotherapy of patients with NSCLC. pATB status should integrate currently available clinico-pathologic factors for guiding first-line treatment decisions, whilst there should be no concern in offering cATB during chemo-immunotherapy when needed.

Photocatalytic behavior for the phenol degradation of ZnAl layered double hydroxide functionalized with SDS.

Functionalized ZnAl layered double hydroxide based photocatalyst was obtained by the addition of sodium dodecyl sulfate (SDS) during the synthesis by the coprecipitation method, and further calcination at 400 °C. Bare and modified materials were characterized by X-ray diffraction, nitrogen adsorption-desorption, IR, UV-Vis, EPR and XPS spectroscopies, SEM and HRTEM. The synthesized material was evaluated in the photodegradation of phenol in a 40 ppm aqueous solution (4.25 × 10-4 mol of phenol/L), under UV light irradiation. An increasing in the degradation of phenol from 62 to 95%, and from 62 to 82% in the mineralization of phenol was obtained using SDS functionalized ZnAl LDH, in comparison with the unmodified material. This increase could be attributed to the presence of sulfate radicals, confirmed by the EPR study.

Combination of phenotype and polygenic risk score in breast cancer risk evaluation in the Spanish population: a case -control study.

BACKGROUND: In recent years, the identification of genetic and phenotypic biomarkers of cancer for prevention, early diagnosis and patient stratification has been a main objective of research in the field. Different multivariable models that use biomarkers have been proposed for the evaluation of individual risk of developing breast cancer. METHODS: This is a case control study based on a population-based cohort. We describe and evaluate a multivariable model that incorporates 92 Single-nucleotide polymorphisms (SNPs) (Supplementary Table S1) and five different phenotypic variables and which was employed in a Spanish population of 642 healthy women and 455 breast cancer patients. RESULTS: Our model allowed us to stratify two groups: high and low risk of developing breast cancer. The 9th decile included 1% of controls vs 9% of cases, with an odds ratio (OR) of 12.9 and a p-value of 3.43E-07. The first decile presented an inverse proportion: 1% of cases and 9% of controls, with an OR of 0.097 and a p-value of 1.86E-08. CONCLUSIONS: These results indicate the capacity of our multivariable model to stratify women according to their risk of developing breast cancer. The major limitation of our analysis is the small cohort size. However, despite the limitations, the results of our analysis provide proof of concept in a poorly studied population, and opens up the possibility of using this method in the routine screening of the Spanish population.

High pressure exploration in the Li-Ln-V-O system.

Using in situ high pressure Raman spectroscopy, two structural changes were observed in a sample of the composition LiLa5O5(VO4)2. Taking this into account and by combining different conditions, three new compounds were further obtained from high pressure-high temperature synthesis. Their crystal structure description was done using the antiphase approach, which implies the presence of oxygen-centered [OLn4] building units, where Ln is La for (1) ß-LiLa5O5(VO4)2 and (2) ß-LiLa2O2(VO4) or Nd for (3) LiNd5O5(VO4)2 compounds. (1) crystallizes in the triclinic space group P1[combining macron] with unit cell parameters of a = 5.8167(15) Å, b = 12.2954(28) Å, c = 18.7221(69) Å, α = 102.03(2)°, ß = 98.76(2)°, and γ = 103.54(2)°; a 3D structure was deduced from the ambient pressure polymorph. (2) also crystallizes in P1[combining macron] with a = 5.8144(7) Å, b = 5.8167(7) Å, c = 8.5272(1) Å, α = 98.184(7)°, ß = 100.662(7)° and γ = 92.579(7)°. It shows a 2D structure with [La2O2]2+ layers surrounded by [LiO4] and [VO4] tetrahedra sharing corners and edges. (3) exhibits a 3D architecture isotypic with AP-LiLa5O5(VO4)2. The crucial role of high pressure in such types of synthesis and materials is also discussed.

Elucidating esterification reaction during deposition of cutin monomers from classical molecular dynamics simulations.

The structural behavior of some cutin monomers, when deposited on mica support, was extensively investigated by our research group. However, other events, such as esterification reaction (ER), are still a way to explore. In this paper, we explore possible ER that could occur when these monomers adsorb on support. Although classical molecular dynamics simulations are not able to capture reactive effects, here, we show that they become valuable strategies to analyze the initial structural configurations to predict the most favorable reaction routes. Thus, when depositing aleuritic acid (ALE), it is observed that the loss of capacity to form self-assembled (SA) systems favors different routes to occur ER. In pure ALE bilayers systems, an ER is given exclusively through the -COOH and primary -OH groups. In pure ALE monolayers systems, the ER does not happen when the system is self-assembled. However, for disorganized systems, it is able to occur by two possible routes: -COOH and primary -OH (route 1) and -COOH and secondary -OH (route 2). When palmitic acid (PAL) is added in small quantities, ALE SAMs can now form an ER. In this case, ER occurs mostly through the -COOH and secondary -OH groups. However, when the presence of PAL is dominant, ER can occur with either of both possibilities, that is, routes 1 and 2. Graphical abstract.

Transformation of Nanostructures Cu2O to Cu3Se2 through Different Routes and the Effect on Photocatalytic Properties.

In this work, copper selenide (Cu3Se2 umangite phase) was synthesized by two routes, using a chemical reaction and the hydrothermal method to obtain CuSe-A and CuSe-H, respectively. The synthesis of Cu3Se2 consisted of a three-step process: in the first step, copper(I) oxide hexapods (Cu2O) were obtained as the copper reservoir; in the second step, selenium ions were obtained from the reduction of selenium powder; and in the third step involves mixing two precursors following the two synthesis routes mentioned before. Analysis of X-ray diffraction and X-ray photoelectron spectroscopy showed the formation of the Cu3Se2 phase by both synthesis routes. On the other hand, using the scanning electron microscopy (SEM) technique, it is observed that the Cu3Se2 sample (CuSe-A) is obtained by exchanging in solution with agitation and that the copper selenium phase grows only on the surface of the hexapods. Meanwhile, the hydrothermal route promotes a total conversion of copper(I) oxide hexapods to the copper selenide phase (CuSe-H). The resulting materials were tested as photocatalytic materials to remove methylene blue dye in water under sunlight irradiation. Cu3Se2 (CuSe-H) obtained by the hydrothermal route exhibited a higher efficiency of photodegradation of dye, reaching a removal percentage of 92% after 4 h under sunlight.

Synaptotagmin 13 is neuroprotective across motor neuron diseases.

In amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), spinal and lower brainstem motor neurons degenerate, but some motor neuron subtypes are spared, including oculomotor neurons (OMNs). The mechanisms responsible for this selective degeneration are largely unknown, but the molecular signatures of resistant and vulnerable motor neurons are distinct and offer clues to neuronal resilience and susceptibility. Here, we demonstrate that healthy OMNs preferentially express Synaptotagmin 13 (SYT13) compared to spinal motor neurons. In end-stage ALS patients, SYT13 is enriched in both OMNs and the remaining relatively resilient spinal motor neurons compared to controls. Overexpression of SYT13 in ALS and SMA patient motor neurons in vitro improves their survival and increases axon lengths. Gene therapy with Syt13 prolongs the lifespan of ALS mice by 14% and SMA mice by 50% by preserving motor neurons and delaying muscle denervation. SYT13 decreases endoplasmic reticulum stress and apoptosis of motor neurons, both in vitro and in vivo. Thus, SYT13 is a resilience factor that can protect motor neurons and a candidate therapeutic target across motor neuron diseases.

Evaluation of the effect of 1,3-bis-(4-phenyl-[1,2,3] triazole-1-il)2-propanol in comparison with metronidazole in an in vitro culture of Blastocystis in samples of patients with irritable bowel syndrome.

Metronidazole is the most-used pharmaceutical for the treatment of infection by Blastocystis. However, studies have reported resistance of the microorganism towards this pharmaceutical. In Mexico, studies concerning the prevalence of this parasite and its relationship to Irritable Bowel Syndrome have been carried out. To evaluate the in vitro effect of metronidazole and the compound 1,3-bis-(4-phenyl-[1,2,3] triazole-1-il)2-propanol over Blastocystis, as well as the prevalence of Blastocystis in patients with Irritable Bowel Syndrome. A prospective, transversal design study (April 2016-April 2017) of 51 samples of patients with Irritable Bowel Syndrome, obtained from the ISSEMyM Medical Center in Toluca, Mexico. For the identification of Blastocystis was done in three serial stool samples through direct microscopic examination and the Ritchie technique. The in vitro susceptibility test towards metronidazole and the triazolic compound was done through a microculture in concentrations of 1 to 1000 µg/mL, each one in triplicate. A 31.3% prevalence of Blastocystis was observed in the population, with greater prevalence in women (30.2%) than in men (25%). In the susceptibility test, a CL50 of 64 µg/mL was obtained for metronidazole, in comparison to the CL50 of 250 µg/mL for 1,3-bis-(4-phenyl-[1,2,3] triazole-1-il)2-propanol. This molecule in development has an effect for the treatment of infection by Blastocystis in vitro in patients with IBS and therefore, more studies should be performed.

Immunomodulatory Therapy Does Not Increase the Risk of Cancer in Persons With Inflammatory Bowel Disease and a History of Extracolonic Cancers.

OBJECTIVES: Immunosuppressant therapies (IMTs; thiopurines, anti-tumor necrosis factor agents) may influence the immunologic control of cancer and might facilitate the spread and recurrence of cancer. This study assesses the impact of the use of IMTs on the development of incident cancers (recurrent or new) in patients with inflammatory bowel disease (IBD) and a history of malignancy. METHODS: Patients with IBD included in the ENEIDA registry with a history of cancer without being exposed to IMTs were identified and retrospectively reviewed and compared regarding further treatment with IMTs or not by means of a log-rank test. RESULTS: Overall, 520 patients with previous extracolonic cancer naive to IMTs before the diagnosis of cancer were identified. Of these, 146 were subsequently treated with IMTs (exposed), whereas 374 were not (nonexposed). The proportion of patients with incident cancers was similar in both exposed (16%) and nonexposed (18%) patients (P = 0.53); however, there was more than a 10-year difference in the age at index cancer between these 2 groups. Cancer-free survival was 99%, 98%, and 97% at 1, 2, and 5 years in exposed patients, and 97%, 96%, and 92% at 1, 2, and 5 years in non-exposed patients, respectively (P = 0.03). No differences in incident cancer rates were observed between exposed and nonexposed patients when including only those who were exposed within the first 5 years after cancer diagnosis. DISCUSSION: In patients with IBD and a history of cancer not related to immunosuppression, the use of IMTs is not associated with an increased risk of new or recurrent cancers even when IMTs are started early after cancer diagnosis.

Effectiveness and Safety of the Switch from Remicade® to CT-P13 in Patients with Inflammatory Bowel Disease.

BACKGROUND AND AIMS: To evaluate the clinical outcomes in patients with IBD after switching from Remicade® to CT-P13 in comparison with patients who maintain Remicade®. METHODS: Patients under Remicade® who were in clinical remission with standard dosage at study entry were included. The 'switch cohort' [SC] comprised patients who made the switch from Remicade® to CT-P13, and the 'non-switch' cohort [NC] patients remained under Remicade®. RESULTS: A total of 476 patients were included: 199 [42%] in the SC and 277 [58%] in the NC. The median follow-up was 18 months in the SC and 23 months in the NC [p < 0.01]. Twenty-four out of 277 patients relapsed in the NC; the incidence of relapse was 5% per patient-year. The cumulative incidence of relapse was 2% at 6 months and 10% at 24 months in this group. Thirty-eight out of 199 patients relapsed in the SC; the incidence rate of relapse was 14% per patient-year. The cumulative incidence of relapse was 5% at 6 months and 28% at 24 months. In the multivariate analysis, the switch to CT-P13 was associated with a higher risk of relapse (HR = 3.5, 95% confidence interval [CI] = 2-6). Thirteen percent of patients had adverse events in the NC, compared with 6% in the SC [p < 0.05]. CONCLUSIONS: Switching from Remicade® to CT-P13 might be associated with a higher risk of clinical relapse, although this fact was not supported in our study by an increase in objective markers of inflammation. The nocebo effect might have influenced this result. Switching from Remicade® to CT-P13 was safe.

Understanding segregation processes in SAMs formed by mixtures of hydroxylated and non-hydroxylated fatty acids.

In this paper, we focus on the segregation processes emerging when preparing mixtures with different compositions of aleuritic (9,10,16 trihydroxyhexadecanoic) (ALE) and palmitic (hexadecanoic) (PAL) acids. The combination of atomic force microscopy (AFM) and molecular dynamics (MD) simulations enabled us to prove the role of the functional groups in the formation of self-assembled monolayers (SAMs) on muscovite mica surfaces. MD simulations indicate that segregation processes are favored in high ALE composition mixtures in agreement with the experimental evidence, whereas low ALE compositions promote the co-existence between segregated and dispersed systems. The secondary hydroxyl groups play a central role in the self-assembling mechanism because they control the formation of hydrogen bonding networks guarantying system stability.

Long-Term Safety of In Utero Exposure to Anti-TNFα Drugs for the Treatment of Inflammatory Bowel Disease: Results from the Multicenter European TEDDY Study.

OBJECTIVES: The long-term safety of exposure to anti-tumor necrosis factor (anti-TNFα) drugs during pregnancy has received little attention. We aimed to compare the relative risk of severe infections in children of mothers with inflammatory bowel disease (IBD) who were exposed to anti-TNFα drugs in utero with that of children who were not exposed to the drugs. METHODS: Retrospective multicenter cohort study. Exposed cohort: children from mothers with IBD receiving anti-TNFα medication (with or without thiopurines) at any time during pregnancy or during the 3 months before conception. Non-exposed cohort: children from mothers with IBD not treated with anti-TNFα agents or thiopurines at any time during pregnancy or the 3 months before conception. The cumulative incidence of severe infections after birth was estimated using Kaplan-Meier curves, which were compared using the log-rank test. Cox-regression analysis was performed to identify potential predictive factors for severe infections in the offspring. RESULTS: The study population comprised 841 children, of whom 388 (46%) had been exposed to anti-TNFα agents. Median follow-up after delivery was 47 months in the exposed group and 68 months in the non-exposed group. Both univariate and multivariate analysis showed the incidence rate of severe infections to be similar in non-exposed and exposed children (1.6% vs. 2.8% per person-year, hazard ratio 1.2 (95% confidence interval 0.8-1.8)). In the multivariate analysis, preterm delivery was the only variable associated with a higher risk of severe infection (2.5% (1.5-4.3)). CONCLUSIONS: In utero exposure to anti-TNFα drugs does not seem to be associated with increased short-term or long-term risk of severe infections in children.

The use of an intraarticular catheter on fast-track primary knee arthroplasty, is it a step forward? / Uso de catéter intraarticular en fast track de artroplastia primaria de rodilla. ¿Supone un avance?

OBJECTIVE: This study compares the efficacy in post-operative pain control of the intraarticular catheter compared to the epidural catheter after primary total knee arthroplasty. MATERIAL AND METHOD: Randomised clinical trial consisting of two groups of patients. A control group with intradural anaesthesia and an intraoperative epidural catheter (ropivacaine) and an intervention group using the same anaesthetic technique and an intraarticular catheter with an elastomeric pump (ropivacaine+dexketoprofen). Data such as demographic, anaesthetic and surgical variables, pain intensity according to Verbal Rating Scale, opioid use and complications, joint balance, onset of walking and hospital stay were recorded. RESULTS: A lower incidence and severity on Verbal Rating Scale and a better control of postoperative pain (p<.0014) were observed in the intervention group. Joint balance also presented significant results in flexion and 74% of these patients started walking before the first 36h and the control group had not yet done so. Regarding patient satisfaction, 54.1% of the patients were "very satisfied" with the use of the catheter (p>.001). Finally, the hospital stay decreased significantly, with 33.3% of intervention group patients discharged within the first 48h compared to none of the control group. DISCUSSION AND CONCLUSIONS: The use of the intraarticular catheter as postoperative analgesia is a useful and safe alternative. It reduces the possibility of side effects. It helps in early improvement of joint balance, onset of walking and control of pain. All of which increase patient satisfaction and result in a shorter period of hospitalisation.