Using reservoir computing to construct scarred wave functions.

Scar theory is one of the fundamental pillars in the field of quantum chaos, and scarred functions are a superb tool to carry out studies in it. Several methods, usually semiclassical, have been described to cope with these two phenomena. In this paper, we present an alternative method, based on the novel machine learning algorithm known as reservoir computing, to calculate such scarred wave functions together with the associated eigenstates of the system. The resulting methodology achieves outstanding accuracy while reducing execution times by a factor of ten. As an illustration of the effectiveness of this method, we apply it to the widespread chaotic two-dimensional coupled quartic oscillator.

Binding affinity predictions with hybrid quantum-classical convolutional neural networks.

Central in drug design is the identification of biomolecules that uniquely and robustly bind to a target protein, while minimizing their interactions with others. Accordingly, precise binding affinity prediction, enabling the accurate selection of suitable candidates from an extensive pool of potential compounds, can greatly reduce the expenses associated to practical experimental protocols. In this respect, recent advances revealed that deep learning methods show superior performance compared to other traditional computational methods, especially with the advent of large datasets. These methods, however, are complex and very time-intensive, thus representing an important clear bottleneck for their development and practical application. In this context, the emerging realm of quantum machine learning holds promise for enhancing numerous classical machine learning algorithms. In this work, we take one step forward and present a hybrid quantum-classical convolutional neural network, which is able to reduce by 20% the complexity of the classical counterpart while still maintaining optimal performance in the predictions. Additionally, this results in a significant cost and time savings of up to 40% in the training stage, which means a substantial speed-up of the drug design process.

Taking advantage of noise in quantum reservoir computing.

The biggest challenge that quantum computing and quantum machine learning are currently facing is the presence of noise in quantum devices. As a result, big efforts have been put into correcting or mitigating the induced errors. But, can these two fields benefit from noise? Surprisingly, we demonstrate that under some circumstances, quantum noise can be used to improve the performance of quantum reservoir computing, a prominent and recent quantum machine learning algorithm. Our results show that the amplitude damping noise can be beneficial to machine learning, while the depolarizing and phase damping noises should be prioritized for correction. This critical result sheds new light into the physical mechanisms underlying quantum devices, providing solid practical prescriptions for a successful implementation of quantum information processing in nowadays hardware.

Diseño y validación de una escala de adherencia a antineoplásicos orales / Design and validation of an adherence scale to oral antineoplastic drugs

Objetivo: diseñar y validar una escala para medir la adherencia a antineoplásicos orales. Disponer de una herramienta sencilla, validada y aplicable a la rutina asistencial que permitirá detectar e identificar la falta de adherencia para establecer estrategias que permitan mejorarla y optimizar la calidad de los servicios sanitarios.Métodoestudio de validación de una escala diseñada para evaluar la adherencia a antineoplásicos orales en una muestra de pacientes ambulatorios que recogen su medicación en 4 hospitales españoles. Se analizará su validez y fiabilidad, elaborada a partir de un estudio previo de metodología cualitativa, mediante la teoría clásica de los test y el análisis Rasch. Se examinará su funcionamiento, el ajuste de los ítems, la estructura de respuesta y de las personas a las predicciones del modelo, así como la dimensionalidad, la fiabilidad ítem-persona, la adecuación del nivel de dificultad de los ítems a la muestra, y el funcionamiento diferencial de los ítems en función del sexo. (AU)

Objective: To design and validate a questionnaire to measure adherence to oral antineoplastic drugs. The availability of a simple, validated tool that can be applied to routine care will make it possible to detect and identify non-adherence in order to establish strategies to improve adherence and optimize the quality of healthcare services.MethodValidation study of the questionnaire designed to assess adherence to antineoplastic drugs in a sample of outpatients who collect their medication in two Spanish hospitals. Its validity and reliability will be analyzed, based on a previous qualitative methodology study, using classical test theory and Rasch analysis. We will examine its performance, item fit, response structure and person fit to the predictions of the model, as well as dimensionality, item-person reliability, the appropriateness of the level of difficulty of the items to the sample, and the differential performance of the items according to gender.

Design and validation of an adherence scale to oral antineoplastic drugs. / Diseño y validación de una escala de adherencia a antineoplásicos orales.

OBJECTIVE: To design and validate a questionnaire to measure adherence to oral antineoplastic drugs. The availability of a simple, validated tool that can be applied to routine care will make it possible to detect and identify non-adherence in order to establish strategies to improve adherence and optimize the quality of healthcare services. METHOD: Validation study of the questionnaire designed to assess adherence to antineoplastic drugs in a sample of outpatients who collect their medication in two Spanish hospitals. Its validity and reliability will be analyzed, based on a previous qualitative methodology study, using classical test theory and Rasch analysis. We will examine its performance, item fit, response structure and person fit to the predictions of the model, as well as dimensionality, item-person reliability, the appropriateness of the level of difficulty of the items to the sample, and the differential performance of the items according to gender.

[Translated article] Design and validation of a scale to measure adherence to oral antineoplastic drugs.

OBJECTIVE: Design and validate a scale to measure adherence to oral antineoplastic drugs. The availability of a simple, validated tool that can be applied to routine care will make it possible to detect and identify non-adherence in order to establish strategies to improve adherence and optimize the quality of healthcare services. METHOD: Validation study of the scale designed to assess adherence to antineoplastic drugs in a sample of outpatients who collect their medication in two Spanish hospitals. Its validity and reliability will be analyzed, based on a previous qualitative methodology study, using classical test theory and Rasch analysis. We will examine its performance, item fit, response structure and person fit to the predictions of the model, as well as dimensionality, item-person reliability, the appropriateness of the level of difficulty of the items to the sample, and the differential performance of the items according to gender.

Drug-related problems in patients admitted for SARS-CoV-2 infection during the COVID-19 pandemic.

Introduction: Drug-related problems (DRP) are events or circumstances in which drug therapy does or could interfere with desired health outcomes. In December 2019, a new coronavirus, SARS-CoV-2, appeared. Little knowledge about this type of infection resulted in the administration of various drugs with limited use in other pathologies. Evidence about DRP in patients with COVID-19 is lacking. Objective: The aim of the present study is to describe identified cases of DRP and those drugs involved in the first wave of patients with COVID-19, and evaluate associated risk factors. Material and methods: Observational, retrospective study performed in a tertiary university hospital between 14th March 2020 and 31 May 2020 (corresponding to the first COVID-19 wave). We recruited patients admitted during the study period. Exclusion criteria included age < 18 years; admission to critically ill units; and care received either in the emergency room, at-home hospitalization or a healthcare center. Results: A total of 817 patients were included. The mean age was 62.5 years (SD 16.4) (range 18-97), and 453 (55.4%) were male. A total of 516 DRP were detected. Among the patients, 271 (33.2%) presented at least one DRP. The mean DRP per patient with an identified case was 1.9. The prevailing DRPs among those observed were: incorrect dosage (over or underdosage) in 145 patients (28.2%); wrong drug combination in 131 (25.5%); prescriptions not in adherence to the then COVID-19 treatment protocol in 73 (14.1%); prescription errors due to the wrong use of the computerized physician order entry in 47 (9.2%); and incorrect dosage due to renal function in 36 (7%). The logistic regression analysis showed that patients who received only prescriptions of antibacterials for systemic use (J01 ATC group) faced a higher likelihood of experiencing a DRP (OR 2.408 (1.071-5.411), p = 0.033). Conclusion: We identified several factors associated with an increased risk of DRPs, similar to those reported in other pre-pandemic studies, including a prolonged length of stay, higher number of prescribed drugs and antimicrobial administration. The relevance of pharmacists and tools like pharmacy warning systems can help prevent, identify and resolve DRP efficiently.

Novel use of riociguat in infants with severe pulmonary arterial hypertension unable to wean from inhaled nitric oxide.

Introduction: Riociguat, an oral soluble guanylate cyclase stimulator, has been approved for use in adults with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension. However, there is limited data on its therapeutic use in children. Case Presentation: We report the case of two infants with severe suprasystemic pulmonary hypertension who were successfully treated with riociguat after failure to wean off inhaled nitric oxide (iNO) despite combination PAH therapy. Case 1 is a 6-month-old term male with TBX4 deletion who presented with severe hypoxemic respiratory failure and severe PAH immediately after birth. Initial cardiac catheterization showed PVRi 15.5 WU*m2. Marked hypoxemia and PAH persisted despite aggressive therapy with sildenafil, bosentan, intravenous treprostinil, and milrinone. The infant required high doses of inhaled nitric oxide (60 ppm) and manifested significant post-ductal hypoxemia and hemodynamic instability with any attempt at weaning. After discontinuation of sildenafil, initiation, and very slow uptitration of riociguat, the patient was able to maintain hemodynamic stability and wean from nitric oxide over 6 weeks with persistently severe but not worsened pulmonary hypertension. Case 2 is a 4-month-old term male with compound heterozygous SLC25A26 mutation and severe pulmonary hypertension. Initial cardiac catheterization showed PVRi 28.2 WU*m2. After uptitration of sildenafil, bosentan, and IV treprostinil, serial echocardiograms continued to demonstrate near-systemic pulmonary hypertension. He failed multiple attempts to wean off typical doses of iNO (10-20 ppm) over the following weeks with tachypnea, hypoxemia, and worsening pulmonary hypertension on echocardiogram despite continued aggressive combination targeted therapy. After a 24-h sildenafil washout, he was initiated and uptitrated on riociguat with concomitant, successful wean of nitric oxide over one week that was well tolerated. No serious adverse effects in the titration period were observed. Conclusion: Riociguat may be considered as an adjuvant therapeutic agent in selected children with severe PAH who are poorly responsive to sildenafil therapy and unable to wean from iNO.

Optimal quantum reservoir computing for the noisy intermediate-scale quantum era.

Universal fault-tolerant quantum computers require millions of qubits with low error rates. Since this technology is years ahead, noisy intermediate-scale quantum (NISQ) computation is receiving tremendous interest. In this setup, quantum reservoir computing is a relevant machine learning algorithm. Its simplicity of training and implementation allows to perform challenging computations on today's available machines. In this Letter, we provide a criterion to select optimal quantum reservoirs, requiring few and simple gates. Our findings demonstrate that they render better results than other commonly used models with significantly less gates and also provide insight on the theoretical gap between quantum reservoir computing and the theory of quantum states' complexity.

Adapting reservoir computing to solve the Schrödinger equation.

Reservoir computing is a machine learning algorithm that excels at predicting the evolution of time series, in particular, dynamical systems. Moreover, it has also shown superb performance at solving partial differential equations. In this work, we adapt this methodology to integrate the time-dependent Schrödinger equation, propagating an initial wavefunction in time. Since such wavefunctions are complex-valued high-dimensional arrays, the reservoir computing formalism needs to be extended to cope with complex-valued data. Furthermore, we propose a multi-step learning strategy that avoids overfitting the training data. We illustrate the performance of our adapted reservoir computing method by application to four standard problems in molecular vibrational dynamics.

Impact of the implementation of a Sepsis Code Program in medical patient management: a cohort study in an Internal Medicine ward.

OBJECTIVE: Sepsis is the main cause of death in hospitals and the implementation of diagnosis and treatment bundles has shown to improve its evolution. However, there is a lack of evidence about patients attended in conventional units. METHODS: A 3-year retrospective cohort study was conducted. Patients hospitalized in Internal Medicine units with sepsis were included and assigned to two cohorts according to Sepsis Code (SC) activation (group A) or not (B). Baseline and evolution variables were collected. RESULTS: A total of 653 patients were included. In 296 cases SC was activated. Mean age was 81.43 years, median Charlson comorbidity index (CCI) was 2 and 63.25% showed some functional disability. More bundles were completed in group A: blood cultures 95.2% vs 72.5% (p <0.001), extended spectrum antibiotics 59.1% vs 41.4% (p < 0.001), fluid resuscitation 96.62% vs 80.95% (p < 0.001). Infection control at 72 hours was quite higher in group A (81.42% vs 55.18%, odds ratio 3.55 [2.48-5.09]). Antibiotic was optimized more frequently in group A (60.77% vs 47.03%, p 0.008). Mean in-hospital stay was 10.63 days (11.44 vs 8.53 days, p < 0.001). Complications during hospitalization appeared in 51.76% of patients, especially in group B (45.95% vs 56.58%, odds ratio 1.53 [1.12-2.09]). Hospital readmissions were higher in group A (40% vs 24.76%, p < 0.001). 28-day mortality was significantly lower in group A (20.95% vs 42.86%, odds ratio 0.33 [0.23-0.47]). CONCLUSIONS: Implementation of SC seems to be effective in improving short-term outcomes in IM patients, although therapy should be tailored in an individual basis.

Perceptions from nurses, surgeons, and anesthetists about the use and benefits of the surgical checklist in a teaching hospital.

OBJECTIVE: To assess attitudes and perceptions from nursing staff, surgeons and anesthetists about compliance, utility, and impact on patient's safety of the surgical checklist in a teaching hospital. We also aimed to identify improvement opportunities for strengthening the usefulness of the checklist in the operating theater. METHODS: We carried out a questionnaire-based an observational cross-sectional study. A questionnaire was distributed to operating room staff, including nursing staff, surgeons, and anesthetists. In addition to the information about surgical checklist, We also collected information regarding years of experience in the operating theater. Fisher's exact was used to compare proportions in each statement. Group discussion meetings with key professionals were held to jointly assess the results, propose improvement actions, and evaluate their feasibility. RESULTS: The overall response rate was 36.2% (131/362). Nursing staff was perceived as the most supportive group in the use of surgical checklist. A 64.3% of surgeons considered that using the checklist prevented adverse events vs 84.2% and 85.7% among anesthetists and nurses, respectively; p=0.028. Junior staff showed a supportive attitude toward the use of surgical checklist, considering it as a tool that gives them confidence. We ended up with a list of improvement actions aiming at strengthening the surgical checklist reliability and compliance. CONCLUSIONS: The perception of the surgical checklist usefulness as a tool to prevent adverse events was moderate among surgeons, but well appreciated by junior staff. Nursing staff were especially critical regarding compliance and support by other professionals. To reinforce the usefulness perception of the surgical checklist it is needed to increase the involvement of all professionals, especially senior staff and surgical leaders.

Artroplastias primarias de cadera implantadas en Cataluña: ¿qué evidencia clínica respalda a nuestras prótesis? / Primary total hip arthroplasty in Catalonia: What is the clinical evidence that supports our prosthesis?

Introducción: la cumplimentación de registros sobre la implantación de prótesis permite obtener una gran cantidad de datos y extraer conclusiones que redundan en la mejora de la utilización de las mismas. Suecia fue el primer país en implantar un sistema de registro de artroplastias en 1979. Cataluña lo viene haciendo desde el año 2005. El objetivo de nuestro trabajo es analizar la evidencia que respalda a las prótesis implantadas en artroplastias totales de cadera primarias en Cataluña en los últimos 9 años sobre la base del Registro de Artroplastias de Cataluña (RACat). Material y métodos: se realizó una revisión en la literatura de las prótesis (cotilos/vástagos) registrados en el RACat entre los años 2005-2013 en las siguientes bases datos: Orthopaedic Data Evaluation Panel (ODEP), Tripdatabase, Pubmed, Google académico. Se excluyeron aquellas prótesis implantadas en número inferior a 10 unidades (182 cotilos correspondientes a 49 modelos/228 vástagos correspondientes a 63 modelos). Resultados: de los 18.816 cotilos implantados, se analizaron 18.634 (el 99%), correspondientes a 74 modelos diferentes. En 18 modelos (2.527 cotilos) no se encontraron evidencias clínicas que respalden su uso. De los 19.595 vástagos implantados se analizaron 19.367 (el 98,84%), correspondientes a 75 modelos diferentes. En 16 modelos (1.845 vástagos) no se encontraron evidencias clínicas que respalden su uso. En los 56 modelos de cotilos (16.107) y los 59 modelos de vástagos (17.522) restantes las evidencias variaron en función del número de pacientes y los años de seguimiento, predominando los estudios con nivel de evidencia iv. Conclusiones: existe un número significativo de prótesis implantadas evaluadas (13,56% cotilos/9,5% vástagos) en los que no se han encontrado evidencias clínicas. Cabe destacar el alto número de modelos (49 tipos para cotilos/63 tipos para vástagos) con una implantación inferior a 10 unidades que corresponden únicamente al 1% del total. La implantación de registros de artroplastias se revela como una herramienta extremadamente útil al permitirnos analizar y extraer conclusiones para la evaluación y el seguimiento poscomercialización

Introduction: the implementation of National Prostheses Registries allows us to obtain a large amount of data and make conclusions in order to improve the use of them. Sweden was the first country to implement a National Prostheses Registry in 1979. Catalonia has been doing this since 2005. The aim of our study is to analyse the evidence that supports primary total hip replacement in Catalonia in the last 9 years, based on the Arthroplasty Registry of Catalonia (RACat). Material and methods: a review of the literature was carried out of the prosthesis (acetabular cups/stems) reported in the RACat between the period 2005 to 2013 in the following databases: ODEP (Orthopaedic Data Evaluation Panel), TRIP database, PubMed, and Google Scholar. Those prostheses implanted in less than 10 units (182 acetabular components corresponding to 49 models/228 stems corresponding to 63 models) were excluded. Results: a total of 18,634 (99%) implanted acetabular cups were analysed out of a total number of 18,816, corresponding to 74 different models. In 18 models (2527 acetabular cups) no clinical evidence to support its use was found. An analysis was performed on 19,367 (98.84%) out of a total number of 19,595 implanted stems, corresponding to 75 different models. In 16 models (1845 stems) no clinical evidence was found to support their use. Variable evidence was found in the 56 models of acetabular cups (16,107) and 59 models of stems (17,522), most of it corresponding to level iv clinical evidence. Conclusions: there was a significant number implanted prostheses evaluated (13.56% acetabular cups/9.5% stems) for which no clinical evidence was found. The elevated number of models is highlighted (49 types for acetabular cups/63 types for stems) with less than 10 units implanted, which corresponds to only 1% of the total implants. The use of arthroplasty registers is shown to be an extremely helpful tool that allows analyses and conclusions to be made for the follow-up and post-marketing surveillance period

Una década del Registro de Artroplastias de Cataluña (RACat): exhaustividad, variabilidad y supervivencia de las prótesis entre 2005 y 2014 / A decade of the Catalonian Arthroplasty Register (RACat): variability, exhaustivity, and survival of prostheses between 2005 and 2014

Antecedentes y objetivo. El Registro de Artroplastias de Cataluña (RACat) es un registro poblacional basado en el sistema sanitario público para analizar y evaluar artroplastias de cadera y rodilla en Cataluña. El objetivo de este estudio es presentar los resultados tras 10 años de funcionamiento (de enero de 2005 a diciembre de 2014). Metodología. A partir de la información del RACat y del conjunto mínimo básico de datos al alta hospitalaria, se analizó la calidad y exhaustividad de los datos y se realizaron análisis descriptivos de pacientes, prótesis y proceso asistencial. Además, se analizó la supervivencia calculando la incidencia acumulada de revisión (según causa de intervención en artroplastias de cadera y preservación o sacrificio del ligamento cruzado posterior en artroplastia de rodilla) y la asociación entre riesgo de revisión y técnica de fijación de las prótesis como modelos de riesgos competitivos ajustados por sexo, edad y comorbilidad. Resultados. El principal motivo de intervención en artroplastias primarias de cadera y rodilla fue la artrosis. La incidencia acumulada de revisión a los 10 años fue del 3,9% en artroplastias de cadera causadas por artrosis y del 2,3% en las causadas por fractura. Las artroplastias de rodilla que conservan el ligamento cruzado posterior son el 4,4% y las que no lo conservan, el 5,1%. Discusión. El RACat se consolida como herramienta para la evaluación de las artroplastias con gran potencial en el análisis de la efectividad a medio y largo plazo, el estudio de la variabilidad de la práctica clínica y la vigilancia poscomercialización (AU)

Background and aim. The Catalonian Arthroplasty Register (RACat) is a public health-based population register used to analyse and evaluate hip and knee replacements in Catalonia. The aim of this study is to present the outcomes after 10 years in operation (January 2005-December 2014). Methodology. Using the information from the RACat and the minimum basic data set at hospital discharge, an analysis was made of the quality and exhaustivity of the data, as well as a descriptive analysis of the patients, prostheses, and care process. Survival was also analysed by calculating the accumulated incidence of revisions (according to the cause of intervention in hip replacements and conservation or sacrifice of the posterior cruciate ligament in knee replacement). The relationship between revision risk and the fixation technique of the prosthesis is also analysed, using competitive risk models adjusted for gender, age, and comorbidities. Results. The main reason for the primary hip and knee replacement surgery was arthrosis. The accumulated incidence of revisions at 10 years was 3.9% in hip replacements caused by arthrosis, and 2.3% in those caused by fracture. Conservation of the posterior cruciate ligament was achieved in 4.4% of knee replacements, with sacrifice in 5.1%. Discussion. The RACat is consolidated as a tool for the evaluation of joint replacements, with great potential in the analysis of medium and long-term efficacy, the study of the variability in clinical practice, and post-marketing surveillance (AU)

A decade of the Catalonian Arthroplasty Register (RACat): Variability, exhaustivity, and survival of prostheses between 2005 and 2014. / Una década del Registro de Artroplastias de Cataluña (RACat): exhaustividad, variabilidad y supervivencia de las prótesis entre 2005 y 2014.

BACKGROUND AND AIM: The Catalonian Arthroplasty Register (RACat) is a public health-based population register used to analyse and evaluate hip and knee replacements in Catalonia. The aim of this study is to present the outcomes after 10 years in operation (January 2005-December 2014). METHODOLOGY: Using the information from the RACat and the minimum basic data set at hospital discharge, an analysis was made of the quality and exhaustivity of the data, as well as a descriptive analysis of the patients, prostheses, and care process. Survival was also analysed by calculating the accumulated incidence of revisions (according to the cause of intervention in hip replacements and conservation or sacrifice of the posterior cruciate ligament in knee replacement). The relationship between revision risk and the fixation technique of the prosthesis is also analysed, using competitive risk models adjusted for gender, age, and comorbidities. RESULTS: The main reason for the primary hip and knee replacement surgery was arthrosis. The accumulated incidence of revisions at 10 years was 3.9% in hip replacements caused by arthrosis, and 2.3% in those caused by fracture. Conservation of the posterior cruciate ligament was achieved in 4.4% of knee replacements, with sacrifice in 5.1%. DISCUSSION: The RACat is consolidated as a tool for the evaluation of joint replacements, with great potential in the analysis of medium and long-term efficacy, the study of the variability in clinical practice, and post-marketing surveillance.

Virtual Planning and Allograft Preparation Guided by Navigation for Reconstructive Oncologic Surgery: A Technical Report.

INTRODUCTION: Advanced virtual simulators can be used to accurately detect the best allograft according to size and shape. STEP 1 ACQUISITION OF MEDICAL IMAGES: Obtain a multislice CT scan and a magnetic resonance imaging (MRI) scan preoperatively for each patient; however, if the time between the scans and the surgery is >1 month, consider repeating the MRI because the size of the tumor may have changed during that time. STEP 2 SELECT AN ALLOGRAFT USING VIRTUAL IMAGING TO OPTIMIZE SIZE MATCHING: Load DICOM images into a virtual simulation station (Windows 7 Service Pack 1, 64 bit, Intel Core i5/i7 or equivalent) and use mediCAS planning software ( medicas3d.com ) or equivalent (Materialise Mimics or Amira software [FEI]) for image segmentation and virtual simulation with STL (stereolithography) files. STEP 3 PLAN AND OUTLINE THE TUMOR MARGINS ON THE PREOPERATIVE IMAGING: Determine and outline the tumor margin on manually fused CT and MRI studies using the registration tool of the mediCAS planning software or equivalent (Materialise Mimics software.). STEP 4 PLAN AND OUTLINE THE SAME OSTEOTOMIES ON THE ALLOGRAFT: Determine and outline the osteotomies between host and donor using the registration tool of the mediCAS planning software or equivalent (Materialise Mimics software.). STEP 5 ASSESS THE PATIENT AND ALLOGRAFT IN A VIRTUAL SCENARIO: Be sure to consider the disintegration of bone tissue that occurs during the osteotomy and corresponds to the thickness of the blade (approximately 1.5 mm). STEP 6 NAVIGATION SETTINGS: A tool of the mediCAS planning software allows the virtual preoperative planning (STL files) to be transferred to the surgical navigation format, DICOM files. STEP 7 PATIENT AND ALLOGRAFT INTRAOPERATIVE NAVIGATION: The tumor and allograft are resected using the navigated guidelines, which were previously planned with the virtual platform. RESULTS: The 3D virtual preoperative planning and surgical navigation software are tools designed to increase the accuracy of bone tumor resection and allograft reconstruction3.

Primary total hip arthroplasty in Catalonia: What is the clinical evidence that supports our prosthesis? / Artroplastias primarias de cadera implantadas en Cataluña: ¿qué evidencia clínica respalda a nuestras prótesis?

INTRODUCTION: The implementation of National Prostheses Registries allows us to obtain a large amount of data and make conclusions in order to improve the use of them. Sweden was the first country to implement a National Prostheses Registry in 1979. Catalonia has been doing this since 2005. The aim of our study is to analyse the evidence that supports primary total hip replacement in Catalonia in the last 9 years, based on the Arthroplasty Registry of Catalonia (RACat). MATERIAL AND METHODS: A review of the literature was carried out of the prosthesis (acetabular cups/stems) reported in the RACat between the period 2005 to 2013 in the following databases: ODEP (Orthopaedic Data Evaluation Panel), TRIP database, PubMed, and Google Scholar. Those prostheses implanted in less than 10 units (182 acetabular components corresponding to 49 models/228 stems corresponding to 63 models) were excluded. RESULTS: A total of 18,634 (99%) implanted acetabular cups were analysed out of a total number of 18,816, corresponding to 74 different models. In 18 models (2527 acetabular cups) no clinical evidence to support its use was found. An analysis was performed on 19,367 (98.84%) out of a total number of 19,595 implanted stems, corresponding to 75 different models. In 16 models (1845 stems) no clinical evidence was found to support their use. Variable evidence was found in the 56 models of acetabular cups (16,107) and 59 models of stems (17,522), most of it corresponding to level iv clinical evidence. CONCLUSIONS: There was a significant number implanted prostheses evaluated (13.56% acetabular cups/9.5% stems) for which no clinical evidence was found. The elevated number of models is highlighted (49 types for acetabular cups/63 types for stems) with less than 10 units implanted, which corresponds to only 1% of the total implants. The use of arthroplasty registers is shown to be an extremely helpful tool that allows analyses and conclusions to be made for the follow-up and post-marketing surveillance period.

[Low grade parosteal osteosarcoma. Clinical and oncological outcomes]. / Osteosarcoma parostal de bajo grado. Evolución oncológica y clínica.

The objective of the study was to analyze a group of patients with low grade parosteal osteosarcoma treated with limb salvage surgery and reconstructed with bone allograft. A retrospective review from our oncologic data base between 1980 and 2010 was done and all patients with diagnosis of low grade parosteal osteosarcoma, treated with limb salvage surgery and reconstructed with allograft were included. Twenty-two patients were included for the analysis. The mean age was 32±11 years (10-59) y the mean follow-up 93±69 months (8-237). Ten year overall survival of the series was 91% (95% CI: 79-100). Four patients developed local recurrence, 2 of them histological classified after the resection dedifferentiated parosteal osteosarcoma. Two patients developed distant recurrence, being the lung the only site of metastasis. Ten year limb salvage reconstruction survival was 65% (95% CI: 44-86). Long term survival rate in low grade parosteal osteosarcoma is over 90%. Surgical resection wide margin should be the elective treatment and biological limb salvage reconstruction is a good alternative.

Use of Massive Allografts to Manage Hydatid Bone Disease of the Femur.

Hydatid disease is caused by the parasitic tapeworm Echinococcus granulosus. Osseous involvement accounts for 0.5% to 4% of cases in humans. Patients usually are from endemic zones and are initially asymptomatic, presenting with pain and edema at a later stage of disease. However, large lesions may present initially as pathologic fractures. Standard radiographs usually show expansive osteolytic lesions associated with initial cortical thinning, with compromise of the metaphysis or epiphysis, and may involve the diaphysis. The finding of periosteal reaction, osteocondensation, calcification, and clear delimitation of the lesions excludes the diagnosis of osseous hydatidosis. However, there are no specific radiographic signs in the affected bone. There is no generally accepted treatment algorithm for osseous hydatid disease. The usual treatment is surgical resection of the affected bone, followed by antihelmintic therapy. Some patients can be treated with intralesional procedures, such as curettage and allograft or polymethyl methacrylate cement. However, in some advanced cases, such as those with pathologic fractures or recurrences, wide resection may be needed. Several reconstructive alternatives have been reported, such as megaprosthesis, massive allograft, or alloprosthesis composite. The authors retrospectively reviewed 2 cases of femoral hydatidosis treated with wide resection and reconstruction with massive bone allograft. One patient had 5 years of follow-up, and the other had 9 years. No signs of relapse or complications were recorded, and functional outcomes evaluated with the Musculoskeletal Tumor Society scale showed excellent results. These 2 cases support the use of a massive bone allograft as a valid alternative to reconstruction after extensive bone resection for hydatidic disease.