A Novel Methodology to Estimate Bone Mechanical Properties Using Dual-Energy Imaging to Improve Pedicle Screw Fixation.

OBJECTIVE: To develop a methodology to improve the representation of the mechanical properties of a vertebral finite element model (FEM) based on a new dual-energy (DE) imaging technology to improve pedicle screw fixation. METHODS: Bone-calibrated radiographs were generated with dual-energy imaging technology in order to estimate the mechanical properties of the trabecular bone. Properties were included in regions of interest in four vertebral FEMs representing heterogeneity and homogeneity, as a realistic and reference model, respectively. Biomechanical parameters were measured during screw pull-out testing to evaluate pedicle screw fixation. RESULTS: Simulations with property distributions deduced from dual-energy imaging characterization (heterogeneous models) induced an increase in biomechanical indicators versus with a homogeneous representation, implying different behaviors for the subject-specific models. CONCLUSION: The presented methodology allows a patient-specific representation of bone quality in a FEM using new DE imaging technology. Consideration of individualized bone distribution in a spinal FEM improves the perspective of orthopedic surgical planning over otherwise underestimated results using a homogeneous representation.

Medición del Ángulo de Inclinación del Ligamento Cruzado Anterior (LCA). Serie de Casos / Anterior Cruciate Ligament (ACL) Inclination angle measurement. Case Series

Introducción La evaluación de la inclinación del ligamento cruzado anterior(LCA) es útil tanto en pacientes que no han sido llevados a procedimientos reconstructivos para aclarar dudas diagnósticas ante la sospecha de una lesión parcial como para el planeamiento quirúrgico; y en el postoperatorio para evaluar la calidad y efectividad al restaurar las inserciones anatómicas del ligamento. Sin embargo en nuestro medio no existe un referente local de medición ni un entrenamiento en la toma de la misma. Objetivo Medir el ángulo de inclinación del LCA en rodillas sanas de nuestra población, utilizando técnicas de medición por resonancia magnética (RM) entre junio del 2013 y junio del 2017. Métodos Estudio descriptivo tipo serie de casos, se incluyeron los pacientes sometidos a RM en el servicio de radiología de nuestro hospital que fueron leídas como normales. Las mediciones del ángulo de inclinación se tomaron en los planos sagital, coronal y axial. Resultados Se incluyeron 91 pacientes (45% (n=41) Hombres / 55% (n=50) Mujeres). Se encontró un ángulo de inclinación del LCA en el plano sagital con una media de 45.31 (DE: 5.39), en el plano coronal de 70.68 (DE:5.79) y 68.49 (DE:5.61) en el plano axial, sin encontrarse diferencias imagenológicas segmentados por sexo, edad o lateralidad. Discusión No se aprecian diferencias en las imágenes de RM en el ángulo de inclinación en ninguno de los tres planos entre hombres y mujeres, tampoco respecto a lateralidad o grupos de edad. Se obtuvieron resultados que aún no están descritos en la literatura; los obtenidos son similares a los reportados en la literatura

Background The evaluation of the inclination of the anterior cruciate ligament (ACL) is useful to clarify diagnostic doubts in patients who have not been taken to reconstructive procedures and to evaluate the quality and effectiveness of restoring the anatomical attachments of the ligament. after an ACL surgery reconstruction. However, in our environment there is no local measurement reference or training in measuring it inclination angle. The aim of the study is to measure the inclination angle of the ACL in healthy knees of our population, using magnetic resonance (MRI) measurement techniques. Methods A Case Series study was performed, including patients who underwent to knee MRI between June 2013 and June 2017 that were read as normal. Inclination angle measurements of the ACL were taken in the sagittal, coronal, and axial planes. Results 91 patients were included (45% (n=41) Men / 55% (n=50) Women). An ACL inclination angle was found in the sagittal plane with a mean of 45.31 (SD: 5.39), in the coronal plane of 70.68 (SD: 5.79) and 68.49 (SD: 5.61) in the axial plane, with no imaging differences found. segmented by sex, age or laterality. Discussion There are no differences in the MRI images in the angle of inclination in any of the three planes between men and women, neither with regard to laterality or age groups. Results were obtained that have not yet been described in the literature; those obtained are similar to those reported in the literature

Recomendaciones para el uso de la hormona de crecimiento humana recombinante en pacientes pediátricos de talla baja en Colombia / Recommendations for treatment with recombinant human growth hormone in pediatric patients in Colombia

resumen está disponible en el texto completo

Abstract In Colombia there are no guidelines for diagnosis and management of patients with short stature and for the use of recombinant human growth hormone, mainly caused by the diversity of training centers in pediatric endocrinology. In response to this situation, the Asociación Colegio Colombiana de Endocrinología Pediátrica leds the first colombian short stature expert committee in order to standardize the use of human recombinant growth hormone. This work had the participation and endorsement of a consortium of clinical experts representing the Sociedad Colombiana de Pediatría, Secretaría Distrital de Salud de Bogotá- Subred Integrada de Servicios de Salud Suroccidente, Fundación Universitaria Sanitas, Universidad de los Andes and some public and private health institutions in the country, in addition to the participation of methodological experts from the Instituto Global de Excelencia Clínica Keralty. By reviewing the literature and with the best available evidence, we proposed to unify definitions, a diagnostic algorithm, biochemical and dynamic tests with their reference parameters, a description of the considerations about growth hormone use among the indications approved by regulatory agency for medications and food in Colombia and finally a proposal for an informed consent and a medication fact sheet available for parents and patients.

CFTR deletion affects mouse osteoblasts in a gender-specific manner.

Advancements in research and care have contributed to increase life expectancy of individuals with cystic fibrosis (CF). With increasing age comes a greater likelihood of developing CF bone disease, a comorbidity characterized by a low bone mass and impaired bone quality, which displays gender differences in severity. However, pathophysiological mechanisms underlying this gender difference have never been thoroughly investigated. We used bone marrow-derived osteoblasts and osteoclasts from Cftr+/+ and Cftr-/- mice to examine whether the impact of CF transmembrane conductance regulator (CFTR) deletion on cellular differentiation and functions differed between genders. To determine whether in vitro findings translated into in vivo observations, we used imaging techniques and three-point bending testing. In vitro studies revealed no osteoclast-autonomous defect but impairment of osteoblast differentiation and functions and aberrant responses to various stimuli in cells isolated from Cftr-/- females only. Compared with wild-type controls, knockout mice exhibited a trabecular osteopenic phenotype that was more pronounced in Cftr-/- males than Cftr-/- females. Bone strength was reduced to a similar extent in knockout mice of both genders. In conclusion, we find a trabecular bone phenotype in Cftr-/- mice that was slightly more pronounced in males than females, which is reminiscent of the situation found in patients. However, at the osteoblast level, the pathophysiological mechanisms underlying this phenotype differ between males and females, which may underlie gender differences in the way bone marrow-derived osteoblasts behave in absence of CFTR.

¿Es útil fijar las fracturas de Segond para el manejo de la inestabilidad anterolateral de rodilla? A propósito de un caso / Is it worthwhile fixing Segond fractures for the management of anterolateral knee instability? A case report

Introducción El complejo anterolateral de la rodilla es un estabilizador secundario de la rotación tibial interna, su inserción distal esta localizada en el aspecto anterolateral de la tibia proximal y su avulsión es conocida como fractura de Segond, fue descrita hace mas de un siglo por el cirujano francés que le dio su nombre. Es frecuente la asociación de la lesión del ligamento cruzado anterior (LCA) con este complejo, tanto que en la actualidad se considera la fractura de Segond como un signo patognomónico de ruptura del cruzado anterior. Dada la importancia de brindar estabilidad rotacional desde la periferia de la articulación y las propiedades cada vez mas reconocidas de las estructuras anterolaterales, este artículo reporta un caso de fijación directa de la fractura de Segond, en el cual se buscó restituir la anatomía original de la rodilla. Métodos Revisión de la literatura relevante y reporte retrospectivo del caso de un paciente con lesión de LCA y fractura de Segond que fue llevado a reconstrucción de LCA con autoinjerto de HTH y reducción directa y fijación con sutura de anclaje de fractura de Segond por una incisión mínima, con un seguimiento clínico de 4 años. Se aplicaron escalas de valoración subjetiva previo al procedimiento y en el seguimiento postoperatorio. Resultados La inestabilidad anterior y anterolateral posterior al manejo quirúrgico presentó mejoría clínica pasando de tener Lachman IIB a negativo, y Pivot shift grado II a negativo. Las escalas de valoración subjetivas de Lysholm e IKDC mejoraron notablemente de resultados regulares previo al procedimiento a excelentes en el postoperatorio. No presentó complicaciones durante el procedimiento ni requirió reintervenciones. Discusión Aunque la fractura de Segond está descrita desde hace más de un siglo, y su asociación con lesiones de ligamento cruzado anterior se documentó hace mas de 20 años, aun no hay consenso en el manejo de esta fractura. Desde el punto de vista biomecánico, una estructura localizada en el centro de la rodilla como el LCA, de manera aislada, sería insuficiente para controlar la rotación tibial en relación al fémur. Por lo tanto, sería lógico pensar que una estructura localizada lejos del centro de rotación de la rodilla pueda ser más efectiva en controlar la rotación ya que ejerce un mayor control del torque rotacional. Reportamos resultados funcionales satisfactorios y estabilidad postoperatoria adecuada a 4 años de seguimiento, posterior a la fijación de la fractura de Segond asociada a reconstrucción de LCA; consideramos que puede ser una medida exitosa y segura para el manejo de la inestabilidad anterolateral de la rodilla.

Introduction The anterolateral complex of the knee is a secondary stabiliser of the internal tibial rotation. Its distal insertion is located in the anterolateral aspect of the proximal tibia, and its avulsion is known as Segond fracture. This was described more than a century ago by the French surgeon who gave it his name. The combination of anterior cruciate ligament injury (ACL) with the anterolateral complex is so common in as much that Segond fracture is currently considered as a pathognomonic sign of rupture of the anterior cruciate. Given the importance of providing rotational stability from the periphery of the joint and the increasingly recognised properties of the anterolateral structures, this article reports a case of direct fixation of the Segond fracture, in which it was sought to restore the original anatomy of the knee. Methods Review of relevant literature and retrospective case report of a patient with ACL injury and Segond fracture who underwent ACL reconstruction with a host-to-host (HTH) autograft and direct reduction and fixation with Segond fracture anchor suture through a minimal incision. There was a clinical follow-up of 4 years. Subjective assessment scales were applied prior to the procedure and in the postoperative follow-up. Results Anterior and anterolateral instability after surgical management showed a clinical improvement, going from having Lachman IIB to negative, and from Pivot shift grade II to negative. The subjective rating scales of Lysholm and International Knee Documentation Committee (IKDC) improved markedly from regular results prior to the procedure to excellent in the postoperative period. There were no complications during the procedure and no reoperations were required Discussion Although the Segond fracture has been described for more than a century, and its association with anterior cruciate ligament injuries was documented more than 20 years ago, there is still no consensus on the management of this fracture. From the biomechanical point of view, a structure located in the centre of the knee like the ACL, in isolation, would be insufficient to control the tibial rotation in relation to the femur. Therefore, it would be logical to think that a structure located far from the centre of rotation of the knee can be more effective in controlling rotation, since it exerts a greater control of rotational torque. Satisfactory functional results are reported, together with an adequate postoperative stability at 4 years of follow-up, after the fixation of the Segond fracture associated with ACL reconstruction. It is considered that this can be a successful and safe measure for the management of anterolateral instability of the knee.

Abordaje transfibular modificado para fracturas del platillo tibial posterolateral. Serie de Casos / Modified transfibular approach for posterolateral tibial plateau fractures. Case Series

Introducción Las fracturas del platillo tibial posterolateral exigen un abordaje que permita una buena visualización de la superficie articular para su restitución anatómica, restablecimiento de la altura y un espacio adecuado para la aplicación del material de osteosíntesis y fijación estable. Hay diversos abordajes descritos en la literatura que no proporcionan la visualización deseada o conllevan múltiples limitaciones y/o complicaciones. El propósito de este estudio es describir una modificación a la técnica quirúrgica de la osteotomía de la fíbula para el manejo de las fracturas de platillo tibial posterolateral. Materiales y métodos Se presentan los resultados clínicos de una serie de casos retrospectiva de 15 pacientes con fracturas de platillo tibial posterolateral que al momento del estudio tenían un seguimiento promedio de 6 meses. Resultados Los resultados funcionales en escala de Lysholm fueron excelentes en 3 pacientes, buenos en 8 y regulares en 4. En todos los pacientes se logró una reducción satisfactoria de la superficie articular de la tibia, sin pérdida de altura de la misma, con alineación adecuada, sin síntomas de inestabilidad, todos con consolidación de la fíbula que no retrasó la rehabilitación, no hubo lesiones del nervio peroneal ni problemas con la piel; se presentó un caso de infección superficial que se manejó con antibióticos orales sin complicaciones. Discusión El abordaje descrito facilita una amplia exposición de la superficie articular, es técnicamente fácil y reproducible, permite la reducción y fijación necesaria, con menor riesgo de complicaciones, con la cual se conserva el aporte vascular de la tibia proximal, se evita el daño a la articulación tibiofibular proximal y se propicia una mayor área de consolidación de la osteotomía. Ésta técnica puede utilizarse sola o en combinación con otros abordajes, para fracturas agudas o crónicas con mala unión. Consideramos que el abordaje con la técnica descrita es una alternativa para el manejo de las fracturas posterolaterales, con resultados alentadores.

Background Fractures of the posterolateral tibial plateau require an approach that allows a good visualization of the articular surface for its anatomical restitution, restoration of height and an adequate space for the application of osteosynthesis material and stable fixation. There are several approaches described in the literature that do not provide the desired visualization or involve multiple limitations and / or complications. The purpose of this study is to describe a modification to the surgical technique of the fibula osteotomy for the management of posterolateral tibial plate fractures. Methods We present the clinical results of a retrospective case series of 15 patients with posterolateral tibial plate fractures that at the time of the study had an average follow-up of 6 months. Results Functional results in Lysholm scale were excellent in 3 patients, good in 8 and regular in 4. Good results were obtained in all patients with a reduction of the tibia articular surface, without loss of height of the same, with alignment adequate, without symptoms of instability, all with consolidation of the fibula that did not delay rehabilitation, there were no peroneal nerve injuries or problems with the skin; There was a case of superficial infection that was managed with oral antibiotics without complications. Discussion The described approach facilitates a broad exposure of the articular surface, is technically easy and reproducible, allows the necessary reduction and fixation, with a lower risk of complications, with which the vascular supply of the proximal tibia is conserved, the damage is avoided to the proximal tibiofibular joint and a greater area of consolidation of the osteotomy is favored. This technique can be used alone or in combination with other approaches, for acute or chronic fractures with poor union. We consider that the approach with the described technique is an alternative for the management of posterolateral fractures, with encouraging results.

Alpha fodrin and the diagnosis of primary Sjögren's syndrome; experience of a Rheumatology Centre in Bogotá, Colombia

Background and objectives: Primary Sjögren's syndrome is an autoimmune disease where the salivary and exocrine glands do not function correctly. This is caused by lymphocytic infiltrates and neuroendocrine components. The diagnostic criteria in this syndrome have subjective and non-specific elements, but in the last few years the performing of IgA and IgG anti-alpha-fodrin antibodies has been considered as a diagnostic option. The main objective of this article is to evaluate the diagnostic performance of the anti-alpha-fodrin test in patients diagnosed with primary Sjögren's syndrome. Materials and methods: The study included patients with a diagnosis of primary Sjögren's syndrome according to the criteria of the American-European consensus or the consensus of the American College of Rheumatology. These were compared with healthy patients with other non-autoimmune diseases. Results: The IgA type antibody was found to have a sensitivity of 0.18 and specificity of 0.92. The IgG type had a sensitivity of 0.05 and specificity of 0.96. The ROC curve for the IgG test was the closest to the point of greatest theoretical sensitivity and specificity. Discussion: The sensitivity of the test was found to be lower than that reported in other studies. This could be explained by factors such as: diagnostic criteria used, different immunoassay techniques, immunoglobulin evaluated, use of drugs, time of diagnosis, and different populations studied. Conclusion: It is considered that the results regarding the specificity of the test in the population of the present study give it validity as a diagnostic test for primary Sjögren's syndrome, however, anti-alpha-fodrin antibodies have shown low sensitivity in our population, and it is considered that more studies are needed to define the role of these antibodies in this disease.

Antecedentes y objetivos: El síndrome de Sjögren primario es una patología autoinmune en la que se presenta disfunción causada por infiltrados linfocíticos y componentes neuroendocrinos en las glándulas salivales y exocrinas. En esta patología los criterios diagnósticos tienen elementos subjetivos y no específicos, por lo que en los últimos arios se ha considerado la realización de anticuerpos anti alfa fodrina IgA e IgG como una opción diagnóstica. El objetivo principal es evaluar el rendimiento diagnóstico de la prueba anti alfa fodrina en pacientes diagnosticados con síndrome de Sjögren primario. Materiales y métodos: Se buscaron pacientes con diagnóstico de síndrome de Sjögren primario de acuerdo con los criterios del consenso americano-europeo o el consenso del Colegio Americano de Reumatología, los cuales se clasificaron como enfermos, estos se compararon con pacientes sanos, los cuales eran pacientes con otras enfermedades no autoinmunes. Resultados: Se encontró que el anticuerpo de tipo IgA tuvo una sensibilidad de 0,18 y especificidad de 0,92. El de tipo IgG una sensibilidad de 0,05 y especificidad de 0,96. La curva ROC para el test IgG fue la más cercana al punto de mayor sensibilidad y especificidad teóricas. Discusión: Se encontró una menor sensibilidad de la prueba que la reportada en otros estudios, la cual puede ser explicada por factores como: criterios diagnósticos empleados, diferentes técnicas de inmunoensayo, inmunoglobulina evaluada, uso de medicamentos, tiempo de diagnóstico y diferentes poblaciones estudiadas. Conclusión: Se considera que los resultados en cuanto a especificidad de la prueba en la población del presente estudio le otorgan validez como prueba diagnóstica para síndrome de Sjögren primario, sin embargo, los anticuerpos anti alfa fodrina presentan baja sensibilidad en nuestra población por lo que se necesitan más estudios para definir su papel en esta enfermedad.