Alejandro Quiroga-Garza

A new Morphological Classification of the Anterior Inferior Iliac Spine: Relevance in Subspine Hip Impingement

El Sindrome de Pinzamiento Femoroacetabular (PFA) es una entidad clinica reconocida en los ultimos anos como una causa de dolor y desarrollo de artrosis temprana de cadera. El pinzamiento subespinoso de la cadera se caracteriza por una espina iliaca anteroinferior (EIAI) prominente o con una morfologia anormal, lo que contribuye al desarrollo de un cuadro clinico similar al PFA. El objetivo fue proponer una nueva clasificacion morfologica de la EIAI y determinar las prevalencias de las distintas morfologias de la EIAI en base a la misma y correlacionarla con los distintos sexos y grupos de edad. La muestra consistio en un total de 458 hemipelvis, de sexo y edad conocidos (264 hombres y 194 mujeres). Cada pieza fue analizada para determinar la prevalencia de variaciones morfologicas de la EIAI en base a la clasificacion propuesta. Tipo 1: presencia de una superficie concava entre la EIAI y reborde acetabular, Tipo 2A: presencia de una superficie plana entre la EIAI y el reborde acetabular, Tipo 2B: presencia de una superficie convexa entre la EIAI y el reborde acetabular y Tipo 3: la EIAI protruye hacia el acetabulo anterior o inferiormente. Se determino una prevalencia de 69,87% para la EIAI Tipo 1 (320/458). En cuanto a las morfologias anormales, se determino una prevalencia de 17,90% (82/458), 3,71% (17/458) y 8,52% (39/459) para los Tipos 2A, 2B y 3, respectivamente. La prevalencia de una morfologia anormal en las EIAI de especimenes del sexo masculino fue de 30,30% (80/264) y en el sexo femenino 29,90% (58/194). Se evidencia la prevalencia de las diferentes morfologias que puede tener la EIAI; esta informacion sera de ayuda para determinar el papel de la EIAI en la aparicion del pinzamiento subespinoso de la cadera.

Morphological Analysis of Major Segments of Coronary Artery Occlusion: Importance in Myocardial Revascularization Surgery

En la cirugia de revascularizacion miocardica se debe asegurar la similitud morfologica entre la arteria coronaria y el injerto. Esto es un factor importante en su duracion y permeabilidad. El objetivo fue analizar las caracteristicas morfologicas y morfometricas de los segmentos de mayor oclusion de las arterias coronarias. Estudio observacional, transversal y descriptivo que consto de dos fases. Una macroscopica en la que se extrajeron 11 corazones de cadaveres y se determino la dominancia coronaria y longitud de la arteria interventricular anterior (AIA), la arteria coronaria derecha (ACD) y la arteria circunfleja (ACX). En la fase microscopica se obtuvo un total de 77 segmentos de estas arterias y se determino el diametro luminal, grosor de pared, cantidad de fibras elasticas y presencia y tamano de ateroma. La dominancia coronaria derecha fue la mas frecuente. La longitud total de los vasos fue de 15,65±1,17 cm para la AIA, de 12,67±2,02 cm para la ACD y 8,79±2,5 cm para la ACX. Los diametros oscilaron entre los 2,3 mm en los segmentos proximales y entre 1,1 mm a 1,8 mm en los segmentos distales. Los grosores de pared en los segmentos proximales se presentaron entre 354 µm y 396 µm y en los segmentos distales oscilaron entre 120 µm a 305 µm. La cantidad de fibras elasticas demostro que son arterias musculares. El 35% de los ateromas se presento en la ACX y el 32,5% en la AIA al igual que en la ACD. Los de mayor tamano se encontraron en los segmentos proximales. Este estudio analizo la morfologia y la morfometria de los segmentos de las arterias coronarias que se ocluyen con mayor frecuencia. Los resultados encontrados aporta informacion sobre los parametros mas significativos que se deben considerar para la eleccion del injerto vascular en la cirugia de revascularizacion miocardica.

Conduits Used in Coronary Artery Bypass Grafting: A Review of Morphological Studies

There is a significant variety of vascular conduits options for coronary bypass surgery. Adequate graft selection is the most important factor for the success of the intervention. To ensure durability, permeability, and bypass function, there must be a morphological similarity between the graft and the coronary artery. The objective of this review was to analyze the morphological characteristics of the grafts that are most commonly used in coronary bypass surgery and the coronary arteries that are most frequently occluded. We included clinical information regarding the characteristics that determine the behavior of the grafts and its permeability over time. Currently, the internal thoracic artery is the standard choice for bypass surgery because of the morphological characteristics of the wall that makes less prone to developing atherosclerosis and hyperplasia. The radial and right gastroepiploic arteries are the following second and third best options, respectively. The ulnar artery is the preferred choice when other conduits are not feasible.

Neurovascular structures at risk during anterolateral and medial arthroscopic approaches of the hip

El objetivo fue describir las areas de seguridad para la colocacion de 5 portales estandar (portal anterior, anterolateral, posterolateral, portal anterior proximal medial y portal anterior distal medial) y 3 portales mediales emergentes (antero medial, portal posteromedial y posteromedial distal) para proporcionar una descripcion topografica de la seguridad de cada portal. Se realizo un estudio descriptivo, observacional y transversal, en la que se diseco el triangulo femoral de 12 caderas. Se colocaron los 5 portales laterales y los 3 portales mediales. Se documento la medicion de cada estructura neurovascular de relevancia clinica en relacion a cada uno de los portales evaluados. En cuanto al portal de mayor riesgo entre los laterales, se encontro el portal anterior con mayor cercania al nervio cutaneo femoral lateral (1,42±0,85 cm), ubicado lateral al portal. En los portales mediales el portal anterior medial tiene el margen mas estrecho respecto a la arteria femoral (2,14±0,35 cm) lateral al portal, y medial el nervio obturador (0,87±0,62 cm). Los portales laterales tienen un amplio margen de seguridad, el portal con el margen mas reducido es el portal anterior en relacion al nervio cutaneo femoral lateral, presentando un elevado riesgo de lesionarlo, los portales mediales tienen un alto riesgo de lesionar las estructuras neurovasculares femorales y el nervio obturador.

Efficacy and safety of adjuvant recombinant human erythropoietin and ferrous sulfate as treatment for iron deficiency anemia during the third trimester of pregnancy

PURPOSE Gestational anemia increases the incidence of maternal and fetal complications. Adjuvant recombinant human erythropoietin (rHuEPO) has been used in patients who refuse blood transfusions, have a low response to treatment with iron sulfate, have limited time before birth, or have other illnesses that complicate the anemia. We demonstrated that the use of adjuvant rHuEPO with iron sulfate reduces the anemia time period and is innocuous to the fetus. METHOD An experimental longitudinal prospective study; 100 pregnant women in their third trimester were included. Group 1 (n=50) was set as control for prevalence of anemia and establish hematological maternal and fetal parameters at delivery for our population; 50 women diagnosed with iron deficiency anemia were randomly assigned to treatment groups. Group 2 (n=25) third trimester women with a hemoglobin of <11g/dL were treated with iron sulfate, 600mg administered orally daily for 4 weeks, evaluating the hematologic response for the mother weekly and for both mother and fetus at birth; Group 3 (n=25) women similar to group 2, treated in addition with adjuvant rHuEPO, 4000 units subcutaneously, three times a week, for 4 weeks evaluating the same parameters. RESULTS Group 2 and 3 showed a corrected anemia before delivery (mean 11.1 vs 11.4g/dL), but Group 3 showed a statistically broader and more rapid increase in hemoglobin (1.22 vs 1.92g/dL, p value 0.013) with an rHuEPO dose of 4000 units, three times a week for 1 month. No clinical or hematologic difference or changes in growth were observed in the fetus. CONCLUSIONS Erythropoietin is safe and effective for both mother and fetus, although an ideal pregnancy dose has not yet been established.

Diaphragmatic hernia into the pericardium: case report

Diaphragmatic hernias are well described, differentiating between the most common posterolateral (Bochdalek), and the rarer central, right anterior (Morgagni), and left anterior (Larrey) hernias. These are primarily associated to congenital malformations in newborn, and in adults as undiagnosed congenital malformations or traumatic hernias. These may be present with herniation of liver, spleen, stomach, small intestine, colon, and omentum.

Anatomical variations of the ethmoidal roof: differences between men and women

AimDuring the paranasal sinuses surgery different complications may occur, both vascular and bony. The objective of the present study was to evaluate the ethmoidal roof configuration through the Keros and Yenigun classifications, analyzing results stratified by gender and side.Materials and methodsWe retrospectively analyzed 120 high-resolution computed tomography paranasal sinus study images and measured the depth of the cribriform plate in a coronal view and the anterior–posterior length in a cross section.ResultsThe Keros Type II was the most frequent and no statistically significant difference was found when comparing by gender. Yenigun type I was more prevalent, and a statistically significant difference was found between men and women in types I and II (p = 0.010 and p = 0.049, respectively). Statistical difference was observed in anterior–posterior means in the comparison between both classifications. In both, right and left side for men (p = 0.003 and p = 0.05) and women (p = 0.029 and p = 0.039).ConclusionWe demonstrate the morphological variability that exists in this region. Gender differences that must be considered by the surgeon to avoid complications. Further studies are needed to evaluate the value of these findings when predicting surgical complications. A CT before PNS surgery is already widely accepted.

Comments on: Implications of structural variations in the human sacrum: why is an anatomical classification crucial?

We sincerely appreciate the work done by Mahato [1] in which a qualitative classification of the sacrum is done to determine the number of segments, position of auricular surfaces, symmetry and abnormalities. This work is of the utmost importance since it is crucial for several surgical interventions and at the same time correlates certain pathologies with the morphology, mostly low back pain. It would be of great benefit having a quantitative study of the sacrum, like the one performed by our working group, Morales et al. [2], in which the morphometric characteristics (sacral foramina, pedicles, vertebral body and sacral canal) of 50 sacral specimens in Mexican population were obtained. With this information it is possible to determine the most prevalent characteristics that are present in the sacrum in Mexican population, which are critical for a safe intervention and compare them with the existing literature. In our work it was possible to establish that the pedicle length of S1 was longer than reported in previous studies. We recommend performing a similar study to the working group of Mahato, in which the morphometric characteristics of the sacral in Indian population are obtained, with this adding valuable information to the proposed classification in predicting the most prevalent measures. This would give a chance to have safer procedures after having done a clinical correlation of the pathology based on Mahato [1] and predict the sacrum measurements based on a similar study to ours, with this having correct screw placement and position in lumbosacral instrumentation, and also for other procedures that involves the sacral region as surgical and diagnostic target. The classification proposed by the working group of Mahato is of essential importance since it correlates the form and characteristics of the sacrum with the patient symptoms and gives valuable information to the surgeon that will perform a procedure. Besides, it presents information on the several variations present on the sacrum to be able to identify them. We consider it is important to take into account both analyses [1, 2].

Morphological Analysis of Bronchial Arteries and Variants with Computed Tomography Angiography

The aim of our study was to determine the prevalence of anatomical variants of bronchial arteries using computed tomographic angiography in a population of northeastern Mexico. An observational, transversal, descriptive, comparative, retrospective study was performed using 139 imaging studies of Mexican patients in which we evaluated the following parameters from the left and right bronchial arteries: artery origin, branching pattern, arterial ostium, vertebral level of origin, diameter, and mediastinal trajectory. The anatomies of the bronchial arteries were similar in both genders, except distribution for vertebral origin level (p  0.006) and the diameter (p  0.013). Left and right arteries were similar, except for the mediastinal trajectory in reference to the esophagus (p < 0.001) as well as the arterial diameter (p < 0.001) and lumen diameter.

Students helping students: Five years of experience

Peer teaching can be defined as the transmission of knowledge between colleagues from the same or similar stages of academic training. Near peer teaching (NPT) is a similar variant, in which higher level students (tutors typically 2–5 years ahead of the tutee in the academic program) mentor their junior classmates (tutees) by temporarily assuming the role of the instructor. This method has been utilized in many university and medical school settings (Evans and Cuffe, 2009; Jackson and Evans, 2012; Cantwell et al., 2015; Riddell and King, 2016). In the United Kingdom, the General Medical Council’s guidelines, Tomorrow’s Doctors: Recommendations on Undergraduate Medical Education, states that a medical graduate must “function effectively as a mentor and teacher” (GMC, 2009). Therefore, implementing an NPT program within an undergraduate curriculum stands to prepare medical students for their future role as educators. We have read with great interest the recent article published in ASE by Bruno et al. (2016), and we applaud their work; however, as the authors mentioned, there were several limitations. We agree that the sample size and the number of sessions involved were too small to draw any longstanding conclusions. We would like to bring to attention another important limitation. With regards to the analysis of student perceptions regarding the program, the authors based their findings on comments from the majority of students (74.3%) who attended a single session of the peer teaching program in human anatomy (Bruno et al., 2016). In our opinion, every student must complete at least 80% of the course in order to have a valid perception of the entire program. Five years ago we designed and implemented a human anatomy course in our medical school at Autonomous University of Nuevo Leon in Monterrey, Mexico, integrating NPT. We were faced with several obstacles: curriculum reform, an increase in student enrollment, low faculty-to-student ratios, and an insufficient number of cadavers for gross anatomy laboratory practical sessions. The course was reformatted to last 18 weeks and was divided into four learning modules: theory, clinical hours, anatomy imaging, and laboratory modules (Dur an et al., 2012). The theory module consisted of lectures that lasted one hour daily, five days a week, and were carried out in a traditional manner (one professor with 50 students). The laboratory section (three hours per week) was based on clinical reasoning activities guided by near-peer instructors who were previously trained by professors with regards to the subject matter (Dur an et al., 2012). When we first implemented this program in 2011, a total of 700 first-year students were enrolled in the human anatomy course. At the end of the semester more than 500 had agreed to answer a survey we designed to collect and analyze their opinions on the course design. We analysed qualitative aspects of the NPT program (i.e., communication skills, motivation, and performance) and found that the majority of students rated all of these aspects as eight or higher on a ten-point Likert scale. The mean student perception score regarding the course was 9.21. This survey is now applied at the end of each semester and thus far, all of the results have been satisfactory. In 2014, we began applying a survey to 120 near peer-teachers that were involved as instructors in our human anatomy course in order to obtain their views regarding their roles in the NPT program. Overall, instructors perceived that their participation benefited both themselves and the tutees. Most instructors agreed that they felt comfortable in their role and believed that all medical students should learn how to teach through NPT, or a similar program (Reyes-Hern andez et al., 2015). In our five years of experience, we have analyzed the responses from over 5,000 students and more than 200 near peer teachers, with a generally positive perspective regarding our program. Our method is constantly evolving and adapting to the new challenges we have faced each year. We have developed a monitoring system for training sessions and tutors, and we apply specific rubrics to evaluate the NPT implementation process, among other quality rubrics. In conclusion, we are certain NPT is a useful and dynamic method for teaching human anatomy in which both tutors and tutees are benefited. It is important to develop tools to assess the implementation of the teaching method, to ensure quality and satisfaction, while achieving the goals of the course.