Fracturas vertebrales causadas por reductores de velocidad o "lomos de burro" / Spinal fractures caused by speed bumps

Objetivo: Presentar una serie de casos de fracturas vertebrales en pasajeros de autobús asociadas al pasaje por reductores de velocidad. Materiales y métodos: Se realizó un estudio descriptivo y retrospectivo de una serie de casos de lesiones vertebrales torácicas y lumbosacras sufridas por pasajeros a causa del impacto del vehículo con reductores de velocidad. Se incluyó a pacientes tratados en dos instituciones, entre el 1 de enero de 2012 y el 1 de enero de 2023. Resultados: Se registraron 23 pacientes con lesiones vertebrales de la columna toraco-lumbosacra, 14 mujeres (60,9%) y 9 hombres (39,1%), promedio de la edad 43 años (DE ± 12; rango 25-62). Casi todos eran pasajeros (n = 22; 95,7%) que viajaban sentados en la última fila del autobús (n = 20; 86,5%). Un solo caso correspondía a un conductor del vehículo. Se documentaron 29 lesiones vertebrales, 28 fracturas toracolumbares (de T10 a L2; 96,6%) y una fractura de coxis (3,4%). La vértebra más comprometida fue L1 (n = 16; 55%). Las fracturas más graves (A3/A4) se asociaron con tratamiento quirúrgico (p = 0,007) y una mayor mediana de días de internación (p = 0,005). Conclusiones: Las lesiones vertebrales asociadas al impacto vehicular con reductores de velocidad son fracturas causadas por un mecanismo de compresión axial, más frecuentes en pasajeros ubicados en la última fila de asientos del autobús. Comprometen predominantemente la charnela toracolumbar y la vértebra fracturada con más frecuencia es L1 y exclusivamente uno de los platillos vertebrales. Nivel de Evidencia: IV

Objective: To present a case series of spinal fractures in bus passengers caused by passing over speed bumps. materials and methods: A descriptive and retrospective study of a case series of thoracic and lumbosacral spinal injuries suffered by passengers as a result of vehicle impacts with speed bumps was conducted. Patients treated at two institutions from January 1, 2012 to January 1, 2023 were included. Results: 23 patients with vertebral injuries of the thoracolumbosacral spine were recorded: 14 women (60.9%) and 9 men (39.1%), average age 43 years (SD±12; range=25-62). Almost all of the patients were passengers (n=22, 95.7%) sitting in the last row of seats on the bus (n=20, 86.5%). A single case was documented involving the vehicle's driver. 29 spinal injuries were recorded, 28 thoracolumbar fractures (from T10 to L2; 96.6%) and 1 coccyx fracture (3.4%). The most frequently involved vertebra was L1 (n=16; 55%). The most severe fractures (A3/A4) were associated with surgical treatment (p=0.007) and a longer median hospital stay (p=0.005). Conclusions: Spinal injuries during vehicular impact with speed bumps are caused by an axial compression mechanism, with greater involvement of passengers who are located in the last row of seats. They primarily affect the thoracolumbar joint, with the L1 vertebra and exclusively one of the vertebral endplates being fractured most frequently. Level of Evidence: IV

Innervation of the heart: Anatomical study with application to better understanding pathologies of the cardiac autonomics.

Current advances in management of the cardiac neuroaxis in different cardiovascular diseases require a deeper knowledge of cardiac neuroanatomy. The aim of the study was to increase knowledge of the human fetal extrinsic cardiac nervous system. We achieved this by systematizing the origin and formation of the cardiac nerves, branches, and ganglia and their sympathetic/parasympathetic connections. Thirty human fetuses (60 sides) were subjected to detailed sub-macroscopic dissection of the cervical and thoracic regions. Cardiac accessory ganglia lying on a cardiac nerve or in conjunction with two or more (up to four) nerves before entering the mediastinal cardiac plexus were observed in 13 sides. Except for the superior cardiac nerve, the sympathetic cardiac nerves were individually variable and inconstant. In contrast, the cardiac branches of the vagus nerve appeared grossly more constant and invariable, although the individual cardiac branches varied in number and position of origin. Each cervical cardiac nerve or cardiac branch of the vagus nerve could be singular or multiple (up to six) and originated from the sympathetic trunk or the vagus nerve by one, two, or three roots. Sympathetic nerves arose from the cervical-thoracic ganglia or the interganglionic segment of the sympathetic trunk. Connections were found outside the cardiac plexus. Some cardiac nerves were connected to non-cardiac nerves, while others were connected to each other. Common sympathetic/parasympathetic cardiac nerve trunks were more frequent on right (70%) versus left sides (20%). The origin, frequency, and connections of the cardiac nerves and branches are highly variable in the fetus. Detailed knowledge of the normal neuroanatomy of the heart could be useful during cardiac neuromodulation procedures and in better understanding nervous pathologies of the heart.

Coronary anatomy of Commerson's dolphin (Cephalorhynchus commersonii) / Anatomia coronaria de la tonina overa (Cephalorhynchus commersonii)

The Commerson's dolphin (Cephalorhynchus commersonii) is an odontocete cetacean specie that lies in the waters of the southern hemisphere. With the aim of studying the course and distribution of Cephalorhynchus commersonii's coronary arteries, an exhaustive heart dissection was performed on one specimen. To the extent of our knowledge, and basing upon an extensive bibliographic research on the commersonii species, this is the first reported description of a Commerson's dolphin heart anatomy. Despite the fact that the analysis of a unique specimen does not allow to establish final conclusions, comparisons reveal broad similarities between Cephalorhynchus commersonii's coronary distribution and previous anatomical studies describing the heart of various marine diving mammals and the human fetus circulation. Diving mammals have developed an anastomotic system along evolution, in order to adjust their bodies to diving imposed conditions, and minimize the oxygen demand of the heart muscle. The present work begins with the identification of the patterns and similarities between Commerson's dolphin heart anatomy when compared to other odontecete species, to continue with an exhaustive description of the Commerson's dolphin coronary anatomy.

La tonina overa (Cephalorhynchus commersonii) es una especie de cetáceo odontoceto que se encuentra en las aguas del hemisferio sur. Con el objetivo de estudiar el curso y la distribución de las arterias coronarias de Cephalorhynchus commersonii, se realizó una disección exhaustiva del corazón de un ejemplar. Hasta donde sabemos, y basándonos en una extensa investigación bibliográfica sobre la especie, esta es la primera descripción informada de la anatomía de un corazón de este ejemplar. A pesar de que el análisis de una sola muestra no permite establecer conclusiones finales, las comparaciones revelan amplias similitudes entre la distribución coronaria de Cephalorhynchus commersonii, los estudios anatómicos previos que describen el corazón de varios mamíferos marinos buceadores, y la circulación del feto humano. Los mamíferos buceadores han desarrollado un sistema anastomótico a lo largo de la evolución para ajustar sus cuerpos a las condiciones impuestas por el buceo y minimizar la demanda de oxígeno del músculo cardíaco. El presente trabajo comienza con la identificación de los patrones y similitudes entre la anatomía del corazón de tonina overa en comparación con otras especies odontecetas, continuando con una descripción exhaustiva de la anatomía coronaria.