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Background: The objective of this work was to perform a critical review of the 2-dimensional and 3-dimensional anatomy of the adult brachial plexus divisions and cords. Methods: Twelve adult brachial plexuses from fresh cadavers were dissected. All were male and aged between 30 and 50 years. Only corpses without brachial plexus injuries were selected. The purpose of the dissections was to identify the origin of the anterior and posterior divisions of the adult brachial plexus in their respective trunks, as well as the positioning of the posterior, lateral, and medial cords. Results: The posterior division of all trunks had a cranial and dorsal origin, while the anterior division of all trunks had a caudal and ventral origin. The posterior cord was the most cranial of all, the lateral cord was central, and the medial cord was the most caudal of all cords. The posterior division of the superior trunk was always between the suprascapular nerve and the anterior division. Conclusions: Brachial plexus diagrams in most textbooks and papers are different from what was found in our dissections. Contrary to the known diagram, the posterior divisions always had a cranial origin in the superior, middle, and inferior trunks.

Simulation platforms are increasingly becoming complementary tools for cutting-edge cardiovascular research. The interplay among structural properties of the arterial wall, morphometry, anatomy, wave propagation phenomena, and ultimately, cardiovascular diseases continues to be poorly understood. Accurate models are powerful tools to shed light on these open problems. We developed an anatomically detailed computational model of the arterial vasculature to conduct 1-D blood flow simulations to serve as simulation infrastructure to aid cardiovascular research. An average arterial vasculature of a man was outlined in 3-D space to serve as geometrical substrate for the mathematical model. The architecture of this model comprises almost every arterial vessel acknowledged in the medical/anatomical literature, with a resolution down to the luminal area of perforator arteries. Over 2000 arterial vessels compose the model. Anatomical, physiological, and mechanical considerations were employed for the set up of model parameters and to determine criteria for blood flow distribution. Computational fluid dynamics was used to simulate blood flow and wave propagation phenomena in such arterial network. A sensitivity analysis was developed to unveil the contributions of model parameters to the conformation of the pressure waveforms. In addition, parameters were modified to target model to a patient-specific scenario. On the light of the knowledge domain, we conclude that the present model features excellent descriptive and predictive capabilities in both patient-generic and patient-specific cases, presenting a new step toward integrating an unprecedented anatomical description, morphometric, and simulations data to help in understanding complex arterial blood flow phenomena and related cardiovascular diseases.

OBJETIVO: Comparar clínica e anatomicamente os limites do nervo fibular na zona de segurança de Gerdy em cadáveres. MÉTODOS: Foram utilizados 50 espécimes anatômicos de joelhos e medidos clinicamente (antes de dissecção) para determinar as distâncias e ângulos entre: o tubérculo de Gerdy e a região posterior da fíbula (cm), ângulo entre a linha correspondente à região posterior da fíbula e a crista tibial (graus) e o ângulo entre o tubérculo de Gerdy e crista tibial (graus). Após a dissecção das peças anatômicas, os joelhos foram novamente medidos, para determinar as distâncias e ângulos entre: o tubérculo de Gerdy e o nervo fibular (cm), ângulo entre o nervo fibular, na região posterior da fíbula e a crista tibial (graus) e o ângulo entre o tubérculo de Gerdy e crista tibial (graus). RESULTADOS: Existe aumento significativo da distância entre o tubérculo de Gerdy e a região posterior da fíbula (cm), após dissecção, em média 0,26cm (p = 0,018), o que corresponde a 8,6% (p = 0,007) e também existe diminuição significativa do ângulo entre a região posterior da fíbula e a crista tibial após dissecção, em média de 3º (p = 0,047), que corresponde a 2,1% (p = 0,06). CONCLUSÃO: Apesar da diferença antes e depois da dissecção, a zona de segurança de Gerdy pode ser considerada segura para os procedimentos ortopédicos, na região proximal da tíbia, evitando danos ao nervo fibular e seus ramos. OBJECTIVE: to clinically and anatomically compare the limits of the fibular nerve in Gerdy's Safe Zone in cadavers. METHODS: Fifty anatomical knee specimens were clinically measured (before dissection) to determine the distances and angles between: Gerdy's tubercle and the posterior region of fibula (cm); the angle between the line corresponding to the posterior region of fibula and the tibia crest (degrees); and the angle between Gerdy's tubercle and tibial crest (degrees). After dissection of the anatomical parts, the knees were measured again, to determine the distances and angles between: Gerdy's tubercle and the fibular nerve (cm), the angle between the fibular nerve, in the posterior region of the fibula, and the tibial crest (degrees), and the angle between Gerdy's tubercle and the tibial crest (degrees). RESULTS: There was a significant increase in the distance between Gerdy's tubercle and the posterior region of fibula (cm), after dissection, of an average 0.26 cm (p = 0.018), corresponding to 8.6% (p = 0.007). There was also a significant reduction in the angle between the posterior region of fibula and the tibial crest after dissection, of an average 3º (p = 0.047), corresponding to 2.1% (p = 0.06). CONCLUSION: Despite the difference before and after dissection, Gerdy's Safety Zone can be considered safe for orthopedic procedures involving the proximal region of the tibia, preventing damage to the fibular nerve and its branches.

OBJECTIVE: To establish the risk of lesion to the radial sensory nerve after percutaneous fixation in the distal radius region of cadavers. METHODS: The authors used 24 upper limbs of 12 skeletally mature cadavers, 10 male, and 2 female, mean age estimated as 50 years. A Kirschner wire was introduced in the styloid process of the radius to make the following determinations: distance between the wire and the radial sensory nerve, between the wire and the closest dorsal nerve branch, between the wire and the tendons of the first osteofibrous tunnel, and, finally, the number of branches of the radial sensory nerve. RESULTS: The site were the nerve appeared, between the two tendons and the Kirschner wire in the radial styloid process was a mean 5.09 cm, with a standard deviation of 0.75 cm. The distance between the Kirschner wire and the first dorsal branch was a mean 4.33 cm, ranging from zero to 10 cm. The number of nervous branches was a mean of four, ranging from two to eight branches. CONCLUSION: Results of this experimental study showed that when the wire is introduced in the styloid process of the radius, the risk of lesioning the radial sensory nerve is not a big risk. This risk is directly related to the number of nervous branches and to the angles of the wires while they are being introduced in the distal end of the radius.

Development of blood flow distribution criteria is a mandatory step toward developing computational models and numerical simulations of the systemic circulation. In the present work, we (i) present a systematic approach based on anatomical and physiological considerations to distribute the blood flow in a 1D anatomically detailed model of the arterial network and (ii) develop a numerical procedure to calibrate resistive parameters in terminal models in order to effectively satisfy such flow distribution. For the first goal, we merge data collected from the specialized medical literature with anatomical concepts such as vascular territories to determine blood flow supply to specific (encephalon, kidneys, etc.) and distributed (muscles, skin, etc.) organs. Overall, 28 entities representing the main specific organs are accounted for in the detailed description of the arterial topology that we use as model substrate. In turn, 116 vascular territories are considered as the basic blocks that compose the distributed organs throughout the whole body. For the second goal, Windkessel models are used to represent the peripheral beds, and the values of the resistive parameters are computed applying a Newton method to a parameter identification problem to guarantee the supply of the correct flow fraction to each terminal location according to the given criteria. Finally, it is shown that, by means of the criteria developed, and for a rather standard set of model parameters, the model predicts physiologically realistic pressure and flow waveforms. Fil: Blanco, Pablo Javier. Laboratorio Nacional de Computacao Cientifica; Brasil. National Institute of Science and Technology in Medicine Assisted by Scientific Computing, INCT-MACC; Brasil Fil: Watanabe, Sansuke M.. Laboratorio Nacional de Computacao Cientifica; Brasil. National Institute of Science and Technology in Medicine Assisted by Scientific Computing, INCT-MACC; Brasil. Federal Rural University of Pernambuco; Brasil Fil: Dari, Enzo Alberto. Comision Nacional de Energia Atomica. Gerencia de Area de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada. Grupo de Mecanica Computacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Passos, Marco Aurelio R.F.. Universidade Do Estado de Rio Do Janeiro; Brasil. Medical School of Petrópolis; Brasil Fil: Feijóo, Raúl A.. Laboratorio Nacional de Computacao Cientifica; Brasil. National Institute of Science and Technology in Medicine Assisted by Scientific Computing, INCT-MACC; Brasil