Epidemiological profile of surgical treatment of varicose veins in Brazil from 2010 to 2020.

Background: Varicose veins have become more common over recent years and in the most serious cases surgical treatment is necessary to resolve patients' clinical status. Despite their importance, there are no epidemiological studies that cover the whole of Brazil, showing how surgery to correct varicose veins conducted by the Unified Health System (SUS) is distributed in the country. Objectives: To describe the ecological profile of surgical treatment to correct varicose veins in Brazil from 2010 to 2020. Methods: This is a descriptive-analytical study of data obtained from the SUS Hospital Information System. These data were tabulated and categorized by state, region, type of procedure, and year. BioEstat 5.3 was used to conduct chi-square statistical tests with a 95% confidence interval and significance cutoff of p <0.05. Results: From 2010 to 2020, 755,752 surgical operations to treat varicose veins were conducted; 292,538 were unilateral (38.71%) and 463,214 (61.29%) were bilateral. Of these, 418,791 (55.41%) procedures were performed in the Southeast region, followed by 180,689 (23.91%) in the South region. A total of 40 deaths were registered in connection with these procedures during the period, 26 of which (65%) were associated with bilateral surgery and the majority of which occurred in the Southeast (24 deaths). Conclusions: It was observed that the majority of procedures are performed in the Southeast and South regions, and that bilateral elective surgery is the most prevalent.

Novel Porcine Kidney-Based Microsurgery Training Model for Developing Basic to Advanced Microsurgical Skills.

BACKGROUND: Microsurgery training is critical to the practice of microvascular procedures in many surgical areas. However, even simple procedures require different levels of complex skills. Therefore, simulation-based surgical training, mainly in the area of vascular anastomosis, is of great importance. In this paper, we present a new microsurgery training model for the development of basic to advanced microsurgical skills. METHODS: Porcine kidneys were purchased from a legal butchery slaughterhouse. First, kidneys were washed with water to remove blood and clots inside vessels. Then, dissection was performed throughout the vascular pedicle from the renal arteries to the segmentary branches. Finally, the longitudinal sectioning of the kidney parenchyma was performed to expose the vessels necessary for training. Sixty end-to-end anastomoses were performed. Specific instruments and materials were used to perform anastomoses and dissections with magnification by a video system. We evaluated the diameter of vessels, time to perform anastomosis, and patency of anastomosis. RESULTS: There was no great anatomical variation among the porcine kidneys. The total length for dissection training was 25.80 ± 7.44 cm using the arterial and venous vessel. The average time to perform arterial anastomoses was 23.79 ± 4.55 minutes. For vessel diameters of ≤ 3, 4 to 6, and 7 to 10 mm, the average procedure times were 27.68 ± 3.39, 22.92 ± 4.12, and 20.77 ± 3.44 minutes, respectively. Regarding venous anastomosis, the average duration of the procedure was 26.17 ± 4.80 minutes, including durations of 31.61 ± 3.86, 25.66 ± 4.19, and 21.24 ± 3.79 minutes for vessel diameters of ≤ 7, 8 to 10, and >10 mm, respectively. Positive patency was achieved in all surgeries. CONCLUSION: The porcine kidney provides an inexpensive and convenient biological model for modeling microanastomosis with high fidelity to vascular structures.

Vascular surgery in the most populous state in the Amazon: socio-professional profile and aspirations of the specialty.

BACKGROUND: There is a dearth of studies conducted to understand the socio-professional profile of the vascular surgery specialty and the population demands of specific regions, which are needed to support creation of care policies and direct infrastructure improvements in healthcare. OBJECTIVES: The purpose of this study was to describe the socio-professional profile of vascular surgeons in the state of Pará, Brazil, to guide creation of tools for professional improvement. METHODS: A cross-sectional, self-report survey was conducted in Pará using a questionnaire comprising 30 questions covering six main topics. RESULTS: All vascular surgeons actively practicing in the state participated in this study. The total number of specialists was 59, with 71.2% working in the greater Belém area and 16.9% exclusively practicing in the interior of the state. The mean age of these professionals was 48 ± 11.1 years, 86.4% of respondents were men, 64.4% of surgeons had completed medical residency, and 96.6% (n=57) of the surgeons would like to improve their skills in venous surgery, echo-guided vascular access, and endovascular surgery. The method of professional improvement of greatest interest was simulation courses (hands-on), endorsed by 93% of the participants. CONCLUSIONS: Pará has 59 vascular surgeons. These professionals mainly work in the greater Belém (71.2%), in hospitals (100%) or in private clinics or offices (94.9%), performing a wide range of procedures, including venous and arterial surgery, amputations, and provision of hemodialysis access. More than 90% of these surgeons were satisfied professionally and reported that they would choose the specialty again. However, 22% had a pessimistic view of the specialty's future. The vast majority of professionals (96.6%) consider that training or a continuing education program are necessary.

CONTEXTO: Há uma falta de estudos necessários para entender o perfil socioprofissional da especialidade e as demandas específicas da população de uma região específica, a fim de subsidiar a criação de políticas assistenciais e a melhoria na infraestrutura da assistência à saúde. OBJETIVOS: O objetivo deste estudo foi descrever o perfil socioprofissional de cirurgiões vasculares no Pará para orientar a criação de ferramentas de melhoria profissional. MÉTODOS: Foi realizado um levantamento transversal no Pará utilizando um questionário com 30 questões que envolvia seis temas principais. RESULTADOS: Todos os cirurgiões vasculares ativos participaram deste estudo. O número total de especialistas foi de 59, dos quais 71,2% trabalhavam na grande Belém e 16,9% exclusivamente no interior do estado. A idade média dos profissionais foi de 48 ± 11,1 anos, e 86,4% dos entrevistados eram homens. Além disso, 64,4% dos cirurgiões haviam completado a residência médica, e 96,6% (n = 57) deles gostariam de ter melhorias em cirurgia venosa, acesso vascular ecoguiado e cirurgia endovascular. As áreas de maior interesse para melhorias são cursos de simulação (práticos), com 93% dos participantes interessados. CONCLUSÕES: O Pará tem 59 cirurgiões vasculares, os quais trabalham principalmente na grande Belém (71,2%) em hospitais (100%) ou em clínicas privadas ou consultórios (94,9%) e realizam uma ampla gama de procedimentos, incluindo cirurgias venosas e arteriais, amputações e acessos para hemodiálise. Mais de 90% dos cirurgiões estavam satisfeitos e relataram que escolheriam a especialidade novamente; entretanto, 22% tinham uma visão pessimista do futuro da especialidade. A grande maioria dos profissionais (96,6%) considera a necessidade de qualificação ou de um programa de educação continuada.

Betulinic Acid Prevents the Acquisition of Ciprofloxacin-Mediated Mutagenesis in Staphylococcus aureus.

The occurrence of damage on bacterial DNA (mediated by antibiotics, for example) is intimately associated with the activation of the SOS system. This pathway is related to the development of mutations that might result in the acquisition and spread of resistance and virulence factors. The inhibition of the SOS response has been highlighted as an emerging resource, in order to reduce the emergence of drug resistance and tolerance. Herein, we evaluated the ability of betulinic acid (BA), a plant-derived triterpenoid, to reduce the activation of the SOS response and its associated phenotypic alterations, induced by ciprofloxacin in Staphylococcus aureus. BA did not show antimicrobial activity against S. aureus (MIC > 5000 µg/mL), however, it (at 100 and 200 µg/mL) was able to reduce the expression of recA induced by ciprofloxacin. This effect was accompanied by an enhancement of the ciprofloxacin antimicrobial action and reduction of S. aureus cell volume (as seen by flow cytometry and fluorescence microscopy). BA could also increase the hyperpolarization of the S. aureus membrane, related to the ciprofloxacin action. Furthermore, BA inhibited the progress of tolerance and the mutagenesis induced by this drug. Taken together, these findings indicate that the betulinic acid is a promising lead molecule in the development helper drugs. These compounds may be able to reduce the S. aureus mutagenicity associated with antibiotic therapies.

Portable model for vasectomy reversal training.

OBJECTIVES: to validate an experimental non-animal model for training of vasectomy reversal. MATERIALS AND METHODS: The model consisted of two artificial vas deferens, made with silicon tubes, covered by a white resin, measuring 10 cm (length) and internal and external diameters of 0.5 and 1.5 mm, respectively. The holder of the ducts is made by a small box developed with polylactic acid, using a 3D print. The objective of the invention is to simulate the surgical field of vasovasostomy, when the vas deferens are isolated from other cord structures. For validation, it was verified the acquisition of microsurgical skills during its use, in a capacitation course with 5 urology residents from a Hospital of the region. Along the training sessions, it was analyzed the time (speed) of microsurgical sutures, and quantification of the performance using a checklist. Collected data were analyzed using de BioEstat®5.4 software. RESULTS: Medium time for the completion of microsurgical sutures improved considerably during the course, and reached a plateau after the third day of training (p=0.0365). In relation to the checklist, it was verified that during capacitation, there was significant improvement of the scores of each participant, that reached a plateau after the fourth day of training with the model (p=0.0035). CONCLUSION: The developed model was able to allow the students that attended the course to gain skills in microsurgery, being considered appropriate for training vasectomy reversal.

The Evaluation of Medication Adherence in Patients Infected With HCV Receiving Protease Inhibitors: A Pilot Study.

Adherence to treatment is essential for hepatitis C cure. Studies show the complexity of the treatment due to side effects, many pills, and rigor in the schedules. The aim of this study was to evaluate the adherence to treatment with protease inhibitor in patients with hepatitis C. It is a longitudinal, observational, prospective pilot study with patients with hepatitis C genotype 1. Bimonthly consultations and biweekly calls for 20 weeks were performed. Evaluation methods for adherence were Measure of Adherence to Treatment score, patient report, count pills, and sustained virological response. Twenty-two patients were enrolled. Mean age was 54.0 ± 8.72 years; 50% were men, educational level was 7.9 ± 3.89 years for the study, and intake of pills was 2.2 ± 1.60 per day. Adverse events reported were fatigue (90.9%), muscular pain (72.7%), and nausea (68.2%). In total, 71.4% of patients took 100% of medications and were classified as having a high degree of adherence to treatment. The sustained virological response was not significant in relation to the high or low adherence degree. Measure of Adherence to Treatment score is a good instrument to measure adherence to protease inhibitor treatment. The adherence of patients undergoing long-term and complex treatments improves when the multidisciplinary team follows up every 7-15 days. The patient's access to the team through additional phone calls or medical/nursing appointment is essential to improve adherence.

Sorafenib for Advanced Hepatocellular Carcinoma: A Real-Life Experience.

INTRODUCTION: Sorafenib (SOR) has proved to be effective in patients with advanced hepatocellular carcinoma (HCC), since overall survival was higher in phase III clinical trials; however, disease progression can occur. OBJECTIVES: The study aimed to describe real-life experience in advanced HCC treatment with SOR at a university hospital in Brazil and to estimate the number of patients with indication of second-line therapy. METHODS: This is a retrospective study that included cases of HCC with prescription of SOR based on real-life practice between 2011 and 2016. Demographic, clinical, and laboratory data were collected. RESULTS: From 572 patients with HCC, SOR was prescribed in 103 cases. From them, 62.1% were classified as Child-Pugh (CP)-A, 54.4% as Barcelona Clinic Liver Cancer (BCLC)-C, and 74 (71.8%) started treatment. Overall survival was 25.5 (95% CI 17.0-34.1) months and 1-year survival was greater in patients who received SOR than in non-treated (88.7 vs. 44.4%, p < 0.001). There was no difference in survival between BCLC-B and C (p = 0.405), as well as CP-A and B (p = 0.919). In 21.6% of the patients, a second-line therapy with regorafenib was indicated. CONCLUSION: In this real-life study, SOR significantly increased the survival rate by 1 year in patients with advanced HCC regardless of BCLC staging and CP score. Second-line therapy would be indicated in 21.6% of cases.

ST8Sia2 polysialyltransferase protects against infection by Trypanosoma cruzi.

Glycosylation is one of the most structurally and functionally diverse co- and post-translational modifications in a cell. Addition and removal of glycans, especially to proteins and lipids, characterize this process which has important implications in several biological processes. In mammals, the repeated enzymatic addition of a sialic acid unit to underlying sialic acids (Sia) by polysialyltransferases, including ST8Sia2, leads to the formation of a sugar polymer called polysialic acid (polySia). The functional relevance of polySia has been extensively demonstrated in the nervous system. However, the role of polysialylation in infection is still poorly explored. Previous reports have shown that Trypanosoma cruzi (T. cruzi), a flagellated parasite that causes Chagas disease (CD), changes host sialylation of glycoproteins. To understand the role of host polySia during T. cruzi infection, we used a combination of in silico and experimental tools. We observed that T. cruzi reduces both the expression of the ST8Sia2 and the polysialylation of target substrates. We also found that chemical and genetic inhibition of host ST8Sia2 increased the parasite load in mammalian cells. We found that modulating host polysialylation may induce oxidative stress, creating a microenvironment that favors T. cruzi survival and infection. These findings suggest a novel approach to interfere with parasite infections through modulation of host polysialylation.

Low-cost suture simulator to gain basic surgical skills.

PURPOSE: To introduce a new low-cost simulation model for training basic surgical skills. METHODS: The training model was made from a mixture of 20 g of acetic silicone with 11 g of maize starch. Validation consisted of serial training sessions, evaluating the mean pre- and post-training time and the mean final score according to the global rating scale. RESULTS: A decrease in the time required to perform the sutures was observed, comparing the average post and pre-training time of each training day, with a significant correlation between the order of training and the time for performing the simulation. CONCLUSIONS: The presented model proved to be capable of simulating the basic suture training skills. It is easy to make, has low cost, and can be easily reproduced in educational institutions.

Women in surgery: do surgical specialties keep up with the feminization of medicine in Brazil?

INTRODUCTION: historically, surgical medical specialties are mostly male, a scenario which, in recent years, has undergone changes. In this sense, despite the relevance of the growth of female participation in the medical career, little is discussed about the distribution between genders of the main surgical medical specialties in the country. OBJECTIVE: discuss the process of feminization in surgical specialties in Brazil over the last few years, tracing a distribution profile of these specialties. METHODS: this is a retrospective and cross-sectional study with secondary data from the Censuses of Medical Demography in Brazil in the years 2011, 2013, 2015, 2018, 2020 and 2023, including the surgical specialties: Urology, Orthopedics and Traumatology, Thoracic Surgery, Neurosurgery, Digestive System Surgery, Cardiovascular Surgery, Hand Surgery, General Surgery, Head and Neck Surgery, Vascular Surgery, Plastic Surgery, Ophthalmology, Coloproctology, Otorhinolaryngology, Pediatric Surgery, and Gynecology and Obstetrics. RESULTS: males prevails in numbers, among the surgical specialties, however, with a lower growth rate compared to females. Specialties such as urology, orthopedics and traumatology and neurosurgery are mostly male, while gynecology and obstetrics are female. CONCLUSION: it is evident that female participation in the surgical medical field has increased significantly over the last few years.

Profile of thyroidectomies in Brazil from 2010 to 2020 from a macro-regional perspective.

Objective: To describe the distribution profile of thyroidectomies in Brazil from 2010 to 2020 from a macro-regional perspective. Materials and methods: This is a retrospective, detailed and descriptive study built on secondary data obtained from the Hospital Information System of the Unified Health System (SIH/SUS). We organized the data in tables and grouped them according to the federative unit, macro-region, type of procedure, mortality rate, and year of performance. We performed statistical analysis using the χ2 test to assess the association between the variables, observing a P value of < 0.05 and a confidence interval of 95%. Results: From 2010 to 2020, 160 219 thyroidectomy surgeries were performed, of which 77 812 (48.56%) were total, 38 064 (23.76%) partial and 41 191 (25.70%) oncological. The Southeast was responsible for the largest share of procedures, with 70 745 (44.15%), followed by the Northeast with 43 887 (27.39%). In 2020, the procedure was less performed, with 9226 (5.75%) surgeries. The total mortality rate was 0.16% during the study period. Conclusion: We found that thyroidectomies are carried out mainly in the Southeastern, Northeastern, and Southern regions, and showed a downward trend in 2020, which may be related to the COVID-19 pandemic. In addition, total thyroidectomy is the most performed surgery, and the Northern region had the highest mortality rate.

Low cost and easy acquisition: corn grain in microsurgery training.

OBJECTIVES: develop an easily accessible model for training the initial motor practice in microsurgery using corn kernels. METHODS: ten corn kernels (Zea mays) were used. A 7mm longitudinal cut was made on one side of the corn grain. The training consisted of performing 4 simple knots between the edges of the incision, using 10-0 mononylon thread. The parameters analyzed were 1) cost of the model; 2) assembly time of the model test system; 3) time for performing the knots; 4) distance between the knots. RESULTS: in all corn kernels tested, it was possible to perform the proposed microsurgical suture training, without any difficulty in the procedure. The average time to perform the 4 knots was 6.51±1.18 minutes. The total cost of the simulator model was R$3.59. The average distance between the knots was 1.7±0.3mm. The model developed from corn grains has an extremely low cost when compared to the use of animals or high-tech simulators. Other advantages are the easy availability of canned corn kernels and the possibility of making more than four knots along the 7mm incision. CONCLUSION: the training model developed has low cost, is easy to acquire and viable for training basic manual skills in microsurgery.

The Effects of Hydrolyzed Collagen and Collagen Peptide in the Treatment of Superficial Chondral Lesions: An Experimental Study.

Objective To evaluate the effects of hydrolyzed collagen and collagen peptide in the treatment of superficial chondral lesions in rats. Method This research employed 18 Rattus norvegicus . A single intraarticular infiltration of sodium iodoacetate (2 mg solution) through the patellar ligament induced joint damage in previously anesthetized animals. We divided the animals into three groups: a control group, a collagen peptide group, and a hydrolyzed collagen group. Treatment consisted of oral administration of collagen peptide or hydrolyzed collagen for 30 days. Afterwards, we euthanized the animals and studied the joint chondral changes. We evaluated the results according to the chondrocyte clusters count and a histological evaluation, as per Pritzker et al. Results There was no statistical significance in injury stages between the control, hydrolyzed collagen, and collagen peptide groups ( p = 0.11). Regarding scores, there was a statistical significance between the groups treated with hydrolyzed collagen and collagen peptide ( p < 0.05), but not in comparison with the control group. Conclusion The proposed treatments of the induced chondral lesion with the oral administration of hydrolyzed collagen or collagen peptides were effective, resulting in lesion stabilization or regression, and warranting further experimental research to understand and improve the primary outcome of this study.

A realistic model for vasectomy reversal training using swine testicles.

PURPOSE: To evaluate the viability of the porcine vas deferens as a realistic microsurgical training model for vasectomy reversal. METHODS: The model uses swine testicles (vas deferent), which are usually discarded in large street markets since they are not part of Brazilian cuisine. The spermatic cord was carefully dissected, and the vas deferens were isolated, measuring 10 cm in length. A paper quadrilateral with 5 cm2 was built to delimit the surgical training field. The objective of the model is to simulate only the microsurgical step when the vas deferens are already isolated. The parameters analyzed were: feasibility for reproducing the technique, patency before and after performing the vasovasostomy, cost of the model, ease of acquisition, ease of handling, execution time, and model reproducibility. RESULTS: The simulator presented low cost. All models made were viable with a texture similar to human, with positive patency obtained in 100% of the procedures. The internal and external diameters of the vas deferens varied between 0.2-0.4 mm and 2-3 mm, respectively, with a mean length of 9 ± 1.2 cm. The total procedure time was 43.28 ± 3.22 minutes. CONCLUSIONS: The realistic model presented proved to be viable for carrying out vasectomy reversal training, due to its low cost, easy acquisition, and easy handling, and providing similar tissue characteristics to humans.

Anacardium occidentale L. (cajueiro) in the healing of skin wounds: an experimental study in rats.

PURPOSE: To analyze the effects of Anacardium occidentale Linn on the healing of skin wounds. METHODS: Twenty Wistar male rats were distributed into four groups (with five animals each one): negative control group (NCG), treated with saline solution; cashew tree group (CG), treated with hydroalcoholic extract of the bark of A. occidentale Linn; manipulated cashew tree group (MCG), with the ointment of extract of the bark of A. occidentale Linn; positive control group (PCG), treated with sunflower oil. All animals were examined daily, observing the macroscopic aspects of the surgical wound. Hematoxylin-eosin staining was used for tissue morphology analysis and Masson's trichrome for better collagen fiber characterization. RESULTS: On day 7, the MCG group had the expansion of the surgical wound covered by crust, exceeding the initial limits. On day 21, the wounds were observed to be completely closed and epithelialized in the NCG and CG groups. PCG and MCG still had remnants of crusts on the wound. The NCG was the only one not to present an abscess in histopathological analysis. CONCLUSIONS: There was a prolongation of the healing phase of the animals treated with the extract, and the animals in the NCG showed a better outcome by histological analysis.

Protein Arginylation Is Regulated during SARS-CoV-2 Infection.

BACKGROUND: In 2019, the world witnessed the onset of an unprecedented pandemic. By February 2022, the infection by SARS-CoV-2 has already been responsible for the death of more than 5 million people worldwide. Recently, we and other groups discovered that SARS-CoV-2 infection induces ER stress and activation of the unfolded protein response (UPR) pathway. Degradation of misfolded/unfolded proteins is an essential element of proteostasis and occurs mainly in lysosomes or proteasomes. The N-terminal arginylation of proteins is characterized as an inducer of ubiquitination and proteasomal degradation by the N-degron pathway. RESULTS: The role of protein arginylation during SARS-CoV-2 infection was elucidated. Protein arginylation was studied in Vero CCL-81, macrophage-like THP1, and Calu-3 cells infected at different times. A reanalysis of in vivo and in vitro public omics data combined with immunoblotting was performed to measure levels of arginyl-tRNA-protein transferase (ATE1) and its substrates. Dysregulation of the N-degron pathway was specifically identified during coronavirus infections compared to other respiratory viruses. We demonstrated that during SARS-CoV-2 infection, there is an increase in ATE1 expression in Calu-3 and Vero CCL-81 cells. On the other hand, infected macrophages showed no enzyme regulation. ATE1 and protein arginylation was variant-dependent, as shown using P1 and P2 viral variants and HEK 293T cells transfection with the spike protein and receptor-binding domains (RBD). In addition, we report that ATE1 inhibitors, tannic acid and merbromine (MER) reduce viral load. This finding was confirmed in ATE1-silenced cells. CONCLUSIONS: We demonstrate that ATE1 is increased during SARS-CoV-2 infection and its inhibition has potential therapeutic value.

Incisional hernia repair in rats: description of the sublay technique under videomagnification system.

PURPOSE: To describe the technique of sublay correction of incisional hernia in Wistar rats under videomagnification system. METHODS: Five male rats of the species Rattus norvegicus, of the Wistar lineage, with body weight between 250-350 g and 60 days old were used. Incisional hernia was inducted in all animals. After that, the incisional hernia was immediately corrected by the sublay method. RESULTS: There were no cases of recurrence of the incisional hernia after placement of the polypropylene mesh using the sublay technique. No postoperative complications were observed. CONCLUSIONS: The technique is suitable for execution in Wistar rats.

Anatomical description of the extratemporal facial nerve under high-definition system: a microsurgical study in rats.

PURPOSE: To describe the microsurgical anatomical aspects of the extratemporal facial nerve of Wistar rats under a high-definition video system. METHODS: Ten male Wistar rats (12-15 weeks old), without veterinary diseases, weighing 220-280 g, were used in this study. All animals in this study were submitted to the same protocol and by the same surgeon. A 10-mm incision was made below the bony prominence of the right or left ear, and extended towards the angle of the mandible. The dissection was performed and the main branches of the facial nerve were dissected. RESULTS: The main trunk of the facial nerve has a length of 0.88 ± 0.10 mm and a length of 3.81 ± 1.03 mm, measured from its emergence from the stylomastoid foramen to its bifurcation. Seven branches originating from the facial nerve were identified: posterior auricular, posterior cervical, cervical, mandibular, buccal, temporal, and zygomatic. CONCLUSIONS: The anatomy of the facial nerve is comparable to that of humans, with some variations. The most observed anatomical division was the distribution in posterior auricular, posterior cervical, cervical, mandibular, buccal, temporal, and zygomatic branches. There is no statistical difference between the thickness and distance of the structures compared to the contralateral side.

Anatomorphometry of the brachial plexus under high-definition system: an experimental study in rats.

PURPOSE: To study the anatomorphometry of the plexus brachialis (PB) of rats under a high-definition video system. METHODS: Ten male Wistar rats discarded from other research that did not interfere in the morphology of the animal, respecting the principle of reduction, were used. All animals were submitted to the same protocol. Initially, the cervical region was shaved. The animals were placed in a dorsal position. A single elbow-to-elbow incision was performed and dissection started at the deltopectoral sulcus. The procedures were performed under a video system. To measure the structures, the Image J software was used. RESULTS: All the PB evaluated originated from the C5-T1 spinal nerves. C5 and C6 converged to form the truncus superior, the root of C7 originated the truncus medius, and the confluence of C8 and T1 originated the truncus inferior. It was found the union of C7, C8, and T1 to form truncus inferomedialis instead of separate medial and inferior truncus. C8 (1.31 mm) was the thickest root, the truncus inferior (1.80 mm) and the nerve radialis (1.02 mm), were the thickest. CONCLUSIONS: The anatomy of the PB is comparable to humans, admitting variations. The videomagnification system is useful to perform microsurgical dissection.

Anatomical description of the ventral and dorsal cervical rootlets in rats: A microsurgical study.

PURPOSE: To describe the anatomical aspects of the cervical rootlets and to quantify the number of rootlets that compose C1 to T1. METHODS: Twenty male rats were used in this study. The dorsal rootlets from C1 to T1 were analyzed. To study the ventral rootlets, the posterior root avulsion was performed using a microhook, allowing exposure of the ventral roots through manipulation of the denticulate ligament and arachnoid mater. The parameters analyzed were the number of ventral and dorsal rootlets by side and level. RESULTS: The formation of the respective spinal nerve was observed in the spinal roots the union of the ventral and dorsal roots. In four animals the C1 spinal root had no dorsal and/or ventral contribution. There is no normal pattern of numerical normality of the dorsal and ventral rootlets. The average number of fascicles per root was 4.08, with a slight superiority on the left side. There was a slight superiority of the dorsal rootlets compared to the ventral rootlets. CONCLUSIONS: This investigation was the first to study cervical rootlets in rats. In 20% of the sample studied, the dorsal root of C1 was absent mainly on the left side. There is a nonlinear numerical increase from C1 to T1 in the rootlets. There is a numerical predominance of cervical fascicles on the left side, confronting several studies related to the functional predominance of right laterality, requiring new studies that correlate these variables.