Angiographic description of the superior rectal artery and its anatomical variations in patients undergoing embolization of the superior rectal arteries in hemorrhoidal disease treatment.

BACKGROUND: Angiography of the superior rectal artery showed that its branches were divided into four main branches (two left and two right) in 46.8%; the second most frequent variation was one right and two left branches in 26.6%, followed by two branches to the right and one to the left in 20%; the most uncommon variations were one to the right and one to the left without further subdivision in 6.6%. BACKGROUND: ◼ The superior rectal artery, when it reaches the rectum, divides into two or more branches. BACKGROUND: ◼ Four patterns were observed in the angiographic anatomy of the superior rectal artery. BACKGROUND: ◼ Understanding the angiographic anatomy of the superior rectal artery is important to achieve optimal embolization results. OBJECTIVE: To describe angiographic findings of the superior rectal artery, its branches, and anatomical variations in the hemorrhoidal plexus in patients undergoing rectal artery embolization for hemorrhoidal disease treatment. METHODS: Angiographic findings of 15 patients were obtained from a single-center, prospective clinical study that compared superior rectal artery embolization with the Ferguson technique for hemorrhoidal disease between July 2018 and March 2020. RESULTS: Angiography of the superior rectal artery showed that in seven patients (46.8%), its branches were divided into four main branches (two left and two right), while in four patients (26.6%), the branches divided into one right and two left branches. The most uncommon variation observed in three cases (20%) was the branches divided into two branches to the right and one to the left; no further subdivision into the main branches was observed in one case (6.6%). CONCLUSION: Four patterns were observed in the angiographic anatomy of the superior rectal arteries. Knowledge of the angiographic anatomy of this region and its variations is essential to improve the effectiveness of superior rectal artery embolization. REGISTRY OF CLINICAL TRIALS: NCT03402282.

Prevalence of internal iliac artery anatomical variants in a Mexican population.

The internal iliac artery arises as a terminal extension of the common iliac artery and supplies blood to the pelvic region. This study aims to identify the anatomic variations of the internal iliac artery (IIA) in a Mexican population sample. This is a retrospective cross-sectional observational study. A total of 81 angiographies via the femoral artery approach performed on patients undergoing various medical procedures were included. Variations in the IIA branching patterns were identified by evaluating the angiographic images and grouped according to Adachi's classification into five types (I-V). A total of 139 hemipelvises were analyzed (78 right and 61 left). The frequencies of each type of variation were as follows: Type I (71.2%), Type II (10.79%), Type III (0 cases), Type IV (0.7%), Type V (12.94%), and unclassified (4.31%). The most frequent anatomical variants of the IIA in the western Mexican population sample were Type I, followed by Types V and II. Even though Type V is rare in most populations, it was the second most frequent variant in this study. Understanding the variants of the IIA branching pattern is necessary for performing invasive procedures in the pelvic region with precision and minimizing complications.

Muscularization of the chordae tendinea of the mitral anterior papillary muscle.

The chordae tendineae, described as fibro-collagenous structures, support the leaflets of the atrioventricular valves of the heart in various ways. The chordae tendineae are composed of collagen and elastic fibers. They connect to the ventricular side of the valve leaflets' free border and hinder the leaflets from swinging back into the atrial cavity during systole. Mitral valve chordae tendineae have been classified using a variety of classification systems. To our knowledge, we report a variant chordae tendinea that has yet to be described in the literature. The variant, present only on the mitral anterior papillary muscle, did not show the characteristic appearance of the chorda tendineae. Muscular fibers were observed extending from a larger than usual mitral anterior papillary muscle, inserting into the rough zone of the anterior leaflet. Several tendinous primary and secondary true leaflet chordae emerge from the apical portion of the anterior papillary muscle, inserting into the anterior leaflet's free edge and rough zone. Contraction of this muscular chorda during systole could disrupt the mechanics of valvular closure and result in possible regurgitation across the mitral valve. Additionally, this structure may be subject to rupture during myocardial infarction, leading to valvular dysfunction. The developmental connection between the chordae and papillary muscles could explain the anomalous muscularization of the chordae tendineae observed in this case.

Variations in Foramen Transversarium in Typical Cervical Vertebra / Variaciones del Foramen transverso en una Vértebra Cervical Típica

SUMMARY: In literature were described variations in foramen transversarium in cervical vertebrae, as well as their clinical importance, and the information about them boils down to the individual case reports or population morphological studies. The aim of this paper is to contribute to the knowledge of morphological characteristics of the transverse openings on vertebrae of the cervical region. The study was performed on 60 typical vertebrae that are part of the collection of the Department of Anatomy in Nis. The characteristics of permanent openings were measured and accessory foramina were recorded. It was found that the diameter of the openings on the left side was 5.595±0.92 x 5.390±1.507 mm, and on the right 5.766±1.201 x 6.101±1.401 mm. Unilateral completely separated accessory foramina were recorded in 10.17 % of cases, dominant on the left side, and incompletely separated cases in 5.09 %. The research has demonstrated a relatively high incidence of accessory foramina and deviations from circular shaped openings.

En la literatura se describen variaciones en el foramen transverso de las vértebras cervicales, así como su importancia clínica, y la información sobre ellas se reduce a informes de casos individuales o estudios morfológicos poblacionales. El objetivo de este trabajo fue contribuir al conocimiento de las características morfológicas de los forámenes transversos de las vértebras cervicales. El estudio se realizó en 60 vértebras típicas que forman parte de la colección del Departamento de Anatomía de Nis. Se midieron las características de los forámenes constantes y se registraron los forámenes accesorios. Se encontró que el diámetro de los forámenes del lado izquierdo era de 5,595±0,92 x 5,390±1,507 mm, y del derecho de 5,766±1,201 x 6,101±1,401 mm. Se registraron forámenes accesorios unilaterales completamente separados en el 10,17 % de los casos, dominantes en el lado izquierdo y casos incompletamente separados en el 5,09 %. La investigación ha demostrado una incidencia relativamente alta de forámenes accesorios y desviaciones de forma circular.

Complex Variations in Branches of the Axillary Artery / Variaciones Complejas en Ramas de la Arteria Axilar

SUMMARY: The axillary artery is a continuation of the subclavian artery and transitions into the brachial artery. Variations in the axillary artery are not uncommon. During the upper-limb dissection of a 95-year-old Korean female cadaver, assorted anatomical variations of the axillary artery branches were identified. On the right side, no branches emerged from the first part of the axillary artery. The thoracoacromial artery (excluding the pectoral branch) and the common subscapular trunk arose from the second part, with the common subscapular trunk giving origins to the pectoral branch, lateral thoracic artery, and subscapular artery. The subscapular artery is divided into the thoracodorsal artery, circumflex scapular artery, and accessory posterior circumflex humeral artery. Additionally, the superior thoracic artery arose from the lateral thoracic artery. The third part of the axillary artery gave rise to the anterior and posterior circumflex humeral arteries, accessory acromial branch, and accessory thoracodorsal artery. On the left side, the thoracoacromial artery (excluding the pectoral branch) and the superior thoracic artery arose from the first part. The common subscapular trunk arose from the second part, which included the pectoral branch, lateral thoracic artery, and subscapular artery. The subscapular artery is divided into the thoracodorsal artery, circumflex scapular artery, accessory posterior circumflex humeral artery, and accessory lateral thoracic artery. The third part gave rise to the anterior and posterior circumflex humeral arteries and the accessory acromial branch. This study presents variations of the axillary artery, emphasizing their rarity, considering their embryologic basis, and highlighting their importance not only for educational purposes but also surgical and radiological applications.

La arteria axilar es una continuación de la arteria subclavia y luego esta continua como arteria braquial. Las variaciones en la arteria axilar no son infrecuentes. Durante la disección de los miembros superiores de un cadáver de una mujer coreana de 95 años, se identificaron diversas variaciones anatómicas de las ramas de la arteria axilar. En el lado derecho no se originaban ramas de la primera parte de la arteria axilar. La arteria toracoacromial (excluyendo la rama pectoral) y el tronco subescapular común surgieron de la segunda parte, y el tronco subescapular común dio origen a la rama pectoral, la arteria torácica lateral y la arteria subescapular. La arteria subescapular se dividía en arteria toracodorsal, arteria circunfleja escapular y arteria humeral circunfleja posterior accesoria. Además, la arteria torácica superior se originaba de la arteria torácica lateral. La tercera parte de la arteria axilar dio origen a las arterias circunflejas humerales anterior y posterior, la rama acromial accesoria y la arteria toracodorsal accesoria. En el lado izquierdo, de la primera parte surgían la arteria toracoacromial (excluyendo la rama pectoral) y la arteria torácica superior. De la segunda parte se originaba el tronco subescapular común, que incluía la rama pectoral, la arteria torácica lateral y la arteria subescapular. La arteria subescapular se dividía en arteria toracodorsal, arteria circunfleja escapular, arteria circunfleja humeral posterior accesoria y arteria torácica lateral accesoria. La tercera parte daba origen a las arterias circunflejas humerales anterior y posterior y a la rama acromial accesoria. Este estudio presenta variaciones de la arteria axilar, enfatizando su rareza, considerando su base embriológica y destacando su importancia no sólo para fines educativos sino también para aplicaciones quirúrgicas y radiológicas.

Bifurcation of the mandibular canal according to sex, age, and facial skeletal pattern: a morphological and morphometric study of cone beam computed tomography.

PURPOSE: To assess the presence of mandibular canal bifurcation (BMC) and classify these variations by correlating findings with sex, age and facial skeletal pattern, measurements were made, including height, width, and distance from bifurcation to anatomical cortical bones. METHODS: BMC was identified in cone beam CT exams of 301 patients and classified according to its origin, location, direction, configuration and ending. The height and width of the MC before and after the bifurcation; height and width of the BMC; and distance from BMC to alveolar (C1), buccal (C2), lingual (C3) and basal (C4) bone cortices were measured. All data were correlated with sex, age, and facial skeletal pattern (class I, II, III). The significance level was 5%. RESULTS: 67 BMC (22.26%) were identified in 55 patients (18.28%). Bifurcations were more prevalent in females (p = 0.57), aged 18-39 years (p = 0.40), class I (p = 0.77). Single bifurcations, located in the posterior region of the mandible, originating in the MC, with a superior direction and ending in the retromolar foramen were more prevalent (p > 0.05). Mean cortical measurements were higher in male individuals, with significant differences only at C1 (p = 0.03). The mean height and width of BMC were 2.24 (± 0.62) and 1.75 (± 0.45) mm. There was no association between BMC classification and the variables studied (p > 0.05). CONCLUSION: Approximately 1/5 of the population studied had BMC. There were no associations of BMC presence or characteristics with sex, age, and facial skeletal pattern. The distance from bifurcation to alveolar (superior) cortical bone is greater in male individuals.

The anterior loop of the inferior alveolar nerve within the mentonian foramen: a scoping review.

PURPOSE: The aim of this study is to delineate the safety zone concerning the anteriorization of the AL and correlate it with the behavior of the AL, analyzing its feasibility. METHODS: Adhering to the Joanna Briggs Institute (JBI) manual guidelines, both the protocol and this review were conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) checklist. MeSH terms, combined with free terms, were utilized to search for articles in the following databases: Embase, LILACS, LIVIVO, PubMed/MEDLINE, Scopus, Web of Science, and grey literature. RESULTS: Fifteen articles were select following the eligibility criteria. An average safe zone of 4.75 mm in humans was observed, with a prevalence 60.8% and average anterior length of the AL of 2.09 mm in humans. CONCLUSION: The AL has varied patterns across different populations, then, it could not be asserted a 100% safe zone. Preoperative analysis of the AL with CBCT is always necessary. While it could be stated that a safe zone should be employed as an inviolable region, stipulated measures of a safe zone should be regarded as an area of greater attention in preoperative planning.

Unusually Pronounced and Expansive Mandibular Foramen. A Incidental Radiological Finding / Foramen Mandibular Inusualmente Pronunciado y Expansivo: Un Hallazgo Radiológico Incidental

SUMMARY: The mandibular foramen and its canal are one of the most important structures in the skull, as they solely supply the mandible through their associated nerves and vessels. Many anatomical variations have been reported in the literature until now, and this case report represents a clear-cut appearance of its shape in a panoramic radiograph, which is not mostly seen in normal panoramic radiographs. These factors are of utmost importance when it comes to performing various surgeries and preventing complications due to their varied anatomy, which will allow dentists to create a better treatment plan and provide better treatments without any complications.

El foramen mandibular y su canal son algunas de las estructuras más importantes del cráneo y cara, ya que a través de ellos la mandíbula es inervada por nervios e irrigada por vasos. Hasta ahora, en la literatura consultada, se han informado de numerosas variaciones anatómicas. En este trabajo reportamos la forma y trayecto del foramen y canal mandibular, obtenidos en una radiografía panorámica, que no es observada normalmente en este tipo de radiografía. Los factores anatómicos son de importancia a la hora de realizar las cirugías para prevenir complicaciones debido a su variada anatomía, permitiendo a los odontólogos crear un mejor plan de tratamiento sin ningún tipo de complicaciones.

Variaciones en el Origen de la Arteria Coronaria Derecha en Corazones de Avestruz (Struthio camelus) / Variations in the Origin of the Right Coronary Artery in Ostrich Hearts (Struthio camelus)

El avestruz (Struthio camelus) pertenece a un grupo de aves terrestres conocidas como ratites. La irrigación de su corazón presenta características muy similares a las de los mamíferos, con arterias distribuidas en la superficie cardíaca. La presencia de una sola arteria coronaria se considera una malformación congénita que podría provocar un déficit de perfusión coronaria y ser causa de sintomatología isquémica. Este estudio tiene como objetivo determinar las características morfológicas y anatómicas de las arterias coronarias en corazones de avestruz, con especial énfasis en la incidencia de malformaciones congénitas y su impacto clínico. Se analizaron 100 corazones de avestruz. Las aves tenían entre 12 a 15 meses de edad, con un peso promedio de 92 kg. Para una visualización precisa, se cateterizaron las arterias coronarias y se inyectó látex de neopreno 650 de Dupont, rojo para la arteria coronaria derecha y amarillo para la arteria coronaria izquierda. Los corazones se fijaron en formol al 10% durante 10 días. Se observaron dos casos en los que la arteria coronaria derecha se originaba como rama colateral de la arteria coronaria izquierda, uno discurría entre la aorta y la arteria pulmonar; el otro, anterior al tronco pulmonar, reemplazando a la arteria coronaria derecha. Las arterias coronarias tenían un diámetro de 3,2 mm y 2,5 mm, y se registró un trayecto de 90,4 mm y 123,4 mm, respectivamente, hasta llegar al margen derecho y la superficie diafragmática del corazón. Estas anomalías coronarias, aunque infrecuentes, pueden tener importantes implicaciones clínicas en avestruces debido a su alta velocidad al correr. La presencia de una arteria coronaria única puede aumentar el riesgo de compresión y, por ende, de isquemia. Estos hallazgos amplían el conocimiento sobre la anatomía coronaria del avestruz y subrayan la necesidad de más investigación para entender mejor sus implicaciones clínicas.

SUMMARY: The ostrich belongs to a group of terrestrial birds known as ratites. Their heart irrigation has characteristics very similar to those of mammals, with arteries distributed on the cardiac surface. The presence of a single coronary artery is considered a congenital malformation that could lead to a deficit in coronary perfusion and be a cause of ischemic symptomatology. We analyzed 100 ostrich hearts. Birds were aged between 12-15 months, with an average weight of 92 kg. For precise visualization, coronary arteries were catheterized and injected with Neoprene Latex 650 by Dupont, red for the right coronary artery, and yellow for the left coronary artery. They were fixed in 10 % formalin for 10 days. Two cases were observed where the right coronary artery originated as a collateral branch of the left coronary artery, one ran between the aorta and the pulmonary artery; the other anterior to the pulmonary trunk, replacing the coronary artery. Coronary arteries had a diameter of 3.2 mm and 2.5 mm; a 90.4 mm and 123.4 mm path was recorded reaching the right margin and diaphragmatic surface of the heart.

Morphology and Morphometry of the Dorsal Interosseous Muscles of the Hand: Laterality and Sexual Dimorphism / Morfología y Morfometría de los Músculos Interóseos Dorsales de la Mano: Lateralidad y Dimorfismo Sexual

SUMMARY: The dorsal interosseous muscles (DIM) are intrinsic muscles of the hand located dorsally between metacarpal bones, which play a role in finger abduction. Anatomical variations of these muscles in terms of form and length have been well documented, but variations regarding sex and laterality are underexplored. The aim of this study was to investigate the morphology and morphometry of the DIM of the hand regarding sexual dimorphism and laterality. Twenty human cadavers belonging to the white individuals (n = 40 hands) with known sex and laterality were used for this study. DIMs were dissected and observed for morphology. Also, a digital calliper was used to measure the midpoint length of the DIM. The origin and insertion of all the DIM were normal with the left hand having no additional, supernumerary, and absent muscles in each compartment. The variations were only found on the right side and predominant in females: 2 out of 11 (18.18%) hands containing a space with a supernumerary muscle; 1 out of 11 (9.09%) hands having a space with a double muscle; and 1 out of 11 (9.09%) hands having a compartment with a unipennate muscle. In males, 1 out of 9 (11.11%) hands had a compartment with a supernumerary muscle. The mean midpoint length of each muscle in females and males in both hands from the first to the fourth muscle, respectively, was documented. In females on the left: 46.79 ± 3.56; 42.62 ± 3.57; 49.02 ± 4.21; 41.66 ± 2.15 and right: 47.30 ± 2.49; 39.27 ± 4.14; 45.69 ± 4.64; 38.12 ± 4.08. In males, it was on the left: 50.01 ± 3.95; 41.98 ± 3.79; 47.90 ± 4.83; 41.79 ± 4.25, and on the right: 46.65 ± 2.09; 39.01 ± 4.25; 47.47 ± 3.41; 38.31 ± 4.40. The mean midpoint length of the DIM was relatively higher on the left hand compared to the right hand in both females and males. In this study, variations regarding the supernumerary muscle, double interosseous space, and unipennate muscles were only observed on the right-hand side and predominantly in females, an insight that may guide in the treatment of fractures, stiffness of the hand, and compartment syndromes.

Los músculos interóseos dorsales (DIM) son músculos intrínsecos de la mano ubicados dorsalmente entre los huesos metacarpianos, que desempeñan un papel en la abducción de los dedos. Las variaciones anatómicas de estos músculos en términos de forma y longitud están bien documentadas, pero las variaciones con respecto al sexo y la lateralidad están poco exploradas. El objetivo de este estudio fue investigar la morfología y morfometría de los DIM de la mano con respecto al dimorfismo sexual y la lateralidad. Para este estudio se utilizaron veinte cadáveres humanos pertenecientes a individuos blancos (n = 40 manos) con sexo y lateralidad conocidos. Los DIM se diseccionaron y observaron para determinar su morfología. Además, se utilizó un calibrador digital para medir la longitud del punto medio del DIM. El origen y la inserción de todos los DIM fueron normales y la mano izquierda no tenía músculos adicionales, supernumerarios y ausentes en cada compartimento. Las variaciones se encontraron sólo en el lado derecho y predominaron en el sexo femenino: 2 de 11 (18,18%) manos contenían un espacio con un músculo supernumerario; 1 de cada 11 (9,09%) manos presentando un espacio con doble músculo; y 1 de cada 11 (9,09%) manos presentaba un compartimento con músculo unipenate. En los hombres, 1 de cada 9 (11.11%) manos tenía un compartimento con un músculo supernumerario. Se documentó la longitud media del punto medio de cada músculo en mujeres y hombres en ambas manos desde el primer al cuarto músculo, respectivamente. En mujeres de izquierda: 46,79 ± 3,56; 42,62 ± 3,57; 49,02 ± 4,21; 41,66 ± 2,15 y derecha: 47,30 ± 2,49; 39,27 ± 4,14; 45,69 ± 4,64; 38,12 ± 4,08. En los varones fue hacia la izquierda: 50,01 ± 3,95; 41,98 ± 3,79; 47,90 ± 4,83; 41,79 ± 4,25, y a la derecha: 46,65 ± 2,09; 39,01 ± 4,25; 47,47 ± 3,41; 38,31 ± 4,40. La longitud media del punto medio del DIM fue relativamente mayor en la mano izquierda en comparación con la derecha tanto en mujeres como en hombres. En este estudio, las variaciones con respecto al músculo supernumerario, el doble espacio interóseo y los músculos unipennados sólo se observaron en el lado derecho y predominantemente en el sexo femenino, un conocimiento que puede guiar en el tratamiento de fracturas, rigidez de la mano y síndromes compartimentales.

Absent right common carotid artery with associated anterior communicating aneurysm: embryology and imaging correlation.

PURPOSE: To report an unusual absent right common carotid artery with embryological and clinical emphasis. METHODS: A 63-year-old female with a multilobulated anterior communicating artery saccular aneurysm was referred to our center for definite treatment. An analysis of her carotid system on CTA and DSA with 3D modeling was performed to assess the embryology of an absent right common carotid and its association with aneurysm development. RESULTS: Cerebral angiogram demonstrated an absent right common carotid artery and separate origin of the internal and external right carotid arteries arising from the brachiocephalic trunk. CONCLUSION: Absence of the common carotid artery is an uncommon anatomical variant, usually asymptomatic and commonly associated with other vascular abnormalities. It is important to be familiar with the association between this anatomical variant given its hemodynamic stress, high risk of stroke, and aneurysm formation.

Anatomy of vertebral artery hypoplasia and its relationship with clinical implications: a systematic review and meta-analysis of prevalence.

PURPOSE: The vertebral artery (VA) is a vital branch of the subclavian artery, coursing through the transverse foramina of the cervical vertebrae, and playing a crucial role in irrigating the posterior region of the arterial cerebral circle, also known as the Polygon of Willis. Among the various possible alterations that can affect the VA, vertebral artery hypoplasia (HAV) emerges as a significant variant. This study aims to discern the anatomical features of HAV and its correlation with the clinical conditions of the posterior cerebral circulation. METHODS: The databases Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS were searched until January 2024. Two authors independently performed the search, study selection, and data extraction. Methodological quality was evaluated with an assurance tool for anatomical studies (AQUA). Pooled prevalence was estimated using a random effects model. RESULTS: A total of 24 studies met the established selection criteria, with a total of 8847 subjects. In this study, 6 articles were included for the meta-analysis with a total of subjects. The average prevalence of VAH reported in each study was 11% (95% CI 10-12%); the studies had a heterogeneity of 41% based on the funnel plot and a low risk of bias. CONCLUSION: The prevalence of VAH is low, but in the presence of this condition, the changes are mainly in diameter rather than morphological. If it is present, some clinical safeguards must be taken to avoid complications such as stroke.

Os trigonum: a discussion of its role in posterior ankle impingement syndrome and a meta-analysis of its prevalence.

PURPOSE: the os trigonum is a supernumerary bone that may lead to posterior ankle impingement syndrome. The present study aims to assess the prevalence of this bone. METHODS: A meta-analysis regarding the presence of the os trigonum was performed. For this, the MEDLINE and SciElo databases were searched using "os trigonum" as the keyword. Only original articles, theses, books, dissertations, and monographs were included. Papers with a sample size of < 50 individuals were excluded. The data extracted from the articles were: the total sample size, the prevalence of the trigonum, the method of analysis, the region of the sample, and data regarding sex and side (left or right). Statistical analysis was performed using MedCalc Statistical Software version 14.8.1 (MedCalc Software bvba, Ostend, Belgium). The heterogeneity between the studies was assessed using the I² estimation and the Cochran Q test. For all analyses, a random effect was used and a value of p < 0.05 was considered significant. RESULTS: 249 papers were found, while 18 were included in the meta-analysis. A total of 17,626 ankles were included. The pooled prevalence of the os trigonum was 10.3% (95% CI 7-14.1%) in the present study. There was no significant difference regarding sex or side, while studies conducted in imaging exams showed a higher prevalence in comparison to cadaveric studies. CONCLUSION: Our results suggest that the os trigonum is relatively common. Knowledge of the prevalence of the os trigonum may help surgeons and clinicians diagnose posterior ankle impingement syndrome.

Infraorbital canal variants and its clinical and surgical implications. A systematic review.

BACKGROUND: Recent literature highlights anomalous cranial nerves in the sinonasal region, notably in the sphenoid and maxillary sinuses, linked to anatomical factors. However, data on the suspended infraorbital canal (IOC) variant is scarce in cross-sectional imaging. Anatomical variations in the sphenoid sinuses, including optic, maxillary, and vidian nerves, raise interest among specialists involved in advanced sinonasal procedures. The infraorbital nerve's (ION) course along the orbital floor and its abnormal positioning within the orbital and maxillary sinus region pose risks of iatrogenic complications. A comprehensive radiological assessment is crucial before sinonasal surgeries. Cone-beam computed tomography (CBCT) is preferred for its spatial resolution and reduced radiation exposure. OBJECTIVE: The aim of this study was to describe the prevalence of anatomical variants of the infraorbital canal (IOC) and report its association with clinical condition or surgical implication. METHODS: We searched Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception up to June 2023. Two authors independently performed the search, study selection, data extraction, and assessed the methodological quality with assurance tool for anatomical studies (AQUA). Finally, the pooled prevalence was estimated using a random effects model. RESULTS: Preliminary results show that three types are prevalent, type 1: the IOC does not bulge into the maxillary sinus (MS); therefore, the infraorbital foramen through the anterior wall of MS could be used for identification of the ION. Type 2: the IOC divided the orbital floor into medial and lateral aspects. Type 3: the IOC hangs in the MS and the entire orbital floor lying above the IOC. From which the clinical implications where mainly surgical, in type 1 the infraorbital foramen through the anterior wall of MS could be used for identification of the ION, while in type 2, since the lateral orbital floor could not be directly accessed an inferiorly transposition of ION is helpful to expose the lateral orbital wall directly with a 0 scope; or using angled endoscopes and instruments, however, the authors opinion is that direct exposure potentially facilitates the visualization and management in complex situations such as residual or recurrent mass, foreign body, and fracture located at the lateral aspect of the canal. Lastly, in type 3, the ION it's easily exposed with a 0° scope. CONCLUSIONS: This systematic review identified four IOC variants: Type 1, within or below the MS roof; Type 2, partially protruding into the sinus; Type 3, fully protruding into the sinus or suspended from the roof; and Type 4, in the orbital floor. Clinical recommendations aim to prevent nerve injuries and enhance preoperative assessments. However, the lack of consistent statistical methods limits robust associations between IOC variants and clinical outcomes. Data heterogeneity and the absence of standardized reporting impede meta-analysis. Future research should prioritize detailed reporting, objective measurements, and statistical approaches for a comprehensive understanding of IOC variants and their clinical implications. Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/UGYFZ .

Frequency and characterization of the accessory heads of the biceps brachii: A multicentric cadaveric study.

PURPOSE: The biceps brachii muscle (BBM) is a large and thick muscle on the ventral portion of the upper arm. The scientific literature reports the existence of extra heads. OBJECTIVE: The present work investigated the frequency of occurrence of BBM accessory head(s) in four different Anatomy Laboratories at universities in Northeast Brazil. MATERIAL AND METHODS: Once the upper limbs with an anatomical variation of the BBM heads were identified, the accessory head was evaluated for morphometric characterization (the length, width, and thickness). RESULTS: The sample consisted of 249 upper limbs and the outcomes were 26 members with BBM accessory heads (10.44% of the total sample). Among the 26 members studied was found a single accessory head in 22 (84.62%), two accessory heads in 3 (11.54%), and three accessory heads in 1 (3.85%). BBMs with one, two, and three accessory heads were found, with different origins. The average length, width, and thickness of these accessory heads were 169.39mm, 10.25mm, and 3.39mm, respectively. CONCLUSION: The frequency of BBM accessory heads in a population of northeastern Brazil in this cadaveric study was 10.44%.

The variations of osseous structure of the internal acoustic canal: an anatomical study.

OBJECTIVES: The internal acoustic meatus is an osseous canal that connects the inner ear to the posterior cranial fossa. It is located in the petrous portion of the temporal bone. A thin cribriform osseous plate known as the fundus is situated at the lateral end of the canal. This study assesses the structural and numerical variations of the fundus formations. METHODS: Fifty-four temporal bones of unknown gender and age were examined with the surgical microscope. RESULTS: The temporal bones analyzed were 46.2% right-sided and 53.7% left-sided. Only one temporal bone had two parallel transverse crests, while three had a single anterior crest that split into two branches posteriorly. The number of foramina at the transverse crest varied, with 29.6% having none, 48.1% having a single foramen, and 22.2% having several foramina. An anterior crest structure was seen in 53.7% of the temporal bones, with 5% having a slightly constricted entry to the facial canal. In cases with a single nerve foramen, 48.1% had one, while 51.8% had more than one, including examples with three or four foramina. A crest was found between the foramina of the single nerve in 7% of patients. Furthermore, a crest between the saccular nerve foramen and the high fiber foramina was seen in 25.9% of cases, and 5% had two saccular nerve foramina. CONCLUSION: We think that revealing the anatomical, structural and numerical variations in the fundus will be useful in explaining the disease-symptom relationship. LEVEL OF EVIDENCE: Level 4.

Anatomical variations of recurrent laryngeal nerve: a systematic review and meta-analyses.

PURPOSE: The aim of this systematic review and meta-analysis was to systematically review and perform a meta-analysis on the anatomical variations of the RLN. METHODS: We performed online research for studies that addressed anatomical variations of the RLN and laterality, published between 2015 and 2021. We found 230 articles, and nine were included. RESULTS: Eight variations were found, with Type I prevailing (41.17%; 95% CI 19.44-64.88), extra laryngeal divergence of the RLN. The other types were: II-fan shape; III-distance greater than 5 mm to the cricothyroid joint; IV-thickening and adipopexy in the elderly; V-non-recurrent laryngeal nerve; VI-intracranial branch; VII-tortuous ascending RLN; and VIII-combination between the inferior branch of the NV and the ascending trunk of the RLN. Types I (p = 0) and III (p < 0.01) prevailed on the left and types II (p < 0.01) and V (p < 0.01) on the right. CONCLUSIONS: It was observed that variations occurred due to the path of the RLN to the entrance to the larynx, its shape, and the age of the evaluated individual. The most frequent variation and side were, respectively, Type I, extra laryngeal divergence and left.

Systematic review and meta-analysis of right subclavian artery variants and their correlation with cervical-thoracic clinical conditions.

BACKGROUND: A high incidence of anatomical variations in the origin of the branches of the aortic arch has been reported, Nowadays, this variation is considered the most frequent in the aortic arch, its prevalence being estimated between 0.5% and 2.5% of the population. To understand its origin, knowledge of embryonic development is necessary. METHODS: We searched the MEDLINE, Scopus, Web of Science, Google Scholar, Cumulative Index to Nursing and Allied Health Literature, and Latin-American literature and caribean of health sciences databases with dates ranging from their inception to June 2023. Study selection, data extraction, and methodological quality were assessed with the guaranteed tool for anatomical studies (Anatomical Quality Assurance). Finally, the pooled prevalence was estimated using a random effects model. RESULTS: Thirty-nine studies were found that met the eligibility criteria. Twenty studies with a total of 41,178 subjects were included in the analysis. The overall prevalence of an ARSA variant was 1% (95% confidence interval = 1%-2%), the clinical findings found are that if ARSA is symptomatic it could produce changes in the hemodynamic function of the thoracocervical region in addition to other associated symptomatic complications in surrounding structures. CONCLUSIONS: ARSA can cause several types of alterations in the cervical or thoracic region, resulting in various clinical complications, such as lusory dysphagia. Hence, knowing this variant is extremely important for surgeons, especially those who treat the cervico-thoracic region. The low prevalence of ARSA means that many professionals are completely unaware of its existence and possible course and origin. Therefore, this study provides detailed knowledge of ARSA so that professionals can make better diagnoses and treatment of ARSA.

The Accessory Muscular Head of the Triceps Brachii Muscle with Tendinous Attachment / Cabeza Muscular Accesoria del Músculo Triceps Braquial con Inserción Tendinosa

SUMMARY: Variations in the triceps brachii muscle are uncommon, and especially limited reports exist on the accessory heads of tendinous origin that attach near the upper medial part of the humerus. During anatomical training at Nagasaki University School of Medicine, the accessory head of the triceps brachii muscle was observed on the right upper arm of a 72-year-old Japanese female. It arose tendinously from the medial side of the upper humerus, then formed a muscle belly and joined the distal side of the long head. This accessory head had independent nerve innervation, and the innervating nerve branched from a bundle of the radial nerve, which divided the nerve innervating the long head and the posterior brachial cutaneous nerve. The origin of the innervation of the accessory head was the basis for determining that this muscle head was an accessory muscle to the long head of the triceps brachii muscle. Embryologically, we discuss that part of the origin of the long head of the triceps brachii muscle was separated early in development by the axillary nerve and the posterior brachial circumflex artery, and it slipped into the surgical neck of the humerus and became fixed there. The accessory head crossed the radial nerve and deep brachial artery. When clinicians encounter compression of the radial nerve or profunda brachii artery, they should consider the presence of accessory muscles as a possible cause.

Las variaciones en el músculo tríceps braquial son poco comunes y existen informes especialmente limitados sobre las cabezas accesorias de origen tendinoso que se insertan cerca de la parte medial superior del húmero. Durante un entrenamiento anatómico en la Facultad de Medicina de la Universidad de Nagasaki, se observó la cabeza accesoria del músculo tríceps braquial en la parte superior del brazo derecho de una mujer japonesa de 72 años. Se originaba tendinosamente desde el lado medial de la parte superior del húmero, luego formaba un vientre muscular y se unía al lado distal de la cabeza larga. Esta cabeza accesoria tenía inervación nerviosa independiente, cuyo nervio se ramificaba a partir de un ramo del nervio radial, que dividía el nervio que inervaba la cabeza larga y el nervio cutáneo braquial posterior. El origen de la inervación de la cabeza accesoria fue la base para determinar que esta cabeza muscular era un músculo accesorio de la cabeza larga del músculo tríceps braquial. Embriológicamente, discutimos que parte del origen de la cabeza larga del músculo tríceps braquial se separó temprananamente en el desarrollo por el nervio axilar y la arteria circunfleja braquial posterior, y se deslizó hacia el cuello quirúrgico del húmero y quedó fijado allí. La cabeza accesoria cruzaba el nervio radial y la arteria braquial profunda. Cuando los médicos encuentran compresión del nervio radial o de la arteria braquial profunda, deben considerar la presencia de mús- culos accesorios como una posible causa.

Anatomical Diversity in Femur bones: Understanding the Morphological Variability for Surgical and Prosthetic Applications / Diversidad Anatómica en Huesos Fémur: Comprensión de la Variabilidad Morfológica para Aplicaciones Quirúrgicas y Protésicas

SUMMARY: The femur, the body's longest bone, plays a critical role in orthopaedics and radiology. Understanding its anatomy, particularly the neck-shaft angle (NSA), is vital for diagnosing bone issues and designing hip implants. While some Asian populations' femur measurements have been studied, there is a research gap concerning Sri Lankans. This study aimed to fill this gap by examining the proximal femur's anatomy in the Sri Lankan population. We analysed 45 adult human femurs (26 right, 19 left) of unknown sex, ethically sourced from the University of Sri Jayewardenepura. Femurs with fractures or pathologies were excluded. Precise measurements were recorded using digital vernier callipers, with millimetre accuracy. Parameters included mean femoral length, vertical and transverse femoral head diameters, neck axis and neck length. Each measurement was taken three times to minimize subjectivity. Right femurs had a mean length of 42.8 mm (SD±2.64), while left femurs measured 43.53 mm (SD±3.27). Mean NSA was 125.78º (SD±4.45) for left femurs and 127.59º (SD±2.06) for right. Mean femoral head diameters were 4.09mm (SD±0.30) (right) and 4.12mm (SD±0.31) (left). Mean anterior neck lengths of the right and left were 2.61 (SD±0.54) and 2.71(SD±0.50) respectively. Comparing our findings with other Asian populations highlighted significant variations in femur measurements. These discrepancies emphasize the need for population-specific data for orthopaedic interventions and raise questions about the suitability of imported prosthetics. Differences in femur length, neck length, and NSA between sides suggest potential challenges in using implants designed for one side on the other. This study underscores the necessity of population-specific data in orthopaedics, as femur measurements differ even among Asian populations. Further research and statistical analysis are essential for tailoring orthopaedic solutions to individual populations. The findings also suggest a potential need for locally manufactured prosthetics to better suit the Sri Lankan population.

El fémur, el hueso más largo del cuerpo, desempeña un papel fundamental en ortopedia y radiología. Comprender su anatomía, en particular el ángulo cuello-diáfisis (NSA), es vital para diagnosticar problemas óseos y diseñar implantes de cadera. Si bien se han estudiado las medidas del fémur de algunas poblaciones asiáticas, existe un vacío en la investigación sobre los habitantes de Sri Lanka. Este estudio tuvo como objetivo examinar la anatomía del fémur proximal en la población de Sri Lanka. Analizamos 45 fémures humanos adultos (26 derechos, 19 izquierdos) de sexo desconocido, obtenidos éticamente de la Universidad de Sri Jayewardenepura. Se excluyeron fémures con fracturas o patologías. Se registraron mediciones precisas utilizando calibradores vernier digitales, con precisión milimétrica. Los parámetros incluyeron la longitud femoral media, los diámetros vertical y transversal de la cabeza femoral, el eje del cuello y la longitud del cuello. Cada medición se tomó tres veces para minimizar la subjetividad. Los fémures derechos tuvieron una longitud media de 42,8 mm (DE ± 2,64), mientras que los fémures izquierdos midieron 43,53 mm (DE ± 3,27). La NSA media fue de 125,78º (DE±4,45) para el fémur izquierdo y de 127,59º (DE±2,06) para el derecho. Los diámetros medios de la cabeza femoral fueron 4,09 mm (DE ± 0,30) (derecha) y 4,12 mm (DE ± 0,31) (izquierda). Las longitudes medias del cuello anterior de la derecha y la izquierda fueron 2,61 (DE ± 0,54) y 2,71 (DE ± 0,50) respectivamente. La comparación de nuestros hallazgos con otras poblaciones asiáticas destacó variaciones significativas en las medidas del fémur. Estas discrepancias enfatizan la necesidad de datos específicos de la población para las intervenciones ortopédicas y plantean dudas sobre la idoneidad de las prótesis importadas. Las diferencias en la longitud del fémur, la longitud del cuello y la NSA entre lados sugieren posibles desafíos al utilizar implantes diseñados para un lado en el otro. Este estudio subraya la necesidad de datos específicos de la población en ortopedia, ya que las mediciones del fémur difieren incluso entre las poblaciones asiáticas. Es esencial realizar más investigaciones y análisis estadísticos para adaptar las soluciones ortopédicas a poblaciones individuales. Los hallazgos también sugieren una posible necesidad de prótesis fabricadas localmente para adaptarse mejor a la población de Sri Lanka.