Morphological classification of the septomarginal trabecula in humans.

Although the septomarginal trabecula is a well-known anatomical structure, there continue to be different ways of studying it. In this study, we dissected the muscle bundles that form it, and this has enabled us to present a new classification based on the origin, path, and termination of these bundles. This study was conducted on 99 hearts removed from the cadavers of adult humans aged 18 to 82 years, of which 72 were male and 27 were female. The septomarginal trabecula presents two components in its composition: one septal and the other septal- papillary, i.e. extending from the septum to the anterior papillary muscle. The septal component may be visible macroscopically, forming a fleshy third-order column, or may only be visible by means of dissection. The septal-papillary component is always visible and is a fleshy column of either second-order or third- -order type. Another parameter takes into consideration the papillary-parietal connection, i.e. the junction of the septomarginal trabecula with the anterior papillary muscle, which may be single or present ramifications to the anterior wall and/or apex. Taking these criteria as references, we have classified the septomarginal trabecula into eight types.

Anatomy of the septomarginal trabecula in Landrace pig hearts.

The limitations on the availability of organs for transplantation have aroused interest in research on xenotransplantation of whole organs or certain parts of them. Thus, studies that confirm or reject similarities between the organs of different animals have started to have important clinical applications. In the present study, we investigated the septomarginal trabecula in 34 hearts from Landrace pigs with the aim of observing their similarities with the septomarginal trabecula in humans. In pigs, the muscle bundle of the septomarginal trabecula and the right branch of the stimulating complex are dissociated. The right branch is a narrow bridge that, after going out from the upper part of the interventricular septum, is attached to the upper part of the anterior papillary muscle. On the other hand, the muscle bundle of the septomarginal trabecula is generally a resistant crest that goes from the lower part of the septum to the lower part of the anterior papillary muscle. The septomarginal trabecula presents marked anatomical differences between humans and pigs.

The anatomy of the human thyroid veins and its surgical application.

The present study was motivated by the importance of the thyroid veins in surgery in the anterolateral cervical region, particularly in tracheostomies, the need for information on modern diagnostic imaging techniques and the lack of specific publications on the subject. The research was performed on 30 adult human specimens by means of dissection and measurement. The superior thyroid vein was constant, single on both sides (83.3%), with its termination (87.1%) at the internal jugular vein (97.2%), either isolated (29.4%) or with other veins, mostly the lingual vein (52.1%), and was located between 1.0 and 2.5 cm below a plane that passes the upper margin of the hyoid bone. The medial thyroid vein, when present, was not constant (43.3%), was single (96.1%), terminated in the internal jugular vein and was located between 2.0 and 4.0 cm from the mid-sagittal line (84.6%). The inferior thyroid vein was constant (96.7%) and varied in number, with one (62.1%), two (27.6%) or even five occurring, and was formed by the confluence of two primary branches (78.6%) as a result of the abundance of anastomoses coming from the lower and medial parts of the gland. The number of terminations corresponded to the number of veins, at the level of the 5(th) to 8(th) rings in 36.9%, of the 9(th) to 10(th) rings in 34.8% and of the 11(th) to 14(th) rings in 28.3%, and occurred in the right brachiocephalic vein (26.1%), in the left brachiocephalic vein (60.9%) or in both veins (13.0%).

Morphometric study of the tricuspid valve in dogs.

An anatomical study of the tricuspid valve was performed in the hearts of 45 dogs using a method of dissection which preserves the integrity of the valve. Morphometrical criteria such as the width of the cusp base and larger depth of cusp and morphological criteria such as the number of tendinous cords, the perimeter of the fibrous ring and the properties of the papillary muscle were adopted for the characterization of a cusp. The tricuspid valve was not consistent with three cusps, but it was observed to present 2, 4 or 5 cusps in 68% of the cases.

Neurovascular pedicles of the tibialis anterior muscle in children / Pedículos neurovasculares del músculo tibial anterior en niños

The importance of the tibialis anterior muscle in infantile orthopedic transposition surgeries, as in myelomemngoceles, it bases this research about the neurovascular pedicles of the tibialis anterior muscle. The study was conducted on 34 legs of human cadavers that were one year old or younger at the time of death. It was observed that the tibialis anterior muscle most frequently presented from 7 to 10 arterial branches (52.4 percent). In 97.1 percent of cases these branches were derived from the anterior tibial artery. In one case the anterior tibial artery was missing and the muscle was supplied by the fibular artery. Thirty-nine and seven tenths percent of arterial branches entered the superior third of the muscle; the middle third received 40.1 percent of the branches and the inferior third received 20.2 percent of the branches. The deep fibular nerve exclusively supplied the innervation, which in91.2 percent of cases, gave off from 2 to 4 branches to the muscle, mainly to the superior (46.2 percent) and middle third (43.0 percent). Most frequently, there were two neurovascular pedicles supplying the superior third and one supplying the middle third.

La importancia del músculo tibial anterior en cirugías de transposición ortopédica en niños, así como en casos de mielomeningocele, fundamenta su estudio respecto a sus pedículos neurovasculares. El estudio se realizó en 34 miembros inferiores de cadáveres de niños de un año o menos de edad. Se observó que el músculo tibial anterior presentaba con frecuencia 7 a 10 ramas arteriales (52,4 por ciento). En 97,1 por ciento de los casos estos ramos eran derivados de la arteria tibial anterior. En dos casos, la arteria tibial anterior estaba ausente y el músculo suplió su irrigación con la arteria fibular. En relación a la entrada de las ramas, 39,7 por ciento lo hacen en el tercio superior del músculo. El tercio medio recibe 40,1 por ciento de las ramas y el tercio inferior recibe 20,2 por ciento de ellas. El nervio fibular profundo es la fuente principal de inervación, en 91,2 por ciento de los casos provee 2 a 4 ramos para el músculo, de ellos el 46,2 por ciento termina en el tercio superior y el 43 por ciento en el tercio medio. Con mayor frecuencia, existen dos pedículos neurovasculares supliendo el tercio superior y uno supliendo el tercio medio del músculo tibial anterior.

Anatomical indicators of dominance between the coronary arteries in swine.

The interest in experimental use of coronary arteries of swine as a stage towards their application in human hearts justifies the need for obtaining a detailed anatomical understanding of those arteries, particularly to evaluate similarities and differences. However, we did not find any citations about anatomical indicators of coronary dominance among swine in the literature. Many authors have used the crux cordis and the origin of the posterior interventricular branch as references for defining three types of pattern in human hearts: right, balanced and left dominance. We used 30 hearts fixed in 10% formalin from male and female Landrace swine aged five to six months, weighing 80 to 110 kg. The branch corresponding to the subsinuosal interventricular sulcus came from the right coronary artery (96.7%) or from both coronary arteries (3.3%). The subsinuosal interventricular branch presented at least one small branch that went beyond the crux cordis. The apical area presented predominance of the paraconal interventricular (left anterior descending) branch in 43.3%, the subsinuosal interventricular branch in 23.3% and presence of both arteries in 33.3%. The left coronary artery emitted 54.5% of the ventricular branches and the right coronary artery 46.5%. Taking the crux cordis and the subsinuosal interventricular branch as references, the arterial pattern in swine hearts is right dominance. The diversity of the apical pattern and the balance in the distribution of ventricular branches do not allow this to be used as an approach in isolation. The similarities between human and swine hearts also apply to the coronary artery pattern.

The subscapular artery and the thoracodorsal branch: an anatomical study.

The motive for this research was the use of the muscles of the scapular region in transposition, transplantation and reparative surgery and the need for more detailed knowledge of the blood supply to these muscles. In addition, the subscapular arterial tree may be used as a source of microvascular grafts to replace damaged or diseased portions of arteries, particularly in the hand and forearm. The research was conducted on 60 sides of corpses of adults of both sexes. It was noticed that the subscapular artery was present in 96.7% of cases and originated laterally to the pectoralis minor muscle in 76.7% of cases. The average calibre was 5.0 mm, and in 73.2% of cases it measured between 4.0 and 5.9 mm. The average length was 18.0 mm, ranging from 10.0 to 29.9 mm (76.7%). It presented in its course important relations with the axillary nerve (69%) and with the radial nerve (82.8%). Its branches were collateral (subscapular muscle - 61.3%) and terminal (except for the circumflex scapular artery), leading to the following muscles: serratus anterior (43.9%), latissimus dorsi (27.6%), and subscapular (23.3%). The thoracodorsal artery, one of the terminal branches, most frequently showed a calibre of between 2.0 and 3.9 mm (70.3%), collateral branches in 85.0%, was mainly distributed to the subscapular muscle (36.7%) and to the serratus anterior muscle (29.0%) and had terminal branches to the following muscles: latissimus dorsi (44.1%), serratus anterior (40.5%) and the subscapular (12.5%). The serratus anterior muscle received one branch in 39.5% and two branches in 41.9%, while the latissimus dorsi muscle received one branch in 66.7% and two branches in 23.1%.