Anatomy History

Anatomy History

As you bend with the rigid blade of your scalpel over the unknown corpse, remember that this body was born of the love of two souls, it grew cradled by the faith and hope of the one who wrapped it within. He smiled and dreamed the same dreams of children and youth. He certainly loved and was loved, waited and cherished a happy tomorrow, and missed the others who left. Now it lies on the cold slate, without a tear being shed through it, without a single prayer. Your name, God only knows. But inexorable fate has given him the power and grandeur to serve humanity. The humanity that passed through it indifferently

                                                                                                                                               (Rokitansky, 1876)

Anatomical knowledge of the human body dates from five hundred years before Christ in southern Italy with Alcméon de Crotona, who performed dissections on animals. Shortly thereafter, a clinical text from the Hippocratic School discovered the anatomy of the shoulder as it had been studied with dissection. Aristotle mentioned anatomical illustrations when referring to paradigms, which were probably figures based on animal dissection. In the third century BC, the study of anatomy advanced considerably in Alexandria. Many discoveries made there can be attributed to Herophilus and Erasistratus, the first who systematically performed human dissections. From the year 150 A..C. human dissection was again prohibited for ethical and religious reasons. Anatomical knowledge about the human body continued in the Hellenistic world, but was only known through animal dissections. In the second century AD Galen dissected almost everything, monkeys and pigs, then applied the results obtained in human anatomy, almost always correctly; however, some errors were inevitable due to the impossibility of confirming the findings in human cadavers. Galen nevertheless developed the doctrine of 'final cause', a theological system that required all findings to confirm physiology as it understood it.

However, the anatomical illustrations of the classical period did not reach us, being the series of five figures #8221; Medieval bones, veins, arteries, internal organs, and nerves are probably copies of earlier drawings. Invariably, figures are depicted in an open frog-like position, to demonstrate the various systems, sometimes a sixth figure representing a pregnant woman and male or female sexual organs is added. In the old bas-reliefs, cameos and bronzes often appear as skeletons and shrunken, skin-covered bodies (called lemurs) of a magical or symbolic character rather than schematic and without any didactic purpose.

It seems that the study of human anatomy has resumed more for practical than intellectual reasons. War was not a local affair and means were needed to repatriate the bodies of the dead in combat. Embalming was sufficient for short journeys, but greater distances such as the Crusades introduced the practice of bone cooking. The papal bull De Boniface VIII (1300), which some historians mistakenly believed to prohibit human dissection, tried to abolish this practice. The most important reason for human dissection was the desire to know the cause of death for essentially medico-legal reasons, to find out what had killed an important person, or to elucidate the nature of the plague or other infectious disease.

The verb & #8220; dissect & #8221; It was also used to describe the increasingly frequent cesarean section. The manuscript tradition of the medieval period was not based on the natural world. The previous illustrations were accepted and copied. In general, writers' ability was limited, and in examining natural reality they made at least some errors of both concept and technique. Things #8220; were seen & #8221; such as the ancient and realistic illustrations were considered as a short circuit of the method of study itself.

Anatomy was not an independent discipline, but an adjunct to the surgery, which at that time was relatively crude and gathered all the proper points for bleeding. All the while anatomy boasted this opposite quality to practice, the unrealistic and schematic figures were sufficient.

The first book illustrated with more than painted print images was the work of Ulrich Boner Der Edelstein. It was published by Albrecht Plister in Banberg after 1460 and its illustrations were more than ordinary decorations. In 1475 Konrad Megenberg published his Buch der Natur, which included various wood engravings depicting fish, birds and other animals, as well as various plants. These figures, like many others in books on nature and encyclopedias of this period, are within the manuscript tradition and are hardly identifiable.

Among the many factors that contributed to the development of illustrative technique in the early sixteenth century, two took a prominent place: the first was the end of the manuscript tradition of copying ancient drawings and converting nature into a primary model. The conviction was reached that the most appropriate for man was the natural world and not posterity. St. Thomas Aquinas' scholasticism had inadvertently paved the way by separating the natural from the supernatural world, theology prevailing over natural science. The second factor that influenced the development of scientific illustration for teaching was the slow introduction of better techniques. In the beginning editors, with a purely quantitative criterion, thought that with the press they could make large numbers of reproductions easily and cheaply. Only later did they recognize the importance of each illustration being identical to the original. The ability to repeat exactly pictorial reproductions of what was observed constituted the distinguishing feature of several scientific disciplines, which dismissed their earlier support for tradition and acceptance of a methodology, which was descriptive at first and later experimental.

The earliest printed anatomical illustrations are based on the medieval manuscript tradition. The Fasciculus Medicinae was a collection of texts by contemporary authors for practitioners, which has reached many editions. In the first one (1491), the first woodcut was used for anatomical figures. The illustrations represent human bodies showing the bleed points, and lines that join the figure to the explanations printed in the margins. The dissections were designed in a primitive and unrealistic manner.

In the Second Edition (1493), the positions of the figures are more natural. Hieronymous Brunschwig's texts (circa 1450-1512) continued to use descriptive illustrations. The final chapter of a work by Johannes Peyligk (1474-1522) consists of a brief anatomy of the human body as a whole, but the eleven wood engravings it includes are more than later schematic representations of the Arabs. In George Reisch's Margarita Philosophica (1467-1525), which is an encyclopedia of all sciences, some innovations have been placed in traditional wood engravings, and abdominal viscera are realistically represented.

In addition to these anatomical texts intended specifically for medical students and physicians, many other pages with anatomical figures were printed, titled not in Latin (like all works for doctors), but in various common languages. There was great interest, for example, in the conception and formation of the human fetus. Frequent use of the phrase & #8220; know yourself & #8221; speaks of philosophical and essentially non-medical orientation. The & #8220; Dance of Death & #8221; It became a very popular theme, especially in German-speaking countries after the Black Death, and surprisingly, the depictions of the skeletons and human anatomy of the artists who drew them are better than those of the anatomists.

Renaissance artists of the fifteenth century became increasingly interested in human forms, and the study of anatomy was a necessary part of the formation of young artists, especially in northern Italy.

Leonardo da Vinci (1452-1519) was the first artist who considered anatomy beyond the merely pictorial point of view. He made preparations he soon drew, of which more than 750 are conserved, and represent the skeleton, muscles, nerves and vessels. The illustrations were often completed with physiological notes. Leonardo's accuracy is greater than Vesalio's and his artistic beauty remains unchanged. Its correct appreciation of spinal curvature has been forgotten for over a hundred years. It correctly represented the position of the fetus in utero and was the first to point out some known anatomical structures. Only a few contemporaries saw their pamphlets, which undoubtedly were not published until the end of the last century.

Michelangelo Buonarotti (1475-1564) spent at least twenty years acquiring anatomical knowledge through his personal dissections, especially in the Holy Spirit convent of Florence. He later exposed the evolution to which he was subjected, considering anatomy not useful for the artist until he thought that he had an interest in himself, albeit always subordinated to art.

Albrecht Dürer (1471-1528) wrote works of mathematics, distillation, hydraulics, and anatomy. His treatise on the proportions of the human body was published after his death. His concern for human anatomy was entirely aesthetic, ultimately deriving an interest in the classical canons through which beauty could be acquired.

With the important exception of Leonardo, whose drawings were not available to seventeenth-century anatomists, the Renaissance artist was only a secondary anatomist. Important contributions were still made in the realistic representation of the human form (such as the use of perspective and shading to suggest depth and three-dimensionality), and true scientific advances required the collaboration of professional anatomists and artists. When anatomists could realistically represent the correct anatomical knowledge, a period of intense research began throughout Europe, especially in northern Italy and southern Germany. The best representative of this group is Jacob Berengario da Capri (+1530), author of Commentaria super anatomica mundini (1521), which contains the first anatomical illustrations taken from the natural. In 1536 Cratander published in Basel an edition of Galen's works, which included figures, especially of osteology, made in a very realistic way. From as early as 1532, Charles Estienne prepared in Paris a work in which he emphasized the complete pictorial representation of the human body.

VESAL

One of the first and most accurate solution for a perfect reproduction of graphic representations was found in the illustrations published in the anatomical treatises of Andrés Vesálio (1514-1564), which culminated in his De humanis corpori, manufactured in 1553, one of the most important books in history. of the man. Vesalius also proved that they are not equal in all individuals. He recounted his surprise at finding numerous errors in Galen's works, and we must stress the importance of his refusal to accept anything just because he found it in the writings of the great Greek physician. Undoubtedly, despite denying the existence of the holes that Galen claimed to exist in communicating the cardiac cavities, he was in any case a follower of Galenic physiology. The differences that separated his anatomical knowledge from Galen's were magnified, beginning with Vesalius himself.

Perhaps he thought a controversy was a way of drawing attention. He then maintained a fierce dispute with his master Jacques du Bois (or Sylvius, in Latin form), who was a convinced Galenist whose only answer, given the differences between some structures as seen by Vesalius and as he had described them, was that humanity must have changed it during these two centuries.

Vesalius had attributed the tracing of the first figures to a certain Fleming, but at Fabrica he did not trust anyone, and the identity of the artist or artists who collaborated in his work has been the subject of great controversy, which has been heightened by the question of who is more. important, whether the artist or the anatomist. The latter was an irrelevant discussion, since it is obvious that illustrations are important precisely because they bring together a combination of art and science, a collaboration between the artist and the anatomist. The figures of the Factory imply so much anatomical knowledge that Vesalius had to participate in the preparation of drawings, although the degree of refinement and knowledge of new drawing techniques, also for Renaissance artists, also excludes that he was solely responsible. To this day it is debated whether Jan Stephan van Calcar (1499-1456 / 50), who made the first figures and worked at Titian's studio in nearby Venice, was the artist. In any case, a solution had been found in the search for a pictorial expression appropriate to natural phenomena.

In the seventeenth century, remarkable discoveries were made in the field of human anatomy and physiology. Francis Glisson (1597-1677) described in detail the liver, stomach and intestines. Although his views on biology are basically Aristotelian, he also had modern conceptions, such as those concerning nerve impulses responsible for gallbladder emptying.

Thomas Wharton (1614-1673) went a long way in overcoming the old, common idea that the brain was a mucus secreting gland (no doubt he still believed that tears originated there). Wharton described the differential characteristics of the digestive, lymphatic and sexual glands. The evacuation conduit of the submandibular salivary gland is known as the Wharton conduit. An important contribution was to distinguish between internal secretion glands (now called endocrine), whose product falls into the blood, and external secretion glands (exocrine), which discharge into the cavities.

Niels Steenson, in 1611, established the difference between this type of gland and the lymph nodes (which were called glands although not part of the system). I thought the tears came from the brain. The new conception of organism transport systems that has been gained through the contributions of many researchers has helped to solve the errors of galenic physiology concerning blood production.

Gasparo Aselli (1581-1626) found that after ingesting a large amount of food, a dog's peritoneum and intestines were covered with white fibers that, when sectioned, spilled an off-white liquid. These were the kiliferous capillaries. Until Harvey's time, breathing was thought to stimulate the heart to produce vital spirits in the right ventricle. Harvey, however, demonstrated that the blood in the lungs changed from venous to arterial, but did not know the basis of this transformation. The explanation of respiratory function took many years, but during the seventeenth century important steps were taken to clarify it.

Robert Hook (1635-1703) demonstrated that an animal could survive also without lung movement if we inflated air into the lungs.

Richard Lower (1631-1691) was the first to perform direct blood transfusion, demonstrating the color difference between arterial and venous blood, which was due to the air in the lungs.

John Mayow (1640-1679) stated that the redness of venous blood was due to the extraction of some substance from the air. He came to the conclusion that the breathing process was no more than an exchange of air and blood gases; he gave in to the nitroaeric spirit and gained the vapors produced by the blood.

In 1664 Thomas Willis (1621-1675) published De Anatomi Cerebri (illustrated by Christopher Wren and Richard Lower), arguably the most detailed compendium on the nervous system. His anatomical studies linked his name to the circle of the arteries of the base of the brain, the eleventh cranial pair, and also to a certain type of deafness. However, his obsession with locating mental processes at the anatomical level led him to mistaken conclusions; among them, that the brain controlled the movements of the heart, lungs, stomach, and intestines, and that the corpus callosum was a matter of imagination.

From then on, the development of anatomy accelerated. Berengario da Carpi studied the appendix and the thymus, and Bartolomeu Eustáquio the ear canals. The new Renaissance anatomy required the revision of science. Padua-educated Englishman William Harvey combined Italian anatomical tradition with experimental science born in England. His book about it, published in 1628, deals with anatomy and physiology. Alongside dissection problems and description of isolated organs, he studies the mechanics of blood circulation, comparing the human body to a hydraulic machine. The microscope improvement (by Leeuwenhoek) helped Marcello Malpighi prove Harvey's theory of blood circulation and also discover the most intimate structure of many organs. Thus, the microscopic study of anatomy was introduced. Gabriele Aselli highlighted the lymphatic vessels; Bernardino Genga then spoke of "surgical anatomy."

In the eighteenth and nineteenth centuries, the detailed study of operative techniques led to the subdivision of anatomy, with much emphasis on topographic anatomy. The anatomical-clinical study of the corpse, as the safest way to study the changes caused by the disease, was introduced by Giovan Battista Morgani. Pathological anatomy emerged, which allowed for great discoveries in the field of cellular pathology by Rudolf Virchow and the agents responsible for infectious diseases by Pasteur and Koch.

Recently, anatomy has become submicroscopic. Physiology, biochemistry, electron and positronic microscopy, X-ray diffraction techniques applied to the study of cells are describing their intimate structures at the molecular level.

Nowadays there is the possibility of studying anatomy even in living people through imaging techniques such as radiography, endoscopy, angiography, axial computed tomography, positron emission tomography, nuclear magnetic resonance imaging, ultrasound imaging. , thermography and others.