Andreas Vesalius, the Reformer of Anatomy

by James Moores Ball

GALEN

Claudius Galenus, the celebrated Roman physician whose writings were for centuries accepted as authority and whose reputation was second only to that of Hippocrates, was obliged to base his anatomical treatises largely upon the dissection of the lower animals. He advised his pupils to visit Alexandria, where he had studied, in order that they might examine the human skeleton. He complained that the physicians of his time—in the reign of Marcus Aurelius—had entirely neglected anatomical knowledge and had degenerated into mere sophists. He appreciated the importance of anatomy, particularly to a surgeon who is called upon to treat wounds and injuries. Hence he has endeavored in the four books, De Anatomicis Administrationibus, to cover this part of anatomy as exhaustively as possible.

Galen’s voluminous writings form a precious monument of ancient medicine. The works of the Alexandrian anatomists having been destroyed, we know of their labors chiefly from what Galen has said of them. His treatises show a remarkable familiarity with practical anatomy, although his dissections were made upon the lower animals. Galen’s knowledge of osteology was extensive. He described the bones of the skull, the cranial sutures, and the essential features of the malar, maxillary, ethmoid and sphenoid bones. He divided the vertebrae into cervical, dorsal and lumbar classes. He knew that both arteries and veins were blood-carrying vessels; he described the valves of the heart, and recognized this organ as the source of pulsation. He erroneously taught that the interventricular septum presents foramina through which the two kinds of blood become mixed.

In myology Galen made numerous advances. “Previous to his investigations”, says Fisher[6] “much confusion existed as to what constituted a single muscle; he adopted the general rule of considering each bundle of fibers that terminates in an independent tendon to be one muscle. He was the first to describe and give names to the platysma myoides, the sterno- and thyro-hyoides, and the popliteal. He described the six muscles of the eye, two muscles of the eyelids, and four pairs of muscles of the lower jaw—the temporal to raise, the masseter to draw to one side, and two depressors, corresponding to the digastric and internal pterygoid muscles. He described also the brachialis anticus, the biceps flexor cubiti, the sphincter and levator ani, and the straight and oblique muscles of the abdomen. In short, he described the greater portion of the muscles of the body, his treatise differing chiefly from a modern one in the minute account of these organs and in the omission of some of the smaller muscles.” Galen studied the brain and named the corpus callosum, the septum lucidum, the corpora quadrigemina and the fornix; but erroneously stated that the nerves of sensation arise from the brain, and those of motion from the spinal cord. He denied the decussation of the optic nerves. He described the pneumogastric and sympathetic nerves; seven pairs of cerebral and thirty pairs of spinal nerves; and claimed the discovery of the ganglia of the nervous system. He located the seat of the soul in the brain, which also is the source of the rational mind; the heart to him was the source of courage and of anger, and the liver was the seat of desire. Many of Galen’s anatomical statements show that he derived his knowledge from comparative dissections.

The Galenic era was followed by that long period of ignorance, of slumber and of inaction which is justly known as the Dark Ages. While a few Greek and Arab writers, who came after Galen, contributed to the literature of medicine and surgery, they did nothing for anatomy. After the end of the fifth century even the works of Galen were forgotten. At this period, when medicine was chiefly in the hands of the Jews, the Arabs and the bigoted clergy, nothing was done for science or for art. The whole influence of Christianity was exerted against the schools of philosophy. Illustrious apostles of the Church pronounced anathemas against the reading of the ancient classics;[7] and eminent ecclesiastics regarded disease as a divine penalty or as an invaluable aid to saintly advancement. Art and anatomy were practically forgotten. Their Renaissance occurred almost simultaneously.

During the period from the seventh to the fourteenth centuries the school of Salernum was for medicine what Bologna became for law and Paris for philosophy. Here, for eight hundred years, medicine was taught to thousands of students and the impress of the profession was so potent that the city called itself Civitas Hippocratica, and thus its seals were stamped. Here medical diplomas were first issued to waiting students who took a sacred oath to serve the poor without pay. Here with a book in his hand, a ring on his finger and a laurel wreath on his head, the candidate was kissed by each professor and was told to start upon his way. Here women were professors and vied with men in spreading the doctrines of our art.

For a period of several hundred years anatomy was taught at Salernum from dissections made upon pigs. Copho, one of the Salernian professors of the early part of the twelfth century, wrote a treatise, Anatomia Porci, which gives minute directions regarding the manner in which the animal is to be dissected. Another anatomical work of later date, written by a member of the Salernian faculty, is entitled Demonstratio Anatomica; it also deals only with comparative anatomy. In the thirteenth century (A. D. 1231) Frederick II., Emperor of Germany and King of the Two Sicilies, and the author of a treatise which contained a complete anatomy of the falcon, decreed that a human body should be anatomized at Salernum at least once in five years. Physicians and surgeons of the kingdom were required to be present at the dissection. So far as is known, no record has been kept of these demonstrations. Creditable as was this anatomic decree, the great Hohenstaufen in other respects was not free from the errors of his age. A firm believer in Medicina Astrologica, he did not decide upon any undertaking until the stars had been consulted.

It was not alone at Salernum that dissection was legalized in the thirteenth century. A document of the year 1308, of the Maggiore Consiglio of Venice, shows that a medical college located in that city was authorized to dissect a body once a year. This, and other isolated examples, indicate that the time was approaching when anatomy should be taught from human dissections. The credit of reinaugurating the teaching of this useful department of science belongs to Mondino dei Luzzi of Bologna.