Human Anatomy: Early History

Dr. T.V.N. Persaud

Professor Emeritus, Department of Human Anatomy and Cell Science, University of Manitoba


 

From fossil discoveries that were made in Africa, we know that a bipedal human-like creature emerged more than six million years ago. Not long after, before the old stone age, he began to create such astonishing works of art which will continue to fascinate us. Among the earliest are the remarkable cave pictures that were done during the Ice and Stone Ages. For example, in France and Spain, life-size drawings of man and large mammals, painted on the walls and ceiling of damp caves, have survived more than a thousand of years. What is the significance of these pictures? Art historians believe that these paleolithic drawings were done as part of some magical rituals, or might have evolved from hunting stories and myths.

Even more fascinating is the silhouette of more than 200 human hands depicted in a cave in Gargas, Southern France. Most of the hands revealed mutilation of one or more fingers, and only 10 appeared to be complete. The remaining hands have not been well preserved to determine whether they are intact or mutilated. The age of the pictures has been estimated from a period between 60,000 and 40,000 B.C., but the people it originated from, and the reasons for the mutilation, and for depicting the hands, remain a mystery.

Among the earliest sculptures of the human form is this paleolithic limestone figurine, known as the Venus of Willendorf. It is about 4.5 inches high and is dated from between 25,000 and 30,000 B.C. The head is almost faceless, but the pendulous breasts and a protuberant abdomen are symbolic of a fertility goddess. Similar carvings have been discovered in other parts of the world.

We can only speculate as to when man first peered into the interior of the human body - might it have been from some terrible hunting accident or from such injuries inflicted in battle that ripped open the body surface? From archaeological evidence we know for certain that about 10,000-5,000 B.C., prehistoric man purposefully bore open a human skull and the patient survived! By the New Stone Age period (3000-2000 B.C.), trephination of the skull was widely practiced in Western Europe, as well as in South America and Asia. The ancients believed that evil spirits can live in the head, and most likely trephination was carried out in cases of epilepsy, mental illness, or severe headaches. The hole that was drilled in the skull allowed the evil spirits to escape, so much so that leaders of the clan would have a few holes drilled in their skull so that evil vapors could continuously escape. Of the 10,000 well-preserved pre-Inca mummies discovered in Peru, more than 500 showed evidence of a trephination, some on several occasions, all over the cranium and varying in size. It has been estimated that at least 50% survived the procedure. These early neurosurgeons would have seen the meninges, superior longitudinal sinus, and the surface of the brain.

In ancient Mesopotamia, temple priests predicted the future and interpreted natural events from observations made of the internal organs of sacrificial animals. The priests made clay models of the liver and lungs of the sheep and different parts were carefully marked out with appropriate cuneiform scripts. These were often used for instructing their disciplines.

The oldest anatomical records we know of are the fragments in the medical section of the Egyptian papyruses, especially the Ebers papyrus, which probably began earlier than 3000 BC. Diseases of the eyes (cataracts), hemorrhoids, rectal prolapse, intestinal parasites, abdominal pain, fractures, and various urological conditions are mentioned. Some knowledge of the human viscera was first obtained in ancient Egypt because of the practice of embalming and mummification, which the Ancient Egyptians believed ensured an everlasting life. The brain, lungs, liver, and intestines were removed and placed in four urns or canopic jars. The heart was left undisturbed in the body because it was considered to be the seat of the soul.

In India, long before the Aryan invasion from the Northwest in 1500 BC, an ancient civilization flourished in the Indus valley with orderly laid-out settlements, baths, advanced social organization, and good sanitation. The classic Hindu medical manuscript Susruta Samhita was composed in AD 200. It contains large sections devoted to surgery, description of more than 100 operations and the instruments used, and an extensive materia medica of medicinal plants, as well as specific instructions for dissecting the human body. A knowledge of human anatomy would have been required for many of the surgical procedures recorded in this manuscript. These included cataract extraction, repair of torn ear lobes and cleft lip, removal of stones from the bladder, suturing of the intestines, tonsillectomy, and Caesarian section. Plastic surgery on the nose probably had its beginnings from this era. Because the nose was cut off as a punishment for adultery rhinoplasty was carried out! Two of the great names from this period are the physicians Charaka and Susruta. Recognizing the importance of human anatomy for the practice of surgery Susruta dissected the body in spite of religious laws which prohibited contact with the deceased other than for the purpose of cremation.

The Greeks questioned previous ideas about the world and produced new explanations - not just in medicine and science but in many other areas of knowledge. About 500 B.C., Alcmaeon of Croton, a contemporary of the mathematician Pythagoras, pursued some anatomical studies. From the fragments that have survived from his work, we know that he dissected animals with the sole purpose of understanding their anatomy. Alcmaeon discovered the optic nerves and the pharyngotympanic tubes, which was re-discovered by Eustachius in the sixteenth century. Alcmaeon asserted that the brain, not the heart, was the organ responsible for intelligence. Sleep he attributed to a transient suppression of cerebral blood flow which led to death when it became permanent. He knew that the eyes were connected to the brain and that light entering the eyes was essential for sight.

Hippocrates (460-377 BC) of Cos, the father of Western medicine, challenged the old superstitious beliefs of diseases, and put forward a concept that illness might have “natural” causes and cures. Hippocrates postulated that anatomy is the foundation of medicine, but at the same time he believed that one could learn sufficient anatomy by observing wounds and human bones, without the unpleasant task of dissecting corpses. In the Hippocratic Corpus we find a fairly good account of bones, especially of the skull, including the sutures, and of the joints in the body. One should bear in mind that Hippocrates humoral theory, which postulated that various diseases were the result of dyscrasias of four elemental body humors, could by it’s very nature not have stimulated an interest in anatomy.

Aristotle (384 - 322 BC), the greatest natural philosopher from this era, was considered by Charles Darwin as the world’s greatest natural scientist. Aristotle studied animals which he also dissected, but his knowledge of the human body was based on speculative ideas. He remarked that “ the internal parts are not so well known, and those of the human bodies are the least known, So that in order to explain them we must compare them with the same parts of those animals which are most nearly allied.” Aristotle laid the foundation of comparative anatomy and established embryology on a scientific course by his observations of the chick embryo. His preformation theory of embryonic development survived in one form or the other until the 17th century.

About this period, in a distant corner of the Greek empire - at the medical school in Alexandria, Egypt, the human body was purposefully dissected in order to reveal its internal structure. Here, Herophilus (c. 300BC-) and Erasistratus (c. 250BC) made many anatomical discoveries through routine dissection of more than 600 cadavers, and allegedly condemned criminals. The Roman scholar Celsus (c. 30 BC-45 AD) wrote that the criminals were obtained “for dissection alive, and contemplated, even while they breathed, those parts which nature had before concealed.” According to the historian Tertullian as many as 600 living criminals were vivisected, and even fetuses were removed from the womb. He described Herophilus as "that butcher who cut up innumerable corpses in order to investigate nature and who hated mankind for the sake of knowledge."

Herophilus is often called the “father of anatomy.” All of his writings, including his book On Anatomy have been destroyed. Herophilus described the delicate arachnoid membranes of the cerebral ventricles, the confluence of venous sinuses near the internal occipital protuberance which bears his name, the lacteals, coverings of the eye, liver, uterus, epididymis, and many other structures. The name “duodenum” is attributed to him. Herophilus differentiated nerves of sensation from those associated with voluntary movement, and he knew that damage of the latter led to paralysis.

The younger Erasistratus was more a physiologist. He formulated a "pneumatic theory" and regarded the heart as a pump. Erasistratus described the auricles of the heart, cardiac valves, blood vessels, including the aorta, pulmonary artery and veins, hepatic arteries and veins, renal vessels, superior and inferior vena cava, and the azygous vein. Erasistratus recognized the function of the trachea. He also differentiated the cerebrum from the cerebellum, described the cerebral convolutions, ventricles, and meninges.

Alexandria began its decline with the Roman invasion in 48 B.C., climaxed by the burning of its famous library of 700,000 volumes. At that time the library housed all the learning of the ancient World. Egypt became part of the Roman empire, and medicine was still nurtured by Greek and other scholars but culturally in a Roman environment. Human dissection was forbidden or not encouraged - a situation that lasted until the late middle ages. Like in some medical schools today, it was declared unnecessary in the training of physicians. The greatest figure of the time was the physician Claudius Galen (131-201 AD).

Claudius Galen (AD 131-192). Galen was not only a great physician but also a celebrated anatomist. Galen’s work was recorded into numerous complex treatises covering all conceivable aspects of man’s knowledge. He even published a guide to his writings, entitled On his own Books. Galen wrote more than 130 medical treatises, of which 80 have survived, and these classic works became the unquestionable repository of medical knowledge for more than a thousand years after his death. Galen must have gained valuable insight from treating the wounds of the gladiators, but many of his anatomical descriptions were wrong because of his reliance on animal dissection. Galen made many important contributions to medicine. He accurately described the consequences of spinal cord damage at different levels. He observed loss of sensation and paralysis of all muscles supplied by nerves originating from the spinal cord following complete resection below that level. Galen showed that in addition to the diaphragm other muscles were involved in respiration. Moreover, he left us a detailed description of the origin and course of the phrenic nerve, and his discovery of the recurrent laryngeal nerve led him to understand something of voice production in the larynx.

Galen described a rete mirabile (a marvelous network) at the base of the human brain which does not exist in man but in hoofed animals. According to Galen, this was the seat of man’s “animal spirit” which later became transformed into “vital spirit.” He also misrepresented the shape of the human heart, branches from the aortic arch, the location of the kidneys, the shape of the liver, as well as other anatomical structures.

How influential were the teachings of Galen? In 1559, The Royal College of Physicians of London made one of its members, Dr. John Geynes, retract his statements that there were 22 inaccurate passages in the works of Galen. In 1595, Dr. Edward Jordan, a medical graduate of the University of Padua, was required to read five of Galen’s works before being admitted to Fellowship, and in the same year a Dr. Thomas Rawlins was failed by the College because his knowledge of Galen was inadequate.

It is tempting to believe that Galen ushered a long and dark period in the history of medicine, including anatomy, but one should take into consideration the dismal era during which he lived. For a fitting tribute to Galen, I would like to cite the remarks of a great medical scholar, linguist, and Galen translator - Hunain ibn Ishaq of Baghdad (A.D. 809-873), who upon completing his translation of Galen’s 15th book commented:

this excellent, outstanding work which is one of the compositions of a man who performed marvelously, and revealed extraordinary things, the master of the earlier surgeons, and the lord of the more recent savants, whose efforts in the practice of medicine have been unequaled by any of the prominent since the days of the great Hippocrates - I mean Galen. May God Almighty be merciful to him!

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