The word ‘anatomy’ derives from the Greek ana (up) and tome (a cutting) — hence ‘dissection’ — and it can be defined as the science of the structure of a body learned by dissection. The word can thus be applied to any structure, and we can talk about the anatomy of a plant, an insect, or even a machine, but here the term will be restricted to the structure of the human being.
Since earliest times, man may have been curious about the inner structure and workings of his body. Certainly the ancient Egyptians, in performing mummification, which involved preliminary removal of the viscera, would have gained considerable information about the organs of the chest and abdomen. However, the practitioners of this art were not medical, and there is little evidence that the doctors of those times derived any knowledge from this potentially rich source of anatomical material. The first recorded school of anatomy, where dissection of the human body was performed, was in Alexandria, and it flourished between the first century bc and the second century ad. Here two Greeks, Herophilus and Erasistratus, were celebrated for their experience of anatomy acquired by the dissection of condemned criminals, and they described many structures of the human body. Herophilus recognized the brain as the central organ of the nervous system and the seat of intelligence, thus reversing the view of Aristotle, the Greek philosopher, of the primacy of the heart. Erasistratus observed the convolutions of the brain, noted that they were more marked in man than in lower animals, and associated this complexity with the higher intelligence of man. He also described the main parts of the brain, its coverings, and its cavities, the ventricles.
The most celebrated anatomist of the ancient world was undoubtedly Galen (129-216 ad). Born in Pergamon in Asia Minor, he studied in Smyrna and Alexandria before settling in Rome. He studied the human skeleton in Alexandria, but by then human dissection had virtually ceased, and much of his anatomy was based on animal studies.
Although Galen made many contributions to the subject, his work on bones and muscles being particularly good, and although many of the anatomical terms still in use today have their roots in his work, he also made errors and misinterpretations in his findings. In spite of this, his writings were regarded as definitive and beyond criticism over the next 1300 years. As a simple example, he described the kidneys as being lobulated, as they are in cattle, when the most casual glance would have shown that they are smooth in man. His statement that blood passed through pores between the left and right side of the heart again could have been refuted by simple observation. To make matters worse, continued copying of his writings and translations from one language to another led to further mistakes and faults creeping into his texts.
During the Middle Ages, human dissection was frowned upon by the Church. In the late fifteenth and early sixteenth centuries, a revival of learning and, with it, of anatomical observation took place, especially in Italy and more particularly in the University of Padua. It was there that a revolution in anatomy took place with the publication, in 1543, by Andreas Vesalius, then aged only 28, of his book De Fabrica Corporis Humani (The Structure of the Human Body). This was based on his personal observations of his own human dissections, and of studies of the human skeleton. It contained magnificent illustrations, taken directly from his dissections, which could be used today in any modern textbook of anatomy.
Over the next centuries dissection of the human body became a standard part of the training of medical students. Indeed, it provided more or less the only scientific subject in the curriculum. However, because of religious and social attitudes surrounding the acquisition of bodies, and because of the unpleasant nature of dissection on unpreserved and often decomposing material, both anatomy and practitioners followed a somewhat chequered course. Anatomies were usually made in winter months, when the process of putrefaction was delayed, and the timing in England was also made to correspond with the assizes, when the bodies of executed criminals would be available. The legitimate sources of bodies — executed criminals and unclaimed corpses of paupers — were often inadequate for the increasing numbers of medical schools and of medical students. In Britain in particular, there was the scandal of the grave robbers (or ‘resurrectionists’ as they were called), who would dig up a body shortly after burial and sell it to an anatomy school. Relatives would sit up, armed, at night to protect the grave, or secure the graves with iron cages known as ‘mort-safes’. Sometimes, indeed, because of the chronic shortage of bodies, criminals would resort to murder to obtain their material, as in the infamous case of Burke and Hare in Edinburgh, who committed no less than 16 murders. Hare turned King's evidence, but Burke was hanged and afterwards publicly dissected. The scandal of this case undoubtedly led to the Anatomy Act of 1832, which licensed premises for dissection and made legal the provision of bodies from workhouses or elsewhere which were unclaimed. The anatomy school was responsible for the subsequent burial or cremation of the body according to the religion of the deceased. These regulations have gradually been replaced by the bequests of individuals of their bodies for anatomical purposes after death so that today, in the UK, virtually all bodies are received at anatomy departments by these means.
The techniques of anatomical studies were improved by the injection of coloured materials into blood vessels and lymphatics, and by methods of embalming and preserving the body. Formalin, discovered in 1868 by Von Hoffman, rapidly replaced other preservative agents, and remains the basis of modern preservation methods.
The development of simple microscopes in the seventeenth century founded the important science of microscopic anatomy. A pioneer in this field was Malpighi, whose extensive studies demonstrated the blood capillaries, thus finally establishing the anatomical basis of the circulation of the blood. He also described red blood corpuscles, and the structure of the skin and of many other tissues. The modern achromatic compound microscope was invented in 1878, and it was this instrument that added the extra dimension of the microscopic study of tissues to anatomical teaching.
With the advent of anaesthesia in 1846, and the introduction of antiseptic surgery as a result of the work of Lister in 1867, the vistas of surgery were greatly increased and, with them, the importance of a detailed knowledge of anatomy to the surgeon. To most students, however, anatomical teaching was something of a sterile test of memory, with emphasis on exact topographical details of the finer ramifications of nerves and blood vessels. In the twentieth century, particularly in its second half, the subject of anatomy became much wider and of a more practical nature. It is true to say that there is little interest today in ‘pure’ topographical anatomy. The detailed mapping of the human body is now fully documented and is to be found in the major textbooks. Indeed, the name of Gray's Anatomy, the standard text, has passed into popular parlance. However, in its various sub-divisions, the subject is thriving and the most important of these need some separate descriptions.
Topographic anatomy
In this, the body is studied by regions rather than by organs. This is of importance to the surgeon who exposes different planes after the skin incision and who, of course, must be perfectly familiar with structures as he explores the limbs and body cavities. Once the sole preserve of the surgeon, this field has acquired immense significance today for the radiologist (see below). In this respect cross-sectional topographic anatomy has come into its own.
Endoscopic anatomy
With the development of fibreoptic instruments, the body's tubes and cavities are now being explored in life. The detailed anatomy, for example, of the bronchial tree as seen through the bronchoscope is now of great importance. The introduction of laparoscopic and thoracoscopic instruments to explore and operate in the abdomen and thorax respectively has also opened new vistas as surgeons require to learn their anatomical landmarks through these approaches.
Surface (living) anatomy
From the practical point of view, every medical practitioner needs to know the detailed structure of the tissues beneath the skin of his patient. This forms an important part of the teaching of medical students, who can practise on themselves the identification of bones, landmarks, muscles, and arterial pulses; the palpation of normal structures through the intact skin; and the range of movement of the joints.
Radiological and imaging anatomy
The discovery by Röntgen of X-rays a century ago opened new vistas of anatomical study. This was enhanced by the development of radiological techniques to outline viscera, for example by injecting radio-opaque solutions into blood vessels (angiography) or by swallowing barium paste in order to demonstrate the oesophagus and stomach. More recently, other imaging techniques, which include ultrasonography, computerized tomography, and, in particular, magnetic resonance imaging, have provided unrivalled information of three-dimensional anatomy in the living body. Indeed, today, the radiologist must possess a detailed knowledge of anatomy that certainly rivals that of his surgical colleagues.
Embryological anatomy
The complex changes in the growing fetus are studied because much of adult anatomy can only be understood by appreciating its prenatal development. More and more has been learned about the underlying causes of the numerous congenital abnormalities that may arise as aberrations of normal development.
Microscopic anatomy
is of fundamental importance in the understanding of pathological changes, and has advanced with the introduction of electron microscopy, which enables the finest details of the cells to be studied at an ultramicroscopic magnification of several thousands.
Kinesiology,
the study of joint and limb movement, has developed into a subject of immense importance, together with biomechanics and orthotics (the study and use of artificial limbs). Here, research has an immediate application in orthopaedic practice, for the study of joint prostheses, the measurement of forces acting on the skeleton, and choosing the strength of materials utilized in reconstructive surgery; also for the analysis of the causes of failures of artificial joint implants, or of the materials used in internal fixation of fractures.
Neuroanatomy,
the study of the brain, spinal cord, and nerves, forms an important part of the battery of approaches needed for neurobiological exploration, which today is complemented by physiology, pharmacology, molecular biology, and dynamic whole brain imaging.
All these topics are of obvious importance in the various expanding fields of medicine, but anatomy also impinges on other sciences. Examples are comparative anatomy — the comparison of structures in different animals and species; palaeoanatomy — the study of ancient remains — mainly, of course, of bones; and physical anthropology — the study of the different human races.
A recent development has been the appearance of a complete, sectioned human body appearing on the World Wide Web. The Visible Human Project presents transverse CT, MRI and cryosection images of two complete human cadavers, one male and one female, at an average of 1 mm intervals. These allow three-dimensional constructions to be ‘visualized’ from any angle on the computer screen.
Anatomy is thus a subject which encompasses a great variety of endeavours characterized by the study of the organization of the human body, and which impinges on many other sciences. In teaching anatomy to medical students, dissection of the cadaver remains fundamental, but the student also studies living, imaging, microscopic, and embryological anatomy. Anatomy forms an essential part of the scientific basis of medicine. All those concerned with disorders of the human body must start from a background of knowledge of its normal macroscopic and microscopic structure.
— Harold Ellis
See also dissection; Gray, Henry.
