Anatomy is often simply defined as the science concerned with the study of the structure of biological organisms. Indeed, such a definition is typical of most dictionaries. Since NetAnatomy focuses on human anatomy, the definition may be refined to a study of the structure of the human body. In fact, many anatomists would likely not accept such a definition because of its lack of reference to function. Within all biological organisms, and indeed most mechanical devices of far less complexity than the human body, structure and function are intimately related. Thus, a more accurate definition of contemporary human anatomy would be the study of structure and its relation to function in the human body.
The term anatomy itself has a Greek origin that means “to cut up” or “to dissect”. While the first scientifically-based anatomical studies (credited to Vesalius, a 16th century Flemish anatomist, physician, and artist) were based on observations with the unaided eye on dissected cadavers, contemporary human anatomy includes additional modes of observation and emphases. This in turn has contributed to subdivisions or ‘subdisciplines’ within the broader field of anatomy. It is now common to precede the word anatomy with an adjective that defines the mode of observation, e.g., gross anatomy or microscopic anatomy, that defines a particular field of anatomical interest, e.g., developmental anatomy or neuroanatomy, or that defines the approach one takes in the study of the body, e.g., regional anatomy (by body regions) or systemic anatomy (by biological systems). Additional terms are particularly common to medicine, e.g., radiographic anatomy, clinical anatomy, etc. A true appreciation for the anatomy of the human body encompasses study in many if not all of the anatomical subdivisions. The more common subdivisions are as follows:
• Applied Anatomy – the practical application of anatomy, typically in a diagnostic or therapeutic clinical procedure, e.g., the application of anatomical knowledge during the performance of a physical examination.
• Clinical Anatomy – the study of anatomy that is most relevant to the practice of medicine.
• Comparative Anatomy – the study of the anatomies of different organisms, drawing contrasts and similarities between the structure and function of the anatomies.
• Cross-Sectional Anatomy – anatomy viewed in the transverse (syn. horizontal) plane of the body.
• Developmental Anatomy – the study of the biological processes that extend from fertilization to the formation of the adult anatomy. Embryology is a subdivision of developmental anatomy that is concerned exclusively with the developmental processes that occur prior to birth.
• Gross Anatomy (syn. Macroscopic Anatomy) – the study of anatomy with the unaided eye, essentially visual observation without the use of significant magnifying technologies; classically undertaken using dissected cadavers.
• Microscopic Anatomy (syn. Histology) – the study of anatomy with the aid of the light microscope; contemporary microscopic anatomy would also include observation using transmission and scanning electron microscopes that provide subcellular observations.
• Neuroanatomy – the study of the central and peripheral nervous systems.
• Radiographic Anatomy (syn. Radiological Anatomy) – the study of anatomy as observed with imaging techniques that are derived from the diagnostic and therapeutic tools of the clinical field of radiology; within clinical practice commonly includes plain film radiography (with or without contrast materials), magnetic resonance imagery (MRI), computed tomography (CT), and ultrasonography.
• Regional Anatomy – the study of anatomy by regional parts of the body, e.g., thorax, lower limb, etc. Under this mode of study all of the biological systems, e.g., skeletal, circulatory, etc. located within a particular body region are simultaneously studied with an emphasis on the interrelation of the systems and their regional function.
• Surface Anatomy – anatomy as it occurs on and projects to the external surface of the body; particularly important in the performance of diagnostic and therapeutic clinical procedures. Surface anatomy includes both that which can be directly palpated on the body surface, e.g., underlying bone or muscle, as well as that which cannot be directly palpated, e.g., a deeply positioned organ. In the latter, knowledge of the surface projection of the organ contributes to applied anatomy, e.g., positioning a stethoscope on the chest wall so as to maximize the audition of heart sounds.
• Surgical Anatomy – the application and study of anatomy as it relates to surgery, which itself (in a very broad sense) may be defined as the diagnostic or therapeutic manipulation of anatomy.
• Systemic Anatomy – the study of anatomy by biological systems, e.g., skeletal system, muscular system, circulatory system, etc. In this mode of study a single biological system is studied concurrently across all body regions.