Chapter 11 - Cutting in Biology, Palaeontology and Medicine

Abstract

Cutting has been used as a means to an end in various areas of biological and medical research. Most surgery cuts are only so far into the body in order to explore what is there, or to remove, repair or replace organs. Dissection of dead bodies opens up the interior for inspection for teaching anatomy, to establish causes of unexpected death of healthy animals, and for forensic purposes. The excision of a piece of tissue from a living body for diagnostic study (biopsy) can be performed in various ways, of which punch biopsy is insertion of a hollow punch to separate a cylindrical column of tissue that is then stretched away from the surface and snipped off. The instrumented microtome can be employed as a “mechanical microscope” in pathology. In surgery, and dissection, efficient cutting is required with low forces and “clean” cuts; the victim of a stabbing attack by knife would rather have inefficient cutting, but the mechanics are the same whether the blade is wielded benignly or malignly. Amputation cuts limbs off completely, taking place either deliberately by a surgeon, or in accidents or war. The removal of the whole or part of a diseased or malfunctioning limb, or the trimming of the stump of a limb that has been accidentally severed, is one of the oldest surgical operations.