Damage that occurs as a result of squeezing or hitting any, even a small, area of the object, is usually designated as hurt, that is, caused by the action of a blunt solid object. Such injuries in forensic practice are most common.
Despite the diversity of such injuries, they are based on a common mechanism by which the anatomical integrity of the tissues of an organ or its function is disrupted. Both upon impact and compression (compression), dull objects (more or less sharply) produce a squeezing effect at the expense of their surface. Usually, at the same time, the tissues are not separated, and if this happens, the already-kneaded soft tissues are separated. The direction of the external impact, the surface properties of the traumatic object and the magnitude of the kinetic energy are factors that largely determine the morphological features of the damage. Among the many objects that are considered injuries as injury by a blunt solid object, there are parts of moving vehicles, various objects having a flat or uneven surface (stone, stick), as well as parts of the human body: fist, leg, head, etc.
The action of the damaging object at an angle of 90 ° to the surface of the human body, depending on the kinetic energy and impact area, can cause various damages. The more the impacting surface, the less (all other things being equal) the trauma at the impact site is expressed. Phenomena of shaking the body come to the fore. There are breaks parenchymatous organs (liver, kidney, spleen). There are even tears of organs such as the heart, lungs, and their displacement, which is observed in traffic injuries or falls from a great height.
With a decrease in the area of the damaging object (in the place of impact.) Damage increases, since the kinetic energy is concentrated on a small surface. Depending on the properties of the striking part of the object, damage occurs (bruises, wounds, fractures) of one form or another.