Damage from blunt objects is the mechanism of their formation. Damage from blunt objects. Damage from a fall

rice. 1-136

Damage to tissues or organs occurs mainly due to physical external influences, among which the first place belongs to mechanical factors. Mechanical damage occurs as a result of contact of a moving

an object with a human body or when a moving body comes into contact with an object.

The process of sequential exposure of the human body to a moving traumatic object that contributes to the formation of damage is called the mechanism of injury.

Injuries from hard blunt objects are the most common type of mechanical injury. They account for 32% of all injuries in fatal injuries caused by mechanical factors.

Objects that cause damage are extremely diverse in shape, size, weight, characteristics of the impact surface (flat, smooth, uneven, rough, rounded, etc.), material properties, number and location of edges (faces), etc. Therefore, arising from their damage actions are extremely diverse and polymorphic. The concept of “hard blunt objects” also includes parts of the human and animal body used to cause damage (fist, knee, teeth, foot, claws, etc.).

The mechanism of injury caused by hard blunt objects is caused by four types of traumatic effects - impact, compression (compression), friction and stretching of tissues. During impact and compression, damage occurs both from direct and indirect effects. In the first case, local (contact) damage occurs at the site of direct application of force. The indirect action of impact (compression) leads to flexion, extension, torsion, displacement (shock), hydro- and aerodynamic changes that cause damage to various parts and tissues of a person. As a result of the indirect action of the blow (compression), numerous different types of damage occur, which are always located far from the place of primary application of the traumatic force, i.e. are distant. During friction, damage is formed as a result of tissue shear at the site of direct application of force (local). When the body or its parts are stretched, the damage resulting from tissue overstretching is always located far from the place of exposure to the traumatic force. The consequence of these traumatic effects is a variety of damage to soft tissues, bones and internal organs. The type and nature of damage depend on the energy and direction of the force, mass, area and surface features of the impacting object, the angle of its contact, etc. In damaged tissues and organs, contours (in whole or in part) and details of the contacting surface of the object, its particles in the form of overlays can be reflected and inclusions, which is important for group, species and individual identification of the instrument of injury.

Soft tissue injuries include abrasions, hemorrhages and wounds. The mechanism of these injuries depends on many factors, one of which is the direction of action of the traumatic force. The sequence of changes in soft tissues under the influence of centripetal force: first, the tissue is flattened, then compressed, crushed, stretched and torn. When exposed to centrifugal force, the tissue is displaced, flattened, stretched, stretched, torn and peeled off.

An abrasion is a violation of the integrity of the skin and mucous membrane caused by a mechanical factor (impact, friction). Abrasions can be superficial and deep, small and large in size, of different shapes - linear, semilunar, round, oval, etc. An abrasion can reflect not only the surface of an object in contact with the skin, but also the direction of its sliding along the skin.

Hemorrhage occurs when soft tissue is struck or compressed due to rupture of underlying blood vessels. Blood pours into the surrounding tissues and permeates them, forming a macroscopically visible blood clot (bruise) on the skin. Ruptures of blood vessels are most often the result of injury, but can also be a manifestation of some pathological process. Hemorrhages can be local and distant, superficial, deep and very deep, and can appear early, late or very late. They are quite varied in shape: round, oval, rectangular, etc. Often, hemorrhages on the skin reflect the shape and size of the damaging object (chain, belt buckle, etc.). By changing the color of the hemorrhage, one can roughly judge how old it is.

Exposure to a hard blunt object often leads to the formation of wounds - damage to the soft tissue, subcutaneous tissue and deeper tissues and organs. This most often occurs due to impact or compression, but can also occur due to stretching and even friction. Wounds can form within the zone of contact between the surface of an object and the skin and along the perimeter of the zone of contact with it; they may not reflect the shape and dimensions of the contact surface of the object and partially or completely repeat its properties. Wounds can be superficial (within the skin) and deep (penetrating into the thickness of the skin and underlying tissues), slit-like, linear, star-shaped, rectangular and other shapes, and by nature - bruised, lacerated, bruised-lacerated, bitten.

Bone fractures when exposed to hard, blunt objects occur as a result of their deformation - shear, bending, torsion, stretching, compression, or any combination of these factors. In the vast majority of cases, they are observed during injuries. Fractures can be local, structural or mixed, complete and incomplete (cracks), open and closed, single and multiple. They can be located longitudinally, transversely, diagonally, ring-shaped. There are also perforated, depressed, perforated-depressed terrace-shaped, linear, comminuted and impacted fractures. Diagnosis of fractures is carried out by x-ray or sectional examination.

When exposed to hard blunt objects, damage to the brain and internal organs of the thoracic and abdominal cavities often occurs: hemorrhages, tears, ruptures, crushing, and avulsions. They can be of various shapes and sizes, isolated and combined, single and multiple, closed and open, local and distant. The localization and nature of damage to internal organs is determined by the type of traumatic impact, the location and direction of the traumatic force, and the surface area of ​​the traumatic object (Fig. 1-136).

Forearm abrasions. The finely scaly deflated epidermis is displaced in the direction of movement of the traumatic object.

Shoulder abrasions. The wavy arrangement of deflated particles of the epidermis corresponds to the direction of movement of the traumatic object.

Abrasions and bruises on the skin of the forehead from being hit by a bicycle chain.

Round and arc-shaped abrasions in the left temporal region from a blow from the end part of a hollow cylindrical object, a - general view; b - the same close-up.

J

\ Comparison of the shape of the bruises on the back with the shape of the object used to strike (twisted wire).

Rice. eleven.

Longitudinal intermittent abrasions on the skin of the cheek, caused by fingernails.

Rice. 21.

An indeterminate bruise on the back of the thigh caused by a blow from a hard, blunt object with an uneven surface.

Multiple bruises on the skin of the thighs, caused by hissing with fingers to stage an attempted rape.

A bruised wound of a radial shape with pronounced bruising, inflicted with a hard, blunt object with a predominantly flat surface, and - before painting; b - after painting.

Extensive scalp wound in the frontoparietal region. The upper edge of the wound is peeled back and to the left over a significant area, the lower edge is beveled and beveled, and - view on the right; b - left view.

Rice. 41.

Characteristic relative arrangement of abrasions from human bites on the skin of the back.

Multiple slit-shaped lacerations on the face and neck from dog bites and the impact of its claws.

Rice. 46.

Massive hemorrhage into the musculocutaneous flap and under the aponeurosis of the parietal region and an extensive depressed fracture of the bones of the calvarium.

Depressed fracture of the frontal bone caused by impact with a hard object with a limited ribbed surface. In the center of the fracture there is a linear crack, bordered by a circular fracture, from which two meridian lines extend, a - external view; b - view from the side of the internal bone plate.

Rice. 57.

Depressed fracture of the parietal bones in the form of an elongated oval caused by a blow from a hard object with a ribbed surface.

Depressed fracture of the parietal and occipital bones caused by a blow from a hard oval-shaped object with a protrusion on the surface.

Depressed fracture of the parietal bone caused by a hard object with a spherical impact surface.

Depressed fracture of the parietal bone of an oval shape (a) from a blow with the intermediate part of a stick in comparison with the experimental damage depicted on whatman paper (b).

Rice. 64.

Terrace-shaped and depressed fracture of the bones of the calvarium caused by an impact at an angle with an object with a spherical surface.

Multiple fractures of the bones of the calvarium with the formation of radial, circular and meridian lines when exposed to an object with a wide impact surface

Linear fracture of the occipital bone caused by impact with a hard blunt object. The direction of the traumatic force is from left to right and from back to front.

Linear fracture of the occipital bone to the right from the impact of traumatic force in the direction from back to front and from right to left.

Multiple fractures of the bones of the base of the skull in the anterior and middle cranial fossae. The impact of traumatic force is from front to back and from right to left.

Multiple fractures of the bones of the base of the skull in the posterior and middle cranial fossae. The direction of the traumatic force is from back to front and from right to left.

Hemorrhage on the inner surface of the cranial vault according to the location of the bone fracture.

Multiple focal hemorrhages over the dura mater of the cerebral hemispheres due to head trauma with a hard blunt object.

Extensive epidural hemorrhage in the parietal, temporal and occipital lobes of the brain.

Rice. 76.

Compression of the temporal and occipital lobes of the brain during epidural hemorrhage.

Structural compression fractures of the body CVI (a) and Cv (b) in the anterior part from excessive flexion of the neck (longitudinal rasp).

The mechanism and features of local (a), structural (b) and local-structural (c) fractures of ribs during bending deformation due to impact with objects with a limited and wide surface.

Structural incomplete fractures of the ribs with longitudinal splitting along the inner surface in the area of ​​the corner, resulting from bending and torsion deformation.

b

In forensic medical practice, injuries caused by blunt objects are more common than others, since these instruments are widespread and easily accessible.

TO stupid These include objects that do not have sharp edges or sharp ends and, when damaged, have a specific mechanism of action. The diversity of their properties, mechanisms of action, conditions in which they are formed creates difficulty in solving the questions posed when conducting a forensic medical examination. The direction of the external influence, the characteristics of the traumatic surface of the object, the amount of kinetic energy and a number of other factors largely determine the morphological characteristics of the damage. Blunt objects can be hard or soft. Direct disruption of the anatomical structure of the tissue occurs, as a rule, only when exposed to solid objects, so we will only consider them. As already mentioned, the nature of the damage largely depends on the properties of the object, therefore, in a forensic medical examination, it will be important to establish the nature of the instrument of damage.

Classification of blunt objects

By size: 1) With a limited surface - the boundaries of the surface (all or some) do not extend beyond the surface of the damaged part of the body. With a limited surface, the shape and size of the damage are determined primarily by the shape and size of the traumatic surface.

2) With an unlimited surface - the traumatic surface exceeds the impact area. In this case, the shape and size of the damage will mainly be determined by the shape and size of the damaged part of the body.

This classification is relative, since the surface will be limited or unlimited depending on the shape and size of the damaged part, that is, the nature of the tool must be determined in each specific case.

According to the relief: 1) Smooth (flat)

2) Uneven (not smooth, rough)

By shape (only for objects with a limited surface): 1) Flat (triangular, square, rectangular, round, others)

2) Angular (2,3 and polyhedral)

3)Curve (spherical, cylindrical, others)

4) Combined (flat and curved, flat and angular, curved and angular).

By material: 1) Wooden

2)Metal

3) Mineral

In terms of stability: 1) Leaving no traces

2) Leaving a mark-imposition in the area of ​​injury

3) Leaving a mark-layer on a traumatic weapon

Highlight 4 main mechanisms of impact of blunt objects(although in practice their combined action is also found):

1. Impact- a complex short-term process of interaction between a human body or part of the body and a blunt object, in which the object exerts a pulsed unilateral centrifugal effect on the body (The action time can be less than 0.1 - 0.01 s.) In this case, mutual movement or movement of one from objects. The shorter the impact time, the more energy is transferred to the damaged part of the body, the greater the harm that occurs when damaged. And only with an ultra-short impact time does the amount of damage become smaller, since the weapon simply does not have time to influence the body.

Typical damage: abrasions, wounds, dislocations, fractures, concussions of internal organs, body concussion.

2. Compression- the process of interaction of a person’s body or part of the body with two, usually massive, hard, blunt objects, in which both of these objects, acting towards each other, exert a bilateral centripetal effect on the body. Usually only one of the squeezing objects moves, while the other is stationary. The compression time usually exceeds the impact time. The severity of damage depends on the mass, area, and time of contact.

Typical damage: usually found in landslides and road accidents. Signs are imprints of the surface of solid objects, relief, clothing, minor damage to the skin with severe damage to internal organs: ruptures, crushing, moving them into other cavities or out.

3. Stretching- the process of interaction of a body or part of the body with two solid objects that act in divergent directions, exerting a two-way centrifugal effect on the body. Time - 0.1 - 1 s. One object is always motionless, the other moves away from it.

Typical damage: superficial parallel tears of the skin, the formation of tears and patchwork wounds that do not have bruising or bruising at the edges, avulsions of body parts.

4. Friction- the process of surface interaction between the damaged surface of the body and the damaging surface of a blunt solid object, in which both contacting surfaces are displaced in a tangential or tangential direction relative to each other. The severity of the damage depends on the degree of pressure and duration of action.

Typical damage: abrasions with scratches (traces of dragging), abrasion of clothing, skin, bones.

In addition to the traumatic object, the nature of the damage is influenced by: a) the mark-receiving surface - it can be flat, spherical, with underlying soft tissues, close to the bone, etc. b) an obstacle to the contact of the object with the skin - the material and thickness of the obstacle are important; c) static (stamp damage) or dynamic action

subject; skid marks are different; d) force of influence.

Damage from blunt hard objects very diverse. Their action causes all types of mechanical damage. Let's consider the main ones:

1. Abrasion- superficial damage to the skin that does not extend deeper than the papillary layer. The bottom of the abrasion, initially wet and shiny, is located below the level of the surrounding skin. After a few hours it dries out and gradually begins to fill with a crust. Abrasions can be located on any part of the body. The number of abrasions is usually equal to the number of traumatic actions. The size of the abrasion ranges from pinpoint to several 10 (less often 100) cm square. The area of ​​abrasions depends on the area of ​​the surface of a blunt object in contact with the body and on the length of dynamic contact. The shape of abrasions varies and depends on the shape of the traumatic instrument.

2. Bruise- hemorrhage permeating the subcutaneous fatty tissue. At first it has a blue or blue-purple color; from day 3 it acquires a greenish color, and at day 8 it becomes yellowish. Bruising is typical from the action of a blunt hard object and can have a wide variety of localizations. Almost always, one blow with a blunt object will result in one bruise. But with strong blows from elongated objects, two elongated bruises may appear, located on either side of the receding surface of such an object.

3. Wound- damage extending deeper than the papillary layer of skin. . Wounds resulting from the action of blunt objects are divided into

1) Bruised wounds occur from a blow. General signs: uneven, crusted, bruised, often crusted edges. In the depths there are whitish connecting bridges. Formed by objects with an unlimited traumatic surface.

2) Lacerations are formed from stretching. They are characterized by jagged edges.

3) Bruised and torn

4. Fracture - damage to bone or cartilage. Fractures are distinguished: a) from direct contact of a traumatic action - direct - at the point of contact destruction, crushing and mutual layering of bone structures occurs. As a result, small defects are observed at the site of application of force due to chipping of the bone substance. Raised bone plates are visible along the edges of the defect. b) from indirect action - indirect. Their edges represent a finely jagged broken line.

1) Fractures of tubular bones can form from shear, flexion, compression, twisting and avulsion. Shear fractures are always straight, transverse or oblique. A bone fracture occurs at the site where the force is applied. Thin cracks extend from the edges. When bending, tension occurs on a convex surface, and compression occurs on a curved surface. A crack forms on the convex surface, the ends of which are connected on the compression side, forming a large fragment. When the bone is compressed, impacted fractures are formed, characteristic of a fall from a great height. Twisting of a bone is its rotation around the longitudinal axis, causing helical fractures.

2) Fractures of flat bones depend on the shape and size of the traumatic surface and the type of its action - impact or compression. From a blow to the place where the force is applied, unilateral fractures occur.

5. Damage to internal organs can say little about the mechanism of action of a blunt object. When an object with a small mass is applied to the head, injuries occur at the site of application of force - bruised wounds, depressed or comminuted fractures, ruptures of the dura mater. With a head injury, all types of intracranial injuries and hemorrhages can occur; one of the most specific is focal brain contusion. Spinal cord injury occurs only in places where the integrity of the spine is violated in the form of compression fractures and dislocations of the vertebral bodies, ruptures of the ligamentous apparatus and joint capsules. Damage to internal parenchymal organs is varied: hemorrhages, ruptures of the outer membrane, ligamentous apparatus, partial separation, complete destruction or separation of the organ. In case of damage to hollow internal organs, there are: ruptures of the organ wall, intrathecal hemorrhage, damage to the ligamentous apparatus, complete separation of the organ. Severances of organs are observed with strong impacts from massive blunt objects, leading to a general shaking of the body; at the time of injury, a sharp displacement of the organ occurs, leading to rupture of the fixing formations or complete separation.

3.1. The concept of forensic traumatology. Classification of damaging factors. Mechanisms of traumatic action of blunt objects

In forensic medicine, damage or injury is understood as a violation of the anatomical integrity or normal functions of the human body, caused by some environmental factor and resulting in health problems or death. All environmental factors that have a damaging effect on the human body can be divided into physical, chemical, biological and mental. Physical factors include mechanical, temperature, electrical influences, as well as sudden changes in atmospheric pressure and radiant energy. In expert practice, damage caused by mechanical factors is more common. Such injuries occur as a result of the interaction of a damaging object with the human body. The following damaging objects have a mechanical effect: weapons - products specifically designed for attack and defense, tools - products that have a household or industrial purpose, other objects that do not have a direct purpose (stone, stick, bottle, etc.). Depending on the nature of the action, damaging objects (weapons, implements) are divided into blunt, hard (crushing), sharp and firearms.

Injuries from blunt objects are more often the object of forensic medical examination than other mechanical impacts. The number of deaths from them is 45-80% of the total number of deaths due to mechanical damage.

The forensic medical examination carried out in cases of the use of such items should resolve the following main tasks:

1) establishing the nature of the damage;

2) establishing the properties of the damaging object;

3) identification of a number of conditions for the occurrence of damage (mechanism of injury).

There are different classifications of blunt objects depending on the shape of their striking surfaces. The following is most widespread in forensic medical practice (A. I. Mukhanov, 1974):

1) blunt objects with an extensive (predominant) flat traumatic surface.

Their effective surface is larger than the area of ​​contact between the object and the body. Based on damage from such objects, it is impossible to determine the properties and features of the edge of the striking surface, since it is located outside the contact area. An example is a part of a wide board, a wall, the side of a car body, etc.);

2) blunt objects with a limited traumatic surface.

Damage from them fully or partially reflects the shape of the active surface and the properties of its edge. Limited traumatic surfaces can be flat, spherical, cylindrical, and sometimes have a characteristic relief (the surface of a gear, brass knuckles, belt buckles, etc.). Objects with a limited traumatic surface also include those that, depending on their position upon impact, have a trihedral, dihedral angle or edge (for example, a brick, a hammer, an ax head, etc.);

Blunt objects can interact with the human body in different ways, depending on the speed of movement, timing, force and angle of contact. In this regard, several mechanisms (types) of action of blunt objects are distinguished.

Impact is a short-term interaction between an object and a body during movement. The force of the impact depends on the speed and mass of the object. The traumatic effect of an impact is centripetal. Pressure is the prolonged interaction of an object and a body in contact. Depends on the force of interaction and the mass of the object.

Sprain - manifests itself in cases where a traumatic force is directed away from the body, causing tissue ruptures and body parts torn off.

Sliding - occurs when an object moves tangentially in relation to the body.

3.2. Characteristics of certain types of damage

3.2.1. Abrasions

An abrasion is a superficial mechanical damage to the epidermis of the skin or the epithelium of the mucous membranes. In the formation mechanism, the main role is played by sliding, that is, the movement of an object along the surface of the body, and sometimes significant pressure. Sliding and friction lead to the removal of the top layers of skin.

The shape of abrasions is varied. If the sliding surface is wide and uneven, it causes a series of abrasions parallel to each other. Band-like abrasions usually occur due to dragging of the body during transport injuries. When bitten by teeth, focal abrasions occur with a characteristic arrangement in the form of two arcs, the ends facing each other, the action of the nails is accompanied by the formation of semilunar abrasions.

The surface of a fresh abrasion is pinkish-red, moist, soft, painful, located below the level of intact skin. After 6-12 hours, the bottom of the abrasion dries out, redness and swelling appear around it. By the end of the first day, all abrasions have a brownish crust. After 1-2 days, the surface of the abrasion levels out and begins to rise above the border areas of the skin. By 7-10 days, the healing process (epithelialization), going from the periphery of the abrasion to the center, leads to the gradual separation of the crust. The falling off crust reveals a denser, smoother, pinkish-colored area that disappears over time.

Forensic medical significance of abrasions.

Indicator of the action of a blunt hard object;

Indicate the place of application of force;

They may indicate the nature of the violence, the method of causing the damage (for example, semilunar abrasions on the neck when squeezing it with hands; around the mouth and nose - when covering them with a hand; on the thighs of females - during forced sexual intercourse or an attempt at it; in the area hands, wrists, forearms, shoulders - as a sign of struggle, defense, etc.).

Based on abrasions, the direction of the traumatic effect can be determined (by the position of fragments of the epidermis, which are usually directed in the direction of movement of a blunt object; by the folded layer of the upper layers of the skin, found at the end of the abrasion).

Abrasions may reflect the shape of the traumatic surface. This happens when the object or its active part is small in size, has a clearly limited configuration, acts at an angle close to a straight line, and the path it travels along the surface of the body is small.

Analysis of the stages of formation and reverse development of abrasions allows us to determine how long ago they were applied.

3.2.2. Bruising

Hemorrhages as a result of traumatic rupture of blood vessels can form in any internal organs and tissues. Bruises usually include only those hemorrhages in which accumulations of blood form under the skin.

Hemorrhages in soft tissues can also have a non-traumatic origin due to painful changes in blood vessels, leading to an increase in the permeability of their walls (hemorrhagic vasculitis, vitamin deficiencies, exposure to penetrating radiation, certain types of poisoning, acute oxygen starvation, etc.). This circumstance must be taken into account when conducting the examination.

The location, shape, and size of bruises may vary. Small, round, pinpoint bruises are called petechiae; small indeterminate shapes - ecchymoses. There are also hematomas - abundant accumulations of blood with tissue spreading. The shape of bruises is often oval, which corresponds to the configuration of the area of ​​contact of the object with a rounded area of ​​the body.

Oxygen-rich, bright red blood flowing out of damaged vessels, accumulating in the surrounding tissues, saturates them and then undergoes a number of changes, i.e., it has the ability to “bloom.” The “blooming” of bruises is caused by the transformation of the coloring pigment of the blood (hemoglobin) into a series of sequentially formed decay products of different colors.

Initially, the bruise has a purple or purplish-bluish tint (sometimes acquiring a deep blue color), which lasts for 1-4 days. After 4-8 days, the bruise becomes purple with greenish, yellowish tints. Mixed shades last up to 9-12 days, and on days 12-16 the bruise looks yellowish-gray.

The intensity of the “blooming” of a bruise depends on its size, prevalence, location, and constitutional characteristics of the victim. The deeper the bruise is localized, the longer its color does not appear. Superficial bruises become visible within 10-30 minutes after injury; deep bruises may appear several days later.

In loose fatty tissue (perinephric), hemorrhages can spread over considerable distances from the site of application of traumatic force.

Forensic medical significance of bruises:

They are an indicator of the action of a blunt, hard object;

Indicate the place where the traumatic force was applied (where there is a bruise, a blunt object was directly affected). However, in the presence of appropriate anatomical conditions, a bruise is capable of moving along loose fatty tissue to the underlying areas (with a blow to the forehead or bridge of the nose, bruises form around the eyes, a “symptom of glasses” with fractures of the bones of the base of the skull, orbit, and with blows to the lower abdomen - on the thigh);

The bruises can be used to determine (approximately) how long ago they were caused. Since the change in their color depends on many conditions that cannot always be taken into account, determining the duration of the bruise in days should be done with caution;

Based on the shape of the bruises, the outlines of the active part of the object can sometimes be determined (if it had a limited traumatic surface), which in some cases makes it possible to identify the object itself.

Bruises found on the corpse may indicate the nature of the violence.

Wounds are mechanical damage to the integument of the body that penetrates deep into the dermis of the skin or into the subcutaneous (submucosal) tissue.

Depending on the damaging blunt object and the mechanism of injury, wounds are classified as bruised, bruised-lacerated, lacerated, patchy, scalped, and bitten.

The characteristics of wounds are associated with the mechanism of action of the traumatic factor. Contacting the body at the moment of impact, a blunt object compresses and displaces tissues, causing them to stretch, and subsequently crush, leading to rupture of the integument with the formation of a wound.

A specific feature of wounds is the presence of edges, which abrasions and bruises do not have. The edges of the wound are the lateral tissue surfaces newly formed due to trauma. When examining and describing wounds, it is necessary to note the relief of the edges and walls (smooth, uneven, torn), the presence of sedimentation, the connection of two opposite edges with tissue bridges, their integrity or crushing, blood soaked or bloodless, the introduction of foreign particles into the thickness of the edges and other features.

When hit with a blunt object at a right angle, bruised wounds are formed that have uneven jagged edges, rounded, U-shaped ends (on the head the ends of wounds are often sharp, due to the close proximity of the underlying bone), bruising of the edges, bruises in the wound area, uneven walls of the wound canals, from which protrudes hair torn out with hair follicles, connective tissue bridges, crushed edges, sometimes peeled off from the bones.

Ablation of the edges of the wound - occurs at the site of direct action of the object or its edges and is expressed more or less evenly. Where the skin is not so much crushed by the object itself as torn from tension, the edges of the tears may not be besieged.

Since a blunt object, when crushing the skin and underlying layers, kneads the tissue, the edges of the wound in the depths turn out to be uneven. The tissues are not torn deep along their entire length, as a result of which tissue bridges remain connecting the edges of the wound. Hemorrhages into the wound and surrounding tissues occur due to rupture of blood vessels at the point of compression. Where the soft covers are thin and there is bone underneath them, a uniform peeling of the skin from the underlying bone is observed.

When struck with a blunt object at an angle, the wound takes on the character of a bruised laceration. It differs from a bruised wound in the uneven deposition of the edges and detachment of soft tissues. The edges of such a wound are deposited predominantly on the side from which the object is applied, and the detachment of the skin from the underlying layers is more pronounced on the opposite side. Skin detachment in the area of ​​a bruised wound is presented in the form of a “pocket” directed towards the action of the traumatic force.

When struck at an angle to the surface of the body, followed by displacement and tearing of the skin in the form of a flap, a patch wound is formed. Its variety - a scalped wound - occurs when the skin is torn away from the underlying layers over a significant extent.

Bite and laceration wounds arise from the action of teeth, and particular importance is attached to wounds from bites by human teeth. Bite wounds are located in the form of one, or, more often, two arcs and consist of individual damage, to one degree or another reflecting the shape of the active surface of the teeth. The general curvature of the arches, the size and shape of individual damage elements, the distance between them, traces of defects or the absence of a particular tooth and other features, being in some cases quite well expressed, can be used for identification. Such damage must be photographed as quickly as possible using a scale ruler at the crime scene.

Forensic medical significance of wounds:

Bruised, bruised-lacerated wounds and their varieties, which have a combination of certain signs (unevenness, bruising, bruising of the edges, tissue bridges, etc.), are an indicator of the action of a blunt object;

Indicate the place of application of the action of a blunt object;

When a blunt object is applied at an angle, the properties of the wounds make it possible to determine the direction of the traumatic force (maximum aggravation of the edges - on the side of the impact, predominant detachment of the skin from the underlying bone - in the direction of the acting force);

The degree of healing of wounds and the condition of the scars that appear in their place makes it possible to speak about the duration of the damage;

Features of wounds (shape, size, nature of injury, etc.) sometimes allow one to judge the configuration and size of a blunt object or part of it, speak out about its classification into a certain group, and the possibility of causing a wound by the object presented for examination. However, it should be borne in mind that the expert’s conclusion in such cases is presumptive.

3.2.4. Bone damage

The characteristics of fractures largely depend on the type of bones, the nature of the damaging object, the strength and speed of the traumatic effect, as well as on the direction of the force in relation to the damaging surface. In this case, fractures can occur both at the site of application of the acting force (direct, contact) and at a distance from it (indirect, remote). The mechanisms of fracture formation are stretching, bone compression, or a combination of both.

There are complete (separation of the bone through the entire thickness) and incomplete (partial damage to the bone), open and closed fractures. Incomplete fractures include cracks and fractures. Damage to bones has certain properties that indicate the impact of blunt objects acting with great force. The features of some fractures (perforated, depressed) allow us to judge the shape and size of the surface of the damaging object. Damage to bones makes it possible to differentiate direct and distant fractures and thereby judge the nature of the deformation, the place of application of force and the direction of the traumatic effect.

The relative position of local fractures and cracks extending from them that occur during repeated impacts of an object sometimes makes it possible to establish the number of blows and the sequence of their infliction. Based on the characteristics of bone fractures, a specific mechanism of injury can be established (impact, one- or two-sided impact, torsion, rupture, and other options).

Damage to the bones of the skull is observed relatively often in forensic practice. Their occurrence is associated with a change in the configuration of the skull under the influence of an impact. Damage to the bones of the skull (fractures and cracks) can be closed (without breaking the integrity) or open, accompanied by a violation of the integrity of the soft tissues and exposure of the damaged area of ​​the bone. Open fractures can be non-penetrating or penetrating into the cranial cavity.

Among closed skull fractures, the most common are fractures of the vault, in second place are fractures of the vault and base, and in third place are fractures of the base of the skull.

On the round vault of the skull, at the site of action of a blunt object with a limited traumatic surface, the compressed area of ​​the bone bends. If the elasticity of the bone is sufficient and the flattening is small, then after the cessation of action the bone returns to its original position. Bone tissue is more resistant to compression than tension. Therefore, it may happen that at the site of impact, the outer plate of the bone, which has been subjected to predominant compression, and is also thicker, remains intact. In the inner part, which experiences tension during deflection, a fracture will occur in the form of a crack. With a greater impact force, the outer bone plate is also damaged, not only at the site of the impact, but also at some distance. When the object acts perpendicularly, the cracks spread more or less evenly along the radii. If a blunt object acts at an angle, the cracks are located more in the direction of impact.

Typical violations of the integrity of the skull bones are caused by blunt objects with a limited surface area, if it does not exceed 16 cm2. With a significant impact force, perforated fractures occur when a section of the bone seems to be knocked out by the edges of the damaging weapon. The edges of such a fracture are beveled from the inside, and its external outlines often reflect the size and configuration of the damaging weapon. If an object with edges acts not perpendicularly, but at an acute angle, then only part of its surface comes into contact with the tissues, for example, some corner of a hammer. This part of the object, penetrating relatively deeply, presses the bones here, and the opposite part may not even touch the bones. With such uneven deepening of a blunt-edged object, terrace-like fractures are obtained. With them, the depression in the bones forms a slope, sometimes consisting of 2-3 steps rising one above the other, forming a staircase in section. Stepped impressions indicate the action of a blunt-edged object at an angle.

With a lower force and speed of impact and a larger area of ​​the striking surface, depressed fractures are formed, which can repeat the outlines of the traumatic object or part of it, as well as comminuted fractures with fragments that are not immersed or partially immersed in the cranial cavity. The outline of the object is most pronounced at the site of action of the edges of the damaging object.

Fractures that occur at the site of direct trauma to the bone are often accompanied by the formation of cracks extending laterally from the point of application of force (radial cracks). If the blow is applied perpendicularly, the cracks spread evenly along radii. If a blunt object acts at an angle in a certain direction, then this direction dominates among the radiating cracks. Therefore, the direction of the cracks from the point of indentation indicates the direction of the force acting upon injury. With strong impacts, leading to flattening of a part of the skull, the injured segments bend, and, as a consequence, circular (concentric) cracks appear. Frequently occurring cracks at the base of the skull are also an indicator of the direction of the impact force. Since blows to the head are applied from top to bottom, cracks most often go to the base and base of the skull. They are rare in the direction towards the top of the skull, for example, from the forehead or back of the head to the crown.

If the blows are applied repeatedly, then in this case it is very important for the expert to decide the question of the sequence of damage. In some cases, this can be established using the sign of mutual limitation of cracks (Chavigny-Nikiforov sign). The subsequent crack does not cross the cracks from the previous blow.

When exposed to blunt objects with a large traumatic surface, the patterns of damage to the skull bones are the same as when exposed to blunt objects with a limited surface, but these damages are more extensive.

One of the common types of injuries, along with skull fractures, is a violation of the integrity of the chest bones. The rib cage is a complex complex that includes the ribs, collarbones, shoulder blades, sternum, and thoracic spine. The ribs are most often injured. They are flat bones with outer and inner compact plates with spongy substance enclosed between them. In front, the bony part of the rib (except XI and XII) passes into the cartilaginous part, which is attached to the sternum; in the back, the ribs are attached to the bodies and processes of the vertebrae.

When struck by an object with a limited traumatic surface, the rib at the point of application bends inward, while the outer plate is subjected to compression, and the inner plate to tension. This leads to a rib fracture (partial or complete) at the site of application of force, with predominant damage to the internal bone plate. The outer plate may remain intact or become damaged, and then a complete rib fracture occurs.

With a complete fracture, additional cracks can be found on the internal plate; the ends of the rib fragments face inside the chest cavity, often damaging the pleura. Severe hemorrhages occur in the soft tissues in the area of ​​the fracture. At the moment of impact, the costal arch bends and a stretch occurs on its outer surface, at a considerable distance from the point of impact of the object, resulting in the formation of a distant fracture with a predominant lesion of the outer bone plate. If such a fracture is complete, the broken ends of the ribs are turned outward, the parietal pleura is not damaged, and hemorrhages in the surrounding tissues are insignificant.

When the pelvic bones are damaged by a blow from a blunt object from the front, the destruction is localized in the anterior semi-ring, mainly in the area of ​​the horizontal branches of the pubic bones with the formation of small fragments. When struck from the side, fractures of the pelvic bones are localized at the point of application of force. In a rear impact, the greatest destruction of bones also occurs at the site of application of force - a transverse fracture of the sacrum occurs, as well as damage to the wings of the iliac bones and ruptures of the sacroiliac joints.

3.2.5. Damage to internal organs

Among injuries to internal organs, a special place is occupied by brain injury, which can accompany skull fractures, or be observed while maintaining the integrity of the cranial bones. Traumatic brain injury is often the cause of death of the victim.

Traumatic brain injury can be open or closed. The most difficult to diagnose is a closed craniocerebral injury, which occurs from a blow to the head with a blunt object or as a result of a fall. The following main types of closed craniocerebral injury are distinguished: concussion; brain contusion; compression of the brain by blood escaping from damaged vessels (hematoma).

A concussion is characterized by molecular changes and is not accompanied by macroscopically pronounced changes. The decisive factor in a concussion is not anatomical, but functional disorders (in some cases, these disorders can lead to severe disorders, even death).

A brain contusion is usually combined with a concussion and is accompanied by local anatomical disorders in the brain matter, in the form of one or more foci of destruction (crushing, hemorrhage). Destruction of brain matter can occur either directly at the site of impact or on the opposite side. The occurrence of direct or anti-impact (counter-impact) injuries is largely due to the mechanism of traumatic impact.

When a head is struck at rest, the configuration of the bone changes: it bends inward, and then straightens due to elasticity. When the bone bends inward at the site of impact, positive pressure first arises, which changes to negative. In this case, gas bubbles are released from the tissues and blood, followed by their collapse, causing destruction of the brain matter (this phenomenon in physics is called cavitation). This is how a bruise occurs at the point of impact. Impact injuries to the brain from a blow to the head with a blunt object are, as a rule, absent or appear with a very high impact force and are insignificant.

A blow to the head moving at a certain speed, which happens when the victim falls or suddenly brakes when colliding with an obstacle. Under these conditions, a traumatic brain injury of “acceleration” occurs of the “impact - counter-impact” type. According to the place where the force is applied, positive pressure arises in the cranial cavity, decreasing in the direction of the impact and turning into negative pressure due to the “lag” of the brain on the side opposite to the impact. It is in this place that, as a result of negative pressure and the resulting cavitation, extensive foci of brain contusion from counter-impact, typical of acceleration trauma, are formed. There may not be any brain damage at the site of the impact, and if it occurs, it is always less pronounced than in the area of ​​the counter-impact.

Compression of the brain occurs due to the development of a traumatic hematoma - an accumulation of blood in the cranial cavity. Hematomas are formed when the vessels of the membranes or the brain itself are damaged. When struck with a blunt object in the temporal or parietal region, an epidural hematoma occurs (an accumulation of blood between the dura mater and the bones of the cranial vault. The dura mater is damaged by the sharp edge of a crack in the internal bone plate, as a result of which blood pours out between the wall of the skull and the brain and, accumulating, compresses the brain In this case, painful disorders do not occur immediately, but after some time necessary for the formation of a hematoma in a critical volume (at least 60-70 cm3). The duration of the “clear interval” depends on the caliber of the damaged vessel, the rate of blood flow and a number of other circumstances ( hours-weeks). This is of particular importance when assessing a specific version, when bodily injuries resulting in the death of the victim were inflicted at different times and, especially, by different persons.

Other internal organs can be injured to a large extent due to impact and shaking, while the skin is often undamaged. The propagation of a shock wave through a parenchymal organ (spleen, liver, kidneys) causes rupture and cracking of the capsule and tissues of the organ. Zigzag, slit-shaped damage occurs, located parallel to each other. There may also be ruptures of the heart and lungs. The latter often rupture from direct damage to their ribs. The impact can also manifest itself in the form of hemorrhages or ruptures in the area of ​​the suspensory ligaments, due to their overstretching, which is especially typical when falling from a height.

When analyzing each specific case, a forensic expert evaluates damage to soft tissues, bones and internal organs in their entirety, comparing them with each other and with damage to the victim’s clothing. Only with this approach can one of the main and most important issues be correctly resolved - the question of the mechanism of injury.

The degree of reliability of the expert’s conclusion increases even more if, in addition to assessing morphological data, the results of additional laboratory studies are used, which is especially important when deciding on the possibility of causing damage by an object or instrument presented for examination as material evidence. Among the main issues that must be resolved during a forensic medical examination of injuries caused by blunt objects, the following can be identified:

What is the nature of the victim’s physical injuries (abrasions, bruises, wounds, dislocation, fracture, organ rupture, etc.)?

What object caused the damage? In particular, could these damages have been caused by an object or instrument presented for examination as material evidence?

Was damage caused by one or more items?

How many blows were inflicted on the victim, in what direction or from which side were they struck?

If there was compression of the body or part of it, then from what side and in what direction did the compressive object act?

In what position (standing, sitting, lying) or what position was the victim in and what was the relative position of the victim and the striker at the time of the injury?

How old are the injuries on the victim’s body?

During the forensic medical examination of corpses, in addition to the main questions, a number of others are posed, which are common to all cases of traumatic death. These are questions about the cause and duration of death; about signs indicating struggle and defense; about the possibility of the victim taking any independent actions after receiving an injury; about whether the victim took food, when, what and in what quantity; whether he drank alcohol shortly before his death and what was the degree of intoxication. A special place (especially during the examination of living persons) is occupied by the question of the severity of the injuries received.

Injury with blunt objects constitutes the most numerous group of mechanical injuries. A wide variety of objects found in everyday life and at work (hammer, iron, stick, stone, etc.), as well as specially made for attack weapons - brass knuckles, handheld, flail. Injuries caused by hands, feet, teeth, etc. are most often also in the nature of blunt trauma.

Most damage caused by parts of moving vehicles, damage caused by a fall from a height or as a result of compression of the body, for example during landslides, leave marks on the human body that are characteristic of the action of a blunt hard object.

What is characteristic of a blunt weapon is, first of all, the presence of a blunt striking surface (if there are edges and faces, it is blunt-edged), and its effect on the body is expressed in compression and displacement of tissues.

Depending on the force with which a blunt object acts, injuries of an extremely varied nature are formed on the body, ranging from the lightest to the most severe (abrasions, bruises, wounds, bone fractures, dislocations of joints, ruptures and crushing, crushing and dismemberment). However, despite the variety of blunt objects and the injuries they cause, the mechanism of formation of these injuries can be reduced mainly to three types: impact and shock, compression and friction.

On impact At the point of contact of the body with a blunt hard object, various injuries occur, the nature of which is determined by the force of the blow, the size and shape of the striking surface of the weapon, the anatomical features of the body structure in the area of ​​damage, the condition of clothing and many other factors.

A small impact is accompanied by the formation of abrasions and bruises without violating the integrity of the skin of the body. Strong impacts with blunt hard objects directly at the point of application of force cause wounds, bone fractures, ruptures of internal organs and other damage. In addition, they are usually accompanied body concussion with the formation of multiple hemorrhages in different parts of it, including at a distance from the site of impact.

The main mechanism for the formation of damage when moving vehicles, in cases of collapse and crushing of the body by heavy objects is body compression which is characterized primarily by crushing of soft tissues and internal organs, multiple splintered bone fractures, and often, when moving on the wheels of rail vehicles, separation of the body into parts.

When a blunt object comes into tangential contact with the body, as well as in cases where the body is dragged along the ground during a transport injury, the main mechanism for the formation of damage is friction. In this case, relatively superficial damage in the form of abrasions and shallow wounds most often occurs. However, sometimes, as a result of dragging and friction, deep damage can occur, involving not only soft tissue, but also bones.

Forensic medical practice shows that the individual types of damage mechanisms described above under the action of a blunt hard object are often combined with each other, which leads to the formation combined injuries and sometimes creates great difficulties during the examination.

One of the characteristic features of trauma with blunt objects is the often detected discrepancy between relatively minor injuries on the surface of the body in the form of abrasions and bruises and extensive ruptures and crushing of internal organs, multiple bone fractures, etc., established during an autopsy.

Characteristics of certain types of injuries from blunt objects.Abrasion represents a superficial violation of the integrity of the skin or mucous membranes; with deeper damage to the skin and mucous membranes, superficial wounds occur. Abrasions are formed as a result of impact, friction or compression of the body with blunt and hard objects that have an uneven (rough) surface. The integrity of the skin and mucous membranes can also be damaged when the pointed end of objects such as a needle, knife, nail, etc. slides over the surface of the body; The resulting linear abrasions are usually called scratches.

The forensic medical significance of abrasions and scratches is very great. First of all, it is an objective indicator of the fact of injury and the place of application of force. The shape, size, direction and location of abrasions help to clarify the mechanism of injury - one of the main issues of interest to the investigation.

The shape of abrasions is very diverse and depends largely on the nature of the striking surface of the object. Sometimes the shape of the abrasion reflects the shape of the damaging object, but this is rare in practice. The exception is the very characteristic abrasions caused by nails and teeth.

In some cases, with a detailed examination of the abrasion (according to the degree of its severity along the length and at the ends, the surface topography, the direction of the scales of the exfoliated surface layer of skin, etc.), it seems possible to establish the direction of movement of the damaging object. The solution to this issue is made easier in the presence of multiple parallel linear abrasions, often formed when the body is dragged. Establishing the direction of movement of the damaging object is important for reconstructing the picture of the incident, for example, in car accidents.

Sometimes the location and shape of abrasions are so typical that they even indicate a certain type of violence. Thus, semilunar abrasions from nails on the neck, around the mouth and nose are characteristic of strangulation; the presence of such abrasions and bruises on the inner thighs and near the genitals in women indicates possible rape or an attempt at it.

Precipitation can also form after death as a result of the action of blunt hard objects. It usually looks like uniform, dense yellow-brown spots, somewhat sunken in relation to the level of the surrounding skin. These stains look and feel like parchment and are therefore called “parchment stains.”

Evidence of the intravital origin of the abrasion is the detection of a bruise in the subcutaneous tissue, as well as signs of its healing, in particular the presence of a crust rising above the level of the skin. However, these signs are expressed only in cases where several hours have passed from the moment of injury to death. It is difficult, and sometimes impossible, to distinguish between abrasions caused immediately before death or shortly after it.

Consecutive changes occurring in the intravital abrasion during its healing process make it possible to judge how long ago the damage was caused. A fresh abrasion has a wet surface, then it dries and a crust forms (after 12 - 24 hours). Under the resulting crust, the abrasion is healing. Gradually, starting from the edges, the crust peels off and disappears 7 to 12 days after the injury. After healing, a smooth pinkish spot forms at the site of the abrasion, which becomes invisible after 10 - 15 days.

Bruise, It is an accumulation of a certain amount of blood under the skin, released as a result of rupture of small blood vessels. Translucent through the skin, it changes its color, gives the skin a blue-purple color and therefore is called a bruise in everyday life.

The severity of the bruise depends primarily on the amount of blood shed, the depth of its location and the location of the damage. In places where there is a lot of loose fatty tissue, for example in the area of ​​the eyelids, mammary glands, genitals, bruises occur with relatively light blows, often reaching significant sizes and are accompanied by severe swelling.

Sometimes, with severe trauma, crushing and separation of soft tissues are observed with the formation of cavities filled with blood. Such large accumulations of blood in cavities or interstitial layers are called hematoma,

The forensic medical significance of bruises and hematomas is mainly as follows: same, as well as abrasions. First of all, they are objective indicators of mechanical impact and indicate the place of application of force.

The shape of the bruise is irregularly round or oval. Only in some cases can it indicate the object that caused the damage. Thus, very characteristic bruises are formed when struck by a belt buckle, chain, stick, rope loop, etc. (Fig. 2).

Small round or oval bruises are formed when soft tissues are compressed by the fingers. The localization of such bruises in certain places, for example on the sides of the neck, on the inner surfaces of the thighs or in the genital area of ​​a woman, sometimes allows us to judge the nature of the violence that took place.

A certain importance is attached to bruises when deciding how long ago the damage was caused. In the first days after the injury, the bruise usually has a blue-reddish or purplish-blue color, which gradually changes: along the periphery the bruise begins to acquire a greenish color, 6 - 9 days after the injury it becomes yellow, and after 12 - 14 days it disappears completely. These changes in color are associated with the transformation of the coloring substance in the blood - hemoglobin - in the bruise.

Rice. 2. Bruising from being hit by a belt loop

The vast majority of injuries caused by blunt objects result in bruising. Therefore, they serve as an important indicator of the lifetime of damage. However, it should be borne in mind that injuries caused shortly after death (10 - 30 minutes) may also be accompanied by the formation of bruises that are externally similar to those seen during life. Therefore, in some cases it is very difficult to resolve the issue of intravital or postmortem origin of damage.

And finally, it should be borne in mind that sometimes cadaveric spots (see Chapter 25), which are sometimes very similar in appearance, can be mistaken for bruises.

Wound is a damage accompanied by a violation of the integrity of the entire thickness of the skin or mucous membrane, and often the underlying soft tissues. If a wound penetrates any body cavity (cranial, thoracic or abdominal), it is called a penetrating wound.

Depending on the mechanism of formation, wounds caused by blunt hard objects can be divided into two main types: bruised and lacerated. Bruised wounds are formed as a result of squeezing, stretching the skin and breaking its integrity. Most often they occur in those parts of the body where bones are located close to the skin, for example on the head, the front of the lower leg, the knee joint, etc.

The size and shape of bruised wounds are very diverse and depend primarily on the size and shape of the striking surface of the object and the structural features of the body in the area of ​​damage. When struck by blunt objects with a more or less wide flat surface, bruised wounds of an arcuate, star-shaped, zigzag or indeterminate shape are formed. When struck by blunt hard objects with a cylindrical striking surface (log, pipe, etc.), bruised wounds of irregular shape are observed with skin abrasion at the edges and crushing of soft tissue in the center.

Sometimes blunt-edged objects, such as a hammer, an ax head, or an iron, cause bruised wounds that reflect some of the characteristics of the striking part of the object. Thus, a blow with a square hammer often results in a U-shaped wound, a blow with a round hammer often results in an arcuate wound, etc.

Rice. 3. Bruised wounds

Wounds from blunt objects have characteristic edges, angles and wound surface (bottom). Their edges are uneven, crusted, soaked in blood, crushed and often detached from the underlying tissues (Fig. 3); the bottom is uneven, bruising; in the depths of the wound, especially in its corners, between the edges of the damage, thin thread-like bridges of unruptured tissue are found. Wounds caused by blunt objects usually bleed little.

The described signs make it possible to recognize bruised wounds upon careful examination without much difficulty. The exception is bruised wounds of a linear shape with relatively smooth edges and pointed corners. In appearance they are very similar to cut or chopped wounds. To avoid mistakes, it is necessary to carefully examine the bottom and edges to detect connective tissue bridges, which always occur in bruised wounds and are not observed in cut and stab wounds.

Bruised wounds have important forensic and forensic significance. They make it possible to establish the fact of the use of a blunt instrument, often make it possible to judge the characteristics of the damaging object (the presence of edges, corners, etc.), and their location, quantity and severity often make it possible to determine the nature of the violence.

Sometimes, in the depths and along the edges of the wound, particles of the object that caused the injury (chips, glass fragments, bricks) can be found, which can help in identifying the crime weapon.

If a hard, blunt object acts at an acute angle to the surface of the body, lacerations are formed as a result of stretching and tearing the skin. They have many common symptoms with bruises, but crushing and bruising of the edges, as well as bruising of the surrounding skin, are weak or absent altogether. In forensic medical practice, bruised and lacerated wounds are often encountered, in which signs of both wounds are observed.

A type of laceration and contusion wounds are bite wounds caused by the teeth of animals and humans. Bite marks from human teeth can sometimes serve as the subject of forensic medical examination in order to identify the person who caused the damage.

Lacerated wounds are also formed as a result of rupture of soft tissues and skin in the direction from the inside to the outside by fragments of broken bones. Unlike bruised wounds, such wounds do not have skin aggravation and crushing of the edges.

In forensic medical practice, it is often necessary to resolve the issue of how long ago a wound was caused. This is done based on studying the signs of healing. It should be borne in mind that the healing time of bruised and lacerated wounds largely depends on the size, location, infection, method of treatment and other factors. Therefore, the assessment of the age of wounds caused by blunt objects must be approached with caution. If the wound has healed and a scar has formed in its place, it is extremely difficult to determine how long ago the injury occurred.

Bone fracture often occurs as a result of exposure to blunt hard objects. In the long tubular bones of the upper and lower extremities, transverse, oblique, comminuted and spiral fractures are observed.

Bone fractures accompanied by a violation of the integrity of the skin are called open, and without a violation - closed. According to the mechanism of origin, a distinction is made between direct fractures, which form at the point of application of force, and indirect, or indirect, fractures, which occur at a distance from the point of impact.

By the nature of the fractures one can sometimes judge the mechanism of injury, the direction of the blow and the position of the victim at the time of injury.

In forensic medicine, damage to the bones of the skull is of greatest importance: cracks, suture discrepancies and fractures - depressed, perforated and splintered. Cracks in the bones of the skull can be through (penetrating through the entire thickness of the bone) or non-through. They are formed as a result of deflection of the skull bones in the area of ​​​​a strong impact. Cracks often branch at an acute angle, with its apex, as a rule, facing the place where the force is applied. The greatest gaping of cracks is observed near the impact site, and their direction usually coincides with the direction of the damaging force. The divergence of the sutures between the bones of the skull according to the mechanism of formation is similar to the origin of cracks and is often combined with them.

As a result of blows to the head with blunt hard objects with a small surface, for example a hammer, so-called perforated fractures are formed on the bones of the skull, reflecting to one degree or another the shape and size of the striking surface, and in shape and size they sometimes exactly correspond to the striking surface of the weapon that caused injury, which is important for identification.

When struck by blunt hard objects with a limited cylindrical or blunt-edged surface (crowbar, brick, etc.). Depressed fractures form on the bones of the skull, consisting of several interconnected fragments that protrude into the cranial cavity and injure the brain (Fig. 4).

As a result of an impact with massive heavy objects, for example, during a transport injury or a fall from a height, splintered fractures of the bones of the vault and base of the skull are formed. The direction of the main lines of fractures, as a rule, coincides with the direction of external influence. Comminuted fractures can also occur as a result of multiple blows to the head with a relatively small blunt object; this is characterized by the presence of multiple bruised wounds on the soft tissues of the head.

Rice. 4. Depressed skull fracture from a stone blow

A strong blow with an object with a wide striking surface causes the formation of a comminuted fracture as a result of cracking of the skull (Fig. 5). An extreme degree of compression of the skull, for example, by a car wheel, is characterized by flattening of the head and crushing of the brain. Such trauma in most cases ends in death at the scene of the incident.

As a result of the action of blunt force on the human body, sprains and dislocations of joints. In forensic medical practice, these injuries are less common than bone fractures and are usually combined with them. From dislocations one can sometimes judge the mechanism of injury and the force of external influence.

Damage to internal organs from the action of blunt objects they occur in the form of hemorrhages, avulsions, ruptures and crushing. The nature of these injuries also has a certain significance for establishing the mechanism of injury.

Hemorrhages occur from both blows and concussions and are usually combined with ruptures and crushing. With strong impacts and concussions, for example, during transport trauma, falls from a height, collapses and compression of the body by heavy objects, separations and ruptures of internal organs are observed. However, it should be borne in mind that ruptures can also occur from blows from relatively small objects, such as a stick, a stone, or a fist or a shod foot.

Rice. 5. Comminuted fracture

The nature of the damage depends not only on the force of the blow, compression or shock, but also on the anatomical structure of the organ itself. Most often the liver and spleen are ruptured, less often the lungs, stomach, intestines, and bladder.

Compression of the body with very great force, for example, when driving over the wheels of a vehicle or being squeezed between cars, or when heavy objects fall on the body, is accompanied by crushing and mashing of individual organs and even the entire body.

With crush injuries, complete destruction of the organ is observed, and as a result, along with crushing of tissues and organs, fractures and crushed bones also occur.

Complete or incomplete separation of the body into separate parts occurs when a blunt solid object with a limited surface is acted with great force, for example, when moving with a wheel of a rail vehicle.

A blow to the head from a blunt object or hitting your head on a blunt object from a fall can cause a concussion. At the same time, sometimes there are no noticeable signs of damage in the area of ​​impact.

A concussion is accompanied by loss of consciousness lasting from several minutes to several hours - and even days (depending on the severity of the injury). In severe forms of concussion, death can occur quite quickly due to dysfunction of the central nervous system. At the same time, at the autopsy of the corpse, no noticeable anatomical damage was found in the brain.

Blows to the head are often accompanied by ruptures of blood vessels with hemorrhages under the membranes of the brain. Blood flowing from a ruptured vessel accumulates in the cranial cavity, causing compression of the brain and disruption of its functions, which can lead to death. Blows to the head with a blunt hard object sometimes cause brain contusion with hemorrhage into the substance; It should be borne in mind that a brain contusion is often located not at the site of a blow to the head, but on the opposite side, in the area of ​​the so-called counter-impact.

If there are multiple injuries with blunt objects on a corpse, it is difficult to decide whether they were caused by one or several objects, since, on the one hand, different blunt objects often cause similar injuries, and on the other hand, traces of the action of the same object can have a different appearance. Only the sharp difference in the nature of the damage itself allows us to judge that it was caused not by one, but by several blunt objects.

The main tasks of forensic medical examination in cases of injuries with blunt objects are to establish signs by which one can judge the nature of the damaging object, its shape, size and individual qualities, the direction of the blow, the sequence of damage (if there are several injuries on the body), the damage caused one or more tools, the position of the victim during the injury, the relative position of the victim and the attacker, etc. In addition, in all cases, the issue of the severity of bodily injuries in a living person and the cause of death in the deceased is decided.

Damage from impacts from falling from a height are accompanied by the formation of characteristic damage that makes it possible to exclude other types of mechanical injury. Typically, internal damage predominates over external damage. On the skin, in places where the body comes into contact with the striking surface, only small abrasions, bruises, and sometimes lacerated wounds are formed. During internal examination, as a rule, deep massive hemorrhages, ruptures, and sometimes separations of internal organs, and splintered fractures of many bones (ribs, skull, limbs, etc.) are discovered.

A fall on one's feet causes symmetrical fractures of the heel bones, so-called impacted fractures of the legs, hips, and fractures of the base of the skull, in which the cervical spine is wedged into the cranial cavity and the head appears to be impaled on the spinal column. A fall on the buttocks is accompanied by spinal fractures, and a fall on the head is accompanied by comminuted skull fractures, brain damage and fractures of the cervical spine.

A fall from a height is usually an accident, less often a suicide; killing by dropping from a height is rare. There are essentially no forensic medical signs that allow us to judge the type of death in a fall from a height, and an expert, based on an examination of the corpse, often cannot determine the type of violent death. However, he can detect other types of injuries on the corpse (knife wounds, gunshot wounds, marks on the neck from finger pressure, etc.), suggesting that the corpse of a previously killed person was dropped from a height. In this case, both intravital damage that led to death and post-mortem damage resulting from dropping the corpse from a height are found on the corpse.

When falling from a small height, for example from the height of one's own height, fractures of the upper and lower extremities, ribs, concussions and bruises of the brain, cracks and fractures of the skull are also sometimes observed. The latter are most often located in the occipital or temporal regions, where in the soft tissues corresponding to the place of impact, as a rule, there are bruises, abrasions and bruised wounds.

Causes of sports injury most often are improper organization of sports activities, ignoring protective equipment and measures to prevent injury, non-compliance with the rules of “insurance” of the athlete, premature admission to classes after an illness, and sometimes the conscious use of prohibited techniques by athletes.

Sports injury usually becomes the object of forensic medical examination in cases of fatal injuries. Among them, the most common are fractures of the cervical spine with damage to the spinal cord (when jumping head-first into water, when falling from gymnastic apparatus), less often - severe head trauma with fractures of the skull bones and hemorrhages under the meninges (during wrestling, boxing, falls) and even more rarely - damage to the chest and abdomen.

When investigating sports injuries, in addition to a forensic physician, physical education doctors, qualified athletes, instructors and coaches should be involved as experts and the circumstances of the injury should be carefully studied. Strict adherence to sports rules and medical control requirements is the best way to prevent sports injuries.

Forensic medical characteristics and assessment of injuries with blunt hard objects: lecture // Selected lectures on forensic medicine (forensic traumatology) / Lev Moiseevich Bedrin. - Yaroslavl: Yaroslavsk. state honey. Institute, 1989. - P.19-40.

Forensic medical characteristics and assessment of injuries with blunt hard objects: lecture / Bedrin L.M. — 1989.

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Forensic medical characteristics and assessment of injuries with blunt hard objects: lecture / Bedrin L.M. — 1989.

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Forensic medical characteristics and assessment of injuries with blunt hard objects: lecture / Bedrin L.M. — 1989.

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/ Bedrin L.M. — 1989.

The majority of mechanical damage (up to approximately 80%) is caused by blunt objects, which are most common in everyday life and technology. The word “blunt” characterizes, first of all, the surface of the object, which is in contact with the body at the moment of damage. Blunt objects can be hard, elastic or soft (pillow, rope, etc.). Mechanical damage is usually caused by blunt, hard objects.

Blunt objects themselves vary in their mass, density, and characteristics of the traumatic surface. The conditions under which these objects cause damage also differ: kinetic energy at the moment of contact (impact) of a blunt object with the human body; place of contact (localization of damage); the angle at which a blunt solid object acts. The characteristics of the damaged part of the body are also different. All this causes a wide variety of morphology and functional manifestations of damage from blunt hard objects.

At the same time, all injuries from blunt hard objects have similar, typical group signs and features that allow them to be differentiated from other mechanical damage.

The characteristics of their surface are important in the nature of damage from blunt hard objects.

An idea of ​​the nature of the damaging surface of blunt hard objects is given by the classification developed by A.I. Mukhanov (Table 6).

Table 6

CLASSIFICATION OF DULL HARD OBJECTS ACCORDING TO A.I. MUKHANOV (1969)

1. Blunt hard objects with a flat predominant surface (board, slab, etc.).
2. Blunt hard objects with a flat limited surface: rectangular, triangular, round (hammer, stone, etc.).
3. Blunt hard objects with a spherical surface (dumbbells, weights, etc.).
4. Blunt hard objects with a cylindrical surface (stick, pipe, etc.).
5. Blunt hard objects with a surface ending in a triangular corner.
6. Blunt hard objects ending in a dihedral angle or edge.

The above classification does not take into account the relief of the damaging (mark-forming) surface of a blunt hard object. This is taken into account in the classification of A. A. Solokhin and A. I. Kuzmin, who propose to distinguish between smooth or embossed surfaces with different patterns.

Thus, the classifications provide characteristics of the DIMENSIONS of the traumatic surface, its SHAPE and RELIEF.

Mechanisms of damage caused by blunt hard objects

At the moment of contact of the traumatic surface of a blunt solid object, if it has sufficient mass and kinetic energy, with the human body, damage is formed. Several basic mechanisms are involved in its formation: IMPACT, COMPRESSION, STRETCHING, FRICTION.

IMPACT is a sudden mechanical action when a blunt object moving at a certain speed comes into contact with one or another part of the body* or a person's body moving at a certain speed comes into contact with the surface of a blunt solid object.

The moment of contact (contact) of a blunt solid object and a part of the body is currently called IMPACT.

As a result of the impact, injuries such as bruises, abrasions, bruises, bruised wounds, depressed fractures, and concussion of the body or its parts occur.

It is worth dwelling on a concussion, which is a complex of functional and morphological changes that occur in tissues and organs when a body or part of it is suddenly shaken as a result of a strong blow. The extent of these changes may vary and depend on the force of the impact and the area of ​​the body affected by the shock. With not very strong impacts, predominantly functional disorders occur, for example, a concussion; with stronger impacts, concussions occur, characterized by both functional and pronounced morphological manifestations (for example, ruptures or even separations of internal organs, hemorrhages into their parenchyma and ligamentous apparatus, etc. may occur). When a blow causes a concussion, they speak of concussion syndrome.

COMPRESSION - (compression) the action of two or more blunt objects of significant mass directed at the body or part of it in converging directions. In practice, it often happens that one of the compressive objects is in motion, while the other is motionless. Compression is characterized by extensive damage to internal organs and bones with intact or minor damage to the soft tissues of the body.

STRETCHING (stretching) - a process opposite to compression, occurs as a result of the impact of two or more blunt hard objects on the body in divergent directions. One of these objects is often stationary; it fixes the body or part of it. When stretched with great force, parts of the body may rupture or even be torn off.

FRICTION is the contact (sliding) of part of a blunt solid object or its entire surface with one or another surface of the body along a tangential path, and the object or body, and sometimes both, are in motion.

As a result of friction, skin abrasions are formed, detachment from the underlying tissues, the so-called “filing down” of protruding areas of bones in the joint area.

These mechanisms of action of blunt hard objects are rarely found in isolation. As a rule, we observe a combination of two or more mechanisms acting simultaneously or in very rapid succession, which determines the variety of damage that occurs and its characteristics.

Predominantly anatomical injuries from blunt hard objects

Abrasions

After we have examined the main general issues of forensic traumatology, we can move on to a detailed study of injuries from blunt hard objects. First of all, we will be primarily interested in anatomical injuries, which are the most common object of forensic medical examination for mechanical injuries.

Abrasions represent a violation of the integrity of the epidermis (mucous epithelium) or the epidermis and papillary layer of the skin.

If only the epidermis is damaged, then bleeding does not occur. Such abrasions are sometimes called superficial. If the damage also involves the papillary layer of the skin, in which the vessels are already located, then bleeding occurs (such abrasions are called deep).

Abrasions are caused by the impact of blunt hard objects, and the more prominent the surface of such an object is, the more easily, other things being equal, an abrasion occurs. In some cases, abrasions can be caused by sharp objects, for example, the edge of a knife, with slight pressure and sliding By skin. Such abrasions have a linear shape and are called scratches.

The mechanism of abrasion formation consists of impact, compression and friction.

The shape of abrasions can be varied: it depends on the shape and size of the surface of the traumatic object, the angle at which it acted in relation to the skin. So, if the impact prevailed in the mechanism of abrasion formation, friction was small, a. the angle at which a blunt, hard object acted was close to a straight line, then the shape of the abrasion can more or less completely mirror the shape, size, and sometimes even the relief features of the instrument of injury. If the main mechanism of abrasion formation was friction and advancement of the surface If a blunt hard object presses it on the surface of the skin at an acute angle, then the abrasion takes the form of a strip.

Under the influence of healing, the abrasion undergoes significant changes; it goes through several phases or stages, which are presented in Table 6.

Table 6

ABRASION HEALING SCHEME

The bottom of a fresh abrasion is located at or slightly below the level of intact skin, it is moist and shiny. Then, after the bleeding stops, the abrasion begins to dry out and a crust forms, under which epithelization subsequently begins, from the periphery to the center. When the crust falls off, pinkish-bluish pigmentation of the skin can be seen at the site of the former abrasion. The pigmentation disappears after a few days and “then it is no longer possible to determine the place where the abrasion was located. The healing time of abrasions can vary depending on their location.

According to the severity of the abrasion, the damage is always light and does not cause short-term health problems or minor permanent loss of ability to work.

Abrasions have important forensic medical significance and make it possible to resolve issues important for the investigation and court:

1. The abrasion objectively confirms the fact of mechanical impact of a blunt hard object.
2. The location of the abrasion indicates the point of contact of a blunt, hard object with the skin (impact site).
3. The number of abrasions located in different areas indicates a minimum number of impacts with blunt hard objects (the number of impacts may be greater than the number of abrasions, since some of the blows may not have left marks).
4. In some cases, the shape of abrasions may indicate the shape, size, and sometimes also the relief features of the traumatic object.
5. Based on changes in abrasions during their healing process, the issue of how long ago the injury is is resolved.
6. Sometimes the characteristics and location of abrasions can give rise to assumptions about the type of violence (for example, crescent abrasions on the neck can be formed from the action of fingernails during an attempt to strangle with hands).

Abrasions are often combined with other mechanical injuries - bruises, wounds, fractures, etc. In these cases, the assessment of injuries in a complex allows us to solve important questions about the mechanism and conditions of occurrence of injuries, the nature of the instrument of injury, the lifetime of injuries, etc.

Skin abrasions from blunt objects can also occur posthumously (for example, during careless transportation of corpses). Such post-mortem deposits of the skin have long been called PARCHMENT STAINS. After post-mortem deposition of the skin, the damaged areas dry out; become dense, have a yellowish, and then yellow-brown color. Unlike intravital abrasions, crusts do not form in the area of ​​the parchment stain; on its incision, either no hemorrhage into the thickness of the skin is detected at all, or it is only slightly expressed. Histological examination of skin with parchment spots does not reveal swelling and infiltration, characteristic of intravital abrasions.

BLEEDING

Bruises - hemorrhages in the skin and subcutaneous tissue and in deeper tissues from the impact of blunt hard objects. In some cases, bruises may have a non-traumatic origin - arise from diseases. These are so-called pathological bruises.

The mechanisms of bruising consist of IMPACT, COMPRESSION and STRETCHING.

In size, bruises can be very small (petechiae), small or large, or hematomas (accumulations of blood in limited cavities).

Based on depth, one can distinguish between superficial bruises, which involve the skin and subcutaneous tissue, and deep ones, which also extend to muscles and other soft tissues. The size and depth of bruises are determined by the caliber and number of damaged vessels, the nature of the damaged tissue, the condition of the vessels, the age of the victim, the characteristics of the instrument of injury and the kinetic energy with which it acts.

The shape of the bruises depends on the shape, size and surface relief of the traumatic object. When struck by blunt, hard objects with a limited surface area, the bruise can mirror the shape and size of the object (for example, when struck by a belt buckle). When exposed to blunt hard objects with a predominant surface (board, etc.), bruises often have an oval or round shape, since the area of ​​impact approaches an oval or circle. When struck by objects with a cylindrical surface or close to them (for example, a stick), the bruises take on a peculiar shape: two narrow linear hemorrhages separated by an area of ​​seemingly unchanged skin. This happens because the vessels are more resistant to compression than to stretching; in a narrow zone of impact, the vessels are compressed, and along the periphery they are stretched and torn.

In the area of ​​bruises, after their occurrence and during the healing process, complex biochemical processes occur, in particular, changes in blood hemoglobin, which is not externally manifested in a change in skin color in the area of ​​the bruise (usually they say that the bruise “blooms”). Flowing from damaged vessels, blood accumulates under the skin and, shining through it, gives the bruise a bluish color (hence the “bruise”). When the bleeding stops, the breakdown of red blood cells begins. Under the influence of enzymes, hemoglobin is restored, which gives the bruise a purple color.

Sometimes the process of hemoglobin conversion ends here and the color of the bruise does not change until it completely resolves. This can be observed in areas where there is no subcutaneous fatty tissue, or where there is very little of it (red border of the lips, scalp). This circumstance must be taken into account in order not to make a mistake when determining how long ago the bruise occurred.

Subsequently, hemoglobin breaks down into the protein globin and the coloring substance hematin (heme). Next, hemoglobin is converted into verdohemochromogen, which gives the bruise a greenish color, and then into biliverdin and bilirubin, which have a yellow color and accordingly color the bruise. In bruises that are 5-7 days old, you can simultaneously see yellow, green and bluish-purple (in the center) colors. The bruise gradually fades to match the color of the surrounding skin. The change in the color of the bruise allows us to roughly judge its age, taking into account the size and depth of the bruise.

Sometimes a bruise does not form on the surface of the tissue, but in the depths of it, so it does not become visible immediately, but “appears” after 2-3 days. This should be kept in mind when examining victims, when they insist that they were beaten yesterday or today, but the expert does not establish any traces of damage. In such cases, the witness is recommended to come again in 2-3 days.

As a rule, a bruise forms at the site of impact. However, in some cases, bruises may appear far from the site of impact. For example, with fractures of the base of the skull, bruises may appear in the thickness of the eyelids, the so-called “spectacles”.

Bruising is often combined with other mechanical injuries (especially with such types of injuries as transport, falling from a height, etc.) - abrasions, wounds; fractures.

According to the severity of bruises, as a rule, the injuries are minor and do not cause short-term health problems or minor permanent loss of ability to work. However, in some cases, bruising, if there is a lot of it and if it is large enough in size and depth, can lead to significant blood loss and shock. In these cases, they pose a real danger to life and as such will qualify as grievous bodily harm.

M.I. Raisky cited cases of death from bruising that he observed before the 1917 revolution. It was about horse thieves caught by peasants at the scene of a crime and subjected to beatings during lynchings. There were continuous bruises under the skin, death occurred in the first hours after the injury was caused from acute blood loss and shock.

The forensic medical significance of bruises is approximately the same as abrasions:

1. The location of the bruises usually indicates the place of impact of a blunt hard object -
2. Bruising, if not pathological, is evidence of impact from a blunt hard object.
3. The shape of the bruise sometimes gives an indication of the shape and size of the instrument of injury.
4. The color of the bruise allows us to roughly judge how long ago it occurred.
5. The location and shape of the bruises may presumably provide clues to the nature of the incident. For example, small round bruises, sometimes in combination with linear abrasions on the neck, may indicate the possibility of compression of the neck with hands; multiple bruises on a woman’s inner thighs can occur during attempted rape, etc.

WOUNDS

Damage (separation of the skin) involving at least the entire thickness of the skin is called a wound. There are simple or superficial wounds that involve only the skin, and complex or deep wounds that affect deeper tissues. Wounds that communicate with the cavities of the body or joints are called penetrating.

Wounds can occur from blunt hard objects, sharp objects, or firearms.

The mechanism of formation of wounds from the impact of blunt hard objects consists of IMPACT, COMPRESSION, STRETCHING, FRICTION.

Depending on which of these effects predominates, the following types of wounds from blunt hard objects are distinguished:

• - BRUITED - from impact and compression;
• - TORN - from impact and stretching;
• - BRUISED-TORGED - from impact, squeezing and stretching;
• - CRUSHED - from a very strong blow and compression;
• - SCALPED - (patchwork) - from a blow at an angle to the surface of the body with subsequent stretching.

In addition, BITTED brines are also distinguished from the action of human or animal teeth.

Despite the wide variety of shapes, sizes, and depths of wounds caused by blunt hard objects, they all have their own specific features that allow them to be differentiated from wounds caused by sharp objects or wounds from firearms.

The components of a wound are: edges, ends, walls (planes), bottom.

Although wounds from the impact of blunt hard objects can occur on almost any part of the body, however, other things being equal, they are more easily formed where bone is located close under the skin, primarily on the head. By the way, it is the head that most often becomes the target violent influences.

The shape and size of the wounds depend on the nature of the traumatic surface of a blunt hard object and on the angle of its impact with one or another part of the body.

Thus, when exposed to blunt hard objects with a limited surface, the dimensions of the wounds are less than or equal to the area of ​​contact of the blunt hard object with the surface of the body; if the surface of the object has ribs, then the wounds will be linear (with one edge); L-shaped or U-shaped. A triangular shaped impact surface can cause an angular wound.

If a blunt hard object with a predominant surface was used, then bruised wounds appear, in the center of which the area with the greatest crushing of the tissue can be distinguished, and linear tissue tears can extend radially from the center of the wound. The action of such blunt objects (for example, a board) is characterized by severe bruising and skin aggravation along the edges of the wounds over a significant area.

The dependence of the shape and nature of wounds on the angle of impact of a blunt hard object with the surface of the body is shown in Table 7.

Table 7

DEPENDENCE OF THE FORM AND CHARACTER OF WOUNDS ON THE ANGLE OF IMPACT OF THE SURFACE OF A BLUNT SOLID OBJECT WITH THE BODY

Wounds from blunt hard objects have common features:

• - EDGES of wounds are uneven, crusted, bruising, often detached from the underlying tissues;
• - ENDS of wounds are uneven, rounded, L-, P-, T-shaped;
• - TISSUE in the depths of the wounds are crushed, bruised, there are often bridges between the edges, at the bottom of the wound;
• - BLEEDING from wounds is slight;
• - HEALING - by secondary intention (if there was no surgical treatment of the wounds).

Lacerated and scalped wounds have much in common with the described signs of bruised and lacerated wounds, but in some cases their edges are either without bruising at all, or bruising is observed in small areas.

If the wound is caused by a blunt, hard object with one edge (especially on the scalp), when viewed with the naked eye, it may closely resemble a cut wound: its edges are smooth, its ends are pointed. When examined with a magnifying glass, inverted hair follicles, slight uneven edges, and narrow stripes of skin abrasion along the edges of the wounds become noticeable in the walls of the wound.

When struck by objects with a cylindrical surface, predominantly slit-like or semilunar wounds occur, and their length corresponds to the length of the axis of the traumatic object. The edges of the wounds are uneven, becoming thinner towards the center of the wound, which gives the wound the appearance of a groove, the edges are bruised, bruised, and the bruising is wider, the larger the diameter of the cylindrical blunt solid object.

Wounds from the action of blunt hard objects are of great forensic importance. The presence of a wound confirms the fact of exposure to a blunt hard object. The nature of the wound allows us to judge the mechanism of action of a blunt hard object and its characteristics, the angle and direction of its action and the force with which it acted. The number of wounds indicates the minimum number of impacts from a blunt, hard object.

BONE FRACTURES

Of all the mechanical injuries caused by blunt hard objects, fractures are of greatest forensic importance. This is determined, firstly, by the high frequency of their occurrence; secondly, it is bone fractures that in many cases determine the severity of bodily injury, and, in combination with damage to the brain and internal organs, are the most common cause of death due to mechanical damage. And finally, thirdly, bone fractures contain valuable information for resolving important issues of interest to the investigation and the court (about the mechanism of occurrence, sequence, lifetime, the nature of the instrument of injury, etc.).

Most often, in approximately 70% of cases, fractures of the skull bones occur in forensic medical practice, followed by fractures of long tubular bones, ribs, pelvis, and spine.

V.N. Kryukov, who worked extensively and fruitfully in the field of forensic fractology, gives the following definition of the concept of “fracture”: this is a violation of the integrity (separation) of bone substance within the anatomical part of the bone with the formation of two surfaces that did not exist previously and allow their displacement in relation to each other. each other in two or three degrees of freedom. These are so-called “complete” fractures. In addition to them, there are also “incomplete” fractures or cracks, which represent a violation of the integrity of the bone substance, which does not allow displacement of the separated parts of the bone relative to each other. An example of such fractures is cracks in only one outer or inner plate of a flat bone. In addition, there are also “fractures” - incomplete fractures with separated edges, i.e., allowing displacement of the separated parts of the bones relative to each other in the same degree of freedom. Cracks form in flat bones, breaks - in tubular bones.

According to the place of education they distinguish straight(or local) fractures that form at the site of application of traumatic force and indirect (or distant) fractures that occur far from the site of application of force.

According to the direction of the main lines of fractures, longitudinal, transverse, diagonal (oblique), spiral, ring-shaped fractures and their combinations can be distinguished.

According to the nature of bone damage, they are distinguished: linear, comminuted, perforated, depressed, terrace-like fractures. A combination of these may also occur.

According to communication with the external environment, fractures are divided into open and closed. Clinicians consider open all those fractures in which there is a violation of the integrity of the soft tissue at the site of bone damage, regardless of whether there is communication between the fracture site and the external environment. In contrast, many forensic doctors consider only those fractures that communicate with the external environment through soft tissue damage to be open.

The nature, features, and severity of fractures depend on many factors, the main of which are:

1. The force of impact of the traumatic object.
2. Direction of impact, place of application of force, angle of interaction (impact) of a blunt solid object with the surface of the body.
3. Structural features (general and individual) of soft tissues and bones at the site of impact; availability of clothes and shoes.
4. Properties of a blunt hard object and its traumatic surface.
5. The type of deformation that caused the fracture.

Deformation is a change in shape under the influence of mechanical force. The deformation can be elastic, when after the cessation of the external force, part of the bone acquires its original shape and linear dimensions, and residual deformation, when the shape and linear dimensions are not restored after the cessation of the force. Bone fractures are characterized precisely by residual deformation, when the force of external influence exceeds the strength reserves of the bone and its destruction occurs.

There are five types of deformations that cause fractures, and from each of them, fractures acquire characteristic morphological features:

• 1) SHIFT;
• 2) BEND;
• 3) COMPRESSION;
• 4) STRETCHING;
• 5) TORSION.

These types of deformation can be either isolated or observed in combination (for example, shear and bending, shear and compression, etc.).

SHEAR (cut) is a sharp short-term (within a fraction of a second) impact of a blunt solid object with a limited surface at a right angle with significant force. So, for example, for a long tubular bone to fracture due to shear when hit by a part of a car, its speed must be about 60 km/h.

In a shear fracture, the processes of bone deformation and then its destruction are localized at the site of direct impact of the damaging object. Therefore, shear fractures are always straight (therefore, shear fractures do not occur at the base of the skull, since the base of the skull cannot be the point of application of force). Shear fractures have a transverse or oblique-transverse direction relative to the long axis of the bone. Shear fractures are especially typical on long tubular bones, although fractures from other types of deformation also form on them.

In the second type of deformation - BENDING (sometimes called a bend), two forces directed towards each other at an angle act on the bone. Moreover, if we are talking about a long tubular bone, then one or both ends of it can be fixed. The bone bends, its mechanical stresses change: areas of tension appear on the convex surface, and compression areas appear on the concave surface. Since the bone is much less resistant to tension, it is on the convex surface that a crack appears, which then bifurcates towards the concave surface, forming a splinter. Bending fractures can be either direct or indirect.

During compressive deformation, two forces act on the bone towards each other. In practice, it may be that one force acts on the bone, compressing it, while on the other hand the bone is fixed. Compression deformation for long tubular bones and the spine can be in both horizontal and vertical directions. When compressed in the vertical direction, impacted fractures are formed: areas of stress appear on the outer surface of the bone along its entire circumference, the bone breaks in the transverse direction, and if the compression force continues to act, then longitudinal cracks extend from the line of this fracture, which are indirect fractures. An example is impact fractures of the hips and spine when falling from a height onto straight legs.

With horizontal compression, stretch areas appear on the lateral surfaces of the bone, the bone tube is deformed and local fractures are formed.

Compression deformation on the bones of the skull, pelvis, and ribs occurs in the horizontal direction (and on the skull in the lateral direction). Under the influence of significant force on the skull from front to back or in the lateral direction, when one of the surfaces of the skull is pressed against some blunt object, the skull is compressed, sharply flattened, and its circumference increases. In areas of greatest stretch, located as if along the equator, multiple fractures occur. This will be discussed in more detail in the section on skull fractures.

In a tensile deformation, two forces act on the tubular bone in divergent directions. Often, one end of the bone is fixed. The bone tube, under the influence of stretching, becomes thinner in the diaphysis, and indirect fractures form. Such fractures can be observed, for example, in a railway injury that is not associated with a wheel rolling over a person’s body, when the lower limb is somehow fixed, and the upper part of the tree is captured by part of the moving train.

During torsional deformation, under the influence of two forces acting towards each other, when the bone rotates around its axis, with one end of the bone being fixed, S-shaped, spiral-shaped indirect fractures are formed.

As already noted, with all five types of deformation, compression and tension are observed in different parts of the bone, which have their own morphological characteristics. On the side of the bone that has been stretched, the fracture line is always single, finely jagged, straight, without any chipping elements. Its direction is often transverse, less often longitudinal, diagonal, and spiral. From the ends of such a fracture, 2-3 additional lines of fractures begin, heading towards the compression zone on the opposite surface of the bone and forming an angle open in this direction.

On the compression side of the bone, the fracture line can be single or double; it is uneven, zigzag, more often located obliquely or longitudinally, below or above the fracture line on the tensile side, but never coincides with it. The edges of the fracture are coarsely jagged, uneven, split, and gaping. A loose bone fragment is formed on the compression side. The edges of the fracture are crumbled, one edge is undermined, the other is beveled. Often, additional fractures form on the compression side, the lines of which extend in a perpendicular direction to the main fracture line.

SKULL FRACTURES

Fractures of the skull bones have the greatest forensic medical significance, so we will analyze them in more detail.

Fractures of the skull bones occur either from impact from blunt hard objects, or from compression, or from a combination of both. In accordance with this, skull fractures are formed from shear, bending, or a combination of both, sometimes accompanied by compression deformation.

From shear deformation due to the strong impact of a blunt solid object with a limited surface at an angle close to a straight line, only straight perforated fractures are formed on the bones of the cranial vault, to a certain extent reflecting the shape and size of the impacting surface of the instrument of injury.

When the direction of the impact is not strictly perpendicular, but at a more acute angle, the fractures arise from shear and bending and are depressed or terrace-shaped. Such fractures occur from the impact of blunt objects with a limited surface. In this case, the side of the fracture where the shift took place indicates the place of the primary impact.

Fractures from bending deformation are formed from the impact of blunt hard objects with a rectangular, relatively wide surface, spherical or rounded. If we consider such fractures from the side of the outer plate, we can see concentric cracks that limit the areas of depression in the form of a circle or oval; radial cracks inside this fracture site, extending from the center (the point of contact of the convex surface of the bone with the traumatic object) and not intersecting the concentric cracks, as well as meridional cracks, extending to the sides from the concentric one and spreading to the bones of the vault and base of the skull, if there was a strong impact a blunt solid object of a spherical shape (or close to it) with a large diameter.

From objects with a wide predominant surface, single blows to those sides of the skull that do not have a large curvature cause comminuted fractures.

The skull can be compressed both as a whole and in individual parts by blunt hard objects with a predominant surface in various directions: from front to back (back to front), from the sides, from top to bottom (from bottom to top).

In this case, bone fractures are formed from bending deformation in combination with tensile deformation and, less commonly, compression deformation.

When the head is compressed, direct bone fractures are formed in the places where forces are applied, and indirect ones - at a distance from them (on the vault and at the base of the skull).

Fractures of the skull bones due to compression in the lateral direction.

In these cases, the diameter of the skull between the poles is shortened and lengthened along the equator. At points of compression (force application), the bone plates bend inward, areas of tension appear on the inner plates, and compression areas appear on the outer plates. In areas of greatest stretch - along the equator - cracks appear running in meridional directions, and from them, due to bending of the bones, perpendicular cracks extend in the equatorial direction, which as a result forms comminuted fractures. The same mechanism of fracture formation occurs when the skull is compressed in the anteroposterior direction.

When the skull is compressed from top to bottom, in addition to the described fractures, which are typical for compression of the skull in general, ring-shaped fractures also occur around the foramen magnum, and the shape of such a fracture is closer to a circle, the more vertical the position of the person’s head at the moment of compression. When compressed with a very significant force, cracks may arise from such a ring-shaped fracture, connecting with other fractures at the base of the skull.

Damage to the bones of the skull is usually accompanied by damage to the membranes and substance of the brain, which are more pronounced the more extensive the fractures and deformation of the skull are, which in such cases is the cause of death.

We have outlined the typical features of the formation of skull fractures in general. It should be borne in mind that approximately the same impacts on the same anatomical areas of the skull in different people can cause fractures that differ in severity and some morphological manifestations. This depends on many reasons: the strength characteristics of the various bones of the skull in general and in each person individually; the size and shape of the skull, in particular, on the ratio of the transverse-longitudinal diameter and the combination of altitudinal-latitudinal and altitudinal-longitudinal indicators; on the gender and age of the person, the degree of fusion of the sutures and others.

These characteristics and the features of skull fractures that depend on them were studied in detail by V.N. Kryukov (1986) and his students V.O. Plaksin, I.A. Gedygushev and others.

Fractures of the bones of the spine, ribs and pelvis are also of greater forensic importance, since they are often accompanied by damage to the spinal cord and internal organs, causing danger to life and in some cases ending in death.

SPINAL FRACTURES

Fractures of the vertebrae (body, arches, transverse and spinous processes), as well as damage to the intervertebral discs and ligaments, arise from impact, compression, or a combination of both.

From a direct blow, direct fractures occur; from all other types of impact, fractures are indirect; they are formed far from the place of application of force.

When the spine is struck from behind, fractures occur more often in the thoracic and lumbar regions, less often in the cervical region, since it is easily displaced, which reduces the force of impact. Fractures of the arches are formed, the vertebrae are displaced in the direction of the impact. In these cases, shear deformation acts, and sometimes bending is added to it. If there is a sharp shift of the vertebrae in relation to each other, then damage to the spinal cord may occur, leading to either an anatomical or physiological interruption.

With sharp flexion and extension of the spine, indirect fractures from bending deformation can occur. More often they occur in the cervical region, less often in the thoracic region, and even less often in the LUMBAR region.

The mechanism of occurrence of fractures during flexion of the spine is presented in the following form: with a sharp movement of the spine forward, the posterior ligaments are stretched and torn in the transverse direction, then the interspinous ligaments and ligaments between the vertebral arches, then the dura mater is torn from the posterior surface and, if flexion and the resulting compression continue, compression fractures of the vertebrae are formed. A sort of “mirror” mechanism occurs when the spine is sharply extended.

When the head tilts sharply to the left or to the right, the mechanism of occurrence of fractures is approximately the same, but fractures of the transverse processes are added to the existing fractures. To this it should be added that with sharp tilts of the head and neck to the left and right, along with stretching and rupture of the intervertebral ligaments, ruptures of the intervertebral arteries can also occur, and, as a consequence, the rapid development of basal "subarachnoid hemorrhages, leading to death (V. L Popov, 1988).

When the spine rotates sharply, the cervical region is most often damaged. In this case, torsional and bending deformations occur, unilateral ligament ruptures are observed, and fractures rarely occur.

COMPRESSION of the spine can be observed in both horizontal and vertical directions. In the first case, as a result of compression and bending deformations, to which torsion is sometimes added, indirect fractures of all vertebral formations are formed. With vertical compression, indirect compression fractures are formed.

In order to understand in detail the nature of spinal fractures, and to resolve questions about the mechanism of their formation and the type of impact, it is necessary, when examining a corpse, to remove the entire damaged part of the spine, place it for 2-3 days in a formaldehyde solution and then examine it using one of the methods, proposed by A.A. Solokhin, V.A. Sveshnikov and Yu.I. Neighbor.

Rib FRACTURES

Rib fractures occur from impact, compression, or a combination of both.

A blow from a blunt hard object with a limited surface causes direct fractures, while the inner plate of the rib is stretched, bends inward, and the outer one is compressed. Therefore, an incomplete fracture often occurs - only one internal plate. In complete fractures, damage to the visceral pleura and lung tissue from fragments of the broken rib(s) is sometimes observed. Signs of compression on the outer plate are uneven, coarsely toothed, often chipped edges of the bone; fractures of the cortical layer with a raised free end, which hang over the edge of the fracture in the form of a visor. Sometimes, from the fracture line, which has a transverse or oblique direction in relation to the length of the rib, multiple cracks extend in the direction of the length of the rib. Direct fractures from impacts with blunt hard objects with a limited surface are based on shear and bending deformations.

When struck by blunt hard objects with a predominant surface, fractures are formed due to bending deformation both at the point of impact (direct fractures) and along the area from it (indirect fractures). These fractures can be located along several lines, involve several ribs, and have a transverse or oblique direction. On the compression side, fractures are in the form of a single line; on the tension side, a free bone fragment may form.

When the chest is compressed, due to bending and compression deformation, as well as their combination, in the anteroposterior direction, indirect fractures are formed on two opposite surfaces of the chest along several anatomical lines. The direction of the fracture lines is transverse or oblique, and if torsion is added, then spiral-shaped. Fractures are comminuted in the form of one line on the compression side, and two on the tension side with the formation of free bone fragments.

When studying rib fractures on a corpse, it is recommended that the rib injury is first examined on the spot, then isolated, freed from soft tissue and examined in more detail (by the expert himself or in the physical and technical department of the Bureau of Forensic Medicine).

PELVIC FRACTURES

Pelvic fractures can occur from impact, compression, or a combination of both.

When struck by blunt hard objects with a limited surface, due to shear, bending, or a combination of deformations, direct fractures are formed that are either perforated (in the area of ​​the iliac wing) or linear (in the pubic bone).

When struck by blunt hard objects with a predominant surface, when bending and sometimes torsion deformation is applied, fractures can form both at the site of the force and far from it. Fractures are linear or comminuted, spiral.

When the pelvis is compressed in the anteroposterior and lateral directions from bending, compression, and torsion deformations, both direct and indirect fractures occur, comminuted and multi-fragmented, compression, and spiral.

Particular attention should be paid to the characteristics of pelvic bone fractures in children. In forensic medical practice, such fractures occur quite often. Thus, according to L.E. Kuznetsov (1989), who studied in detail the biomechanics and morphology of pelvic bone fractures in children, they occur in 29.4% of cases of all fatal injuries in children. The pelvis of a child (aged 1-13 years) has a number of significant anatomical and biomechanical features, as a result of which damage to the pelvic bones in children differs from those in adults both in location and in the nature of destruction of bone tissue. In particular, they can occur without disrupting the anatomical continuity of the pelvic ring. This requires freeing the pelvic bones from the periosteum when examining injuries on a corpse. In case of fractures of the pelvic ring with a violation of its anatomical continuity, destruction, as a rule, occurs at the border of bone and cartilage tissue.

Similar features of pelvic bone fractures in adolescents were established by research by Yu.A. Solokhin (1985).

Summarizing everything that has been said about bone damage from blunt hard objects, we can draw a general conclusion that knowledge of the mechanisms of occurrence and morphology of a fracture makes it possible to resolve issues important for the investigation and court.