Characteristics of the strangulation groove. Characteristics of the strangulation groove Strangulation groove when hanging
Types of mechanical asphyxia. Depending on the causes of occurrence, the following are distinguished:
1) from compression: strangulation (from compression of the neck organs), - hanging, strangulation with a loop, strangulation by hands;
2) compression (from compression of the chest and abdomen with solid objects and loose substances);
3) from obturation;
4) from closing the airways;
5) from blockage of the respiratory tract by soft and hard bodies, bulk substances and liquids.
Strangulation asphyxia (from compression of the neck organs) includes three types: hanging, strangulation with a noose, strangulation by hands.
Squeezing the neck with a noose under the influence of the weight of the body or part of it is called hanging. Only the head's gravity is sufficient for hanging.
From the impact of the loop, an imprint is left on the neck - a strangulation groove. The groove appears on the corpse slightly deepened, purple-cyanotic from the transmission of muscles. If the loop is uneven or folded (from a rolled towel) or patterned (from a braided rope or scarf), folds and patterns are imprinted on the leather. When examining the strangulation groove, its following properties are determined: location, direction, the number of individual elements of the groove, which depends on the number of revolutions of the loop (between the individual elements of the groove, ridges of restrained skin are formed). It is necessary to distinguish cases of double, triple, and so on grooves from those cases when there are several separate grooves caused by different loops or one, but not simultaneously. These individual furrows are usually unconnected and often run in different directions. The closedness or discontinuity of the furrow, its width, depth, relief, density are noted. In putrefactively changed corpses, the neck circumference increases due to putrefactive emphysema. The loop mark is the more pronounced, the stiffer and thinner the material. The skin dries out from the compression and sedimentation of the epidermis with a loop, sufficiently firm strangulation grooves are formed. They protrude into soft tissues, are dense to the touch, brownish in color, reminiscent of parchment, often with a clear deposition of the stratum corneum. The strangulation groove is well expressed in the part opposite to the node, and may be absent closer to it.
When the neck is compressed, muscle weakness and loss of consciousness quickly occur, so the possibility of self-rescue when hanging is practically excluded.
The mechanisms developing when hanging functional disorders, leading to further death, include the cessation of air access to the lungs; compression of the vessels of the neck, especially the jugular veins and carotid arteries; a sharp increase in intracranial pressure; compression of the nerve trunks; compression of the carotid sinus node, located at the site of the division of the common carotid artery into external and internal.
31. Features of the inspection of the scene. Questions resolved by forensic medical examination
Inspection of a corpse at the scene when hanging has a number of features.
In most cases, hanging occurs in a position where the feet are not touching the ground, but it can occur in any other position of the body. The more pretentious the posture, the more reason to assume the imposition of the loop with your own hand.
To find out the possibility of self-hanging in these conditions helps to inspect the environment around the corpse. They pay attention to the objects of the environment that a person could stand on to strengthen the noose (stools, boxes); they may have footprints, soiled shoes.
Measure the body length of the corpse from the area of the soles to the tips of the fingers of the raised hands; the distance at which the hinge attachment is located from the floor, from the detected stand or any elevations.
Loops are closed sliding, when the loop is tightened through the knot under the weight of the body; closed fixed, when the knot is tied so that it does not allow the free ends of the material used to make the loop to slide; open loops when there is no knot at all. Loops can be single, double and multiple. When examining a corpse, attention is paid to cadaveric phenomena and the degree of their severity. The location of the cadaveric spots helps to judge the position of the body after death. Cadaveric spots with an upright position of the body are located on the lower extremities, hands, forearms. It is necessary to pay attention to the position of the tongue. During strangulation, it often protrudes from the oral cavity and is bitten. The pressure of clothing may remain on the skin, sometimes mistaken for a strangulation groove.
When the position of the body changes, the cadaveric spots in the first stage of their development also change their location: in the original place they disappear and appear in other areas according to the new position of the body. When the corpse is in the loop for more than 8 hours, if the posture of the corpse is changed, the cadaveric spots on the limbs may only slightly fade, and cadaveric spots will appear in other areas, but at an earlier stage.
The main questions to which it is necessary to find an answer to the forensic medical examination are what are the causes of death and a noose was imposed on the neck in vivo or posthumously.
These questions are resolved on the basis of identifying the features of the strangulation sulcus. Hanging is characterized by the presence of a strangulation groove obliquely ascending towards the node with an uneven deepening in various areas, which is interrupted at the site of the node. The next questions that arise in the course of the investigation are: what are the properties of the noose, the noose was put on by one's own or an unauthorized hand, and how long the body was in the noose.
32. Strangling with loops. Strangulation by hands. Characteristic signs found on the body of the victim
Squeezing the neck with a loop thrown over it (a kerchief and other similar objects), which is tightened not by the weight of the body, as when hanging, but by your own, extraneous hand or some moving mechanism, is called strangulation by the loop.
This is the main difference between strangling with a loop and hanging.
The loop can be pulled tightly around the neck and tied in a knot at the front or back, less often it is tied at the side. Instead of a knot, a twist, a stick or other elongated object inserted into a loop can be used, with which it is tightened. Sometimes a loop is thrown around the neck of a sitting or lying person and pulled at the ends of the loop from behind, without tying a knot, squeezing the anterior-lateral surface of the neck.
For cases where a loop is applied by an outsider's hand, traces of struggle and self-defense are characteristic in the form of injuries of a different nature on the victim's clothing and body. The role of the loop can be played by some items of clothing (ties, scarves, scarves, belts, etc.), the ends of which sometimes fall into rotating or moving parts of the mechanism of machines.
In contrast to hanging, the strangulation groove, when strangled by a loop, most often has a horizontal direction, covers the entire circumference of the neck, that is, it is closed, and is expressed evenly throughout. On the front of the neck, it is usually located at or below the thyroid cartilage. In the course of the strangulation groove, with strong compression by the loop in the subcutaneous tissue and muscles, hemorrhages are noted. More often than hanging, there are fractures of the horns of the thyroid cartilage and other cartilage.
There are cases when the victim is deprived of life by strangulation with a loop, and then suspended in the same loop. In this case, two strangulation grooves can form on the neck, diverging at an angle.
Strangulation by hands. The mechanism of death when strangled by hands is closest to the mechanism of death by strangulation by a loop. Hand strangulation is rare. It is always due to the influence of an extraneous hand, since weakness and loss of consciousness develops very quickly.
The action of an extraneous hand is due to the compression of the organs of the neck. This constriction is accompanied by a struggle. Typical injuries in the occipital region occurring when the occiput is pressed against hard objects. When the chest is compressed by the knee of the attacker while pressing the victim's body to the ground, the floor, and so on, injuries are noted in the form of bruises and even fractures of the ribs. The general signs of asphyxia are manifested by symptoms of stagnation on the face and neck in the form of cyanosis and minor hemorrhages.
When hanging, death occurs due to the compression of the neck with a noose tightened by the weight of the body.
Hinges by the mechanism of their tightening on the neck, they can be motionless and sliding.
The loop has a knot, a ring and a free end. If the knot is tightly tied and the ring does not change its size, then such a loop is called fixed, or fixed. More often the loop at one end has a small "eyelet" - a knot, the other free end is threaded into it, as a result of which an easily movable loop of the loop is formed. Such a loop is called a sliding loop.
Depending on the material used for the hinges, they are divided into rigid ones (wire, electric cord, etc.); semi-rigid (belts, thick and coarse ropes) and soft, made of a wide soft material, such as towels, sheets, scarf.
According to the number of revolutions, the loops around the neck are divided into single, double, triple and multiple.
In all cases of hanging during the inspection of the scene of the incident, the loop and its knot should be preserved, since the loop material, the way of tying it in some cases can help establish the profession of the victim or killer (weaver, sailor, fisherman, etc.).
When an external examination of a person who died from hanging or strangulation with a noose, a characteristic and reliable sign is a depressed mark on the neck - strangulation groove.
Rice. nineteen... Typical (A) and atypical (B) loop overlapping
When a strangulation groove is found, it is necessary to pay attention to its general appearance, location and direction. By these signs, one can judge the nature of the compression of the neck that caused death (hanging or strangulation with a noose). The direction of the furrow depends on how the loop is applied to the neck. When hanging, the loop can be placed in a typical and atypical position. A typical strangulation groove is considered when the loop knot is at the back of the head. With an atypical strangulation groove, the loop knot is located under the chin or on the side (Fig. 19).
Rice. 20. Self-hanging. Rigid strangulation groove
When hanging, the strangulation groove is always directed obliquely - from bottom to top. This is due to the fact that one part of the hinge (free end) is strengthened by some object (nail, door jamb, branch, etc.), and the other, in fact, the hinge itself, is carried down by the weight of the body. In this case, the greatest indentation of the groove is formed on the side of the loop opposite the node, that is, in the place of the greatest pressure on the neck.
The strangulation groove can be closed when both ends of it converge at the point where the loop knot was located, or open when the ends do not close with each other.
Depending on the material of the loop, the furrow can be hard, soft or transitional. A rigid strangulation groove is formed when a loop of dense material with a small cross-section is applied (twine, wire, electric cord). It is always well expressed, depressed, has a parchment appearance, is dark brown in color, and is dense to the touch (Fig. 20). On corpses and in persons released from the noose and survivors, such strangulation grooves persist for a very long time.
Soft furrows are indistinctly expressed, they look like wide, pale bluish, slightly depressed stripes. They are unstable and disappear relatively quickly.
Transitional, or mixed, strangulation grooves are a combination of the first two.
The strangulation groove is a negative imprint of the loop material, reflecting its characteristic features: width, presence of nodes, etc., and the more pronounced the longer the corpse was in the loop (Fig. 21).
It is very important for the authorities of the preliminary investigation to establish whether the furrow was formed during the life of the victim or posthumously, since murders with the subsequent hanging of the corpse to simulate suicide are known. The intravital strangulation groove is pale, anemic due to squeezing out of blood vessels. Above and below the furrow, the vessels are dilated and overflowing with blood, in places small hemorrhages are found. The strangulation groove, according to the number of loops on the neck, can be single, double and multiple. In these cases, raised skin ridges are formed between its turns. From compression and rupture of small vessels in these rollers, punctate hemorrhages occur - this is an almost indisputable sign of lifetime. However, sometimes death in the loop can occur very quickly from heart paralysis, and then there may be no blood filling of the vessels and hemorrhages in the sulcus region.
Rice. 21... Self-hanging. Strangulation groove from the loop of the belt, stitched with patterns
In cases where the corpse of a person strangled by a noose is then suspended in order to simulate suicide, two strangulation grooves form on the neck - one of them is horizontal, lifetime, the other oblique, formed posthumously.
To establish the lifetime of the furrow, it must be examined in transmitted light. For this, the skin with the strangulation groove is separated from the soft tissues and viewed into the light. If the groove is in vivo, then dilated and blood-filled vessels, and sometimes small hemorrhages, are visible along its edges. Along with the study in transmitted light, you can also use a binocular stereoscopic microscope; pieces of the strangulation groove must be examined histologically.
In addition to the strangulation groove, there are other characteristic signs of death from asphyxia. If the corpse hung in the loop for a long time, then the cadaveric spots are most pronounced on the lower parts of the body and lower extremities. Sometimes, against the background of spots, punctate hemorrhages are visible. The forearms and hands have a bluish tinge. In some cases, compression of the letley's neck is accompanied by damage to the larynx: more often fractures or fractures of the large horns of the hyoid bone and the upper horns of the thyroid cartilage are observed. Due to the pressure of the loop, hemorrhages occur in the muscles of the neck. Hemorrhages and even muscle tears may occur at the site of attachment of the sternoclavicular muscles with the formation of small blood clots, which undoubtedly indicates that these injuries arose in vivo. Due to the strong stretching of the neck by the weight of the hanging body, the carotid arteries are simultaneously stretched, which leads to a transverse rupture of their inner membranes below the loop. At the same time, an accumulation of coagulated blood can be seen between the stratified membranes. This sign indicates the survival of the damage, but it does not always occur.
It is very important for the investigating authorities to establish whether there are any injuries on the corpse.
A forensic expert in such cases must determine the nature of these injuries - intravital or posthumous - and how they were caused.
Rice. 22. Hanging on the collar of clothes. Alcoholic intoxication. Accident (personal observation)
In most cases, hanging is suicide, but accidents and even murders are possible. In case of suicide, the body of the hanged person during convulsions may hit solid objects located nearby, for example, protruding parts of rooms, door frames, metal parts of stairs, knots of wood, etc. In these cases, the damage is superficial and is located on protruding parts of the body - on the nose , chin, on the hands. When self-hanging, more serious injuries can be detected, up to cut and stab wounds, which were inflicted with the intent of suicide before being hanged. This is often seen in mental patients.
When killing by hanging, damage to a corpse is of a lifetime nature. In such cases, as a result of struggle and self-defense, hemorrhages and abrasions occur on the arms, neck, face, chest. Cases of murder and without any damage are possible, when a loop is thrown around the neck by deception or during sleep, and its free end is quickly fastened to an object.
It is almost impossible to decide whether there was a murder, an accident or a suicide by the nature of the damage alone. It is necessary to carefully examine the scene of the incident, its environment, posture and clothing of the hanged man, the nature of the noose and knots, as well as all changes on the corpse.
The circumstances of the hanging. In most cases, self-hanging is done by persons who are mentally unstable or in a state of alcoholic depression. There may be cases of school-age children committing suicide on the basis of various childhood experiences and other motives.
As already noted, when hanging, there can be cases of murder by deceiving a noose around the neck of a physically healthy person or in a state of sleep. Possible murders by hanging the sick, physically weak and persons in a state of severe alcoholic intoxication. The presence of a large amount of alcohol in the internal organs at death from hanging may indicate murder, since in a state of severe alcohol intoxication, such persons not only cannot resist, but are also unable to self-hang themselves.
Rice. 23. Self-hanging: legs bent, touching the ground
Accidental self-hanging can result in imitation of suicide or its simulation.
Hanging as an accident is rare. Its victims are mainly small children: a child sticks his head between the rods or into a torn bed net, in which his neck is pinched, loses consciousness and dies from asphyxiation. A similar death due to accidental pressing of the neck against any narrow object occurs in adults who are intoxicated. In our practice, there was a case when a drunk sat down on the steps of the porch, and hung on the railing! - rope reins twisted several times, into which he stuck his head, and
asleep. Due to the pressure of the neck on the reins, self-hanging and death occurred,
In another case, a man in a state of intoxication, wanting to warm up, sat down on a stool by the oven door and, falling asleep, caught the protruding end of the door latch with the collar of his jacket. Death came from the collapse of the neck by the collar of clothing (Fig. 22),
Rice. 24. Paired self-hanging
Poses of the hanged in particular, suicides, are very diverse: the hanged can hang freely in the noose; the head can be in a loop, and the legs, in a bent or bent position, rest on the floor, on the ground (Fig. 23). Suicides can be in various positions: standing on their feet, kneeling, reclining or lying on the bed, while the free end of the loop is attached to the headboard or other object. Sometimes a suicide binds his legs or arms, or both, before hanging himself, putting on a noose. There are also paired suicides, when a man and a woman commit suicide in one loop (Fig. 24).
A strangulation groove is a trace of compression of a loop or a blunt hard object of the neck skin. The furrow is formed by the pressure of the loop material on the skin and underlying tissues. Sloughing of the surface layers of the skin (epidermis) occurs, after removing the loop, the damaged areas of the skin quickly dry out and thicken.
The severity of the strangulation groove depends on the material from which the loop is made and the degree of damage to the surface layers of the skin (epidermis). A rigid loop always forms a deep groove, a semi-rigid one is deeper than a soft one with well-defined borders, a soft loop gives a weakly expressed strangulation groove with indistinct borders and differs little from the usual color of the skin.
When describing the strangulation groove, indicate its localization (in which part of the neck), the structure of the groove (single, double, etc.), display of the relief of the material, closed or open (in the occipital region) direction, width, depth, density, features of the edges and the bottom of the groove, the presence or absence of hemorrhages in the region of the groove and its other individual characteristics and properties.
46.4. Signs of hanging when examining a corpse:
46.4.1. When examining a corpse externally in the case of hanging, along with general asphyxia, there may be a pinching of the tip of the tongue between the teeth and protruding from the oral cavity.
Features of the strangulation groove when hanging:
strangulation groove located more often in the upper part of the neck, above the thyroid cartilage;
has an oblique ascending direction from front to back;
not closed, the upper edge of the furrow is usually undermined, and the lower edge is beveled.
Hanging upright cadaveric spots located on the lower torso, limbs and hands.
On the skin of a corpse, in addition to the strangulation groove, various injuries are possible that could occur during the period of seizures and must be distinguished from injuries that could arise as a result of struggle and self-defense.
If the loop tightly covers the neck, then the strangulation groove will be closed; when hanging in a horizontal or semi-horizontal position, the strangulation groove may be horizontal.
46.4.2. When examining a corpse internally
Hemorrhages in the subcutaneous fatty tissue and muscles of the neck along the strangulation groove, in the inner legs of the sternocleidomastoid muscles of the neck, fractures of the cartilage of the larynx and horns of the hyoid bone, transverse ruptures of the inner lining of the carotid arteries (Ammyus sign) and general fixation signs characteristic of internal examination corpse.
46.5. Intravital and postmortem strangulation groove
A strangulation groove can also form posthumously, i.e. when a corpse is suspended in order to hide the trail of a crime. Therefore, it is important to establish whether the strangulation groove has an intravital or posthumous origin.
Intradermal strangulation groove has intradermal hemorrhages along the strangulation groove (more often in the bottom, lower edge and intermediate ridge), hemorrhages in the subcutaneous tissue, neck muscles, according to the course of the strangulation groove.
The postmortem strangulation groove is pale, poorly expressed, there are no hemorrhages in the area of the strangulation groove.
Hanging happens as the most common method of suicide, hanging during murder occurs in investigative and expert practice extremely sharply, hanging as a result of an accident is observed in 1% of cases of the total number of hangings, simulation of hanging - hanging a corpse in order to conceal the murder.
The strangulation groove is a grooved depression with a bottom, walls, upper and lower edges (ridges). Sometimes, in the presence of several pressing elements, intermediate rollers are also observed.
Signs of a strangulation groove when hanging:
1. Located in the upper third of the neck (usually between the thyroid cartilage and the hyoid bone).
2. Has an oblique ascending direction towards the node.
3. Unevenly expressed.
4. An open groove (between its ends, an interval of intact skin is determined, corresponding to the place of loose contact with the loop material).
5. Sometimes when separating a skin flap in the projection of the SB, on its inner surface, the so-called "internal" or "silver" strangulation groove (Casper's sign) is determined, which is a whitish silvery strip, which can be even in the absence of an external SB.
6. The upper edge of the furrow is undermined, the lower edge is beveled.
The strangulation furrow should be well studied and described according to plan:
1. Location of the furrow(can be at different levels of the neck: in the upper, middle or lower third, above or below the thyroid cartilage).
In addition, it is necessary to indicate the exact location of the SB on all surfaces of the neck. In this case, the location of the groove relative to the anatomical landmarks should be indicated. On the front surface of the neck - relative to the upper edge of the thyroid cartilage, on the lateral surfaces - it is necessary to indicate the distance from the upper edge of the strangulation groove to the angle of the lower jaw and to the apex of the mastoid process. On the back surface - the distance from the upper edge of the SB to the border of hair growth or the middle of the external occipital protuberance is indicated.
3. The presence and severity of ridges. Always between the individual elements (depressions) of the strangulation groove, rollers are formed from pinching the skin, narrow or wide, according to the width of the gap between the whorls.
4. The width of the groove on each surface of the neck. It depends on the width of the buttonhole. It should be remembered that the width of the furrow does not always correspond to the true width of the loop. This applies primarily to soft hinges. For example, a rope loop or a towel loop can have different thicknesses, which is reflected in the loop width.
5. The depth of the furrow on each surface of the neck. Typically dependent on loop thickness and gravity. The narrower the loop, the greater the body weight and the duration of the hovering, the more favorable the conditions for drying and compaction, the deeper and more pronounced the strangulation groove. Wide soft loops form wide, pale grooves, sometimes poorly visible, or generally invisible to the eye.
The depth of the strangulation groove on the corpse does not always correspond to the depth of the groove on the neck during hanging. In the latter case, the furrow is, of course, deeper, and after removing the loop, the skin on the corpse is somewhat leveled.
6. The bottom of the furrow... It is described on each surface of the neck with an indication of its density and color.
The density of the furrow may not differ from the density of the surrounding skin (soft loops), or, conversely, it can have a parchment density due to sloughing of the surface layers of the epidermis, followed by drying (rigid and semi-rigid loops). In the first case, the furrow has a pale pinkish-yellowish color, in the latter it is yellow-brown or even dark brown.
7. Presence of hemorrhages, abrasions, fibers or microparticles of the loop material along the strangulation groove. To detect particles of material, the loops are examined by the SB using an operating microscope or a magnifying glass. If necessary, microparticles are removed with adhesive tape, applying it to the furrow. The need for this arises in the case when the loop was removed before the arrival of the investigator or expert and you need to answer the question of what the loop was made of. In this case, you should also carefully examine the palmar surfaces of the corpse's hands, on which fibers and microparticles of the loop material can also be found.
In addition, during external examination of the corpse, it is necessary to measure the neck circumference at the level of the strangulation groove (to determine the degree of compression of the neck by the loop) and the length of the body with the right arm extended upward (to confirm or refute the possibility of self-hanging).
After studying and describing the strangulation groove, it is photographed with a scale on different surfaces of the neck.
Signs of lifetime hanging
One of the main questions in the study of a corpse removed from the loop is to establish the intravital or posthumous origin of the strangulation groove.
The presence of a groove in itself does not mean that death occurred from hanging, for a corpse may have been hanged, and a typical strangulation groove may form on its neck.
Signs of a lifetime of hanging include:
1.Brown shade strangulation groove, indicating the presence of intravital sedimentation.
2.Hemorrhages along the strangulation groove or in rollers of strangulated skin. For this, the skin is removed from the SB area. Moreover, this must be done before opening, tk. an incision in the skin leads to the leakage of blood from the vessels and saturation of it with the skin, PZhK, muscles and creates a picture of intravital hemorrhages. The skin for examination should be taken from an area outside the cadaveric spot. In this case, the removed piece of skin must include the upper and lower ridges of the groove and be limited from above and below the unchanged skin. The edges of the furrow should be marked; for this, a piece of skin should look like a trapezoid, the smaller base of which corresponds to the upper edge, and the larger one corresponds to the lower edge of the furrow.
Further produce Bocarius test... The PFA is carefully separated from the taken piece of skin, a piece of skin is placed between two glass slides, slightly squeezing it, and examined in transmitted light. At the same time, attention is paid to the presence of dilated small vessels and hemorrhages at the edges of the groove and the absence of these changes in the bottom area.
A similar examination of the removed skin flap can be performed using a stereoscopic microscope. In this case, the difference in the blood filling of the vessels of the upper and lower ridges is clearly visible. Venous congestion is noted in the upper ridge and arterial in the lower ridge.
Hanging is called squeezing the neck with a noose drawn by the weight of your entire body or part of it.
The tool of injury is most often a typical loop. A loop is a ring with one fixed end. Along with this, in practical work, there are atypical loops, which are forks of trees, backs of chairs, etc., on which the neck presses with the weight of the entire body that has sunk or just a tilted head.
According to the material, the loops are divided into soft (towels, ties, scarves), rigid flexible (semi-rigid belts, ropes, cords, cables), rigid inflexible (rigid), atypical (forks of trees, edge of a board, forearm).
The loop consists of a knot, ring, lead and root ends. The root end is an end fixed to the object, not used when knitting a knot, located opposite the running end. The running end is a loose free end in the hands, with which they begin to move when knot is knitted and form a knot. Knot - the place where the ends of the loop are tied, or the running end is tied to the branch of the root end, or the root end is tied to some object. Semi-knot - a single overlap of the running and root ends of the same rope, etc. or two ends of different ropes. A running branch departs from the node, passing into the root, threaded into a movable or fixed node. Forming a ring, the root branch ends with a free end, attached to a firmly fixed object (Fig. 267).
Depending on the design of the knot, the loop can be movable (sliding or noose) and fixed.
Many types of loops and knots are typical for certain professions and specialties (marine, rigging, fishing, weaving, firefighters, mountaineering, used by special services, etc.). According to the loops and knots, the forensic examination establishes the personality and professional skills of the person who tied them, identify the corpse of an unknown person, solve a crime. Loops (Scheme 29) and knots (Scheme 30) encountered in practice are classified according to various criteria.
The design features of the knot already at the scene of the incident make it possible to put forward a version of the profession of the person who tied it, to narrow the circle of suspects and reduce the time of their search.
The loop device affects the appearance and severity of certain signs. In practical work, hanging in sliding loops is most common.
A slip loop is a loop whose knot allows the movement of the loop branch and the change in the diameter of the ring around the neck. It is formed by threading the free end into the hole in the knot, buckle, twist and fixing it motionlessly. Pressing on the lower part of the loop causes the branches to move, change the diameter and tighten around the neck, accompanied by full coverage of the neck. The knot of such a loop can be located on various surfaces of the neck. In this regard, a distinction is made between the typical and atypical arrangement of the node.
Such localization of the loop is considered typical, when the front part of it presses on the neck above the thyroid cartilage, the lateral parts of the loop go around the corners of the lower jaw and the mastoid processes, rising to the external occipital protuberance at an angle, forming a tightening knot. The atypical loop knot is located on the front of the neck under the chin. N.S. Bockarius (1915) and V.V. Tomilin (1978) refers to the atypical location of the node on the lateral surface of the neck, in the area of the ear, the angle of the lower jaw, the mastoid process, and N.V. Popov (1946) and A.A. Matyshev (1985) - its localization to the side (Fig. 268).
Loops are closed and open (fig. 269).
Closedloops contact with all surfaces of the neck (Fig. 270). They can be closed sliding and closed fixed. A closed fixed hinge is a hinge whose knot does not allow a change in the diameter of the ring. In these loops, the ring is tied with a fixed knot by the running and root ends.
The sliding loop and the closed fixed loop are quickly tightened by the weight of the body and do not slip, since the chin, the angles of the lower jaw, the mastoid processes, and the external occipital protuberance interfere with this.
Open loop- this is a loop that does not contact all adjacent surfaces of the neck Open loops are typical and atypical The first ones have all the components of the loop and are a ring with ends tied in one place and strengthened by putting it on a fixing object The head passes the lower part of the ring The lower part of the open loops press the front of the neck (larynx and trachea), and the chin and the corners of the lower jaw prevent the head and neck from sliding out of the loop. The knot of such a loop is usually attached to an object.
Atypical hinges do not have major design features (rings, knots, ends). Hanging is carried out by pressing the front, side or front and side surfaces of the neck to the crossbar, the edge of the board, the crossbar between the legs (prong) of the chair, in the fork of the tree.Open atypical fixed loops squeeze the neck from the front from the sides or from the front and sides, depending on the angle of branching of the branches of the tree.
The hinge material, method and location of attachment are extremely diverse. They can be made of various materials and can be attached to any object that allows you to fix the free end of the loop. The density of the material and the design of the loop affect the relief of the groove (Fig. 271), and its flexibility contributes to a better coverage of the neck with the loop.
Loops made by tying different materials are rare. Such loops and knots allow one to judge the profession of a person, and the method of tying a knot about the mechanism of hanging.
To carry out the hanging, it is necessary to fix the root end of a typical loop motionlessly, make a ring, a knot, fix the running end and put the ring on the neck, change the position of the body or articulation and go down. The posture and articulation are determined by the height of the loop attachment, the absence or presence of a fulcrum, stretching the loop material, neck, and spine. In this regard, hanging can be complete, or free (when a person hangs without touching the fulcrum with his feet), and incomplete, or not free (individual parts of the body touch surrounding objects, and the legs are in contact with the fulcrum). The presence of this or that posture affects the rate of death, the severity of certain signs.
In practical work, incomplete hovering is most often observed, which causes a variety of postures: standing, sitting, kneeling, on the buttocks, lying, etc. (fig. 272).
Loop tension with full and partial hover is always directed upwards, so the loop is displaced to the top of the neck and is positioned in an oblique ascending direction. In those who hanged themselves in the supine position, the loop is localized in the upper third of the neck and has an oblique ascending direction, in the middle third it is horizontal, in the lower third it is oblique, which allows differentiation of hanging with strangulation by the loop.
The sequence of the loop on the neck with a typical knot location . In the vertical position of the hanging and typical localization of the node, the loop, usually sliding up to the hyoid bone, squeezes the neck between the upper edge of the thyroid cartilage, the larynx and the hyoid bone. Its large horns are pressed against the spine, displacing the root of the tongue back and up, thereby pressing it against the back of the pharynx and the soft palate, almost completely closing the lumen of the airways, and makes it difficult or completely stops the access of air to the lungs from the nose or mouth (Fig. 273 ).
Compression of the lateral surfaces of the neck by the branches of the loop causes compression of the carotid arteries, which leads to acute oxygen starvation, and compression of the jugular veins disrupts or completely stops the outflow of blood from the cranial cavity and causes venous congestion. Intracranial pressure rises rapidly, especially sharply increasing when the carotid and vertebral arteries are not fully compressed, through which blood continues to flow to the brain, squeezing the cortex and vital centers of the brain. The medulla oblongata is stretched, the brain stem or branches of the vagus nerve are irritated. Loss of consciousness quickly sets in and typical asphyxia develops. Loop compression of the neck and stretching by the descending body of the vagus and sympathetic nerves, branches of the laryngeal nerve and sometimes the carotid sinus can cause temporary respiratory arrest and primary cardiac arrest or shock. In such cases, death may occur before the development of typical signs of asphyxia.
The sequence of the hinge in the lateral position knot. The loop, squeezing the neck, shifts the larynx towards the node, and the root of the tongue, pushing back and to the side, closes the entrance to the pharynx, in contrast to the displacement of the tongue in the typical location of the node.
Loop sequence for atypical (anterior) placement knot. The upper part of the loop tilts the head back, as a result of which the upper part of the cervical spine protrudes forward, and the back wall of the pharynx approaches the root of the tongue, pushed back by the loop, and blocks the path of air, which can cause asphyxiation. In addition, other tissues and organs are compressed and stretched. Depending on the location of the loop, there may be no airway closure. In these cases, death is caused by compression of the neurovascular bundles of the neck (carotid arteries, jugular veins, vagus nerves).
The greatest pressure due to the peculiarities of the loop and the surface of its coverage, the neck experiences on the side opposite to the knot. The wrap-around position of the loop exerts almost the same pressure on the entire surface of the neck, which is observed in cases of hanging in a tightening double or triple loops.
From the action of the loop, a trace remains on the neck, called strangulation furrow(fig. 274). It arises from pressure, sliding friction and squeezing of the neck with a noose, or only squeezing, being the main sign of hanging.
Mechanogenesis of the strangulation groove is determined by the loop device, its contact surface, the sequence of movement of the whole body in the loop or its parts.
Under the influence of the gravity of the body, typical sliding and motionless closed loops with full and incomplete hovering, tightening, squeeze the neck at the place of primary contact. Moving under the influence of the gravity of the body, the loop settles the skin of the neck from the place of compression to the place of the final movement of the body, where it squeezes the skin again. Compression flattens the skin, and sliding friction peels it off, as a result of which the skin becomes thinner, loses moisture and dries up. Depending on the stiffness and width of the loop, more or less deep and wide, hard or soft furrows appear.
Under the influence of the gravity of the body, open loops, unlike sliding and motionless closed ones, only squeeze the neck, as a result of which the skin flattens, loses interstitial fluid and dries up.
The strangulation groove, representing an imprint of the contacting surface of the loop, conveys its features, allows one to judge the width, relief and material of the loop.
In the strangulation groove, a bottom, edges, an intermediate roller or rollers are distinguished. They can run either parallel to each other, or at an angle to the edges, or intersect each other.
Describing the strangulation groove, it is necessary to reflect its following properties.
Location - the surface of the neck, the level of the lowest and highest position of the groove, the location of branches from fixed landmarks on both sides (the corners of the lower jaw, the attachment points of the auricles, but not the lower edge of the earlobes, since the latter can be lengthened by wearing earrings).
For hanging, the localization of the groove in the upper third of the neck is typical. However, in victims with a pronounced thyroid cartilage ("Adam's apple"), protruding goiter or packets of enlarged glands when hanging in a horizontal or close position, in an atypical open loop, it can be located below the thyroid cartilage, which must be remembered when differentiating hanging with strangulation loop.
The direction of travel of the branches is along the surfaces of the neck from the lowest to the highest position.
The level of the groove on the neck and the direction of the course of its branches make it possible to judge the position of the body both with full and incomplete hovering.
The number of individual elements of the groove is determined by the number of loop revolutions and their relative position. The strangulation groove can be single, double, triple, multi-turn, multiple, parallel or intersecting. Sometimes a low loop in the process of hanging, during convulsions, an unsuccessful attempt to hang, as well as when strangling with a loop followed by hanging a corpse, tightening, moves upward, forming two grooves, between which there is an abrasion with displaced epidermis flaps Usually the upper groove formed by the last , it goes deeper. When the upper turn of the loop is applied to the lower one, and not to the skin, one depression can be obtained.
Depending on the design features of the hinge and the number of revolutions, intermediate rollers can occur, causing pinching of the skin corresponding to the width of the contacting part of the hinge.
The closure of the groove is due to the pressure of the loop along the entire circumference of the neck, the structure and its diameter, mobility, and the size of the node. In closed furrows, both branches converge in the region of the node, in unclosed ones, they do not close.
The width of the furrow depends on the width and thickness of the loop, uneven pressure on the neck, and the hanging mechanism. The different furrow widths give rise to suspicion of the use of multiple loops.
The depth of the groove is determined by the thickness of the loop, the force of gravity, the material of the loop, the position and posture of the victim, the presence of soft pads under the loop.
The severity of the groove is determined by the body weight, design, material of the loop, the location of the knot on the neck, and the time the corpse stays in the loop. The groove is most pronounced on the surface of the neck, opposite to the direction of the loop tension.
The groove relief reflects the features of the loop, knot, loop thickening, twisting, loop material.
The density of the groove is determined by the material of the loop, its size, drying and evaporation of interstitial fluid from the surface of the compressed and displaced epidermis, the type of hanging.
Rigid and semi-rigid loops form deep dense grooves with clear edges and pronounced sedimentation, and soft loops - superficial pale soft grooves with indistinct boundaries.
Double, triple, reversible and multiple loops leave strangulation grooves separated by intermediate ridges.
The color of the groove is determined by the material and width of the loop, the depth of compression of the skin, translucency and the degree of development of the underlying tissues. From superficial compression, the furrow turns yellow due to the translucence of subcutaneous fat, especially if it is quite well developed; from deep - dark brown due to the transmission of muscles and blood in the vessels.
Details of the loop leave abrasions in the circumference, punctate hemorrhages along the edges of the strangulation groove and in the intermediate ridge, single or multiple breaks, vertical branches, etc.
On the strangulation groove, it is possible to establish specific, group, and sometimes individual signs of the loop.
The specific features of the loop (sliding, motionless, closed, open) are determined by the closed or unclosed strangulation groove and the location of its branches.
Loop group signs are established by the length, width or depth of the furrow, the shape and topography of the bottom, and the presence of intermediate ridges. They can be used to judge the length of the trail-forming part, the width, the shape of the section, and the density of the loop material.
A twisted rope leaves oblique-parallel banded grooves on the neck, separated by ridges, at the tops of which there are punctate hemorrhages.
The hip belt causes striped sagging alternating with patches of intact skin matching the belt buckles.
Twisted soft loops display intermittent narrow elongated strips of intradermal punctate hemorrhages directed longitudinally or obliquely to the longitudinal groove.
Individual signs of a loop are macroscopically established by the presence of sediment along the edges of the furrow. They rarely appear, but it is necessary to try to determine them, always using methods of additional research. Among them, an important place is occupied by the examination of overlays, which makes it possible to establish the identity of the fibers removed from the neck and hands with the fibers of the loop. Individual signs leave knots, buckles and other features of the loop in contact with the neck, displayed by corresponding additional limited sediments along the edges of the furrow.