Sub topics:
1) Injury/ wound// legal definition/ medical definition
- Any harm caused to a person in body, mind, reputation or properties
- Break in the natural continuity of any tissue in the body
2)Types of blunt force injuries/Mechanism of production
Types
Abrasion
Scratches
Grazes
Pressure abrasion
Impact abrasion
B. Contusions
Intradermal
Subcutaneous
Deep
C. Laceration
Age of Abrasion
bright red scab Recent abrasions ;12-14 hours
Reddish brown scab , 2-3 days
Healing process - 4-7 days
Epithelium growth and dried scab falls , 8-10 days
Absence of infection
3) Blunt for injuries
a) head- common causes: motor vehicle accidents, assaults, sports injuries fall
- causes injuries to scalp, skull, brain, eyes, nose, ears, teeth, lips
b) Trunk
- Abrasion and contusion of chest wall
- rupture of trachea and bronchi
- Injuries to the lungs, heart, large blood vessels
-fracture of ribs
-contusion and laceration of stomach and intestine and kidney
-rupture of liver
-injuries to pancreas
c) Limbs
- Abrasions, contusion or laceration skin, muscles
- Fracture of bones and dislocation of joints
4) General pattern of blunt force external and internal injuries as a result of fall from a height
- depends up on height, orientation of body at point of impact, surface impact and deceleration
Essay
An injury is defined as termination of the natural continuity of any of the tossiues of the livingbody.any physical damage to the body caused by violence or accident or fracture can be called injury. Clinically it is defined as solution or disruption if the anatomical continuity of any tissue of the body. Medico legally , a wound is meant by any lesion , external or internal , caused by violence , with or without breach of continuity of skin. An injury can be fo many types
Mechanical injuries are those that are caused by the physical violence to the body, depending on the manner and how they are caused. It can be of there types
Blunt force injury
Sharp force injury
Fire arm injury
Fracture / Dislocation
Abrasions are the injuries involving the superficial layers if the skin and are caused by any impact of objectbz fall on rough surface , pressure of fingers nails, muzzle of a gun or by a rope. Medico legal aspects include site of impact z possibility of internal injury .the cause , direction and time of injury The identification of object causing the injury needs to focused by a person practicing forensics.Ante mortem abrasions are usually Reddish brown in color and having their margins blurred due to vital reactions.On the other hand , postmortem abrasions are yellowish , translucent having their margins sharply defined because of the absence of vital reactions of cellular action. The age of abrasions is an interest of a forensic doctor.
Contusion is an infiltration or extravasation of blood into the tissue due to rupture of vessels by the application of blunt forces . It is subcutaneous without the discontinuity of the skin. Superficial contusions appear soon with red colour with slightly raised over the skin. It may not be present at the site of impact. Deeper contusions appears late and are defected by infra red photography. Age if the constusin can be analysesd by color changes , histological changes and healing process. Antemortem contusions are sharp well defined margins with discoloration of skin.
Postmortem contusions can be produced after 1-2 hours of death . The identification of object , degree if violence , cause of injury , time of injury are the puzzles regarding contusions.
Lacerations are tears or splits of skin, mucous
membranes, muscle or internal organs produced by application of blunt force to broad area of the body, which crushed or stretched tissues beyond the limits of their elasticity. They are also called tears or ruptures.
Blunt force injury is defined as injury resulting from impact with a blunt object, i.e., one that does not possess any sharp edges. The body absorbs the natural forces like gravity , movement and other stress because of a wonderful characteristics of the soft tissue like flexibility and elasticity . Wound is due to result forces which cross the limits of the elasticity or resistance .
Blunt force injuries
Head
The most common causes of blunt force head injuries are motor vehicles accidents followed by physical assaults, sports and fall from a height. The application of blunt force to the head may results in injury to the contents of skull, either alone or with a fracture of skull. Blunt force may cause permanent damage to the cornea, iris, lens, or vitreous hemorrhage or detachment or rupture of retina and traumatic cataract injuries to the eyes, bleeding from nose, rupture of tympanum and deafness, dislocation of teeth with contusion and laceration of lips and gums, etc. Blunt force injuries may cause intracranial hemorrhage like extradural hemorrhage, subdural hemorrhage and intra-parenchymal hemorrhage which results in clinical presentations like slurred speech, blurred vision, vomiting, loss of consciousness, partial paralysis, etc.
Trunk
Blunt force applied to the chest may cause abrasions and contusions of the chest wall and injuries to the lungs, heart, large blood vessels or esophagus which may or may not be accompanied by external wounds of the chest wall or the fracture of the ribs or sternum. Traumatic rupture of the intrathoracic trachea and bronchi usually occurs due to compressive injury of the chest. If compression is front to back, lateral ribs fractures may occur, and if back to front, ribs tend to fracture near the spine. If the compression is from side to side, the ribs may fracture near spine and sternum. In a fall from a height, or when run over by motor or compression of chest by knee or elbow, the ribs are fractured symmetrically on both sides. Abrasions, contusions and laceration of the abdominal muscles occur due to blunt force. Injury to the stomach is caused by localized blunt force applied to epigastria or left upper quadrant. The more sudden and forceful blow to the abdomen, the more likely is the trauma to be serious and to involve the solid viscera. Mesentery blood vessels may be damaged by crushing force and thrombosis in these vessels may produce infarct in intestine. A kick or a punch in the upper abdomen may injure the pancreas and causes death within few days from inflammation. Liver is most frequently damaged abdominal organ. Most injuries occur on the convex surface. The liver is ruptured by a blow, kick, crushing motor accidents or fall. Similarly, the spleen may be injured by force of compression or traction forces produces laceration and tear respectively. Injuries to the kidney are not frequent as they are situated in relatively well protected part of body. However, contusion and laceration may occur from blunt force applied directly to the posterior or lateral aspect of the kidneys as from blow to the loin.
Limbs
An injury to the limbs, arms, hands, legs and feet is common. Falls are the most common etiology, making up as much as 30% of upper & 60% lower limb injuries. Work related accidents and vehicle crashes are also common causes. Abrasions, contusion and deep lacerated wounds involving the muscles and extending up to the bones are common in traffic and industrial accidents. Deep seated limb injuries affecting the muscles, vessels, nerves or bone may occur without any external evidence of injury. Fracture of the bones and dislocation of joints frequently occurs due to fall from height and other blunt force injuries.
The general pattern of blunt force external and internal injuries in a dead as a result of a fall from a height
Various factors influence the patter of injuring like (1) height (2) orientation of body at the point of impact (3) surface impact (4) deceleration. In case of primary impact with feet (about 60% of cases), the bones of the feet are fractures (comminuted or oblique), pelvic and vertebral column are dislocated and fractured. Liver and spleen laceration can be seen. Aorta is ruptured at junction of aortic arch with the descending thoracic aorta. In primary head impact, open comminuted or depressed skull fractures with brain laceration and partial or complete extrusion of brain may occur. This may also be seen with primary impact of feet and subsequent head impact. Imprint abrasions and contusion are common when the body lands on hard patterned surfaces. Greater the height of fall, more severe is the injuries. The site of primary impact shows most severe injury. When the person falls to the side of the body, fractures of multiple ribs, shoulder girdle, arms and contusions and laceration of back, buttocks or limbs and severe abdominal and thoracic injuries can be seen. The lungs are most sensitive to deceleration; pulmonary hemorrhage and haemothorax are common. The liver is most commonly injured followed by heart and aorta.