INJURY

1. INJURY • Clinically its defined as solution or disruption of the anatomical continuity of any tissues of the body. • Legally under section 44 IPC, its defined as any harm whatever illegally caused to any person in body,mind,reputation or property.

2. Wound • Medico-legally include any lesion,external or internal,caused by violence,with or without breach of continuity of skin.

3. Mechanical Injuries • Are those,which are caused by the physical violence to the body,depending on the manner and how they are caused. • Examples:- Blunt force injury. Sharp force injury. Fire-arm injury.

4. Classification of Mechanical Injuries Blunt Force Injuries/Trauma: Abrasions. Contusions,. Lacerations. Sharp Force Injuries/Trauma: Incised wounds. Stab wounds. Chop wounds. Fractures. Fire arm injuries.

5. Abrasions • Injuries involving superficial layers of the skin and are caused by -Impact of an object. -Fall on rough surface. -Pressure of finger nails,teeth,muzzle of a gun or by rope.

6. Abrasion Tangential Compression (friction/sliding/scrape) (crushing/pressure) Linear Brush Patterned Non-Patterned (scratch) (graze) Impact Contact

7. Age of abrasion • Recent abrasion appears bright red scab 12-24 hrs. • Reddish brown scab 2-4 days. • Healing process starts 4-7 days. • Epithelium grows and dried scab falls 8-10 days. • Absence of infection.

10. Antemortem Abrasions • Reddish brown colour. • Margins are blurred due to vital reactions. Postmortem Abrasions • Yellowish in colour. • Translucent area. • Margins are sharply defined. • Absence of vital reactions.

11. Artifacts in Abrasion • By Ants. • By Insects. • By Animals. • By Marine animals.

12. Medico-Legal Aspects • Site of impact and possibility of internal injury. • Identification of object causing the injury. • Cause of injury. • Direction of injury. • Time of injury.

13. Contusion/Bruise • Contusion is an infiltration or extravasion of blood into the tissue due to rupture of vessels by the application of blunt force. • Examples:-Stick,stone or fist. • Its subcutaneous without discontinuity of skin.

14. Features of contusion • Varies in sizes-Haematoma. • Superficial contusions are slightly raised over the skin. • May not be present at site of the impact. • Superficial contusions appear soon with red colour. • Deeper contusion appear late,can be detected by infra red photography. • Contusions over bony prominences are less visible externally.

15. Factors modifying the appearance of contusion • Site of injury. • Vascularity of the part. • Age. • Sex. • Colour of the skin. • Nature of disease. • Shifting of blood due to gravity.

16. Colour changes in the contusion • Colour changes in the contusion is due to disintegration and haemolysis of red blood cells. • Haemosiderin-Iron pigments,dark brown colour to blue colour. 2-4 days. • Haematoidin-Iron free pigment. Green in colour. 5-7 days. • Bilirubin-Yellow colour.7-10 days. • Normal colour of skin 15-20 days. • Pigments are removed by phagocytes.

20. Age of the contusion • Colour changes. • Histologically. • Healing process depends on: -Size and situation of contusion. -Age and physique of the person. -Presence and absence of disease.

21. Antemortem contusion • Sharp,well defined margins. • Swelling of the tissues. • Discoloration of the skin. • Extravasation of blood into the true skin and subcutaneous tissue. • Doubtful cases-Microscopic examination.

22. Postmortem contusion • Can be produced with in 1-2 hrs after death. • If body is decomposed it is difficult to differentiate between antemortem and postmortem contusions.

23. Self inflicted contusion • Rare-can be inflicted by irritant substances like Marking nut,root of plumbago zeyloxica or rosea. • Can be differentiated by chemical analysis.

24. Homicidal contusion • Shape and size of contusion,indicates the weapon used. Accidental contusion • Their position,arrangement,circumstances and surroundings.

25. Medico-Legal Aspects • Identification of the object. • Degree of violence. • Cause of injury. • Time of injury.

26. Laceration wounds/Injuries • These are the wounds caused by the blunt force resulting torn of the skin and the underlying tissue,with a minimal bleeding.

27. Features of the lacerated wounds • Edges are ragged,irregular and contused. • Margins are abraded due to impact of blunt force. • Deep tissues are crushed. • Hair bulbs are crushed. • Less bleeding due to crushing of underneath vessels. • Presence of foreign materials. • Shape-Irregular. • Size-May or may not correspond to the weapon.

28. Margins-Irregular • Floor-Tags of tissue seen across the floor. • Damage to the tissue-Gross and extensive. • Haemorrhage-Less because of crushing of vessels. • Foreign substances at the site of injury-dust,mud,gravels etc. • Healing-Process delayed due to gross damage and infection. • Scars-Due to damage to skin and tissue.

29. Types of lacerated wounds Split laceration: • Found in pats overlying bones-scalp,face,hands and lower limbs. • Due to perpendicular impact by blunt force. • Due to crushing of skin between two hard objects. • It simulates the incised wound.

30. Stretch laceration: • Due to over stretching of skin and produces flap. • Due to blunt tangential impact-when head strikes on the wind screen of the vehicle. • Due to sudden deformity of bones after fractures.

31. Avulsion wound: • Degloving of skin over the impacted area due to compression and grinding of underlying tissue. • Commonly seen in road traffic accidents and by machinery in heavy industries.

32. Tears laceration: • Due to friction with irregular or pointed end of a weapon or an object on the surface of the body. • Deeper at the string point than at the terminal.

33. Cut laceration: • This type of lacerated wound is produce by “not so sharp” edge of heavy weapon. • Seen in chop wounds. • Margins are not clear cut. • Abrasions or contusions are seen on the margins.

40. Medico-Legal importance • Homicidal-occurs in any part of the body.produced by blows with hard and blunt weapon. • Suicidal-Very rare. • Accidental-Road traffic accidents, accidental fall from height. • Foreign bodies-Mud,gravel,oil etc.

41. Incised wounds • Its produced by sharp cutting instruments-knife,razor,blade,swords,chopper,axe etc. Features: • Edges are regular,clear cut, retracted and averted. • Except in neck and scrotum-edges are inverted. • Spindle shaped wound,maximum widening in the central part. • Length is greater than the breadth. • Breadth is greater than the thickness of the cutting blade.

42. Gaping is greater if underlying muscles are divided across or cut obliquely. • Haemorrhage is excessive due to the cleat division of blood vessels. • Half severed artery bleeds more as they can neither retract nor contract. • Edges of wound may be irregular when skin is loose and if cutting edge is blunt.

43. By nature of the incised wound,weapon used can be identified. • Light sharp cutting weapons-razor blades,knife an produce incised wounds by striking,drawing or by sawing. • Drawing cuts-Deeper at start,gradually become shallow and at the end only skin is cut with scratch “Tailing of the wound”

44. The position of the accused and victim can be identified in homicidal cases,and suicidal cases which hand has been used. • Sawing cuts-Multiple at the beginning and only one deep cut wound called “Tentative or Hesitation cuts” • Bevelling cuts-When weapon is used oblique or tangential way over the body.

46. Heavy sharp cutting weapons-like swords,axes,choppers etc-wounds are greater and severe. Usually homicidal in nature. • Injuries caused by these weapons show signs of bruising over the edges and extensive damage to deeper structures and organs.

47. Incised wounds made by curved weapons like sickle, tangi etc will cause single wound when hit over the convex portion of body. • Weapons applied over the flat surface, it will make two wounds with intact of skin between these two wounds and they will be in the same line.

48. Medico-Legal importance • Homicidal-Any part of the body, commonly on the neck, head and trunk, also be found on the inner side of forearm or hand of victim while defending or protecting. ‘Defence Wounds’. • Suicidal-Found in the accessible parts by light weapons on the throat (cut throat wounds). Tail end of the wound indicates which hand has been used. • Accidental-Any part of the body hands, fingers during the handling of knife, razor blades etc.

49. Weapon • Incised wound means use of sharp cutting weapons. • Bevelled cuts and chop wounds suggest use of heavy or moderately heavy sharp cutting weapons.

50. Manner of use of weapon • Deep chop wounds and bevelling suggests striking by the weapon. • Tailing and hesitation cuts indicate drawing of the weapon. • Multiple superimposed or overlapping injuries are indicated by saw like movement of the weapon.