MLC Injury

Wound

 Surgically: Breach in continuity of skin or mucus membrane.  Legally: Any lesion, external or internal, caused by violence,

with or without breach in continuity of tissue. Injury

Trauma Assault

Battery Hurt Simple hurt Grievous hurt (8 clauses)

 Legally: As per sect.44 IPC, any harm whatever illegally caused

to any person, in respect of body, mind, reputation or property.  Injury which is associated with loss of tissue is called wound. All wounds are injuries but all injuries are not wounds.  An insult either physical or mental affecting one’s state of well being.  Whoever makes any gesture, or any preparation intending or knowing it to be likely that such gesture or preparation will cause any person present to apprehend that he who makes that gesture or preparation is about to use criminal force to that person, is said to commit an assault.  Execution of assault is battery. Wounding will constitute battery which includes even mere touch by a finger. As per sect.319 IPC,  Whoever causes bodily pain, disease or infirmity to any person is said to cause hurt.  Those which do not come under the category of grievous hurt & are simple in nature & heal rapidly without leaving any permanent deformity or disfiguration. As per sect.320 IPC,  1)Emasculation: It means loss of masculine power by -castration -cutting of penis -injury to testis -injury to spinal cord at the level of L2 to L4 vertebra. 2) Permanent privation of sight of either eye. 3) Permanent privation of hearing of either ear. 4)Privation of any member or joint Member: Any organ or limb of subject responsible for performing distinct function.e.g.eyes,ears,nose etc 5) Destruction or permanent impairment of power of any member or joint. 6) Permanent disfigurement of head or face. Disfigurement: Change in configuration or personal appearance 1

Dangerous injury

Injury likely to cause death Injury sufficient to cause death in ordinary course of nature Dangerous weapon

of subject. 7) Fracture or dislocation of bone or tooth. 8) Any hurt which endangers life or which causes sufferer to be in severe bodily pain or unable to follow his ordinary pursuits during the space of 20 days. Ordinary pursuits: means day to day personal activities of individual like attending nature’s call, taking food or bath, wearing clothes etc  Is the one, which possess imminent danger to life by its direct or imminent effects, because of, being extensive in nature, involving important structure of body or organs and also being likely to prove fatal in absence of surgical aid. e.g. injury to internal organs or large blood vessels.  Is the one which constitutes great threat to life on account of its great severity & involvement of important structures of body or because of pre-existing conditions e.g. old age,infancy,diseased state of health. e.g. hypostatic pneumonia.  Is the one, which by virtue of its own direct effects can bring about a fatal result. e.g. injury to brain/spinal cord, injury to heart or large blood vessels, cumulative effects of injury, extensive burns.  Any instrument used for shooting, stabbing or cutting, or any

instrument which, when used as weapon of offence, is likely to cause death, or by means of fire or any heated substance, or by means of any poison or any corrosive substance, or by means of any explosive substance, or by means of any substance which it is deleterious to human body to inhale, to swallow or to receive into the blood, or by means of any animal.

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On the basis of its causation

Medicolegal classification of injuries I] Mechanical injury:  Def.: Damage to any part of body d/t application of mechanical force.  Factors responsible for mechanical injury: a) Force b) Area over which it acts c) Specific effects of the force d) Time taken over which kinetic energy is transferred. 1)Abrasion 2)Contusion 3)Laceration 4)Incised wound 5)Puncture/stab wound 6)Fractures II] Thermal injury III] Chemical injury -d/t corrosive acids/alkalies -d/t irritants like animals, vegetable etc IV] Firearm injury

On the basis of gravity of injury

On the basis of time of infliction On the basis of nature of infliction

I]Simple injury II]Serious injury III]Grievous injury IV]Dangerous injury V]Fatal injury I]Antemortem: recent/old II]Postmortem I]Suicidal II]Accidental III]Homicidal IV]Defence /Protective wounds V]Fabricated /Self- inflicted wounds Def:-These are the wounds produced on the body by oneself (self- inflicted) or with the help of other person (fabricated) & characterized by following i.e. a) usually seen over the accessible parts of the body & are superficial injuries.

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b)history of assault not compatible with the injuries. c) If injuries made by sharp cutting weapon,then injuries not correspond with cuts on wearing apparels. d)Injuries may be detected in different stages of healing. c) motive behind the injuries are - to bring a false charge against enemies - to bring a false charge of sexual offence - to claim more compensation & draw more attention & sympathy -to alter the appearance of injury i.e. from simple to grievous one -to avoid hard duties -to prevent linking the criminal with the crime -to show that the injuries are the result of resisting commission of crime Defence wounds/Protective wounds:  These are the wounds received by the victim in case of assault,by the way of immediate & instinctive reaction of self protection,by raising the arm to prevent the attack or by grasping the weapon.  Usually noticed over palmar aspect of hand,wrist & inner & outer aspect of forearm.  It depends upon: -type of weapon used -degree of force applied  Absent under following circumstances: -when attacked from back -when asleep -under the influence of intoxicating agent -child /elderly persons

Definition

Abrasion  It is a type of mechanical injury characterized by destruction of superficial layers of epithelium or mucus membrane d/t 4

Types

application of mechanical force which may be either friction (sliding) type or pressure (compression) type. Scratch:  It occurs when a body comes in contact with (Linear) object having pointed end. e.g.fingernail,thorn,nail,pin,tip of dagger  The object causing scratch carry torn epithelium in front of it.Thus, the direction of injury is indicated by sharp edge initially & heaped up epithelium at the end. Graze: (Brush/Scraping/ Grinding/Sliding)

 It occurs when wider part of body comes in

Pressure: (Crushing/Friction)

 It occurs when superficial cuticles being

Imprint: (Impact/Compact/ Patterned)

 Type of pressure abrasion where the body is

contact with rough, hard surface either body grazing past or surface grazing past the body. e.g. vehicular traffic accidents  It is also called as brush/friction burn because it is caused by frictional force of rubbing against a surface & resembles a burn after drying.  Here, the direction of injury is indicated by serrated border initially & heaped up epithelium at the end.

destroyed d/t sustained pressure by hard, rough object. e.g. ligature mark in cases of hanging & strangulation.

being pressed by rough, hard object having a definite shape giving the impression of offending object. e.g. forceful impact with a radiator grill or cycle chain etc.

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Atypical: Age of abrasion

 It results d/t application of sustained pressure. e.g. teeth bite marks  Healing occurs by 2 processes: a) Contraction of wound b) Replacement of loss tissue Macroscopically  Fresh: bright red in colour  Within 12-24hrs: Scab/crust forms (Scab: Collection of injured epithelium, dried blood/serum & lymph) which is initially reddish in colour but becomes reddish-brown in 2-3 days.  4-7 days: Epithelium starts growing from periphery to centre.  7-10 days: Scab dried, shrinks, separates & falls off leaving behind depigmented area which becomes normal in colour with passage of time.

MLI

Microscopically  4-6hrs: Cellular infiltration starts.  12 hrs: Appearance of fibrin network with red cells, polymorphs & collagen tissue.  48 hrs: Regeneration of epithelium from periphery.  4-5 days: Abrasion is completely covered with epithelium.  5-7 days: Granulation tissue is formed under the epithelium  7-9 days: Reticular fibres appear.  9-12 days: Collagen fibres are detected.

It gives idea about:  Site of impact & direction of injury (Though these are simple & superficial in nature but sometimes, it may be external sign of serious internal injury).  Identification of object  Time of occurrence of injury  Site of occurrence d/t presence of foreign body over it.  Manner of injury can be ascertained by following: -Abrasion in & around nose & mouth s/o smothering.

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D/Ds

-Cresentric nail scratch abrasion over neck s/o throttling. -Patterned abrasion of ligature mark around neck s/o hanging or strangulation. -Abrasions over face, breast, genitals, inner aspect of thigh s/o sexual assault. -Abrasion over prepuce & glans s/o forceful sexual act or narrow vaginal passage. -Abrasion in & around anus s/o passive agent of sodomy. -Multiple abrasions associated with other mechanical injuries s/o machinery accidents, railway accidents or road traffic accidents. -Abrasion over cornea results into corneal opacity & loss of vision which amounts to grievous hurt. Postmortem abrasion  Usually results d/t rough handling of body i.e. dragging the body after death & are seen over bony prominences.  No e/o colour changes & inflammatory reaction. Abrasions produced by animals (e.g. ant bite/rodents/ cockroaches/aquatic animals)

 These are multiple, small, pale, dry, irregular with nibbed edges.  Usually seen over moist regions of body such as,eyes,nose,mouth,axilla, genitals.

Nappy rash

 Usually seen in infants & results d/t excoriation of skin by excreta.  Its position itself is explanatory.

Pressure sores

 Seen in bed ridden patients & its position itself is explanatory.

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Contusion/Bruise Definition

 Type of mechanical injury characterized by extravasation of blood

in tissue spaces due to rupture of subcutaneous & subepidermal vessels following blunt force impact; without loss of continuity of skin tissue.  Effusion: Collection of fluid blood in body cavities. Haematoma: Localised collection of blood d/t rupture of larger blood vessels. Eccymosis: Small sized bruises of diam.>2mm (pin head) following minute bleeding. Type

Factors affecting bruise

 Intradermal bruise  Subcutaneous bruise  Deep bruise /Come-out bruise: manifest only after few hrs & days.  Ectopic/Percolated/Migratory bruise: Bruise appearing at a site remote from the site of application of force. This is due to the blood which escapes from ruptured vessels usually percolates through line of least resistance.Hence; it is easily influenced by gravity. e.g.1)Black eye/Periorbital bruise/Spectacle haematoma: It is the extravasation of blood in & around the orbital tissue results from: -direct injury to orbital wall -gravitation of blood in cases of injury over frontal region of scalp & fracture of anterior cranial fossa. 2)Bruise behind the ear (Battle’s sign) due to: -injury behind the ear -fall over vertex or fracture of base of skull 3) Blow on outer aspect of thigh produce bruise around knee. 4) Blow on calf muscles produce bruise around ankle joint. Site of wound  Effusion > in lax tissue like periorbital area, face etc. < if dermis is thick like palm, sole. < in well yielding area such as anterior abdominal wall. Age

 Effusion > in females d/t higher amount of fatty tissue. 8

Sex

Vascularity of area Degree of violence Diseases

 Effusion > in children & old subjects as children

has higher amount of subcutaneous fat & in old subjects d/t ↑sed fragility of blood vessels. {Hence females, children & old subjects are called ready –bruiser}.  Effusion α to both.

Complexion of individual Age of bruise

 Effusion > in diseases like haemophilia,scurvy, leukemia  Seen in fair skinned persons as compared to dark ones.

Macroscopically

Microscopically

Colour changes d/t disintegration of RBCs by haemolysis from Hb & break down of Hb into certain pigments by tissue enzymes & histiocytes.

-Infiltration of polymorphonuclear cells (neutrophils) within 1 hr. - Infiltration of lymphocytes by 24hrs. - Infiltration of macrophages by 3 -Initially reddish in days. colour & becomes Afterthat,appearance bluish within a day. of following: -It turns brownish d/t -reticular & elastic haemosiderin (iron fibres. containing) pigment in -fibroblastic next 3 days. proliferation - It turns greenish d/t -neovascularisation haematoidin (iron-free) -fibrinous network & pigment in next 3 days. collagen fibres. 9

Histochemical reaction of enzyme (As per Raekallio’s observation) -↑sed titre of esterase & adenosine triphosphatase by 1hr. -↑sed titre of aminopeptidase by 2hr. -↑sed titre of acid phosphatase by 4hr. -↑sed titre of alkaline phosphatase by 8hr. -also,↑ serotonin & histamine content at the wound margins.

-It turns yellowish d/t bilirubin pigment in next 2 days. -Later on i.e. about 1014 days, yellow colour slowly fades & normal colour of skin restores as these pigments are removed by phagocytosis. {Colour changes are absent in subconjunctival haemorrage d/t diffusion of atmospheric O2 & subdural haematoma d/t absence of mesothelial lining}.

MLAs

It gives idea about:  Site of impact: except Ectopic bruise (Though these are simple but sometimes, it may be external sign of serious internal injury).  Identification of object: pattern bruise caused by whip, cycle chain while parallel bruise caused by cane.  Time of occurrence of injury  Degree of violence applied  Relative position of victim & assailant.e.g.throttling  Manner of injury can be ascertained by following -Contusion in & around nose & mouth s/o smothering -Contusion over neck s/o throttling -Contusion over face,breast,genitals & inner aspect of thigh s/o sexual assault

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Differnceces

 False bruise/Artificial bruise/Simulated bruise: -It is usually produced by juice of vegetable irritants like marking nut, Plumbago rosea (Lal-chitra) & Plumbago zeylanica (Chitra). Locally, -dark brown staining of skin with absence of colour changes. -well defined & regular margins -presence of vesication at periphery containing serous fluid -No e/o extravasation of blood in & around the injured tissue. -Scrapping of the area yields positive chemical reaction Sometimes it is accompanied with stained mark over fingertips & other parts of body d/t scratching by affected fingers.  Congestion:

-It results d/t stagnation of blood inside the capillaries. -Usually it is dusky red in colour with absence of colour changes. -C/s shows washing of blood which comes out of the capillaries.  Postmortem lividity  Postmortem bruise: -Absence of swelling & colour changes -Edges are sharply defined -Absence of inflammatory reaction

Bruises not develop in following conditions:  If body is covered with blanket.  If occurs over thick part of the skin or over yielding body parts.  If pressure is continued till death inspite of application of great force. Subconjunctival haemorrage: Initially bright red in colour, then becomes yellow & finally disappears. It results from rupture of small vessels in subconjunctival tissue d/t  direct injury over orbital wall  fall on vertex  violent acts of coughing(Whooping cough),sneezing, vomiting with 11

straining  violent asphyxial deaths like suffocation, strangulation etc  CO2 & CO poisoning

Laceration Definition

Types

 Type of mechanical injury characterized by tear of skin or deep tissue or both due to application of blunt force.  Three dimensional  Characterized by following: -Edges are irregular, ragged & contused. -Margins are commonly abraded & abraded area corresponds to impacting surface. -Bridging strands of tissue in interior of wound when examined by magnifying lens. -Hair follicles, if present, are crushed. -Blood vessels are crushed resulting into minimal bleeding. -Foreign material usually found in the wound. Split laceration (d/t blunt perpendicular impact) Stretch laceration (d/t tangential impact)

 Here, splitting of skin results d/t compression between weapon & underlying surface. e.g. laceration over head, shin of tibia etc

Avulsed laceration/Grind laceration (d/t horizontal impact)

 Here, separation of skin from underlying tissue d/t shearing or grinding action of weight. e.g. wheel of heavy vehicle

 Here, stretching of skin at breaking point

resulting in laceration at that site. e.g. laceration over fractured bone

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Age

MLCs

Healing by

Cut laceration

 It results d/t cutting action of weapon which is not very sharp. e.g.axe,chopper

Tear laceration (d/t impact against irregular or blunt object)) Internal laceration

 Here, tearing of skin & deep tissue occurs. e.g. motor car door vehicle, blow by broken glass etc

Others

 Patterned laceration e.g. blow by hammer over head

 d/t impact exceeding tensile strength & elasticity of internal organ.

 Postmortem laceration: Usually produced by animals & characterized by -absence of vital reaction. -edges are nibbed or gnawing.  Age estimation is difficult as these injuries are often gets infected & thus delaying the healing process.  Healing occurs by Secondary intention & scar formation is inevitable. It gives idea about:  Site of occurrence of crime ( d/t presence of foreign material)  Identification of object (e.g. cut laceration)  Direction of impact (d/t shelving of margins i.e. one margin overrides the other)  Manner can be ascertained by -Laceration over inner aspect of lip s/o smothering  Primary intention (Primary union): It means healing of wound which has following characteristics -clean & uninfected -surgically incised -without much loss of cells & tissue -edges of wound are approximated by suturing Stages: I] Incised wound as well as sutured track on either side is filled with clot & 13

there is inflammatory response from the margins. II] Spurs of epithelial cells migrate along incised margins on either side as well as around suture track & formation of granulation tissue begins from below. III] Removal of suture at around 7th day results in scar formation at the site of incision & suture track.  Secondary intention (Secondary union): It means healing of wound which has following characteristics -open with large tissue defect & infected -having extensive loss of cells & tissue -wound is not approximated by suturing & left open Stages: I] The open wound filled with blood clot & there is inflammatory response at the junction of viable tissue. II] Spurs of epithelial cells from the margins of the wound migrate at the middle to cover the gap & separate the underlying viable tissue from necrotic tissue at the surface forming scab. III] After contraction of wound, scar smaller then the original wound is left.  Lacerated wound over temporal region of scalp bleed very freely because temporal artery is firmly bound the surrounding tissue, so it is unable to contract even when crushed.

Definition

Incised wound  Type of mechanical injury characterized by clean cut separation of skin or deep tissue or both d/t sharp cutting edge of weapon.

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Characteristic s

 Three dimensional  Characterized by following -Edges of wound are regular, clean cut & everted. -Margins of wound are not contused. {This is usually seen with use of light sharp cutting edge of weapon while with use of heavy sharp cutting edge, edges of wound becomes irregular, ragged & margins become contused.} - Bleeds profusely as blood vessels are cleanly cut & not crushed. (bleeding will be more if artery is nicked or partially cut than completely cut d/t its inability to contract). -Hairs, if present, are cleanly cut & not crushed. -Sometimes, underlying bone may show superficial cuts. -These wounds ‘gapes’ (Gaping means retraction of edges at centre) & appears spindle shaped. Gaping will be more if made perpendicular to ‘Line of cleavage’(Line of langer)i.e. if muscle is cut transversally or obliquely & less if made along ‘Line of cleavage’(Line of langer)i.e. along muscle the direction of muscle fibres. As a result of gaping, the width of wound is greater than the width of weapon. {Lines of langer:These are lines of tension determined by direction of elastic & collagenous fibres in the dermis of skin.} -Initially these wounds are deeper & tails off to superficial wound at its termination. Tailing of wound

 These are superficial cuts involving only

skin seen at terminal part of incised wound results d/t drawing of the cutting edge of the weapon.  Usually caused by light sharp cutting edge of weapon. MLAs:It gives idea about following a) type of weapon used b) relative position of victim & assailant if used homicidally c) if used suicidally, the hand used.

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Hesitation/Tentativ e cuts

 These are multiple, small, superficial,

somewhat parallel, usually skin deep cuts seen near or at the commencement of incised wound & may merge with main incised wound.  Usually caused by light sharp cutting edge of weapon.  Commonly seen in suicidal cut throat & suicidal cuts on wrist & not found in homicidal assaults were defence wounds are present over palmar aspect of hand. MLAs: It gives idea about following a) type of weapon used b) hesitative state of mind at the time of infliction

Bevelled cuts

 These are the cuts caused by obliquely

impact with sharp cutting edge of weapon (heavy), where flapping of one margin of wound at the cost of the other present.  Commonly seen in homicidal assaults. MLAs: It gives idea about following a) type of weapon used b) direction of wound  Accidental bevelled cuts seen over tip of fingers during sharpening of pencil by blade. Chop wounds

 These wounds are caused by heavy cutting edge of weapon but not so sharp.e.g.axe  Commonly seen in homicidal assaults over exposed & easily accessible parts of body.e.g head,face,neck,shoulder & extremities Characterized by following - Edges of wound are irregular, ragged. - Margins of wound are often contused. - Associated with marked destruction of

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underlying tissues. MLAs: It gives idea about following - type of weapon used  Incised wounds over wrinkling areas of the body looks like

Age

MLAs

Causative agent Characteristics

lacerated wounds (inverted edges) & are called lacerated looking incised wound.e.g.scrotum,neck{d/t adherence of platysma & dartos muscle to overlying skin}.  Healing occurs by Primary intention. Fresh: margins tender, covered by soft blood clots & microscopically swelling of vascular epithelium, dilation of capillaries & infiltration of neutrophils. 12-24hrs: Dried scab with blood clots bridging the margins & microscopically ↑sed leucocytic infiltration. 36-48hrs: formation of capillary network. 72hrs: Development of connective tissue, granulation tissue, fibroblast & thickening of capillary walls. 7-10days:Scar formation It gives idea about following - Type of weapon used. - Direction of object. - Time of occurrence. - Site of wound suggest motive/intent/mental status of assailant. Lacerated wound Caused by blunt weapon or fall against hard blunt surface.

Incised wound Caused by sharp cutting weapon.

-Edges of wound are irregular, ragged. - Margins of wound are often contused -Condition of underlying tissues: a) Bleeds less as blood vessels are crushed. b) Hairs, if present, are crushed. c) Foreign material if present indicates the site of occurrence

- Edges of wound are regular, clean cut & everted. -Margins of wound are not contused. - Condition of underlying tissues: a) Bleeds profusely as blood vessels are cleanly cut & not crushed. b) Hairs, if present, are cleanly cut & not crushed. c) Foreign material not present.

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Wearing apparels

of crime. Clothes torn but not clean cut.

Suicidal cut throat  Usually seen over upper part of anterolateral aspect of left side of neck above the level of thyroid cartilage, if person is right handed & vice-versa. Thus, the sloping of wound is towards the floor of mouth  It runs obliquely downwards, forwards, medially across the front of neck, to end over lower part of anterolateral aspect of right side of neck.

Clothes are clean cut.

Homicidal cut throat  Usually seen over both sides of front & lower part of neck below the level of thyroid cartilage. Thus, the sloping of wound is away from the floor of mouth.  The direction of wound will

depend upon the relative position of victim & assailant. i.e. if attacked from right, it runs transversally/obliquely from left to right & vice-versa; if attacked from behind, it resembles suicidal cut throat injury. More than one deep incised wound with absence of hesitant/tentative cuts. Defence wounds are present. Signs of struggle present & sometimes foreign material such as fibre, button, hairs of the assailant may be found in the hand of victim. Usually the weapon is missing at the scene of crime & if found it bears fingerprint impressions of assailant.

 Main incised wound accompanied with hesitant/tentative cuts  Defence wounds are absent  No e/o signs of struggle over body, clothings or place of occurrence.



 The weapon is firmly grasped



in the hand d/t cadaveric spasm or it may be found in the vicinity of the victim & it bears fingerprint impressions of victim himself.  h/o previous suicidal

 Circumstantial & other e/o

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 

attempts, self-inflicted struggle seen at the scene of injuries, suicidal note may be crime. found.  Causes of death in cut throat injury: -Hemorrhagic shock: d/t injury to blood vessels.In suicidal variety,carotid artery usually escapes d/t extension of neck & bleeding is usually venous while in homicidal variety,bleding is usually from the carotid artety as it is completely severed. -Choking: d/t inhalation of effused blood. -Mechanical asphyxia: d/t completely severing of trachea. -Laryngeal oedema: within few hrs of injury. -Vagal inhibition: d/t injury to carotid body. -Air embolism: d/t partially severed external jugular vein & air being sucked in the vein by negative pressure.. -Infection. -Aphonia: d/t injury to vocal cord. Punctured wound(Stab wound) Definition

 Type of mechanical injury characterized by piercing of skin & deeper tissue d/t sharp pointed object. e.g.dagger,ice pick

Characteristic s

 Three dimensional  Depth > length  Types: Punctured wound

 If wound terminates in skin & underlying deeper tissue.

Penetrating wound

 If wound terminates in tissue, organ or cavity. (Here, edges of wound everted d/t withdrawl of weapon).

Perforating wound

 If wound transfix (through & through wound). (Here, wound of entry: larger & edges are inverted while wound of exit: smaller & edges are everted as the weapon usually tapers at the tip; clothes may push inside the wound)

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MLAs

It gives idea about following:  Type of weapon used & its dimensions: a) From the terminal ends of wound: -If both ends are of acute angled: wound appears elliptical shaped & indicates the use of double edged weapon. - If one end is acute & other blunt: wound appears wedge shaped & indicates the use of single edged weapon. - If both ends are of blunt: wound appears circular shaped & indicates the use of pointed circular shaped weapon. -If wound appears cruciate shaped: indicates the use of pointed triangular shaped on cross section weapon. b) From the dimensions of wound: -Depth of wound: usually same as the length of blade of weapon. It may be > if present over yielding parts of body (e.g. anterior abdominal wall) & in PM wounds as compared to AM wounds d/t loss of elasticity & development of RM. -Length of wound: usually same as the breadth of blade of weapon. It may be > d/t -withdrawal of weapon -twisting movement of victim with the weapon -rocking movement of weapon -transversally cutting of muscles -repeated stabbing through the same entry wound It may be < d/t contraction of elastic skin -Breadth of wound: usually same as the thickness of blade of weapon. It may be > d/t gaping of wound -Bruising around wound: indicates the weapon had been inserted up to the hilt.  Relative position of victim & assailant from the direction of wound.  Depth of wound suggests force of impact & intention of assault.  Time of occurrence from the age of injury.

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Causative agent Shape Edges Margins Tract Foreign material Circumstantia l evidence

Punctured wound

Gunshot wound

Pointed object

Firearm (bullet/bunch of pellets)

Wedge/elliptical/circular/cruciat e Clean cut Contused d/t impression of hilt

Usually oval/circular

Convergent d/t tapering tip Part of broken fragment of weapon absent

Irregular, ragged Contused & show e/o blackening,burning,singeing,scorching, tattooing. divergent Part of residues of firearm e.g. unburnt gun powder,wadding,bullet/pellet Present (sound of firearm)

Concealed punctured wound:  These are the punctured wounds made by pin or needle over concealed parts of body such as fontanelle, inner canthus of eye, nostrils, axilla, vagina & rectum.  Usually seen in infanticide cases. Harakiri:  Unusual form of suicide in Japanese where abdomen is punctured by short sword in sitting position resulting in sudden evisceration of abdominal organs. AM clot 1. 2.

PM clot

 Adherent to vessel wall  Firm & laminated in appearance & pulled out in layers. 21

 Not adherent to vessel wall  Soft, brittle, jelly like & pulled out in enmass.

3. 4.

 Composed of fibrin, RBCs, platelets.  Yellowish or grayish white

 Composed of fibrin,RBCs.  Reddish

Fracture Definition Types

 Break in continuity of bone. Direct fracture

1)Focal fracture:  Results from application of small force over small area.  Usually transverse type 2)Crush fracture:  Results from application of large force over large area.  Usually comminuted type 3)Penetrating fracture:  Results from application of large force over small area. e.g. bullet injury.

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Indirect fracture

1)Traction fracture:  Results when a bone is pulled apart by traction. e.g. transverse patellar fracture d/t sudden violent contraction of quadriceps. 2)Angulation fracture:  Results d/t bending of bone. 3)Rotational fracture:  Produces spiral fracture. 4)Vertical compression fracture

Others

1) Traumatic fracture: 2) Pathological fracture: mainly from pre existing disease & little trivial trauma. e.g. osteoporosis,scurvy,osteomalacia,malignancy of bones, vitamin D deficiency or dietary deficiency d/t low Ca intake, prolonged steroid therapy. 3) Simple fracture: fracture showing single break; it may be -very thin (linear) -partial (green stick fracture) usually seen in children d/t more flexible bones than adults. -complete (transecting): transverse, oblique, spiral. Comminuted type: fracture showing multiple Break 4)Closed fracture: if skin remains intact over fracture site. Compound/Open fracture: if skin remains lacerated over fracture site.

Healing of fracture

5 stages of healing:  Hemorrhagic phase  Proliferative phase 23

 Callus phase  Consolidation phase  Remodelling phase Histologically:  Signs of clot formation: within 2 days.  Formation of osteoid matrix within 3 days & its transformation into soft callus within 1 wk. (Soft callus: d/t osteogenic granulation tissue between fractured ends & it becomes visible on X-ray after 3 wks).  The gap between fractured ends is filled with callus within 1 mth. & within 6wks-2mths, it is transformed into bone (hard callus).  Remodelling & reabsorption of excess callus takes about 6mths. At this stage, approximate age can be estimated from: -the extent of remodelling -smoothness of edges -running of trabeculae across the line of fracture MLAs

 Grievous hurt  Site indicates cause of death. e.g. throttling, fracture of long bones causing release of fatty material from bone marrow causing fat embolism & here, diagnosis done by frozen section of tissues stained for fat with Sudan III, Osmic acid. Fracture of tibia & fibula: loss of 500ml-1ltr of blood Fracture of femur: loss of 2 ltr blood.  Time of occurrence from the stage of healing

AM fracture  Shows cellular infiltration at fractured edges accompanied with oedema & infiltration surrounding the adjacent tissue.

PM fracture  Absent

Dislocation differentiate from fracture by following: -lies in the vicinity of joint. -there is restricted mobility instead of abnormal mobility. 24

-absence of crepitus. -if bone felt,they are smooth & rounded,not sharp & angular. Medicolegal aspects of wounds: I) General facts:  Motive  Suicidal note  Place of occurrence  Scene of crime  Clothings  Place where the weapon is found  Nature of weapon  Multiplicity of injuries II) Situation of wound III) Number of wounds IV) Nature & extent of wounds V) Direction of wound VI) Position of the body with relation of injuries VII) Evidence derived from the surroundings  From examination of accused  Trace evidences Medicolegal significance of AM & PM wounds:  Fabrication of false evidence  Avoidance of punishment  Concealment of crime Volitional acts:  The acts which are possible for the deceased after receipt of fatal injury. i.e. running, shouting, climbing up stairs etc. 25

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