WOUNDS WOUNDS Wound is defined medically as disruption

WOUNDS

WOUNDS Wound is defined medically as disruption of the continuity of the tissues produced by external mechanical force).

The term injury often used u synonymously with wound but can have a wider use, including damage to tissues by heat, cold, chemicals, electricity, radiation, in addition to mechanical force (either blunt force or sharp force

• Skin is elastic and more resistant than underlying tissues, blood vessels more resistant to compression than stretching, while hollow or fluidfilled organs sensitive to compression, bone and joints may transmit force to weak points.

• Injury of the tissues occurs when energy applied by the force exceeds the elastic limits of the tissues depending upon (1) physical factors, like degree of force, area over which the force applied, duration and direction of application (2) Biological factors: mobility of the body part and biomechanical properties of tissue (Different tissues have different strengths and weaknesses).

Classification of Wounds • Simple wounds: which are not serious and heal rapidly in less than 20 days leaving no deformity.

Dangerous wounds: • which are serious injuries that may leave a permanent infirmity or take more than 20 days to heal, (but are not fatal).

Permanent infirmity • Loss of a functioning organ or loss of function of this organ. Thus, loss of a nonfunctioning eye-globe is not considered as a permanent infirmity, it is considered as disfigurement.

Fatal or mortal wounds • which cause death either immediately or within a short time after infliction.

Types of wounds Abrasions Lacerations Bruises Incised Wounds

B- MEDICAL CLASSIFICATION OF WOUNDS: • Wounds are classified into abrasions, contusions (bruises), incised (cut), contused (lacerated), stab wounds and firearm wounds.

Abrasions (Scratch, Graze) • Definition: a portion of the body surface from which the skin or mucous membrane has been removed. It is a superficial injury of the skin not involving the full thickness of the skin (epidermis, and papillary dermis or body lining epithelium) they are 2 types: • 1 - Pressure abrasions due to direct impact as finger nail abrasion. • 2 - Friction abrasions due to tangential impact. They are always occur at the site of application of force.

BRUISES (CONTUSIONS, ECCHYMOSES • Definition: Leakage of blood from ruptured small vessels into surrounding tissues due to trauma, resulting in discolouration may be seen in skin, muscle or any internal organ. Site, shape, size, severity of bruising are very variable.

Medicolegal importance of bruises: • (1) Size of a bruise • (2) Site of a bruise:

(3) Classical Patterns and shapes of Bruising 1) Patterned Intradermal bruise 2) Finger pad bruise (3) Tramline bruising 4) Bite marks:

(5) Counter pressure bruises (6) Black eye (peri-orbital haematoma): may occur due to the following causes: 1 - direct trauma to the orbit. 2 -fracture anterior fossa. 3 -- migration from forehead bruise (7) Punching

• (8) Kicking (or shod foot assault • (9) Medical intervention: can produce bruising in the following cases: • 1 - Sternal and cardiac bruising due to cardiac massage. • 2 - Bruising around needle puncture marks.

(4) Age and colour changes of bruises: • Colour of bruises is due to haemolysis of blood by enzymes and cellular products, it begin at the periphery and progress toword centre if large. Smaller bruises may change colour uniformaly. Pigments, including bilirubin and haemosiderin are released from haemoglobin due to degeneration of red blood cells.

• Antemortem Bruise 1. Accompanied by swelling 2. May be of any size. 3. May show colour changes. 4. Blood is clotted in the tissues. • Post-mortem bruise • No swelling. Always small in size. No colour changes. Only slight clotting or none at all

III. CUT (INCISED) WOUNDS These are caused by drawing a sharp bladed instrument along the surface of the skin (e. g. knife, broken glass, razor, etc. . ).

IV- CONTUSED (LACERATED) WOUNDS • Definition: full thickness tearing of the skin (or other tissue) due to stretching, pinning and crushing of tissues by blunt force trauma. • Typically over bony prominences where tissue is pinned and crushed against underlying bone, e. g. scalp, eyebrow, cheek, skin.

V. STAB WOUNDS • These are caused by thrusting (forcing or piercing) a sharp pointed instruments into the body e. g. a knife, sward, or a dagger

Characters of stab wounds • (1) They are more deep than long. • (2) They have regular cleanly-cut edges. • (3) The shape of these wounds may give an idea about the causative instrument. Thus the sharp knife produces a sharp edged wound with one or two acute angles, depending upon wheather the knife is single or double bladed one. The wound is similar in shape to the cross section of the causal instrument.

Defence wound • The victim do it as an immediate and intensive reaction to save himself. They may be of value in differentiating between suicide and homicide. As small cuts in victim’s palm of hand fingers during his attempt to defend himself by gripping the knife. Abrasions and bruises are also examples of defensive wounds denoting resistence. Absence of defence wounds does not rule out homicidal attack, the victim may be incapable of defence for variety of reasons.

Fabricated wounds • These are self-inflected wounds made to accuse an enemy. Wounds may be also fabricated by a murderer to show that he committed the crime while he is in a condition of self-defence or to change the shape and appearance of otherwounds. Fabricated wounds are characterized by being superficial parallel cuts situated in safe areas within the reach of the hand, without corresponding tear or blood stain in clothes.

COMPLICATIONS OF WOUNDS • I. SHOCK, shock is a severe lowering of the effective blood pressure, due to acute failure of cardiac action, disturbance of nervous control of the heart or from severe blood loss.

• (1) Neurogenic shock (primary shock (2) Haemorrhagic shock (secondary shocku

II. EMBOLISM • a) Pulmonary embolism

III. INFECTION OF THE WOUND Due to contamination of the wound with • streptococci or staphylococci. . etc. resulting in diffuse cellulitis and in severe cases septicaemia or pyaemia.

IV. CRUSH SYNDROME • Traumatic acute tubular necrosis which may be ended by renal faliure, mostly complicate limb trauma in which muscle is necrosed liberating myoglobin. Death occurs at about the end of first week after injury.

Disseminated intravascular (coagulation (DIC is a pathological activation of coagulation mechanisms that happens in response to a variety of disease