Forensic Medicine

Forensic Medicine Notes



Thorn is a short spike of plant and can cause scratch, abrasion. It is a linear injury produced by the spike end of thorn running across the skin.

The prick or injury caused by thorn is the ideal site for the anaerobic bacteria (clostridium tetani) which can enter into the human body through wound and can cause medical condition known as Tetanus which is characterized by titanic muscle contractions, hyperreflexia, lock jaw (trismus), glottal spasm, generalized muscle spas, respiratory muscles spasm, seizures and paralysis.

The risk of tetanus after an injury by thorn can be prevented by Anti tetanus serum (A.T.S.)


Knife is commonly used object, it can cause variety of wounds as scratches, incised wounds, tentative cuts and stab perforated wounds.


Different type of knife exists and all have different features. Some common features are

·         Pointed and sharp tip

·         Both end may be sharp

·         A handle

Characteristics of wounds


Shape: tip corn cause linear scratch

Having one sharp end: injury spindle shaped

Size: length is greater than depth and breadth

Angels: mostly clean cut

Margins: incised wounds: straight

Stab wounds: slant

Direction: incised wounds —–> Straight

Stab wounds——————–> slant

Medico legal aspects :

Wounds may be

Suicidal: incised wounds are mostly suicidal with multiple tentative cuts and anywhere on body.

Homicidal: incised and stab wounds are commonly homicidal injuries and are multiple deep and anywhere on body.

Accidental: are less common



Blade is a tool or instrument with cutting action. it can cause incised wound, tentative cuts or self inflicted wounds

Characteristics of wounds
the wound produced by blade have the following characters

·         Wounds are normally straight

·         Cuts cleanly

·         Spindle shaped

·         Having everted and smooth margins

·         Clean  cut angels

·         No bruising over surrounding tissue

·         Profuse bleeding

·         Hair and hair bulb cleaned

Medico legal aspects :

Wounds may be

Suicidal: common and are superficial with tentative cuts .present on approachable parts of body and on opposite side of inflicted hands

Homicidal: also common and mostly deep and multiple and present anywhere on the body.

Accidental: less common and may be multiple and present anywhere on body.


It is the dried juice obtained by the incision of unripe capsule of white poppy. Its main alkaloids are morphine and codeine , used as narcotic and seductive .Apormorphine is used as an emetic. The users of opium can suffer from withdrawal syndrome which is treated with methadone. Other opiates are synthetic congeners of morphine i.e. heroin, pethidine, etraphine etc

Opium poisoning

Majority of cases are consequences of drug abuse .Opiods are most commonly ingested but heroin taken orally or is sniffed like cocaine .heroin has more euphoric effects

Signs and symptoms:

Pulmonary edema: this is commonest cause of sudden death (collapse before completing the injection)

Neurological effects: BP falls, respiratory depression, coma, cerebral edema, patients surviving from coma may suffer delirium, dementia and hypothermia

Infections:  drug abusers share needles, syringes with others so there is high chance of injections like tetanus, hepatitis B, C , HIV etc

Differential diagnosis:

Opium poisoning resembles coma, intracerebral lesions, uremic and diabetic coma, and alcohol poisoning

Fatal dose is 200 mg for non abusers

Fatal period is 9 to 12 hours

Treatment of opium poisoning :

·         Gastric lavage with tepid water than potassium permanganate of  1: 1000 strength

·         Use of enema and purgative

·         Intravenous saline

·         Nalorphine and antiphenazine for respiratory depression

·         Keep the body warm

·         Artificial respiration in case of coma

Postmortem appearance:

External: smell of opium, cyanosed nail and face, distended neck veins, froth at mouth and nose

Internal: stomach shows brownish lump of opium .trachea, lungs, bronchi and brain shows venous congestion .lungs are edematous, blood will be dark.

Medico legal aspect:

It is poison of choice for suicidal purposes .due to its black color, it is not chosen for homicidal use. Homicidal purpose may include inducing abortion. Accidental poisoning is common. Rural Working women use it to make their children sleep while they are on work.


Kerosene oil

It is petroleum distillate used for heating purposes. It’s irritant and dissolve fat

Sign and symptoms of poisoning

Kerosene taste in mouth, a sensation of burning in throat .nausea, vomiting, colicky pain, and diarrhea. the breath, vomitus and urine smell kerosene .slow, shallow respiration, cyanosis, bronchopneumonia, depression of CNS, convulsions, coma and death

Sign and symptoms of chronic poisoning include weakness, pain in limbs, peripheral numbness and parasthesia

Fatal dose id more than 10 ml  and fatal period is few hours


To dissolve kerosene and slow its absorption, give 250 ml of liquid paraffin and saline orally.