IDENTIFICATION
- Corpus Delicti (the body of offence): It includes the dead body and evidence to prove death by foul play. Homicidal death occurred at some place as a result of criminal violence. Relatives identify the dead body. Medical officer does the post-mortem examination. Clothing, weapons, etc., have to be preserved as evidence in the trial of the case. Photographs also form part of the exhibits at the trial. They are to be identified, by the person who has taken them.
- Sex Chromatin (Barr Bodies): Sex chromatin can be demonstrated in tissue cells and particularly in cells of buccal mucosa. Hemotoxylin - eosin method can be used. Barr body, a small plano-convex mass present near nuclear membrane in 20 – 80% cells of females. Davidson's body (a drumstick form) is present in 6% neutrophil leukocytes of females and absent in males.
DEATH AND ITS CAUSES
- Somatic Death: Cessation of functions of vital centers in brain stem, permanent stoppage of respiration and circulation.
- Molecular Death: Molecular death is the death of cells and tissues, and occurs after the somatic death.
POSTMORTEM CHANGES
- Suspended Animation: It is a death like state (brain, cardiac and respiratory functions are reduced to minimum). Recovery follows after resuscitation, common in drowning, electrocution, myocardial infarction, newborn infants and administration of anesthetic agents. Artificial respiration and cardiac massage (CPR) causes recovery from a death like state.
LEGAL PROCEDURE
- Conduct Money: Along with the summons in a civil case, certain amount of money is given to a witness towards travelling expenses. The witness can ignore the summons and refuse to give evidence until the amount is paid.
- Compos Mentis: At the time of recording ‘dying declaration’ by the Magistrate, the medical officer has to decide whether the declarant is in possession of sound mind (Compos Mentis). The dying declaration is admissible as evidence, as a person at the point of death tells the truth.
- Leading Question (Which suggests the answer): Leading questions are allowed during the cross-examination of a witness by the counsel for the opposition party to show that his opinions are baseless and unreliable. Even the questions aimed to 2discredit the knowledge, skill and integrity of the witness may be asked.
- Expert Witness: An expert witness is a person of skill in his subject. On account of training and experience he is capable of interpreting facts observed by him. A medical witness (Doctor) is an expert witness, who is capable of drawing opinions and conclusions.
- Hostile Witness: A hostile witness is a person who conceals the truth with some interest or motive and also gives evidence contrary to what he has deposed earlier. This is applicable to both expert and common witness.
- Volunteering a Statement: A common witness is not supposed to volunteer a statement. The medical witness is there to help the court in eliciting the truth. He may volunteer a statement to the court if he thinks that there is danger of miscarriage of justice.
THERMAL DEATHS
- Pugilistic Attitude: (Boxing attitude / Fencing attitude): On exposure to intense heat, the muscles contract due to coagulation of proteins and the body assumes a posture of flexion at the joints. The lower limbs get flexed at hips and knees, and the upper limbs are flexed at the elbows and wrists. It does not indicate antemortem burning, as it occurs in a person who is alive, as well in a dead, due to intense burning.
- Curling's Ulcers: In cases of extensive burns gastro-duodenal erosions are produced due to absorption of toxic products and cause vomiting of blood (hematemesis) usually 3-4 days after burns. The bleeding may be extensive and cause death as a complication of burns.
POSTMORTEM CHANGES
- Marbling: In a decomposed body (in 36 to 48 hours after death) the superficial veins over the upper limbs, shoulders and chest are discoloured as purple-red due to hemolysis of RBCs inside the blood vessels and diffuses into the tissues giving ‘Marbled’ appearance.
- Casper's Dictum: A body decomposes in air twice as quickly as in water and eight times as quickly as in earth.
REGIONAL INJURIES
- Black Eye: Bruising of eye lids due to direct blunt impact on the eye from fisting in physical altercation, injury on the forehead and a fissure fracture in orbital plate of frontal bone in base of skull (anterior cranial fossa) causing peri-orbital hemorrhage.
MEDICAL LAW AND ETHICS
- Penal erasure: State Medical Council maintains a medical register of medical practitioners of that state and has a disciplinary control over them. The name of the doctor is erased or removed from the medical register in a serious professional misconduct. Thus the practitioner is deprived of all the privileges of being a registered medical practitioner.
- Dichotomy: It is fee splitting, i.e. receiving or giving commission to a professional colleague, using agents or touts for procuring patients.
- Covering: Protecting unqualified persons in their activities and assisting in medical field requiring professional skill.
- Res Ipsa loquitur: Means the thing or fact speaks for itself. The patient need not 3prove medical professional negligence as in the absence of negligence the injury would not have occurred in ordinary way. Examples—leaving a swab inside the abdomen during the operation leading to death, tight POP application or splinting to a fractured limb, causing damage or loss of function of the limb or its joint and mismatched blood transfusion causing death.
MECHANICAL INJURIES
- Grazed Abrasion: Results from forcible contact with rough surface, sliding and friction. Epithelium is scraped away in a larger surface area and reveals parallel lines and heaped up epithelium at the end with brush border. It is a common injury in a vehicular road accident.
- Artificial Bruise: It is a fabricated injury by applying irritant plant juices (calotropis/ madar) and of marking nut. Small vesicles are revealed and cause severe itching. These are produced to involve an enemy in the crime.
DEATH AND ITS CAUSES
- Sudden Death: Sudden death is unexpected death occurring in an apparently healthy individual from natural diseases. It may occur in few minutes or few hours. Trauma and poisoning do not play any part in its causation.
MEDICOLEGAL AUTOPSY
- Exhumation: Exhumation is digging out of the dead body from its grave. This is done in suspicious death when foul play is suspected. Exhumation is done in suspected poisoning death and also to establish the identity. Executive magistrate is empowered to order for Exhumation. The presence of relatives, medical officer and the police officer is also necessary at the gravesite. Identity of the specific grave/ burial place is necessary before starting the digging.
FORENSIC PSYCHIATRY
- Hallucinations: It is a false sense perception without any external object stimulus to produce it.
They are of various types:
- Auditory: A person hears imaginary voices.
- Visual: A person sees non-existing shapes of animals.
- Olfactory: A person smells of non-existing odors.
- Gustatory: A person has a taste in his mouth, without any food to cause it.
- Tactile: A person has imaginary sensation of insect crawling over the skin.
- Lilliputian: Perception of objects to be much smaller than they are.
- Illusion: It is a false interpretation by senses of an object or stimulus of real existence e.g. a dog is mistaken for a panther, a tree imagined for a ghost in dark.
- Obsession: An idea constantly entertained by the individual and persists inspite of all his efforts to drive it from his mind, e.g. a wife believing her husband to be unfaithful, a person spending his entire night by bolting and unbolting without going to bed.
- Idiot or Idiocy: They suffer from defective mind from birth. Their mentality is that of three years child. I.Q. is 0 to 20. They reveal microcephaly and mongolism and malformation of head, face and brain.
- Imbecile and Imbecility: They suffer from defective mind from birth. They cannot manage themselves and taught. Their mentality is that of a child of 7 years. IQ is 20 to 50.
- Feeble Mindedness (Moron): They suffer from mental defectiveness and require care and protection. Their mental age is of 11 years and IQ is 50 to 75.
BLOOD STAINS
- Hemin Crystal Test (Teichmann's test): It is a micro chemical examination test for identification of a blood stain. A crystal of sodium chloride and 2 to 3 drops of glacial acetic acid are placed on piece of cloth suspected of bloodstain on a glass slide. A cover slip is applied. The acid is evaporated by gently heating over flame. The slide is examined under microscope after cooling. Yellowish-red to brownish black rhombic crystals of hemin (hemin chloride) are seen if blood is present.
- Hemochromogen Crystal Test (Takayama's test): A piece of cloth from suspected stain of blood is placed on a glass slide and 2 to 3 drops of Takayama's reagent (sodium hydroxide, pyridine and glucose) and it is covered with a cover slip. Pink feathery crystals of hemochromogen in clusters or sheaves are formed within 5 minutes, (Slight warming of the slide may be required). It is a reliable test even with old stains.
SEXUAL OFFENCES
- Seminal Stains Identification: Detection of seminal stains are useful in investig-ation of sex crimes. Choline iodide crystals test and spermine picrate crystals test are useful.
- Choline Iodide Crystals Test (Florence test): A drop of extracted stain by using 10% hydrochloric acid is dried on a glass slide. A cover slip is placed over it. Then a drop of florence solution (potassium iodide, iodine and water) is allowed to run under the cover slip. If semen is present, choline of semen reacts with florence solution and forms rhombic brown crystals of choline iodide. Negative reaction is more important proof to say that the stain is not of semen.
- Spermine Picrate Crystals Test (Barberio's Test): A saturated solution of picric acid (aqueous or alcoholic) when added to seminal stain fluid extract produces needle-shaped yellow crystals of spermine picrate (spermine is prostatic gland secretion present in semen).
- Eruption of Teeth and Age Estimation
- Eruption of temporary teeth1. Central Incisor(Lower and Upper)-about 6 months2. Lateral Incisor(Lower and Upper)-about 7 months3. Canine-about 1 ½ year4. First Molar-about 1st year5. Second Molar-about 2nd year
- Eruption of permanent teeth1. First Molar-about 6 year2. Central Incisor-about 7 year3. Lateral Incisor-about 8 year4. First Bicuspids-about 9 year5. Second Bicuspids-about 10 year6. Canines-about 11 year7. Second Molar-about 12 year8. Third Molar(Wisdom teeth)-about 17 to 25 years
- Medicolegal Autopsy Incisions
- Scalp incision on head: To extend the neck, a wooden block is placed under the shoulders and the head is fixed by headrest, (with a groove in a wooden block, which holds the back of the neck). A coronal incision is made in the scalp, which extends from the one mastoid process to the other behind the ear passing across the scalp over vertex after parting the hair. The scalp is reflected anteriorly upto the level of supraorbital ridges and posteriorly little below the external occipital protuberance. In the third step temporal and masseter muscles are cut on either side of skull for the saw cut. The saw cut in the skull is made horizontal on center of forehead extending to the bases of mastoid processes on both sides then upwards to point little above the external occipital protuberance for removing the calvarium. A chisel and hammer is carefully used to avoid false fractures. The skullcap is pulled backwards and is removed. For removing the brain from the cranial cavity, the dura mater is cut along the superior sagittal sinus with scissors or scalpel. Dura mater is divided from before backwards at the level of skull by sawing on both sides. In the next step anterior end of falx cerebri is divided and pulled backwards using a forceps. Inserting fingers below to lift frontal lobes of the brain. Optic nerve, cranial nerves and blood vessels are identified and cut. Tentorium cerebelli is cut on either side. To cut the spinal cord below the medulla oblongata in the foramen magnum, the tip of knife is passed and it is incised. Brain is removed by using both hands carefully. Dura mater is removed from the base of skull to examine for any fractures in cranial fossa (weight of the brain is to be taken before its sectioning).
- Thoraco-abdominal incisions: Skin incisions-neck and thoraco-abdominal (I and Y incisions):
- “I” shaped incision: It extends from chin and vertically down to the symphysis pubis, taking one side, left or right of the umbilicus. It is a routine type of incision followed in autopsy.
- “Y” shaped incision: From acromial processes the incision extends below the breast up to the xyphoid process with another incision down 6wards in mid-line to the symphysis pubis. This is followed in European countries so that a tie can be applied to the dead body and also to avoid ugly appearance of suturing in the neck.
- Another midline incision also can be taken extending from suprasternal notch to the symphysis pubis. This type of incision also is better for routine autopsies.
HEART
Isolation of Heart and its Dissection: During postmortem examination the heart is removed from the chest cavity by cutting away its large blood vessels close to its base. Before isolation, the pulmonary arteries are examined for any embolus by incising it. In pulmonary embolism, the embolus can be found extending from the right ventricle into the pulmonary conus, pulmonary trunk and its pulmonary arteries (left and right divisions). Heart is examined in situ for pulmonary embolism, as the embolus gets dislodged on its isolation and to establish the cause of death due to pulmonary embolism becomes more difficult and impossible.
The heart is opened in the direction of blood flow using an enterotome.
Right atrium is cut, open by passing one of the blades into the inferior vena cava and through the right atrium then into the superior vena cava. A cut is made into the wall of right auricle to see any thrombi inside the auricle. In second step, right ventricle is cut open along its lateral margin cutting through the tricuspid opening between the two cusps after measuring the circumference of the tricuspid opening by a graduated cone having markings. Enterotome is turned to cut the anterior wall of the right ventricle close to the apex and then close along the inter ventricular septum into the pulmonary opening and cutting through between the two cusps into the pulmonary trunk and the pulmonary arteries. In another step, the left atrium is cut between the pulmonary veins openings. Then left atrium is cut along its left border into the mitral orifice between the two cusps and then along left border of the left ventricle upto the apex and then turned close to interventricular septum and extended into the aortic orifice between two cusps into the ascending aorta. Weight of the heart is taken after removing the blood clots from its chambers. The thickness of the right and left ventricles is also measured. For examining the coronary arteries serial sections of 2-3 mm thickness are made across the anterior descending branch of left coronary artery starting from the apex towards the base of the heart. Atherosclerosis and coronary thrombosis is found in first 1 cm after the division, causing myocardial infarction in the apex, anterior part of interventricular septum and the left ventricular wall as the myocardium is supplied by the anterior descending branch. The circumflex branch and the right coronary artery is also cut across in serial sections of 2-3 mm thickness away from their origin. Commonly coronary thrombosis and atherosclerosis blocking the lumen completely 7is found in first 1 cm, soon after its origin from the left coronary artery. Myocardial infarction is found in posterior wall of the right ventricle and the posterior part of inter ventricular septum in thrombosis of right coronary artery. In another step, starting from the apex, interventricular septum is cut through along its length upto the base of heart and then examined.
The isolated heart can be incised and examined in a different way also. Horizontal sections of 2-3 mm in thickness can be cut across, starting from the apex to the base of heart which reveals the pathological condition of myocardium, coronaries, chambers of the heart, papillary muscles and the valve cups, etc. After dissection of the heart, it is placed in 10% formalin for fixation and further microscopic examination of the myocardium and of the coronaries.
THERMAL DEATHS
- Lightning: Lightning occurs from electrical discharge of direct current more than 1000 million volts from the cloud to the earth.
Postmortem examination reveals:
- Burning and tearing of clothes.
- Burns with contusions, lacerations, rupture of internal organs and fractures of bones.
- ‘Arborescent markings’ or ‘Filigree burns’ extending from the shoulders downwards-resembling fern-like pattern of branches of a tree.
- Metallic objects, jewellery and keys, etc., on the person become hot and give rise to burns on skin.
- Bunch of keys and other iron objects on the person reveals magnetization.
- Metallic objects show, melting effect in lightening.
IDENTIFICATION
- Sex of Skull: Female Skull - General features
- Small and smooth.
- Forehead: Nearly vertical and rounded
- Supra-orbital ridges; not raised and not prominent.
- Glabella not prominent.
- Orbits rounded.
- Frontal eminences and parietal eminences are large and prominent.
- Mastoid process: Small and smooth.
- Digastric groove: Shallow and less marked.
- External occipital protuberance: Not prominent.
- Occipital condyles: Small.
- Superior and inferior nuchal lines: Not raised and not prominent.
- Palate: Parabolic.
Male Skull: General features:- Large, heavy and rough due to raised muscular ridges.
- Fore head is steep / sloppy.
- Supra-orbital ridges; raised and prominent.
- Orbits: Square shaped.
- Glabella: Prominent.
- Frontal and parietal eminences: Not prominent
- Mastoid processes: Large and rough.
- Digastric groove: Deep.
- External occipital protuberance: Raised and prominent.
- Superior and inferior nuchal lines: Raised and prominent.
- Palate: U-shaped and broad.
- Occipital condyles: Large.
SEXUAL OFFENCES
- Masochism: It is opposite to sadism. More common in women. Sexual gratification is obtained by suffering pain. They get pleasure from being beaten, humiliated, torture, by their sexual partner. Severe bodily injury or murder may take place by their husbands and lovers.
- Necrophilia: Sexual intercourse with a dead body.
FORENSIC PSYCHIATRY
- Delusion: It is a false belief in something which is not a fact.
Various types of delusions:
- Delusions of grandeur: A person imagines himself rich when he is actually poor.
- Delusions of persecution: A person imagines that other people are going to harm him.
- Delusions of reference: A person imagines that people are referring to him.
- Delusions of influence: A person imagines that his thoughts and actions are controlled by external agency.
- Delusions of infidelity: A person imagines that his wife or husband is unfaithful.
- Delusions of self-reproach: Self accusation
INFANTICIDE
- Ossification centers in a newborn full term child: (A case of Infanticide) Development of ossification centers (intrauterine life) has to be examined in: Sternum (breast bone), lower end of femur and upper end of tibia (at knee joint), calcaneum, talus and cuboid (at ankle joint).
- Sternum (breast bone):
- Manubrium sterni ossification center: one or two centers are developed in 5th month intra-uterine life.
- Body of sternum: In first segment – 5th month (intra-uterine life).
- Second segment – 6th month (intra-uterine life).
- Third segment – 7th month (paired ossification centers).
- Fourth segment – 10th month (intra-uterine life).
- Before birth all the ossification centers are developed in the body segments of sternum (Ossification center in xyphoid process develops at the age of 3 years after birth).
- Lower end of femur and upper end of tibia: Ossification center in lower end of femur and upper end of tibia are examined by flexing the knee and making a horizontal incision in the skin of knee over the patella. Tissues around the lower end of femur and upper end of tibia are dissected to expose them. They are cartilaginous ends. Lower cartilaginous end of femur is sliced across using a sharp knife in to number of slices. They are examined for the presence or absence of ossification center in the middle. When present, it is seen as a dark-red or brownish spot, developed 5 mm in diameter in a full term newly born infant.
- Calcaneum, talus and cuboid (tarsal bones of ankle and foot): Ossification centers can be examined by making a deep cut through the sole of foot using a sharp knife. Incision should follow the line 9joining two points: One point in the inter space of 3rd, 4th toe and another point at the middle of heel. The deep cut is made passing through the calcaneum, talus and cuboid, which are cartilaginous. Cartilaginous talus is seen above the calcaneum and the cuboid anterior to the calcaneum.
Ossification center appear in
- Calcaneum: At the end of fifth month of intra-uterine life.
- Talus: At the end of seventh month of intra-uterine life, and in
- Cuboiod: At the end of full term intrauterine life.
Medicolegal importance: Ossification center when developed in the talus, it indicates, the infant is viable. Only in the calcaneum it indicates prematurity and is non-viable. When ossification center is developed in cuboid also it indicates full term and viable child that has been put to death.
ABORTION
- Complications of Criminal Abortion
Immediate Complications
- Reflex cardiac inhibition in attempting to dilate the cervix and cervical canal (without any anesthesia) results in sudden death.
- Air embolism and sudden death due to air emboli sucked in to placental sinusoids due to partial separation of placenta and negative suction of air into them, which is carried in to systemic circulation from the right side of heart and causing air embolism in cerebral or coronary arteries.
- Hemorrhage and shock due to injury to the placental site and partial separation of placenta, causing hemorrhage from its open sinusoids due to insertion of instruments or abortion stick. Perforation of vagina, cervix, posterior or lateral fornix and uterus results in internal bleeding in to the Douglas’ pouch. Loops of small intestine are perforated.
- Fat embolism due to introduction of soapy solution and amniotic fluid embolism due to perforation of amniotic sac.
Delayed Complications
Infection and sepsis, causing endometritis, parametritis, peritonitis, septicemia, due to introduction of abortion stick. E. coli, clostridium welchii, cl. tetani and other anerobic organisms like anaerobic strep-tococci causing gas gangrene and purulent discharge.
VIRGINITY
- Different Types of Hymen:
- Annular or oval: With central opening.
- Crescentic or semi lunar: Opening to one side.
- Vertical: With vertical opening.
- Cribriform: With several openings.
- Imperforate: With no opening.
- Infantile: With a small opening in the middle.
- Septate: With two lateral openings and a septum in the middle.
- Fimbriated: Has undulated margin with several notches which do not extend up to the vaginal wall.
- Infundibular: Funnel shaped.
- Ruptured hymen: Ruptures on healing extend up to the vaginal wall.
- Carunculated: With only remnant tags of hymen present.
- Caruculae hymenalis of carunculae myrtiformes: Ruptured hymen with thin projections of mucous membrane situated at the vaginal orifice.
They are of different types as mentioned above. Annular, crescentic hymen is common. In a virgin, hymen is intact and is ruptured during sexual intercourse. The hymen may be congenitally absent. At puberty a finger can be easily passed through the hymenal opening. It may be elastic and fleshy.
- Common Causes of Rupture of Hymen:
- Sexual intercourse.
- Trauma: Accidental fall on projecting object.
- Masturbation: insertion of foreign body and digital masturbation.
- Unhygienic habits of individual / lack of cleanliness.
- Local infection from threadworm.
BURNS AND SCALDS
- Scalds: Scalds are produced by ‘moist heat’ from boiling water, boiling oil or ghee. Children usually fall accidentally in boiling liquids ‘sambar’, hot tea, etc. steam, splashing from boiling water causes scalds. It causes redness and blister formations. There is no burning, singeing of hair, blackening of skin or charring of tissues.
Medicolegal Importance
- Mostly accidental—children are victims commonly.
- Intentional scalds to punish a child. His mother makes him to stand or sit in a bucket of hot water.
- Rule of nines in burnsRule of nine is used for estimating the percentage of surface area of burns on the body.i.Head and neck:9%ii.Right upper limb:9%iii.Left upper limb:9%iv.Right lower limb:18%v.Left lower limb:18%vi.Anterior aspect of trunk:18%vii.Posterior aspect of trunk:18%viii.Genitalia:1%
Percentage of Burns in Infants and Children
Area | Age | |||
|---|---|---|---|---|
0 yr. | 1 yr. | 5 yrs | ||
I. | Half of head | 9½ | 8½ | 6½ |
II. | Half of one thigh | 2¾ | 3¼ | 4 |
III. | Half of one leg | 2½ | 2½ | 2¾ |
INFANTICIDE
- Criminal Causes of Infanticide:Acts of Omission: (Neglect)
- Failure to protect the child from heat and cold soon after delivery.
- Failure to provide assistance during labor.
- Failure to clear mouth and air passages of mucus and maternal discharges (placental blood, amniotic fluid and mothers urine).
- Failure to tie the cut end of the umbilical cord properly.
- Failure to feed the child of milk.
Acts of Commission: (deliberate acts to cause death)- Smothering: Blocking the nostrils and air passages by a pillow or soft cloth.
- Strangulation:
- Ligature strangulation.
- Manual strangulation or Throttling.
- Head injury: By striking the head of the infant against a wall or crushing under the feet of charpai.
- Burning.
- Drowning.
- Puncture wounds: Concealed in certain parts e.g. in axilla, inner canthus of eyes, vagina, rectum, fontanellae-using a needle.
- Poisoning: Applying opium to the nipple of the mother and feeding the baby.
- Rule of Hasse: Approximate length of an embryo measured in centimeters from crown to heel of foot (i.e. crown to heel length) during the first five months of pregnancy can be obtained by squaring the number of months of pregnancy and in second half of pregnancy the number of months multiplied by 5.
First five months of pregnancy (intra-uterine life): Months of pregnancyLength in centimeters1 × 11 cm2 × 24 cm3 × 39 cm4 × 416 cm5 × 525 cmSecond five months of pregnancy (intra-uterine life): Months of pregnancyLength in centimeters6 × 530 cm7 × 535 cm8 × 540 cm9 × 545 cm10 × 550 cmSitting height of the fetus is about- 12 cm at fourth month
- 25 cm at seventh month
- 36 cm at tenth month (full term)
Development of fetus and age of an infant in lunar months:- First month: Length 1 cm.
- Second month: Length 4cm. Hands and feet are webbed.
- Third month: Length 9 cm. Eyes are seen as closed. Fingers and toe nails develop
- Fourth month: Length 16 cm. Sex is in developing stage. Lanugo hair are seen
- Fifth month: Length 25 cm. Weight about 400 gm. Finger and toe nails developed. Scalp hair appears. Vernix caseosa is seen on skin.
- Sixth month: Length 30 cm. Weight 700 gm. Eyebrows and eyelashes are formed. Subcutaneous fat appears. Testes are near the kidneys, pupillary membrane present. Eyelids are adherent. Ossification centers developed in calcaneum and manubrium sterni.
- Seventh month: Length 35 cm. Weight 1.2 kg. Pupillary membrane absent and eyelids are open. Skin is red. Testes at the level of external inguinal rings.
- Eighth month: Length 40 cm. Weight 2 kg. Finger nails at the level of tips of fingers. Scalp hair thick. Skin is smooth. Left testis is descended into scrotum. Placenta weighs about 500 gm. Ossification center in talus is developed.
- Ninth month: Length is 45 cm. Weight is 3 kg. Scalp hair dark and 4 cm in length. Meconium present in large intestine. Scrotum contains both testes. Ossification center is developing in the lower end of femur and its diameter is less than 5mm.
- Tenth month: Length is 50 cm (crown to rump length 30 cm). Weight is 3 to 4 kg. Head circumference is 35 cm. Scalp hair is dark 5 cm. long. Lanugo hair present only on shoulders. Skin is covered with vernix caseosa. Fingernails project beyond the fingertips (toenails project beyond their toe tips). Ear and nose cartilages are formed. Both testes are present in the scrotum. Labia majora covers labia minora and clitoris. Umbilicus is situated midway between Xyphoid process and symphysis pubis. Ossification center is fully developed in the lower end of femur (5 mm in diameter), upper end of tibia, 12talus and cuboid. Ossification centers are present in manubrium sterni and in all segments of sternum. Anterior fontanelle is not closed.
MECHANICAL INJURIES
- Contusions
- Bleeding occurs into the tissues from ruptured capillaries.
- During healing, color changes from red to bluish-red; green to brown and yellow in the end takes place in a contusion, resulting from disintegration of RBCs and breaking down of hemoglobin into hemosiderin, hemotoidin and bilirubin by the action of enzymes.
- Postmortem Destruction by Animals
- Lack of blood in the area where postmortem nibbling and chewing is caused by rats and other animals.
- Postmortem injuries are usually brownish-red and lack in blood.
- Lacerated Wounds
- Tissues are seen bridging from one side of the wound to the other side.
- In a lacerated wound showing ‘undermining’ the direction of force acting on the head can be determined, as the site of wound which can be lifted off, the bone is the undermined side. (Left side when undermined indicates that the blow came from the right side.)
- Avulsion Lacerations: In avulsion laceration, grinding action and tangential force acts causing separation of skin from the underlying tissues over a large area. The underlying tissues and muscles are crushed and bones are fractured. Skin separation occurs due to wheel of a vehicle rotating. The skin reveals externally abrasions and beneath a pocket filled with blood and liquid fat.
- Incised Wounds: A knife, razor, dagger, a glass piece can cause incised wounds. It has clean cut edges, the length of the wound does not correspond to the length of blade, and depth is also variable. The end is marked by tailing off. The width in the center is due to retraction and gaping of edges and causes spindle shape. In a light cutting weapon no bruising of margins occurs and where as in a heavy cutting weapon margins are irregular and bruised.
- Lacerated Wound on Scalp Head
- Hair bulbs are crushed, bridging of tissues across the edges and edges are bruised and abraded.
- An object with a blunt rounded end produces a stellate lacerated injury.
- A metal rod produces a ‘’Y’ shaped injury.
- Lacerated wound of scalp looks like an incised wound.
- On examination with a hand lens its margins look irregular.
- When caused by a blunt heavy cutting weapon (axe) lacerated wound is caused than an incised wound.
- Homicidal Cut-throat Wounds: They are deep and deliberate without tentative cuts, directed horizontal, situated in lower part of neck, carotid arteries are injured, and cervical vertebra may be injured.
- Cut Lacerations: These are produced by heavy cutting weapons. The skin is crushed and splits in its central part. Edges are rough and irregular, skin margins are abraded and contused from the flattened surface of the weapon. Deeper tissues are found divided unevenly and tissue tags bridging across the margin in the depth of the wound. Blood vessels nerves and connective tissue fibers are seen stretching across, along with the crushed hair bulbs and reveal echymosis indicating its antemortem nature.
- Cycle Chain: Causes pressure abrasion (patterned abrasion)—imprint of cycle chain is produced.
IDENTIFICATION
- DNA Profile
- All individuals (except identical twins) have different DNA sequence on their chromosomes (the blood, semen, teeth pulp, and tissues of the body may be used).
- Identification of abandoned infants in dust bins and isolated places is possible to establish by DNA testing.
- Battle's Sign: It is revealed by bluish discolouration of skin behind the ear due to accumulation of blood underneath the scalp due to fracture of base of skull in posterior cranial fossa.
ABORTION
- Amniotic Fluid Embolism: It occurs in criminal abortions. Amniotic fluid enters into maternal venous circulation causing immediate death in most of the cases. Presence of mucin, fetal squamous cells, lanugo hair, vernix caseosa and fat globules are found in lung capillaries on microscopic examination.
TOXICOLOGY
- Elimination of Poisons from the Body:
- By promoting renal excretion: Using normal saline or 5% Glucose IV slow drip.
- Use of purgative: Magnesium sulphate removes unabsorbed poison from intestinal tract.
- Peritoneal dialysis.
- Hemodialysis.
- Symptomatic treatment.
- Chelating Agents: They are used in metallic compound poisoning to form soluble complexes and excreted in urine.
- B.A.L: (British anti lewisite, dimercaprol) used in arsenic, copper and other metallic compounds poisoning.
- EDTA: Used in lead, copper poisoning.
- Penicillamine: Used in heavy metallic compounds poisoning. It can be given in normal saline drip (slow) for 2-3 days.
MECHANICAL INJURIES
- Battered Wife: Physical and mental injuries are inflicted to a wife by her husband. They suffer from physical injuries giving pain and suffering which are visible and can be easily detected on examination. Mental trauma is evident from personality change in the woman who becomes neurotic and presents psychiatric problems.
PREGNANCY AND DELIVERY
- Lochia: It is discharged from the uterus after delivery and lasts for 2-3 weeks. In first week it is bright red in color hence, called “Lochia rubra”, and during next week (four to five days) it is pale hence, termed “lochia serosa”. After a week it becomes yellowish-gray, hence termed as “Lochia alba”.
ABORTION
- Instrumental Interference and AbortionEvidence at the scene:
- Disarranged under clothing of the woman, smell of dettol may be present, when it is used.
- Evidence of instrumental interference in the form of rupture of membranes and draining of the liquor amnii, evidence of dilators use and volcellum marks on the anterior lip of cervix uteri.
- Evidence of blood soaked cotton wool and linen.
- Use of abortifacient paste introduced locally as well as the presence of paste flakes at the scene.
- The presence of instruments, etc. used in inducing abortion at the scene.
IMPOTENCY AND STERILITY
- Artiificial Insemination
- The donor and his wife must give consent.
- The identity of the donor should be kept in secret.
- The donor should not know to whom the semen is introduced.
- The donor should not know the result of insemination.
- The donor should physically and mentally free from hereditary disease and genetic defects.
- The donor should not be a relative of wife or the husband. Age should be less than 40 years.
- The donor should have his own healthy children.
- The race, facial features, color of skin and characteristics of the donor should resemble those of the husband or of the wife.
- A witness must be present when artificial insemination is done.
- ‘Pooled semen’ (i.e. husband semen mixed with donor's semen) is to be preferred.
- The physician who administered artificial insemination should avoid delivery of the child.
PREGNANCY AND DELIVERY
- Pregnancy and Delivery: 210 days is the age of viability, i.e. the children born alive after 210 days can survive. Children born after 180 days of intrauterine life are capable to survive and lead an independent life when separated from their mother.15
- Posthumous Child: A child born after the death of his father (the mother being conceived by the said father).
- Superfecundation: Fertilization of two ova discharged from the ovary at the same period by two separate acts of coitus committed at short intervals - resulting in twin pregnancy. Spermatozoa fertilizing the ovum may be from a different man (One may be white and other black person).
- Superfetation: Fertilization of a second ovum in a woman who is already pregnant. When two fetuses are born, they show different stages of development.
- Legitimacy and Paternity:
- Supposititious children: These are fictitious children. A woman pretends pregnancy and delivery, and produces a living child as her own for claiming property.
- Atavism: Children do not resemble their parents but resemble their grand parents.
- Test Tube Babies: Ovum is removed from the ovary through the abdominal wall incision and fertilized outside by the sperm of her own husband in an artificial medium. At the stage of development as blastocyst, the embryo is removed and returned to the uterus through the uterine cervix for implantation in endometrium. Similar implantation of one of her ova fertilized externally by donor sperm is also done.
- Surrogate Mother: (A hired woman): An ovum from the wife is fertilized ‘in vitro’ with the husband's semen and this embryo is implanted in the womb of hired woman. After delivery the baby is returned to the biological father and his wife.
DEATH AND CAUSES
- Suicidal Pact: Suicide pact in dead bodies may be revealed in the form of grabbing hands together in dead bodies.
IDENTIFICATION
- Tattoo Marks: Tattoo marks are seen in front of elbow to conceal needle marks, over hands and lips in drug addicts. A tattoo on web between thumb and index finger may be found in homosexuals. In faded tattoo marks pigment is found in regional lymph glands in a dead body. A faded tattoo mark can be revealed by UV lamp and infrared photography can be done.
VIRGINITY
- True Virgin and False Virgin: True virgin has an intact hymen, fourchette and posterior commissure. Vagina is narrow with rugae in its wall.False virgin shows ruptured hymen, vaginal orifice is not covered by labia majora, fourchette is not intact and rugae are less prominent.
MECHANICAL ASPHYXIA
- Partial Hanging: Partial hanging occurs due to kneeling or in sitting position commonly. Point of suspension is mostly from a branch of a tree, a door knob, a nail in the wall, sofa or chair, stair case, or from railing fence and some part of the body or feet is resting on the ground or on some platform.16
- Diatoms: Diatoms are microscopic algae having silicacious coating. They are found in shallow waters. They are of many shapes. Mostly their size range from (average 10.80 microns). In case of death due to drowning the diatoms from the drowning medium get into systemic blood and get deposited into various internal organs and the bone marrow. Their recovery from bone marrow is diagnostic of death from drowning. Water from the site of drowning is also collected in a glass bottle. The bone marrow from the sternum is collected and placed in Kjeldahl flask. Nitric acid is added for chemical digestion and the flask is kept overnight. Next morning the transparent yellow fluid is centrifuged. The deposit is poured on to the slide and covered with a cover slip. Examined under the microscope when the fluid film is still wet under the cover slip, the diatoms can be demonstrated. Similarly the water sample also is examined (Diatoms may not be present in water samples collected from deep wells) Doubled distilled water is used to wash all the glassware; instruments used and the sternum to avoid contamination.
- Fractures of Hyoidbone:
- In ward compression fracture.
- Antero posterior compression fracture.
- Avulsion fracture
- Inward Compression Fracture: Occur in throttling, due to grasping and squeezing using fingers of hands and palm. The posterior fragment is displaced inwards and the periosteum is torn on the outer side of greater horn or at the joint between the body and the greater horn of hyoid bone.
- Anteroposterior Compression Fracture: Occur in hanging and the posterior fragment is displaced outwards with tearing of periosteum on inner side of fracture. The fracture occurs in greater horn or at the joint of body and the greater horn. These fractures occur in karate blows on the front side of neck.
- Avulsion Fractures: Occurs indirectly due to traction in hanging. Mostly one greater horn is fractured outwards and the other inwards.
HEAD INJURIES
- Contrecoup Brain Injury
- Intracranial Hemorrhage:
- Epidural hemorrhage
- Subarachnoid hemorrhage
- Intracerebral hemorrhage
- Epidural hemorrhage: Occurs between the skull and dura mater, due to rupture of meningeal arteries. Mostly middle meningeal artery and its anterior and posterior branches get torn in fissure fractures on lateral side of skull, in temparo-parietal area of skull. Slow accumulation of blood forms nearly 2 to 3 cm thick, round blood clot causing compression of brain and unconsciousness. Epidural hemorrhage is arterial blood and is always traumatic. Anterior, middle and posterior meningeal arteries may be ruptured. Rarely, diploeic veins and venous sinuses may be damaged to cause hemorrhage in epidural space.
- Subdural hemorrhage: Occurs between the arachnoid and dura-mater due to tearing of bridging dura veins of venous sinuses and cortical veins. Bleeding is venous, it may be unilateral or bilateral, covering the cerebral hemisphere 2 to 3 mm thick and may gravitate to the under surface of brain. Subdural hemorrhage is also traumatic.
- Subarachnoid hemorrhage: Occurs between arachnoid and the piamater, commonly due to rupture of cerebral arteries. Spontaneous rupture of congenital berry aneurysm of circle of willis cause subarachnoid hemorrhage in young individuals and rupture may be precipitated by minor trauma to the head. A blow to the neck may cause rupture of vertebral artery inside the cranial cavity and cause subarachnoid hemorrhage and also close to the transverse process of first cervical vertebra due to its fracture. Mycotic aneurysms also cause subarachnoid hemorrhage from their rupture, but it is rare.
- Intra-cerebral hemorrhage: Occurs in brain tissue or in ventricles. In brain tissue punctate hemorrhage or large diffuse areas of hemorrhage may occur. Spontaneous rupture of lenticulo striate branch of middle cerebral artery due to atherosclerosis may give way and cause hemorrhage in internal capsule. Intra ventricular hemorrhage is the extension of parenchymatous hemorrhage, in hypertensive cerebro-vascular disease due to atherosclerosis. Punctate hemorrhages occur in boxers due to repeated punches on head and suffer from mental disorders known as ‘punch drunkenness’.
