Medico-legal Autopsy

MEDICO-LEGAL AUTOPSY
It is a post mortem examination of dead bodies to ascertain the cause of either unnatural or suspicious deaths.

Historical Background

It is not with surety when was the first medico-legal autopsy was held. But from the record, it is seen that Antistius, a physician, examined the body of Julius Caeser (100 –44 BC) and pointed that out of 23 injuries, only one injury in the chest was fatal. In 1374 AD, right to hold medico-legal autopsy was given by pope. But perhaps, the first systematic autopsy was held by Dr Ambroise Pare on the body of King Henry II in 1589.

Types

1. Pathological autopsy: It is usually done to conclude the cause of death in a case due to some pathological reason. This is not mandatory in our country (except in some institution and armed forces) without written consent from next of kin.
2. Medico-legal autopsy: It is done in cases of deaths which are sudden, suspicious and unnatural. It is mandatory and does not require any consent from the next of kin.
3. Anatomical autopsy: Done by medical students on embalmed dead bodies to enhance medical knowledge.

Types of Medico-legal Autopsy

1. Normal autopsy: Where a definite cause of death can be established in the post-mortem room from the findings obtained during the autopsy.
2. Obscure autopsy: Where no definite opinion as to cause of death can be given in the post-mortem room but can be concluded after receipt of further examination reports like a toxicological report from forensic science laboratory or histopathological or microbiological or biochemical reports.
3. Negative autopsy: In this type of autopsy, where no definite opinion can be given even after receipt of other reports, namely Forensic State Laboratory report, histopathological report, etc. and for example vagal inhibitory death, metabolic death like sudden hypoglycemia, hyperglycemia etc.

Conditions where Medico-legal Autopsy is Indicated

1. In all cases of deaths where the cause of death is not known.
2. In all cases of deaths which are unnatural, namely homicide, suicidal or accidental.
3. In all cases of deaths which are sudden and suspicious.
4. In all cases of deaths which have occurred in police or judicial custody.
5. In case of death of a person whose identity is not known.
6. In all deaths which have occurred during a surgical operation.
7. Alleged dowry deaths in term of Sec. 304B and 498A I.P.C.

Different Techniques of Autopsy

1. Technique of R Virchow: In this techniques organs are removed one by one. This method has been used very commonly with some modification, the first step being opening the cranial cavity.
2. Technique of C. Rokitansky: This is characterized by in situ dissection in part, characterized by embloc removal.
3. Technique of A. Ghon: In this, cervical, thoracic, abdominal and urogenital system are removed as organ block and then dissected. Modification of this technique has become very popular.
4. Technique of M. Lettule: Thoracic, cervical, abdominal and pelvic organs are removed en mass and subsequently dissected en block. Of all the techniques this technique is by far the best because there is scope for inspection and preservation of connection of organs and organ system

Procedure
Medico-legal autopsy can only be done at an authorized place, usually in sub-divisional and district level or in medical colleges in Forensic Medicine Dept. in subdivision and district hospitals. Post-mortems are done by doctors of different disciplines other than forensic medicine experts, hence are not above questions. But, in medical colleges, the post-mortem is being done by experts.

The post-mortem is being done on receipt of a requisition giving brief facts of the case or an inquest, with challan in duplicate, through an identifying constable. Only after the body is being identified by the authorized constable, the post-mortem can be held.

In this connection, it must be kept in the mind that the body for medico-legal autopsy is the property of the police and disposal of the body is the responsibility of the police.

Medico-legal Reports
Report consists mainly of the following three parts, namely:

1. Preamble/introduction
This states about the authority ordering the examination, time of arrival of dead body at mortuary, date, time and place of examination, name, age, sex of deceased and the means by which the body was identified.

2. Body of reports/facts observed on examination
This part of report contains detail description of examination (external and internal) of body, with exact measurement and description of injuries, assisted with essential diagrams.

3. Conclusion
A conclusion is drawn as about the cause of death after consideration of various points observed during post-mortem examination.

The report should be to the point, without vagueness or doubt. The formed opinion should be purely scientific and honest. It is usually not admitted as evidence unless the concerned doctor attends the court and testifies the facts under oath. The defense can cross-examine the medical officer over the report.

Purpose

1. To establish the identity, in cases were not known.
2. To detect the cause of death whether natural or unnatural.
3. Detect the nature of death, suicidal, homicidal, and accidental in case of unnatural death.
4. Estimate the time of death and time elapsed since death.
5. In case of a newborn, to ascertain whether the newborn was born dead/stillborn or died after birth.
   
   

Set laws/Codes

1. Official requisition (inquest report) authorizing Medical officer for the purpose of autopsy from police, magistrate, or coroner must be obtained.
2. Autopsy is always carried out in mortuary, which is a place especially designed for this purpose. However, exhumation is an exception, where autopsy can be conducted in open space near the grave but it should be screened.
3. Undue delay should be avoided. Even in decomposed bodies autopsy should be conducted as it may still reveal details of important lesions.
4. Medical officer should first go through the inquest report carefully to find out the evident cause of death as judged by the appearance of dead body and its surroundings, to collect all details regarding the case from the case sheet and accident register. Therefore, attention may be given to salient points, while doing the post- mortem examination.
5. Examination should be conducted in daylight, because of the color change in jaundice, bruises, changes in post-mortem staining, etc cannot be valued in artificial light. If the body is received late in evening then a preliminary examination noting the external appearance, temperature, any injury, extent of post mortem lividity and rigor mortis of the body is noted. The actual examination is to be conducted the next day in daylight.
6. Identification of the body is very important. Police constable who accompanies the body must identify the body. Names of those who identify the body must be noted. In unidentified bodies, marks of identification such as tattoo marks, photographs, fingerprint and footprint must be noted.
7. Unauthorized person should not be present in mortuary, except the concern police officer.
8. Findings of autopsy should be noted with sketches of all important injuries.
9. Every organ should be examined carefully.
   
   

Cause of death

After completing the autopsy, a complete and concise report should be written in triplicate using carbon papers. Sealed copies are sent to Magistrate and investigating officer. Third copy is retained for future reference. A definite conclusion about the cause of death is to be mentioned in report, but when in doubt, it should be mentioned that without histological, chemical, bacteriological examination, absolute opinion could not be formed.

EXTERNAL EXAMINATION
It is detailed head to toe description of the examination of naked body noting general features of dead person like sex, age, color race, deformities, nutrition, hair, scars, tattoo marks and moles, etc.

Method of carrying external examination

1. Clothing should be listed, while examining. Various conditions of clothes like tear and disarrangement of buttons indicating struggle. Cuts, holes, burns and blackening from weapon like gun should be noted and compared with injuries of body. Stains as of blood, semen, vomits, grease, poison, should be preserved for analysis after noting the odor. Clothes should be removed with care, without any tear to avoid confusion with sign of struggle and if necessary, they should be cut along the line of stitch.
2. General body stature like height, weight and nutrition is noted.
3. Condition of skin, its color, injuries like bruises, petechiae should be noted. Any stain on skin as on clothing should be noted. Conditions like edema of legs, surgical emphysema about chest, skin of face is examined for its expression, cyanosis, petechiae, hemorrhages and exhaustion, etc.
4. Saliva swab is always taken.
5. Nails are to be scrapped before removal of clothes. Substances like hair, other matter adhering on them should be removed with help of matchstick. Ten small envelopes are to be made and labeled, one for each finger and after which scraper is dropped, preserved and sealed in a separate envelope.
6. Hair should be examined and any foreign substance should be removed with forceps, if necessary combing of hair can be done. Hair from atleast six different sites of scalp are examined, both cut and pulled sample are taken and labeled.
7. To assess the time elapsed since death, special points like rigor mortis, putrefaction and post mortem lividity should be noted.
8. Swabs from vagina, rectum and areas that have the likelihood of being stained by seminal fluid in cases of sexual attack are to be taken.
9. Skull is palpated in trauma like fractures, injury and any swelling.
10. Eyes are examined and condition like, softening of eye balls, color change of sclera in case of jaundice, lens opacities and opacities of cornea, extravasations of blood or hemorrhage may change the color of pupils and peri-orbital tissue.
11. Neck is examined and any injuries like bruises, fingernail abrasions, ligature marks or degree of distension of neck vessel are noted.
12. Lymph nodes like cervical, axillary and inguinal should be examined.
13. Thorax including breasts should be examined, for shape and symmetry and condition like fracture of ribs.
14. In abdomen, features like hernias, visible veins, discoloration, and pigmentation like striae gravidarum are looked for.
15. Back should be examined for bedsores, post-mortem staining.
16. External genitals should be examined, its development and position of testis. Mutilations and edema, which may be due to putrefaction is noted.
17. Natural orifices such as mouth, ear, nostrils, vagina and anus are examined for blood, foreign material, froth, the odor of alcohol. If the mouth is difficult to open then cheeks are incised, to view and examine the teeth and cavity. Condition of the tongue, its relative position to teeth, any bite marks or bruising is to be noted. In addition, marks of corrosion or injury to lips, gums and teeth are noted while examining.
18. Position of limbs, in particular arms, hands and fingers are to be noted. The hands are examined for abrasion and cuts. Limbs should be palpated and suitable movements are done to assess any fracture or dislocation, which is further confirmed by dissection.
19. External wound should be systematically examined. Each wound should be described under headings like the site, length, breadth, depth, edge, direction, and nature. Condition like the existence of foreign substance, clots of blood, in the wound and any extravasations of blood, into nearby tissue is noted. Caution is to be taken while handling of deep and penetrating wounds as they should not be probed until the body is opened. In burn cases, position, nature, extent and degree of burn is noted. Injuries may be assisted with required sketches and photographs. All external injuries on the body are to be compared with those mentioned in the inquest report and discrepancies should be stated in the autopsy report.
20. List of articles removed like clothes, bullets, wallet, ring and other jewellery from the body is to be made. They should be labelled and mentioned in the report. All these things are sealed and handed over to the constable after receiving a receipt of the same.

INTERNAL EXAMINATION
The internal examination is systematic description of the natural disease and it does not include recent injuries. Negative observation like no pulmonary emboli, no significant coronary artery atherosclerosis and no skull fracture are to be included in the report. All viscera and cavities of body should be examined systematically.

Incisions
There are 3 types of incisions:

1. ‘I’ shaped incision or the vertical incision: An incision extending from the chin straight down the symphysis pubis, passing on either side of umbilicus. The soft tissues are removed sidewise. The chest cavity is opened by cutting along costal cartilages and the sterno-calvicular junctions are cut to remove the sternum with costal cartilages. Now an incision is given along lower border of mandible and cervical organs from tongue are dissected down up to thoracic cage and the composite visceras are taken out. Similarly the abdominal and pelvic visceras are taken out and examined
2. ‘Y’ shaped incision: This begins near the acromial process of the clavicle. From here it extends down below nipples and across to the xiphoid process. A similar incision is made on other side of the body. From the Xiphoid process, incision is carried down towards the pubis. It gives wider area for examination.
3. Midline incision: A midline incision extends from suprasternal notch downwards to symphysis pubis and upwards it extends over clavicle to its centre and then passes upwards over the neck behind the ear ending at the mastoid tip on each side. This type of incision is given in cases of hanging, throttling and strangulation.

Detail Examination

1.  Abdomen
Abdomen is incised from xiphisternum to symphysis pubis.
Following points are observed before disturbing any organ.

1. Thickness of fat in the wall.
2. Peritoneal cavity is observed for, like presence or absence of blood, pus or fluid.
3. Perforation of any organ is noted.
4. Mesenteric and omentum fat is noted.
5. Any abnormality of position of organ is described.
6. Peritoneum is examined for signs of inflammation, exudation, adhesions and congestions.

After observing these points, each organ is individually examined for shape, size, surface, consistency and cut surface is noted and status recorded.

1. The content of the stomach and esophagus are examined for presence of any food. If present, its state of digestion, smell, color, character are noted, mucus membrane is checked for ecchymosis, hemorrhage, ulcer, etc. and condition like varices and stenosis is noted.
2. Intestines are examined for congestion, inflammation, erosion, ulcer, perforation and contents.
3. Liver is cut into slices each slice, being 2 cm thick.
4. Spleen, the vessels at hilum are cut and organ is separated. Presence of accessory spleen is always looked for.
5. Pancreas is to be removed with stomach and first part of intestines.
6. Kidneys and ureters are examined for inflammation, calculi or debris.
7. Haemorrhage in adrenals is specially looked for. They are identified with relation to upper pole of kidney.
8. Condition of bladder wall is to be looked for. Stored urine is looked for its amount, color, character. Time elapsed since death can be determined by the amount of urine passed.
9. Presence of prostate is confirmatory of male sex. As it can resist putrefaction for longer period, therefore it can be recognized in highly decomposed body. Any tumors, benign or malignant is looked for.
10. In testes presence of clotted blood inside scrotum or around testis are noted. It is surest sign of male sex.
11. While examination of female genital, age of fetus in pregnant female can be determined by size of uterus. Any kind of injury/ trauma may be indicative of rape prior to death.

2.  Neck and Thorax

1. Esophagus, larynx and trachea are examined after cutting them open through posterior surface. Blood, mucus, vomited matter, foreign substances are noticed for their presence. Tongue is noticed for teeth marks or laceration.
2. While examining heart, first the pericardium is opened and the outside of the heart is examined. Any fluid, pus, blood is examined and measured. Heart is dissected along the direction of flow of blood in it. Aorta is examined for chronic aortitis or atheroma formation.
   1. Agonal thrombi: Person dying slowly often form, tough, string like yellow thrombus in right side of the heart. They usually begin in atrial appendage and then extend to the right auricle and ventricle. Formation of agonal thrombi in left ventricle is not extensive.
   2. Post-mortem clots: These are moist, smooth, and homogenous, attached loosely or not attached at all to underlying walls and there are no lines of Zahn. They are of two types, firstly when clotting appears rapidly they produce soft, lumpy, dark red, slippery, moist substance is produced (red currant jelly). Secondly when clotting starts after red cell sedimentation is over, a clot similar in character to first type is formed at bottom. Above the clot a pale yellow layer of serum and fibrin is formed (chicken-fat). The fibrin clot is soft and jelly like but may be elastic when amount of fibrin is greater.
   3. Unclotted blood: In cases where death is sudden, clotting of blood is greatly reduced. Blood is fluid in certain cases like septicemia, poisoning like carbon monoxide (CO), death from asphyxia, hypofibrinogenemia due to amniotic fluid embolism, retained placenta or pleural sepsis.
   4. While examining lungs, pleural cavities should be examined for the presence of adhesions, foreign bodies, fluid or blood. Lungs are examined for presence of foreign bodies, consolidation, edema, emphysema, atelactasis, congestion, Tardieu’s spots, emboli, etc. Amount of blood flowing into cavity of chest from large vessels is noted. Pneumothorax is to be demonstrated before the chest wall is opened.
      
      

3.  Head
A wooden block is placed under shoulders so that the neck is extended and head fixed with help of headrest.

Incision is given in the following manner :

1. Over skin: A transverse incision is given across the vault from one ear to the other and skin flaps are separated anteriorly and posteriorly. Periosteum is also incised by a criss-cross incision and separated.
2. Over bone: The skull bone is either sawed or chiselled and the skull cap is removed.
3. Removal of brain: Meninges are cut along the line of bony separation. The falx cerebri is cut, the frontal lobe is lifted up, the nerve attachments are separated, falx cerebelli is cut, the cerebellum is secured and the brain is separated by incising the medulla and taken out.
   1. Any bruising of deeper tissue of scalp is noted.
   2. Meninges are observed for congestion, extradural, subdural, or intracranial haemorrhage.
   3. Superior longitudinal sinus is examined for any antemortem thrombus.
      (a) The brain is looked for haemorrhage, injury or any disease. Cerebral vessels are noted with special preference to urean ‘circle of willis’. Basal skull fractures are to be looked after stripping of dura from base of skull.
      (b) Spinal cord is not routinely examined unless there is any indication of disease/injury. The vertebral column is examined for fracture and dislocations. Examination of the spinal cord is very much necessary in cases of strychnine poisoning.

4.  Limbs
Limbs are examined for fracture and marrow is taken from the femur. Vessels in the limbs are noted.

5.  Reconstitution of the body
An important aim after autopsy is to reconstitute the body such that it can be viewed, if desired, by relatives of the deceased. After the examination, the body has an open and empty chest cavity with chest flaps open on both sides, the top of the skull is missing, the skull flaps are pulled over the face and neck. It is unusual to examine the face, arms, hands or legs internally. The organs are replaced and any excess space is packed with cotton, cloth, etc. The chest flaps are closed and sewn back together and the skull cap is sewed back in place. Then the body may be washed with water, dried and wrapped in a shroud. The body is then handed over to the police constable accompanying it for disposal.

EXAMINATION OF SKELETAL REMAINS

Sometimes the police may send some bones for medico-legal examination and report. Before actual examination, care should be taken to note the condition of the bones, apparels, etc. adhering to the skeleton. They should be examined and preserved. The bones should be arranged in a proper anatomical order and examined carefully.

Opinion on the following medico-legal points can be given:

1. Origin of skeleton is to be determined; human or animal. Done by using anatomical knowledge and if confused, serological techniques should be applied for confirmation.
2. If skeleton belongs humen being than it should be confirmed as to how many individuals. This can be done by arranging the bones in anatomical order.
3. Opinion that it belongs to single human can be based on the following points:

Data for Identification

1. Age: By bony fusion, teeth, and cranial suture fusion.
2. Sex: By noting the sexual characteristic in individual bones.
3. Race: By noting the cephalic index.
4. Stature: From long bones, it can be calculated by using the formula of Glessor and Trotter or Karl Pearson.
5. Congenital or acquired bony deformity – if any.
6. From the skull: Superimposition photography or facial reconstruction may be tried by forensic scientist to fix up absolute identification.
7. From DNA profiling now absolute identification is possible.

Data for Fixing Time Passed Since Death

Time passed since death may be calculated, considering the weather condition, the place of recovery of bones, possibility of the soft tissues being eaten up by predators etc. If the bones appear to be very old, radiocarbon dating by using Neutron Activation Analysis technique is to be done.

Cause of Death
Presence of any antemortem injuries over bones by foreign bodies like a bullet or a splinter will help to fix up the cause of death. In suspected cases of metal poisoning – portion of bones may be preserved for toxicological examination.

Nature of death: From the findings it may be possible to give definite opinion as to whether the death was homicidal, suicidal or accidental.

Reference: A Handbook of Forensic Medicine and Toxicology by Dr Madona Joseph & Dr Harpreet Kaur