POST MORTEM ARTEFACTS(forensic medicine)

post-mortem artefacts
forensic medicine and toxicology.

1. POST MORTEM ARTEFACTS : BY: DR.PURILE KUMAR DAS MODERATOR: DR. MOHAN KUMAR HANSDA 1

2. An ARTEFACT is any change caused or feature introduced in a body after death (accidental or physiologically unrelated finding to the natural state of the body). It is a structure or substance, normally not present, but produced by some external agency or action. They are important because they are likely to lead to MISINTERPRETATION of medicolegally significant findings by an inexperienced pathologist. 2

3. ARTEFACTS INTRODUCED BETWEEN DEATH AND AUTOPSY : AGONAL ARTEFACTS: Regurgitation and aspiration of gastric contents – in respiratory tract after death may be confused with genuine antemortem aspiration. 3

4. RESUSCITATION ARTEFACTS: The injection marks of resuscitation are usually found in cardiac region or on the extremities. A defibrillator applied to the chest may produce ring like contusion. Ribs and sternum may be fractured during CPR. Resuscitative contusion of soft tissues of neck can raise suspicion of homicidal strangulation e.g. Trying to introduce rope into airway. 4

5. DEFIBRILLATOR MARKS SIMULATING ANTEMORTEM ABRASIONS ON CHEST: 5

6. ARTEFACTS DUE TO HANDLING OF BODY : Occasionally, fracture of ribs or bones or extremities may occur by rough handling of body, especially. They are commonly introduced during straightening of the limbs during rigor mortis. An occipital contusion may be caused if corpse is allowed to fall on a hard surface. UNDERTAKER’S FRACTURE is a subluxation of the lower cervical spine due to tearing of intervertebral disc at about C6-C7. 6

7. ARTEFACTS DUE TO RIGOR MORTIS: Rigor may be partially broken due to handling of body, which may lead to misleading in time of death. Onset and duration of rigor may be altered by atmospheric conditions like extreme heat or cold, or antemortem conditions like muscular diseases, hypothermia, exhaustion or wasting diseases. 7

8. ARTEFACTS RELATED TO POST MORTEM LIVIDITY: Colour of PM stains is usually bluish purple. Certain poisons may change the colour in hypostatic area e.g. cherry red colour in CO poisoning, bright red colour in HCN poisoning, chocolate colour in potassium chlorate, nitrite, aniline poisoning etc. Banding of the oesophagus may be seen especially when the tissues are congested. Bands are pale areas in the mucosa caused by post mortem hypostasis being prevented from settling by external pressure of adjacent anatomical structure can be an unmistakable sign of strangulation(for an inexperienced pathologist). Large petechiae, sometimes with raised blood blisters maybe seen in dependent skin of persons who have died a congestive death, or when upper part of the body hangs down after death. Face may show haemorrhages when head is dependent. 8

9. Cherry-red PM hypostasis in CO poisoning: 9

10. ARTEFACTS DUE TO BURNS : An unburnt groove around the neck due to tightness of clothes (collar) may resemble a strangulation mark. In severely burnt bodies, fat droplets may be found in pulmonary vessels which must NOT be mistaken for fat embolism. 10

11. ARTEFACTS IN FIREARM WOUNDS: In decomposition, there may be peeling of skin and loss of hair and gunpowder from the skin around an entrance wound. Margins of an entry wound may become ragged due to disintegration of the tissue at the margins, and it becomes difficult to distinguish entry wound from exit. Sometimes an encapsulated bullet may be unexpectedly in the body which may be due to an old injury, whereas the actual cause of death may be something else. 11

12. ARTEFACTS DUE TO ANIMAL AND INSECT BITES: Injuries caused by crabs could, rarely resemble stab wounds. Rodents bites are usually circular, or wedge shaped with finely serrated margins, showing irregular edges. Extensive linear ant lesions represent ligature strangulation. 12

13. ARTEFACTS IN BRAIN AND LIVER : Regional flattening of cerebral convolutions is a PM artefact. Seen generally in occipital lobe which is in contact with the cranium. Rough removal of brain may cause artificial damage to ponto - medullary junction or to midbrain pons junction. The undersurface of liver shows greenish coloration due to bile, but appears to be due to putrefaction. 13

14. POST MORTEM HEMMORHAGE: After death blood may collect in pleural cavity due to wounds produced on chest wall and lung tissue. After death, blunt impact may lacerate blood vessels and displace red cells into tissue spaces. 14

15. ARTEFACTS DUE TO HAIR : Beard may appear to grow, after death, whereas growth of hair stops after death. The cause of this PM apparent growth of beard may be shrinkage of skin, due to which greater part of the hair shaft is exposed above the epidermis. ARTEFACTS DUE TO DECOMPOSITION: Intense localized lividity of skin due to hypostasis or displacement of internal pools of blood by pressure of gases of decomposition produces pseudo bruises which may simulate ante mortem bruises . The blood becomes darker in decomposition, due to which brain, heart, lungs, become congested which may be mistaken for signs of asphyxia. 15

16. HYPOSTASIS LIKE BRUISE: 16

17. SI.NO ARTEFACT MISINTERPRETATION 1. Blood stained from mouth and nose Death due to haemorrhage. 2. Post mortem blisters Antemortem blisters due to burns or scalds. 3. False groove over neck due to tight collar Strangulation marks. 4. Small round holes produced by maggots Bullet holes 5. Tanning of skin of face and neck due to regurgitated gastric juices Antemortem burning. 6. Separation of sutures of skull in a child due to gases of decomposition in brain and protrusion of abdomen Trauma 7. Decomposing pancreas Haemorrhagic pancreatitis 17

18. IMAGE OF POSTMORTEM AND ANTEMORTEM BLISTERS: 18

19. GUNSHOT APPEARING WOUND, MADE BY MAGGOTS: 19

20. ARTEFACTS DUE TO CHEMICALS & REFRIGERATION : In automobile accidents or airplane crashes exposure to gasoline causes postmortem detachment of epidermis. On exposure to air, the underlying dermis gives a yellow brown colour base, resembling thermal burns or abrasions after death. Pink hypostasis is seen in bodies kept in cold storage which may resemble CO poisoning. 20

21. IMAGE OF HYPOSTASIS IN REFRIGERATED BODY : (PINK COLOUR)

22. EMBALMING ARTEFACTS: The trocar wound may stimulate a stab wound. Some blood may be forced out of injured blood vessels due to pressure and may get collected in tissues and maybe mistaken due to antemortem haemorrhage. The trocar may also disturb the track of bullet/ weapon and produce false tracks. A homicidal stab wound may be enlarged by the embalmer to approach an artery or he may pass a trocar through a gunshot wound. 22

23. TROCHAR INSERTION FROM NECK AND ABDOMEN: 23

24. INTERMITTENT & EXHUMATION ARTEFACTS: In bodies which have been buried, fungus growth is usually seen at body orifices, eyes and at the sites of open Injuries. After removal of fungus, the colour of underlying skin resembles bruising. Grave-diggers can produce PM fractures, abrasions and lacerations. EXHUMED BODY: 24

25. TOXICOLOGICAL ARTEFACTS: Faulty collection and faulty preservation of samples. When blood is collected from heart with a long needle, it may be contaminated with stomach contents or regurgitated oesophageal contents. If blood is contaminated with pericardial or pleural fluids, false results are obtained as regards alcohol, because significant diffusion of alcohol occurs after death from stomach to pleural and pericardial fluid. 25

26. ARTEFACTS INTRODUCED DURING AUTOPSY : 26

27. AIR IN BLOOD VESSEL S: Air may enter veins of neck during reflection of skin, leading to erroneous diagnosis of air embolism. SKULL FRACTURES: Fracture of skull may be produced due to partial forceful pull of skull cap or by using chisel and hammer to loosen skull cap. This may produce additional fractures or may cause extension of already present antemortem fractures. 27

28. VISCERAL DAMAGE : Rough handling of brain during removal may produce tears of the midbrain. Rough handling of liver during removal may produce tears of diaphragmatic surface, which may simulate antemortem laceration. Neck structures may be torn during autopsy to drag out thoracic viscera. 28

29. EXTRAVASATION OF BLOOD : In case of suspected cranial injury, first the neck and chest should be opened as it decompresses the CVS drainage.If blood has not been drained from vessels of head, damage to dura and dural venous sinuses on removal of skull cap may lead to an escape of blood into the subdural space, simulating an antemortem sub dural hemorrhage. 29

30. FRACTURE OF HYOID BONE, INJURY TO BLOOD VESSELS AND TOXICOLOGICAL ARTEFACTS : When the tongue and neck structures are firmly grasped and pulled upon while removing neck organs, hyoid bones and thyroid cartilage may be fractured , especially in old people. While dissecting neck structures, toothed dissecting forceps may damage intima of carotid artery resembling a tear in strangulation. Toxicological artefacts may be due to contamination of viscera with stomach contents during autopsy or by putting all organs in one container or by using contaminated containers , or by faulty technique in collecting sample or faulty storage/ usage of preservatives. 30

31. REFERENCES:- 1.DR K S Narayan Reddy/Artefacts/ 2022/ Jaypee brothers medical publishers Pvt Ltd 2. DR Anil Aggarwal/2nd edition/Artefacts/2022/APC Publishers Ltd 3. Krishna Vij/Textbook of Forensic Medicine and Toxicology/5 th edition/Artefacts 4. Pekka Sauko , Bernard Knight/Knight’s Forensic Pathology/4 th edition/CRC Press/2016 5. Tedeschi, Eckert and Tedeschi/Vol II/EWP/2016 31

32. 32