Q3 LONG ANSWER 10M ★ High-yield

Describe putrefaction and the modifications of decomposition including adipocere, mummification and maceration.

Forensic Medicine · 2nd Professional — Para-Clinical

Autolysis and Putrefaction

Autolysis is self-digestion by the body's own enzymes, released from lysosomes after death; it is sterile and does not require bacteria, and is accelerated by heat and retarded by cold. It affects first the organs richest in enzymes — the pancreas, gastric mucosa, adrenal medulla and brain
Putrefaction is the bacterial decomposition of the body, chiefly by organisms from the large intestine — Clostridium welchii, coliforms, streptococci, Proteus and anaerobes — which spread along the vessels once the circulation has stopped. It is accompanied by colour change, gas formation and liquefaction

Stage and timing (temperate; much faster in India)	Findings
12 to 24 hours	Greenish discolouration of the skin over the right iliac fossa — the first external sign of putrefaction, appearing there because the caecum is superficial, thin-walled and full of bacteria. In INDIA it may appear within 6 to 12 hours in summer
24 to 48 hours	Discolouration spreads over the abdomen, then the whole body; marbling — a branching reddish-brown network along the superficial veins, produced by haemolysed blood and sulphmethaemoglobin, most marked on the shoulders, chest, groins and thighs
2 to 3 days	Gas formation — bloating of the face, abdomen, scrotum and limbs, producing the "bloated NEGRO" appearance in which the features are unrecognisable, the eyes and tongue protrude and the body may double in size. Crepitus on palpation
3 to 5 days	Blisters filled with foul reddish fluid; skin slippage, with the epidermis peeling in sheets — the hair and nails become loose and are shed, the "degloving" of the hands giving skin that can still be used for fingerprints. Purging of blood-stained fluid from the mouth and nostrils, which is commonly and wrongly reported as haemorrhage
1 to 2 weeks	Progressive liquefaction; the abdomen may burst; internal organs soften and liquefy in a characteristic order
Weeks to months	Skeletonisation — in India, in favourable conditions, a body may be reduced to a skeleton within a few weeks in the open, far faster than in temperate countries

Order OF putrefaction of internal organs — earliest are the larynx and trachea, the stomach and intestines, the spleen, the pregnant uterus, and the brain of an infant; latest are the prostate and the non-gravid uterus, which resist for weeks or months and may therefore be the last means of establishing sex
CASPER'S dictum — a body putrefies in 1 week in air = 2 weeks in water = 8 weeks buried in ordinary soil. The ratio is 1 : 2 : 8, and it is a rough guide rather than a rule
Factors accelerating putrefaction — warmth (optimum about 21 to 38°C), moisture and humidity, air, obesity, septicaemia and infection at death, injuries with open wounds, and death from asphyxia
Factors retarding it — cold (arrested below 0°C and above about 48°C), dryness, burial in dry sandy soil, deep burial, a coffin, haemorrhage and dehydration, poisoning by arsenic, antimony or zinc chloride (which have a preservative effect), and prematurity in an infant

CLINICAL PEARL

Green over the right iliac fossa is where putrefaction announces itself, and the reason is purely anatomical. The caecum lies immediately beneath a thin abdominal wall and contains the largest bacterial load in the body, so hydrogen sulphide from those organisms reaches the skin there first and combines with haemoglobin to form sulphmethaemoglobin. Everything else about decomposition varies with climate and circumstance; the starting point does not.

Adipocere

Adipocere (saponification) is the conversion of the body fat into a firm, greasy, waxy substance composed chiefly of saturated fatty acids and their salts, by hydrolysis and hydrogenation of neutral fat.

It requires moisture and warmth, and the absence of air — so it forms characteristically in bodies recovered from water, in damp graves and in sealed containers or cesspits. The water may be from the environment or from the body's own tissues
The bacterial enzymes of Clostridium welchii initiate the hydrolysis of fat into fatty acids, which are then hydrogenated to the saturated palmitic, stearic and hydroxystearic acids that make up adipocere
Appearance — a yellowish-white, greasy, waxy or crumbly material with a sweetish, rancid, ammoniacal odour; it floats on water, dissolves in ether and alcohol, and burns with a yellow flame. These simple properties confirm it at the mortuary
Distribution — begins in the subcutaneous fat of the cheeks, breasts and buttocks, where fat is abundant, and may extend to the whole body; it is commoner in obese persons, women and infants
Time required — the earliest changes appear at about 3 weeks, and adipocere is usually well formed by 3 months; in India, in warm water, it may be recognisable within 3 to 4 weeks
Its medicolegal value is that it preserves — the features, injuries and even bullet tracks are retained in the adipocerous tissue, so identification and the demonstration of wounds remain possible months or years after death. It also indicates that the body lay in a moist, airless environment, and gives a rough minimum time since death

Mummification and Maceration

Feature	Mummification	Maceration
Definition	Desiccation and drying of the body, with shrivelling and preservation of the tissues	Aseptic autolytic softening of a dead fetus retained IN utero in amniotic fluid
Conditions required	Dry air, high temperature and free circulation of air — a hot dry climate, a desert, a dry sandy grave, or a well-ventilated closed room. It occurs in rajasthan and dry regions of India	A sterile, moist environment — the fetus must be retained in the uterus with intact membranes and NO infection; if organisms enter, putrefaction occurs instead
Appearance	The body becomes dry, brittle, leathery and dark brown, greatly reduced in weight (to about a tenth), with the skin adherent to bone. There is NO odour	The fetus is soft, flaccid and flattened; the skin peels in sheets (skin slippage); the tissues have a reddish-brown colour; the skull bones become loose and override (spalding sign on radiography); and there are no gases
Time required	About 3 months in favourable conditions	Begins within 12 to 24 hours of intrauterine death; well developed by 3 to 4 days
Medicolegal value	Preserves the features, injuries and identifying marks indefinitely — identification and demonstration of the cause of death remain possible after years. Indicates the environment in which the body lay	Proves that the fetus died IN utero and was not born alive, which excludes infanticide; and the degree of change indicates how long the fetus was retained after death

CLINICAL PEARL

Maceration proves the baby was already dead before delivery, and that single finding can end an infanticide investigation. It requires a sterile environment, which exists only inside the intact uterus — so a macerated fetus cannot have breathed, cannot have been born alive, and cannot have been killed after birth. The Spalding sign on radiography, with overlapping skull bones, demonstrates it even before the delivery.

Decomposition in Water and in Special Situations

A body in water — putrefaction is delayed while submerged because of the lower temperature and reduced oxygen, but proceeds very rapidly once the body is recovered and exposed to air, which is a practical trap in estimating the interval
Washerwoman’S hands — bleaching, sodden wrinkling of the palms and soles, appearing within a few hours, progressing over days to loosening of the skin and finally degloving of the hand as a whole — from which fingerprints can still be taken
A body normally sinks and then refloats when putrefactive gases accumulate — in about 24 hours in summer and up to a week or more in cold water. This is why bodies reappear days after drowning
Adipocere is favoured in water; and in stagnant warm water, both adipocere and rapid putrefaction may coexist in different parts of the same body
Buried bodies — decomposition is roughly eight times slower than in air; a coffin, deep burial, dry sandy soil and cold retard it further, and bodies exhumed after years may be far better preserved than expected
The environment can produce opposite changes in one body — adipocere in the moist covered parts and mummification in the exposed dried parts, which is a recognised and initially confusing finding
Arsenic, antimony and zinc chloride preserve the body and markedly retard putrefaction, so a well-preserved body in circumstances that should have caused decomposition raises the possibility of chronic metallic poisoning

Applied Aspects

Do not report purged fluid as haemorrhage; blood-stained fluid from the mouth and nose in a decomposing body is a putrefactive artefact and is regularly mistaken for evidence of injury
Estimates of time since death from decomposition are very crude in India, because the rate is far faster than the temperate figures in every textbook; state the ambient conditions and give a wide range
Adipocere and mummification preserve evidence, so a decomposed body in either state should not be dismissed as uninformative — injuries, features and even bullet tracks may still be demonstrable
Look for the prostate and the non-gravid uterus in an advanced decomposition where sex is in question; they resist putrefaction longest
Deglove the hands and use the skin for prints rather than concluding that a decomposed body cannot be identified; and preserve a femur and a tooth for DNA in every case
Casper's dictum (1 : 2 : 8) is a rough guide only, and burial depth, soil type, coffin, clothing and season alter it substantially — but it is worth knowing because it explains why a buried body is so much better preserved than one left in the open
A submerged body decomposes slowly and then very fast once recovered; the interval is regularly underestimated on the appearance at recovery alone
Bodies sink and then refloat as gas accumulates — about 24 hours in Indian summer — which explains their reappearance days after a drowning
A well-preserved body in conditions that should have decomposed it raises the possibility of arsenic or antimony, which have a preservative effect
Maceration and putrefaction are mutually exclusive; the first needs sterility and the second needs bacteria, and the presence of one excludes the other
Adipocere and mummification can coexist in one body, in the moist covered parts and the exposed dried parts respectively — initially confusing but well recognised
Adipocere floats, dissolves in ether and burns with a yellow flame; these three properties confirm it at the mortuary without any laboratory
Autolysis needs no bacteria and putrefaction does, which is the whole reason a sterile intrauterine fetus macerates rather than putrefies
Both adipocere and mummification retain injuries, including bullet tracks, so such a body should never be dismissed as too decomposed to examine
Skin slippage gives usable fingerprints by degloving, and the loosened epidermis should be preserved rather than discarded with the washings
Look for the prostate and the non-gravid uterus in advanced decomposition; they resist longest and may be the only means left of establishing sex
Green over the right iliac fossa comes first everywhere, because the caecum is superficial and bacterially loaded; the timing varies with climate and the site does not

All questions in Death & Postmortem Changes

Every Forensic Medicine chapter →