IDENTIFICATION
Identification is the establishment of the individuality of a living or dead person.
1. Criminal identification: in crimes the police identifies assailants
through: fingerprints, photographs and by witness, who may be asked to point out the accused. Identikit is a composite picture of a person from a witness account.
2. Civil identification: in courts.
3. Personal identification: of dead persons by their relatives or friends.
4. Legal identification: of dead or living persons.
Medicolegal circumstances of Identification of a living person are:
I, For medical purposes:
unconscious patient, patient with true amnesiathose with mental confusion
2. For civil purposes: in problems of inheritance, at marriage,on employment or immigration, in cases of disputed paternity, on call for the military service
3. For criminal purposes: in sexual offences e.g. rape, in kidnapping, to determine the criminal responsibility
Medicolegal circumstances of identification of a dead person are:
A missing person and presumed dead. To issue a death certificate and allow burial. In accidents, In crimes, In mass disasters.
Mass disaster is an event in which nine or more persons are killed. They
may be due to natural causes e.g. floods, earthquakes andvolcanoes and here the number are usually thousands . Massdisaster may be also due to unnatural causes (man-made) e.g. airplanesaccidents, train accidents, explosions and falling of buildings.
METHODS OF IDENTIFICATION OF A LIVING:
Sex, age, stature and race are usually self evident however the following points are the scheme to be followed:
1. General appearance:Weight, Height, Color of Skin, Hair,
2. Features: Face, Eyebrows, Color of iris, Chin, Nose, Configuration of the ear (Bertillon stated that the ear is a prominent individual character that differs from one to another). Now ear print.
3. Personal characters: Voice, Speech, Mental power , Education, Handwriting, Gait
4. Clothing helps to denote the occupation and the social status.
5.Age
6.Sex
7. Blood groups
8.Prints
9. Congenital anomalies or developmental defects, e.g.
* Asymmetry * Harelip.
* Cleft palate * Polydactyly
10.Birth marks or naive,
11- Scars: due to previous trauma, operations or physical injuries. When a scar is first formed it is reddish or bluish and tender, with time it contracts and becomes more dense, white and shiny. Even when old it becomes evident on friction.
12.Tottoos: which are performed by pricking pigments or ink under the skin with a needle. It is permanent unless the skin and underlying
subcutaneous tissue is removed either surgically, by burns or by corrosives, Tattoos can give an idea about the name, address, religion, armed force serial number or name of the loved one.
13.Photographs.
METHODS OF IDENTIFICATION OF A DEAD:
A recently dead body is usually the ease, but sometimes decomposingbodies, fragmentary remains or skeletal remains are the question foridentification. We look for:
1. Features: as mentioned before.
2. Jewelry: as rings, bracelets, necklaces and earrings in addition to watches, lighters, pens and keys. Careful examination may reveal useful data as symbol or name,
3. Documents: including personal papers, photographs, identity cards, credit cards and similar items in a wallet or handbag.
4. Clothing provides a clue to the social status and occupation of deceased,
5. Contact traces usually give occupational data which may be recent or temporary e.g. paint, grease, flour and dyes.
6. Height or stature: From the skeleton; there are mathematical formulae applied to the length of the long bones to calculate the stature. Pearson’s formulae are thecommonly known,
7. Weight
8. Sex
9. Age
10. Race
1 l.Blood groups
l2- Prints
13.Teeth examination
14.Developmental or congenital defects:
e.g. * Harelip * Cleft palate * polyciactyly
* Abnormal bones, sesamoid bones. bicepital ribs.
15. Scars: The normal pattern of skin will not return after scar formation.
Suspected scars in the dead can be proved by microscopy with the aid of
special stains.
16. Tattoos: Clues to the victim’s identity are often present in the design
of tattoos.
17. Hair: peculiarities of hair; color, style, dyed, length, curly, bald,
being cut or crushed and the presence of foreign material. Sex can be
determined by examining the root sheath for the sex chromatin. Blood
grouping can be performed on hair root.
18. Handedness: Usually there is an increased muscle development in thedominant limb and in their length.
19. Internal physical examination and medical appliances:-
* Underlying disease.
* X-ray of the whole body may reveal:Old fracture.Prosthesis e.g. plates or nails in joints and bones.Pacemakers implanted to provide proper heart rhythm and rate, can give idea about the model, manufacturer and serial number and hence personal identification.Artificial Valves.
20. Data from the skull, if previous X- ray is available:
- Frontal sinus: now it is believed that no two persons have the same pattern of the frontal sinus. This should be done in ages above 15 after the full development of the frontal sinus.
Sellaturcica.
- Skull suture pattern e.g. sagittal and lambdoid sutures.
- Vascular grooves in the skull e.g. middle meningeal vessels.
21. Superimposition of skull and antemortem facial photographs.
22. Facial reconstruction:
The purpose of facial reconstruction is to produce an image from a skull
which offers a sufficient likeness of the individual. The traditional method was by using clay or plasticine to build up the soft tissue of the skull; tissue depths. are known for landmark sites on skull. Recently computerized methods for 3D facial reconstruction have been developed. Computer programs can transform laser-scanned 3D skull images into faces.
23. The time that the body or bones have been buried can be calculated using immunological techniques and radioactive materials
1. Identification of sex
1. Presumptive data about sex are:Features, General contours,
Clothes and voice
2. Probable signs: The breast, the muscle development, the distribution of body hair and subcutaneous fat, the external genitalia
The certain signs of sex determination are:
• the presence of gonads (testes in males and ovaries in females)
• the sex chromatin tests.
The identification of sex is of special importance in the problem of intersex.
Sex chromatin Test (Nuclear Sex):
Female cells usually show collection of chromatin material (due to X chromosomes) on the inner surface of nuclear membrane. These can be demonstrated on cells of buccal mucosa as Barr bodies. A drumstick appearance is seen in the female neutrophils (Davidson bodies).
Type of intersex
1-Gonadal agenesis: where there are no sex organs at all and the nuclear sex is negative.
2-Gonadal dysgensis : where the external sex structures are present but no ovaries or tesres e.g. Kleinfelter,s syndrome with external features of a male and Turner,s syndrome with those of a female.
3. True hermphrodite: when both ovaries and testes are present. The nuclear sex is positive.
4.Pseudohermaphrodite The external genitalia cannot determine the sex and the gonads and the nuclear sex give the true sex.
Identification Of Sex From Bones:
The pelvis, sternum and skull are the main bones that help in identit3’ing sex as they show definite differences between males and females
However, by applying some measurements, the sex of the femur and humorous can be determined.
The articular surface of the head of the humerus is larger in males. The distal end of the shaft of the femur is less inclined in males than in females, (by measuring the degree of the angle between the axis of the shaft and that of the articular surface).
The pelvis:
The pelvis of the a female is generally wider and shorter than that of a male .
Male Pelvic / Female Pelvic*Bones
*Body qf pubis
*Pubic arch
(subpubic angle)
*Greater Sciatic notch
*Obturator foramen
* Preauricularsulcus
Iliac crest
* Pelvic cavity
Iliopectineal line
*Acetabulum
*Pubic /ischinm ratio
Sacrum
Articulation surface of sacrum / Bones are massive , rough and heavy
Triangular
Acute angle i.e. less than90°
Deep and narrow
Oval
Absent
Prominent and highlyCurved
Deep, Straight walls
Rough and prominent
Wide, looks laterally
Less
Long, narrow, homogenous curve
2 1/2 segment / Smaller, lighter and smoothand generally wider.
Quadrangular.
Obtuse i.e. more than 900
Shallow and wide
Smaller and more triangular
Well defined especially in multipara
Less prominent, less curved
Shallow, wide wall curved outwards
Smooth, less prominent
Narrow, looks laterally and forwards
Greater.
Short , wide , curved
only at lower end
1 1/2 segment
Male skull / Female skull
Size and weight / Bigger and heavier / Smaller &less weight
Superciliary arch / Marked / Less marked
Fronto-nasal junction / Angular / Rounded and smooth
Parietal and frontal eminences / Prominent and rough / Less prominent and smooth
Mastoid process / Bulky and rough / Smooth and less marked
Muscle attachments / Rough / Smooth
Candylar facets / Long and narrow / Short and wide
The sternum
The female sternum is short and broad. the body is less than double the manubrium. The male sternum is long and narrow. The body is more than double the manubrium. The junction between the body and the manubrium is angular or prominent .
II. Identification of age
The estimation of age is done by X-ray in the living and by exposure and
dissection in the dead through:
1. The eruption of teeth (deciduous and permanent) and shape of mandible.
2. The appearance of centers of ossification.
3. The union of epiphyses.
4. The closure of fontanels.
5. The fusion of sutures.
6. The level of the medullary cavity.
1. A.. Eruption of teeth:
Deciduous teeth:
- Central incisors: 6 months
- Lateral incisors: 9 months
- Canine: 18 months
- First molar: 12 months
Second molar: 24 months
Permanent teeth:
- First molar: 6 years
- Central incisors: 7 years
- Lateral incisors: 8 years
- Canine: 11 years
- First premolars: 9 years
- Second premolars: 10 years
- Second molars: 12 years
- Third molar: At any age above 17 years.
B. Mandible:
The angle between the body and ramus is obtuse in infants, right in adults and obtuse in old age.
Adult infant
2. Appearance of ossification centers:
A. During intrauterine life:
At 5 months: Calcaneus
At 7 months: Talus
At 8 months: Distal end of femur
At 9 months: - Proximal end of tibia
- Cuboids
- Distal end of femur becomes ‘/2 cm in diameter
B- After birth:
At 3 months: 1) The head of femur
2) The distal end of tibia
At 6 months: The distal end of fibula
At 7 months: 1)The greater tuberosity of humerus,
2)The distal end of die radius
At 2 years : The proximal end of fibula.
At 3 years: The greater trochanter of femur, the proximal end of radius
At 5 years: The medial epicondyle of the humerus, the distal end of ulna.
3-Union of epiphyses: (NB. In females they fuse 2 years earlier )
A-Upper limb:
-At 7tears the epiphysis of distal end of radus forms tow thirds the diaphysis.
-The trochlea and capitulum unite together at 14 years.
- The trochlea and capitulum unite with the shaft of humerus at 15 years .
The lateral epicondyle unites with the shaft of humerus at 16 years.
-The medial epicondyle unites with the shaft of humerus at 17years.
-The head of the humerus unites with the shaft at 20 years .
-The upper end of ulna fuses with the shaft at 16 years.
-The upper end of radius fuses with the shaft at 17 years.
-The distal ends of both radius and ulna fuse at 20years.
-The distal ends of metacarpals fuse at 18 years.
B- Lower limb:
-The lesser trochanter of femur unites with the shaft at 16 years.
-The greater trochanter of femur unites with the shaft at 17 years.
- The head of femur unites with the shaft at 18 years.
- The distal end of femur unites with the shaft at 21 years.
- The distal end of tibia and fibula unite at 18 years.
- The upper ends of tibia and fibula unite at 21 years.
C- Clvicle:
The sterna end of clavicle unites at 23 years.
D- Sternum:
-the body unites with xyphoid process at 40 years.
-the manubrium unites with body at 60 years
E-Hip bone:
- The inferior ramus of pubic bone unites with superior ramus of ischium at 6 years.
-The 3 bones ( Ilium ,ischium and pubis) unite at the acetabulum at puberty.
-The ischialtubersity unites at21 years.
-The iliac crest unites at 23 years.
4- Closure of fontanel:
-Posterior fontanel at birth.
-Anterior fontanel at 18 months.
5- Fusion of sutures:
-The frontal suture fuses completely at 3 years.
-The basiocciput fuses with the basisphenoid at 23 years.
-The sagittal suture starts fusion at 25 years and is complete at 30 years.
-The coronal suture fuse at 40 years.
-The lambdoid suture fuse at 50 years.
6- Modularly cavity of humerus:
-Reaches the anatomical neck at 33 years.
-Reaches the surgical neck at 30 years.
IV. Identification of Race
In Negroid race the skull has specific characters:
-The shape of the skull is elongated (dolycocephaly).
-The alveolar margin of the maxilla is protruded forming a prognathism.
-The hard palate is flat .
-The nasal orfices are wide.
-The frontal suture is persistent and does not fuse.
V. prints
Finger prints
Lip prints
Frontal sinus
palatal rugae
palm prints
Iris pattern
Eye prints
DNA finger print
Sole prints
Voice print
Ear print