Skeltal Remains

7/31/2019 Skeltal Remains

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Skeletal remains

Skeletal poses a typical and classical problem inforensic medicine to identify. Skeletal remains maybe whole but usually they are incomplete.

Many techniques are employed ranging fromanatomy to radiology and archeology to dentistry toidentify intact or decomposed bodies.

Recognition is usually easy by shape, texture andespecially weight. Bones made up by plastic are lightweight.



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Skeletal remains

Bones are important because they can remain intact forcenturies like hairs. There are two major categories.

1. Allotting the bones to general categories based onspecies, race, stature and date.

2. Comparative studies: Where the date of bones ismatched against ante mortem data derived from

those people who might be potential victim.



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General categories of skeletal

remains

Objectives:

1. Are they bones?

2. Are they human origin?

3. What is the sex?4. What is the stature?

5. What is the race?

6.

What is the age?7. How long they have been dead or concealed?

8. What was the cause of death?



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Are the remains actual bones?

This is not a factitious question.Many times people /police bringbones made up of plastic, fiber glass

which they thought as bones.

The problem is more complicatedwhen these are mixes with actualbones usually of animal origin.



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Are the bones of human origin

Deciding of human origin is usually easy.

Small slender bones should be excluded e.g. hen, duck and turkey thighbones cannot be mistaken as human metatarsal bones.

Small bones poses a problem as they are like human digits. Specialproblem in differentiating bones of bear paw from human due to closeresemblance.

Fragments or incomplete are difficult to identify.

If ends of long bones are present then it is easy to identify.

Cylindrical segments of central shaft is difficult to identify.

Burned bones also poses great difficulty added to which is heat shrinkageand /or distortion.



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Histological examination

• Species differences to exclude human

origin at least.

• Herversion architecture is difficult to

identify in many animals.



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Serological investigation

When the bones are too small fragments thenserological tests should be applied. Species specificproteins must be extracted from the bones into solutionthen they are tested against the specific antisera

prepared by immunizing animals (Usually rabbits)against a range of animal proteins usually derived fromblood.

The test is essentially seeking plasma concentrationwithin the bone.

Disadvantage is that the proteins must be presentin bones. Proteins are lost in burned or cremated bonesand in those which has been buried for longer periods of time (A negative result is usually found after 10 years).



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Sex determination

Skull. Pelvis. Femur. Humerus. Sternum:

Females: Length of manubrium may be equal or exceeds half of the body.Males: Manubrium is less than half of its total length.

The accuracy range is somewhat around 80%

*(Some authorities noted that this is not a specific difference and in females it is 52:100 while in males it is 49:100, a narrow negligible margin!)



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Sex determination

Male Female

Manubrium L: 51.7(41-73) 48.4(39-61)

Body length: 95.4(74-122) 78.6(59-95)

Combined length: 147(131-180) 127(107-140)



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Scapula

It is more important in age determination.

Sex: Vertical diameter of glenoid cavity inmales 36 mm and less than 36 mm in

females. Scapular height in males is 157mm and in females less than 144 mm.



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Estimation of stature

It can be directly measured if whole skeleton is availableand if correctly assembled. Allowance should be givenfor loss of cartilages in the joints and especiallyintravertebral discs.

Accuracy is not great in intact bodies. Length increasesby 2.5 cm as compared to live height due to flaccidity.

Thickness of soft tissues of scalp and heel should beadded.

4-8 cm on both sides should be kept in mind.



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Estimation of stature

If incomplete skeletal remains are available,then calculations to be made on the basis of oneor more bones. Reliability varies from bone tobone and the most accurate one is femur.

For example:

Male White: 63.05+131(Femur+Fibula)Male negro: 67.77+1.20(Femur +Fibula)

[3.63 plus minus on both]



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Estimation of age from skeletalstructure

It is more important than the statureand almost equally important as sex.

Greater personal age gives less

accurate results.



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Foetal and young adults

It is better to estimate age from intact body thanfrom bones as these are easily and usuallydispersed, lost and destroyed as compared torobust bones of adults.

Major age indices are ossification centers butthese are rarely available within few weeks.

The bones have to be examined with cartilagesattached with.

Radiology provides more impressive results thanthe visual inspection.

Biological variations changes total results from theprinted tables, so much more experience isneeded.



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Skeletal age in child and youngadults

• Appearance of ossification centers complete around 5years. After this fusion of epiphysis acts as a calendar upto 25 years. Medial end of clavicle is usually the last tofuse.

• Maturity does not follow with calendar age. Sexual,racial;, nutritional and other biological variations arepresent.

• Females are almost always advance of males andmaturity tends to be accelerated in hotter climates butlate may be tempted by nutritional factors.



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Cont:

• There is marked range of closure dates in

epiphysis and years suggested are merelythe mid.

• Union is a process and not an event. Itmay be quite different radiologically fromgross inspection. It may also be slow incompletion e.g. medial end of clavicle is

last to fuse and it may fuse completelyfrom 18-31 years.



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Eruption of third molar tooth and fusion of last

epiphysis completely in the middle of thirddecade. No major event occurs after 25 years so it is

most difficult to estimate accurately.

Most important marker after 25 years are: Pubic sympyhsis: Opposing faces of the two pubicbones have specific changes and indicate bettertowards the age.

Sternal rib pattern: Costochondrial junction.

(i) Calcification in first costal cartilage does not occur below11 years. (ii). After 16 years male calcified much more quickly until

66 years.



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Cont:

Skull sutures

Fusion of skull sutures as an index of agehas had a chequered history , beginningfrom first century AD. It is now generally

discarded.



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Main racial groups are:

1. Caucasians.

2. Negroids.3. Mongoloids.

All others are derived from these andindistinguishable.

Skull offers the best determinant for race. Race can be determined in 90-95% cases.



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Cont:

Teeth: Most important in mongoloid race. Upperincisors are of ‘Shovel shaped ’, posteriorly concaved andmay be grooved on the rear surface.

Japanese 93%Chinese 85%

Eskimos 68%

Negroids 15%

Caucasians Almost absent



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Cont:

Dolicocephalic: Long headed in Negroids.

Brachycephalic: Broad headed in mongoloids.

Whole range in Caucasoid (Mesaticephalic).



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Cont:

Orbit: It is lower and wide in Negroids, higher and round inmongoloids.

Nasal aperture: Wide and prognathism of lower jaw is relatively marked in Negroids.

Pelvis: Specialized measurements are required to differentiatebetween Caucasians and Negroids pelvis.

Femur: \long bones especially femur is important todifferentiate between Negroids and Caucasian races. It is straightin Negros, anteroposterior bowing is less.

Radius and tibia are longer in Negroids, and femur in females ismore bent interiorly (more attractive!)



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Personal identification

• Any idiosyncratic features which may give personalidentity. This is just matching up of the featurespreviously known.

• Anatomically shapes that can be matched by radiology,measurements/other means e.g. frontal sinus,craniometry, radiological bone architecture.

• Discrete abnormalities e.g. healing fractures, metalprosthesis or congenital defects.

• Excellent is the dental radiographs and records to matchwith.

• Lateral view of skull to match the measurements andespecially intracranial diameters and profile of pituitaryfossa.



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Frontal sinus identification

It was first suggested in 1921 and late ron adopted in 1935.

Sinuses are well protected from almost all traumas except inextreme damage.

Particularly useful in mutilated and burnt bodies.

In 1935 it was identified by Poole that no two persons (not even theidentical twins) have the same profile of these air spaces.

Appears in 2nd year of life and mature in size in first 2 decades.

Absent in 5% and present unilateral in 1%.



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For comparison ante mortem antro-posteriorradiograph must be available.

The post mortem radiograph must be taken inthe same position and with same projection tobe used for superimposition.

Forehead nose position is suggested with tube

axis positioned at supra orbital margin.

Scalloped upper margin is used fro comparison.

Cont:



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Other radiographic methods

Hand and wrist films.

First rib and clavicle.

Craniometric method.

When ante mortem x-rays are availableespecially of skull, throat, hip or shoulder theseare of great help.



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Dating

If skeletal remains are of considerableantiquity, no further investigations are requiredeven if the death was criminal, the culprit may long since have dead. It is around 70 years(perfect murder)



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Physical appearance

Recent: Soft tissue attached with presence of cartilage.In well protected bodies remains in good condition formany years.

Density and feel:Slightly greasy to touch in recentbones, may be in old bones of decades. Recent bones

are heavier than old bones due to increased density.

On sawing: Hard to cut and cut ends are uniform

through the whole thickness especially shaft of long bones.



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Physical appearance

On vigorous cutting, heat generated will givesmell of organic material burning.

In old bones collagen stroma will be lost, they become lighter and can be cut easily.

Old bones also shows a sandwich effect.



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Physical Test

It emits fluorescence in UV light whenseen in dark back ground. It will mittsilvery blue tint right across the wholesection in recent bones. As the bone ages,outer rim will give diminished tint and it

confines more towards center.



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Other Physical Test

Density.

Specific gravity.

Ultrasound conditions. Thermal behavior.

Photo superimposition technique.

Reconstruction of the facial appearancefrom skull.



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Identification

Stature Height



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Identification

Bones found in soil.



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Identification

UV light



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Human skull



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UV light



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Forensic problem



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Burned bones.



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Herversion canals.



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Position of orbit Asian and Caucasian.



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Cremation chamber.

R i f b



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Reconstruction from bony parts.

B f



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Bony fragments.



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Skull parts.



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Unilateral frontal

sinus.

R t ti



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Reconstruction

R t ti



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Reconstruction

R i



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Reconstruction



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Reconstruction from skull and other few bones(Archeological)

Frontal sin s



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Frontal sinus



Ossification center



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Ossification center

O ifi i



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Ossification center

hands

O ifi i



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Ossification centers

elbow

E i h i



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Epiphysis



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Caucasian

skull

M l id k ll



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Mongoloid skull



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Right Mongoloid left Negroids



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Mongoloid



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Mongoloid



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Negroid

Faces of different



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Faces of different

races

Pubic



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Pubic



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Mass disastor

T tt i id tifi ti



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Tattoos in identification



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Frontal sinus

Pel is



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Pelvis

Pelvis and pelvic



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Pelvis and pelvic

Femur & humerus



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Sex difference in pelvis & pelvic



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Sex difference in pelvis & pelvic

Herversion canals



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Herversion canals

UV bones



UV bones

Skeltal Remains

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