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                            DEPARTMENT OF ANATOMICAL SCIENCES

 

                                       AN321  - FORENSIC OSTEOLOGY

 

                         AGE DETERMINATION FROM THE SKELETON

 

                                                            Laboratory

 

 

 

OBJECTIVES

 

Once this practical class has been completed, the student should be capable of:-

 

 

            1.         Identifying and describing the morphological indicators of immaturity

                        in a skeleton.

 

            2.         Determining the approximate gestational age of a foetal skeleton from

                        the diaphysial length of the long bones.

 

            3.         Determining the approximate age of a juvenile skeleton from the

                        diaphysial length of the long bones.

 

            4.         Determining the approximate age of a juvenile cranium by the state of

                        dental eruption.

 

            5.         Determining the approximate age of a juvenile from a radiograph of the

                        hand and wrist.

 

            6.         Determining the approximate age of an adult skeleton by the pubic

                        symphysial methods of Suchey-Brooks or MeKern & Stewart.

 

            7.         Determining the age range of an individual by the Iscan Rib Phase

                        Method.

 

            8.         Determining the approximate age of an adult skeleton by the state of

                        attrition of the molar teeth.

 

            9.         Identifying evidence of arthritis in the bones of the vertebral column

                        and limbs.

 

            10.       Determining the approximate age of an adult skeleton by the state of

                        ossification of the thyroid cartilage.


TEACHING MATERIALS

 

 

HANDOUTS

 

            Laboratory class notes.

            Diagrams of age changes in the pubic symphysial surface

            Diagram of age changes in the sternal rib ends

            Diagram of the ages of dental eruption

            Tables and figures of foetal diaphysial bone lengths relative to age

            Femoral Length growth chart

            Diagram of Dental attrition relative to age (Brothwell 1981)

           

 

 

SPECIMENS and DEMONSTRATIONS

 

            Radiograph of a foetal skeleton for age estimation

            Isolated juvenile long bones

            Demonstration sets of deciduous and permanent dentitions

            Hand and wrist radiograph of a juvenile

            Isolated maxillae and mandibles with molar teeth

            The Suchey-Brooks teaching set of pubic symphysial casts for male age             determination

            The Suchey-Brooks male standard pubic symphysial casts for age estimation

            The McKern & Stewart Male Pubic Symphysial Standards for age estimation

            The Iscan Rib Age Determination Standard Casts

            Unknown pubic symphyses and rib ends for age estimation

            Disarticulated juvenile skeleton

            Sample bones with arthritic changes

            Ossified thyroid cartilage

 

 

 

EQUIPMENT

 

            Radiograph light-box

            Osteometric board

            Sliding callipers

            Calculator

            Greulich Pyle Radiographic Atlas of skeletal development of the hand and

            wrist


EXERCISE 1.

 

THE JUVENILE SKELETON

 

Demonstrations of Juvenile Characteristics of the Skeleton

 

 

 

EXAMINE the juvenile skeletal demonstrations listed below and observe the morphological features of immaturity.

 

 

Demonstration 1.                   - foetal & neonatal material

 

            SPECIMENS:              . cleared foetus

                                                . articulated neonatal skeleton

 

            NOTE the presence of primary ossification centers and lack of secondary          ossification centers.

 

 

 

 

Demonstration 2.                   - juvenile skeletal material

 

            SPECIMENS:              . a disarticulated juvenile skeleton

                                                . 2 articulated juvenile skeletons

                                                . isolated juvenile bones showing absent, and fusing

                                                  secondary centers and growth plates

                                                . juvenile cranium with patent basicranial growth plate

 

 

            NOTE on the juvenile crania:

 

                        closed fontanelles

                        fusion of the interfrontal suture

                        fusion of the symphysis menti

                        varying development and eruption of the teeth

                        development of the tympanic plate

                        state of fusion of the occipital bone

                        state of fusion of the basicranial synchondrosis


EXERCISE 1. (cont.)

 

THE JUVENILE SKELETON

 

            NOTE on the juvenile postcranial material:

 

                        state of fusion of the vertebral arches

                        state of development of the sacrum

                        state of development of the sternum

                        state of development of the hip bone

                        ossification of the long bone epiphyses

                        ossification of the patella (knee-cap)

                        ossification status of the carpus and tarsus

 

 

 

Demonstration 3.                   - the juvenile dentition

 

            SPECIMENS:              . a demonstration set illustrating the primary dentition

                                                . juvenile crania with mixed dentitions

                                                . a demonstration set illustrating the secondary dentition

 

            NOTE:                         . the location and state of development of unerupted teeth

                                                . the sequence of eruption of the permanent teeth


EXERCISE 2.

 

FOETAL AGE ESTIMATION FROM LONG BONE LENGTHS

 

 

Case History (A733):

 

Police were called into a Papua New Guinean village when it was noticed that a rag bundle that had been dug up from under a village house by one of the local dogs appeared to contain the remains of a human baby. A teenage girl living in the house admitted that she had been recently pregnant but claimed that she had miscarried at 16 weeks and had delivered a stillborn child. She had buried the dead child under the house without telling anyone.

 

The local police suspected infanticide of a term pregnancy and requested that a post-mortem and foetal age estimation be carried out to try to confirm their suspicions.

 

Laboratory inspection revealed that the remains were skeletonized and recognisable among them were remnants of a human cranium, mandible and limb long bones.

 

The major limb long bones have been arranged in approximate anatomical position and then radiographed.

 

 

 

 

 

 

You are asked

 

            a)         to measure the lengths of the appropriate limb long bones in the

                        radiograph and record in the following result sheet

 

            b)         to calculate and record the foetal age using the regression formulae

                        extracted from Scheer et al 1980. (attached)

 

            c)         to compare the above results with those obtained by plotting the femoral

                        length on the graph in Fig 110 (attached) which is from the publication

                        of Stewart (1968)

 

 

 

What would be your response to the police?


EXERCISE 2 (cont.)

 

                                                Result Sheet:

 

ENTER THE RESULTS of your bone measurements (in mm) into the table below:

 

                        ----------------------------------------------------------------

                                    Bone               :           Bone length (mm)

                        ----------------------------------------------------------------

                                    Femur             :

                        ----------------------------------------------------------------

                                    Tibia                :

                        ----------------------------------------------------------------

                                    Humerus         :

                        ----------------------------------------------------------------

                                    Radius                        :

                        ----------------------------------------------------------------

                                    Ulna                :

                        -----------------------------------------------------------------

 

 

 

Now using the following formulae from the tables supplied (Scheuer et al 1980) CALCULATE the approximate foetal gestational age and ENTER into the following table.

 

                           Formula       :           Estimated Foetal        :   se

                                                :                 Age                       :

                        -----------------------------------------------------------------

                            1.01             :                                               :

                        -----------------------------------------------------------------

                            1.02             :                                               :

                        -----------------------------------------------------------------

                            1.03             :                                               :

                        -----------------------------------------------------------------

                            1.04             :                                               :

                        -----------------------------------------------------------------

                            1.06             :                                               :

                        -----------------------------------------------------------------

                            1.08             :                                               :

                        -----------------------------------------------------------------

                            1.10             :                                               :

                        -----------------------------------------------------------------

                            1.12             :                                               :

                        -----------------------------------------------------------------


EXERCISE 3.

 

JUVENILE AGE ESTIMATION

 

a)         FROM LONG BONE LENGTH.

 

            MEASURE AND RECORD the maximum diaphysial (shaft) length of the juvenile

            femur JU13.

 

                                    Femur Diaphysial Length                       ............................mm

 

 

            ESTIMATE the approximate age of JU13 using the femoral growth curve provided.

 

                                    Estimated age                                       ............................yrs

 

 

 

 

 

b)         FROM THE STATE OF DENTAL ERUPTION.

 

 

            EXAMINE the mixed dentition in the juvenile cranium provided and from

            the dental eruption chart provided (from Brothwell 1981) ESTIMATE the

            approximate age.

 

 

            Specimen ID NO.......................                      Estimated Age  .............

 

 

 

 

 

c)         FROM THE RADIOGRAPHIC APPEARANCE OF THE HAND AND

            WRIST

 

            The charred remains of a male child were recovered from the ruins of a

            house fire in which two adults also died. The following radiograph of the

            hand and wrist was obtained from the juvenile corpse.

 

            Compare this radiograph with the radiographic standards in the Greulich

            Pyle Atlas and provide an estimate of the age of the child.

 

 

            Radiograph ID Number.................                   Estimated Age  .............

 

 

EXERCISE 4.

 

THE SUCHEY-BROOKS PUBIC SYMPHYSIAL AGEING METHOD

 

a)         Familiarisation with the Technique

 

 

 

 

EXAMINE the set of six standard male pubic symphysial casts that illustrate the six phases of symphysial metamorphosis (Katz & Suchey 1986) and familiarise yourself with the individual phase descriptions in the attached list.

 

 

 

 

 

b)         Application of the Technique

 

 

 

EXAMINE the unknown male pubic symphysis provided, compare with the Suchey Brooks male standards and determine the Suchey-Brooks phase and the associated age.

 

 

 

            Specimen ID No: ......................

 

            Phase................................. Age?..................................


EXERCISE 5.

 

THE MCKERN & STEWART PUBIC SYMPHYSIAL AGEING METHOD

 

a)         Familiarisation with the Technique

 

 

READ the attached pages from McKern (1970) that describe the three components of the pubic symphysial surface that are assessed individually when applying the McKern & Stewart (1957) ageing technique.

 

EXAMINE the set of standard male pubic symphysial casts that illustrate the age changes in the three components and FAMILIARISE yourself with their appearance.

 

 

b)         Application of the Technique

 

EXAMINE the unknown male pubic symphysis provided (PS1), compare with the standards and determine the STAGE (1-5) for each component. ENTER each stage into the table below.

 

 

                                                            STAGE

 

                        Component   I              ..............

 

                        Component  II              ..............

 

                        Component III              ..............

 

                                                ______________

           

                                    Total Score

                                                ______________

 

 

 

            ESTIMATED AGE      ....................................

 

 

 

 

NOTE the upper age limit for application of this technique. Why do you think this is so?


EXERCISE 6.

 

AGE ESTIMATION USING THE ISCAN RIB PHASE METHOD

 

 

 

Examine the set of demonstration casts obtained from the sternal ends of the ribs and familiarise yourself with the 9 standard phase descriptions  and appearances.

Note that because of sexual dimorphism, a different set of casts must be used for age determination in each sex (M0-M8;F0-F8).

 

 

 

 

 

 

Now estimate the age of the half skeleton sets provided using this method.

 

 

 

Skeleton ID No   ...............

 

                        Sex ...........                  Rib Phase         ...............

 

                        Estimated Age Range                            ...............

 

 

 

 

Skeleton ID No   ...............

 

                        Sex ...........                  Rib Phase         ...............

 

                        Estimated Age Range                            ...............

 


EXERCISE 7.

 

AGE ESTIMATION FROM THE STATE OF DENTAL ATTRITION

 

 

EXAMINE the demonstration sets of isolated upper and lower jaws and using the dental attrition chart of Brothwell (1981), estimate the approximate age of each specimen.

 

 

                                    --------------------------------------------------------

                                    Specimen ID               :           Estimated age

                                    --------------------------------------------------------

                                                                        :

                                    --------------------------------------------------------

                                                                        :

                                    --------------------------------------------------------

                                                                        :

                                    --------------------------------------------------------

                                                                        :

                                    --------------------------------------------------------

                                                                        :

                                    --------------------------------------------------------

 

 

 

 

 

 

 

 

EXERCISE 8.

 

ARTHRITIC CHANGES IN THE SKELETON

 

 

EXAMINE the demonstrations of arthritic changes in the vertebrae and long bones.


EXERCISE 9.

 

AGE ESTIMATION FROM THE OSSIFIED THYROID CARTILAGE

 

 

EXAMINE the specimen of an ossified thyroid cartilage and estimate its approximate age from the chart attached.

 

 

 

                                              ESTIMATED AGE................

 

 

 

 

 

REFERENCES

 

Brothwell DR 1981 Digging up Bones. 3rd edition, Oxford University Press.

Gilbert BM & TW McKern 1973 "A Method for Ageing the Female Os Pubis." AJPA 38:31-38

Iscan MY 1989 Age Markers in the Human Skeleton. CC Thomas Springfield

Katz D & JM Suchey 1986 "Age determination of the male os pubis." AJPA 69:427-435

McKern TW & TD Stewart 1957 "Skeletal Age Changes in Young American Males, analysed from the standpoint of identification." Headqu QM Res and Dev Command, Tech Rep EP-45 Natick, MA

McKern TW 1970 "Estimation of Skeletal Age: From Puberty to about 30 Years of Age." in Personal Identification in Mass Disasters. TD Stewart (Ed). National Museum of Natural History, Smithsonian Institute, Washington DC

Scheuer JL, Musgrave JH & SP Evans 1980 "The Estimation of Late Foetal and Perinatal Age from Limb Bone Length by Linear and Logarithmic Regression." Annals Hum Biol 7 (3):257-265

Stewart TD 1968 Identification by Skeletal Structures. Chapter 11 (pages 123-54) in Gradwohl's Legal Medicine, 2nd edition, John Wright & Sons Publishers.