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AN321  - FORENSIC OSTEOLOGY

 

INTRODUCTORY OSTEOMETRY

&

STATURE ESTIMATION

 

Practical

 

 

 

 

 

 

OBJECTIVES

 

 

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

 

 

1.                  Identifying the following pieces of osteometric equipment and describing and

            demonstrating their application:

 

            bone measuring board, spreading callipers, sliding callipers, co-ordinate callipers

            craniophore, Frankfort horizontal stand

 

2.                  Measuring maximum length of the limb long bones using an osteometric board, and

calculating  intra-observer variability.

 

 

3.                  Estimating stature from the limb long bone lengths, after selection of the appropriate

            formulae for race, sex, and age.

 

 

4.                  Identifying, locating and defining the standard osteometric points of the cranium and

            mandible.

 

 

5.                  Defining the Frankfort Horizontal Plane and demonstrating how to align the cranium into

            the plane using The Frankfort Horizontal Stand.

 

 

6.                  Carrying out basic length, breadth, and height measurements of the cranium, and calculating the common cranial indices.

 


TEACHING MATERIALS

 

 

HANDOUTS

 

            Laboratory class notes

            Table and diagram of craniometric points

            Standard tables of stature estimation from various long bone lengths.

 

 

CLASS EQUIPMENT & MATERIALS

 

            osteometric boards, spreading callipers, sliding callipers

            plastic half skeletons

            plastic crania

 

 

DEMONSTRATIONS

 

            Full range of osteometric equipment

 


EXERCISE 1

 

OSTEOMETRIC EQUIPMENT FAMILIARISATION

 

 

Examine and identify the range of osteometric equipment on display in the Laboratory:

 

 

            Bone measuring board              Sliding callipers                         Spreading callipers

 

            Co-ordinate callipers                Palatometer                              Mandibulometer

 

            Tape measure                           Length standards                      Craniophore

 

            Frankfort Horizontal plane stand

 


EXERCISE 2.

 

LONG BONE MEASUREMENT    - lengths, diameters, circumferences

 

 

Using the bone measuring board,, measure and record (in mm) the maximum lengths of the following long bones in  the plastic half skeleton supplied..

 

                        femur                                      ...................mm

 

                        tibia                                         ...................mm

 

                        fibula                                       ...................mm

 

                        humerus                                  ...................mm

 

                        radius                                      ...................mm

 

                        ulna                                         ...................mm

 

 

Using the sliding callipers, measure and record (in mm) the vertical and transverse (horizontal diameters of the femoral and humeral heads on the plastic specimens supplied.

 

                        Femur:     vertical diameter      ......................mm

 

                                          transverse diameter ......................mm

 

                        humerus:  vertical diameter      ......................mm

 

                                          transverse diameter ......................mm

 

 

Using the measuring tape, measure and record (in mm) the midshaft circumference of each of the long bones supplied.

 

                        femur                                      ...................mm

 

                        tibia                                         ...................mm

 

                        fibula                                        ...................mm

 

                        humerus                                  ...................mm

 

                        radius                                      ...................mm

 

                        ulna                                         ...................mm

 


EXERCISE 3.

 

CALCULATION OF STATURE FROM THE LIMB LONG BONES

 

Calculate stature using the appropriate formulae of Trotter & Gleser (1952 & 1958) supplied. Base your calculations on the racial, age, and sex groupings indicated:

 

                                                                        calculated stature            sd

 

            a) European/25yr old /male

 

                        femur                                        ........................cm (+/-........cm)

 

                        tibia                                          ........................cm (+/-........cm)

 

                        fibula                                        ........................cm (+/-........cm)

 

                        combined femur + tibia             ........................cm (+/-........cm)

 

 

            b) European /55yr old /female           calculated stature            sd

 

                        femur                                        ........................cm (+/-........cm)

 

                        tibia                                          ........................cm (+/-........cm)

 

                        fibula                                        ........................cm (+/-........cm)

 

                        combined femur + tibia             ........................cm (+/-........cm)

 

 

            c) Aboriginal/20yr old /female           calculated stature            sd

 

                        femur                                        ........................cm (+/-........cm)

 

                        tibia                                          ........................cm (+/-........cm)

 

                        fibula                                        .......................cm (+/-........cm)

 

                        combined femur + tibia             .......................cm (+/-........cm)

 

 

            d) Aboriginal/75yr old /male              calculated stature            sd

 

                        femur                                        ........................cm (+/-........cm)

 

                        tibia                                          ........................cm (+/-........cm)

 

                        fibula                                        .......................cm (+/-........cm)

 

                        combined femur + tibia             ........................cm (+/-........cm)

EXERCISE 4.

 

INTRODUCTORY CRANIOMETRY

 

Standardised, accurately defined and readily locateable bony landmarks are essential if measurements are to be useful in the description and comparison of bones.

 

a)         Familiarise yourself with the following Craniometric points from the reference list, descriptions and diagrams  supplied (from Moore-Jansen & Jantz 1986 pp46-51). Note in particular:

 

            basion; bregma; ectomolare; endobasion; euryon; glabella; gnathion;

            lambda; nasion; opisthocranion; opisthion; prosthion; zygion

 

b)                  Familiarise yourself with the following Craniometric measurements from the reference list descriptions, and diagrams  supplied (from Moore-Jansen & Jantz 1986 pp52-62). Note in

             particular:

 

                        Cranial Length                                      Measurement  1

 

                        Cranial Breadth                                                Measurement  2

 

                        Bizygomatic Breadth                             Measurement  3

 

                        Basibregmatic Height                            Measurement  4

 

                        Basion-Nasion Length                          Measurement  5

 

                        Basion-Prosthion Length                       Measurement  6

 

                        Maximum Palate Breadth                      Measurement  7

 

                        Maximum Palate Length                        Measurement  8

 

                        Nasion-Prosthion Height                       Measurement  10

 

                        Minimum frontal Breadth                       Measurement  11

 

                        Maximum frontal Breadth                      Measurement  12

 

                        Nasal Breadth                                      Measurement  14

 

                        Frontal Chord                                       Measurement  19

 

                        Mastoid Length                                    Measurement  23

 

 


EXERCISE 5.

 

Now using the spreading, sliding and co-ordinate callipers as appropriate, MEASURE (mm) & RECORD the following measurements on the plastic cranium supplied. Get a friend to hold the cranium while you do your measurements or sit it in one of the foam plastic doughnuts supplied:

 

 

                                                      CRANIUM NO.................

 

 

            Measurement description                 Abbreviation               Measurement (mm)

 

 

            Spreading Calliper:

 

            a) Cranial Length                                  CL                               ................

 

            b) Cranial Breadth                                CB                               ................

 

            c) Basion-Bregmatic Height                  BBH                            ................

 

            d) Basion-Nasion length                        BNL                            ................

 

            e) Basion-Prosthion Length                   BPL                             ................

 

            f) Maximum Bizygomatic Diameter        MxBD                          ................

 

            g) Maximum Supraorbital Breadth         MxSB                          ................

 

            h) Minimum Supraorbital Breadth          MnSB                          ................

 

 

            Sliding Calliper:

 

            i) Nasofrontal Articulation Width           NAW                           ................

 

            j) Nasal Breadth                                   NB                               ................

 

            k) Nasion-Prosthion Height                   NPH                            ................

 

            l) Maximum Palatal Length                    MPL                            ................

 

            m) Maximum Palatal Breadth                MPB                            ................

 

 

            Co-ordinate Calliper:

 

            n) Frontal Chord                                   FC                               ................

 

            o) Frontal Subtense                              FS                                ................

 


EXERCISE 6.

 

INTER-OBSERVER VARIABILITY

 

Swap your cranium with that of a colleague and remeasure:

 

                                                      CRANIUM NO.................

 

            Measurement description                 Abbreviation               Measurement (mm)

 

            Spreading Calliper:

 

            a) Cranial Length                                  CL                               ................

 

            b) Cranial Breadth                                CB                               ................

 

            c) Basion-Bregmatic Height                  BBH                            ................

 

            d) Basion-Nasion length                        BNL                            ................

 

            e) Basion-Prosthion Length                   BPL                             ................

 

            f) Maximum Bizygomatic Diameter        MxBD                          ................

 

            g) Maximum Supraorbital Breadth         MxSB                          ................

 

            h) Minimum Supraorbital Breadth          MnSB                          ................

 

 

            Sliding Calliper:

 

            i) Nasofrontal Articulation Width           NAW                           ................

 

            j) Nasal Breadth                                   NB                               ................

 

            k) Nasion-Prosthion Height                   NPH                            ................

 

            l) Maximum Palatal Length                    MPL                            ................

 

            m) Maximum Palatal Breadth                MPB                            ................

 

 

            Co-ordinate Calliper:

 

            n) Frontal Chord                                   FC                               ................

 

            o) Frontal Subtense                              FS                                ................

 

 

Compare your above measurements with those of your colleague to get an appreciation of inter-observer measurement variability.