Sex Determination
Skeletal maturation accelerates in females at a greater rate than in males after the third or fourth year of life. However, this difference is not a useful determinant.
Fig. 10. Mature newborn knee showing calcified distal femoral and proximal tibial epiphyses. Reprinted from Brogdon, BG, Forensic radiology (1998) with permission from CRC Press.
Fig. 10. Mature newborn knee showing calcified distal femoral and proximal tibial epiphyses. Reprinted from Brogdon, BG, Forensic radiology (1998) with permission from CRC Press.
Table 1
Percentiles for Age at Appearance (Years-Months) of Selected Ossification Centers
Table 1
Percentiles for Age at Appearance (Years-Months) of Selected Ossification Centers
|
Centers |
Boys Percentile |
Girls Percentile | ||||
|
5th |
50th |
95th |
5th |
50th |
95th | |
|
— |
0-0 |
0-1 |
- |
0-0 |
0-0 | |
|
2. Cuboid |
- |
0-1 |
0-4 |
- |
0-1 |
0-2 |
|
3. Femur, head |
0-1 |
0-4 |
0-8 |
0-0 |
0-4 |
0-7 |
|
4. Cuneiform 3 |
0-1 |
0-6 |
1-7 |
- |
0-3 |
1-3 |
|
5. Toe phalanx 5 M |
- |
1-0 |
3-10 |
- |
0-9 |
2-1 |
|
6. Toe phalanx 1 D |
0-9 |
1-3 |
2-1 |
0-5 |
0-9 |
1-8 |
|
7. Toe phalanx 4 M |
0-5 |
1-3 |
2-11 |
0-5 |
0-11 |
3-0 |
|
8. Toe phalanx 3 M |
0-5 |
1-5 |
4-3 |
3-0 |
1-0 |
2-6 |
|
9. Toe phalanx 3 P |
0-11 |
1-7 |
2-6 |
0-6 |
1-1 |
1-11 |
|
10. Toe phalanx 4 P |
0-11 |
1-8 |
2-8 |
0-7 |
1-3 |
2-1 |
|
11. Toe phalanx 2 P |
1-0 |
1-9 |
2-8 |
0-8 |
1-2 |
2-1 |
|
12. Toe phalanx 2 M |
0-11 |
2-0 |
4-1 |
0-6 |
1-2 |
2-3 |
|
13. Cuneiform 1 |
0-11 |
2-2 |
3-9 |
0-6 |
1-5 |
2-10 |
|
14. Metatarsal 1 |
1-5 |
2-2 |
3-1 |
1-0 |
1-7 |
2-3 |
|
15. Toe phalanx 1 P |
1-5 |
2-4 |
3-4 |
0-11 |
1-7 |
2-6 |
|
16. Toe phalanx 5 P |
1-6 |
2-5 |
3-8 |
1-0 |
1-9 |
2-8 |
|
17. Cuneiform 2 |
1-2 |
2-8 |
4-3 |
0-10 |
1-10 |
3-0 |
|
18. Metatarsal 2 |
1-11 |
2-10 |
4-4 |
1-3 |
2-2 |
3-5 |
|
19. Femur, greater trochanter |
1-11 |
3-0 |
4-4 |
1-0 |
1-10 |
3-0 |
|
20. Navicular foot |
1-1 |
3-0 |
5-5 |
0-9 |
1-11 |
3-7 |
|
21. Fibular, proximal |
1-10 |
3-6 |
5-3 |
1-4 |
2-7 |
3-11 |
|
22. Metatarsal 3 |
2-4 |
3-6 |
5-0 |
1-5 |
2-6 |
3-8 |
|
23. Toe phalanx 5 D |
2-4 |
3-11 |
6-4 |
1-2 |
2-4 |
4-1 |
|
24. Patella |
2-7 |
4-0 |
6-0 |
1-6 |
2-6 |
4-0 |
|
25. Metatarsal 4 |
2-11 |
4-0 |
5-9 |
1-9 |
2-10 |
4-1 |
|
26. Toe phalanx 3 D |
3-0 |
4-4 |
6-2 |
1-4 |
2-9 |
4-1 |
|
27. Metatarsal 5 |
3-1 |
4-4 |
6-4 |
2-1 |
3-3 |
4-11 |
|
28. Toe phalanx 4 D |
2-11 |
4-5 |
6-5 |
1-4 |
2-7 |
4-1 |
|
29. Toe phalanx 2 D |
3-3 |
4-8 |
6-9 |
1-6 |
2-11 |
4-6 |
|
30. Calcaneal apophysis |
5-2 |
7-7 |
9-7 |
3-6 |
5-4 |
7-4 |
|
31. Tibial tubercle |
9-11 |
11-10 |
13-5 |
7-11 |
10-3 |
11-10 |
Note: P, proximal; M, middle; D, distal. Important events at various ages are in bold. Reprinted from ref. 20, with permission from Elsevier.
Note: P, proximal; M, middle; D, distal. Important events at various ages are in bold. Reprinted from ref. 20, with permission from Elsevier.
In general, the male skeleton becomes more robust and heavier with aging and develops more prominent attachments for muscles and tendons. With further aging, there is a tendency for more degenerative hyperostotic changes in the male. Male long bones are approx 110% longer than their female counterparts. The male femoral head is larger. All of these findings are helpful but not definitive in establishing the sex of unidentified remains.
- Fig. 11. Chronological development of the knee. Reprinted from ref. 25 with permission from Charles C. Thomas. Tracings reprinted from ref. 25 with permission from Elsevier.
Other parts of the skeleton are far more helpful than those of the extremities. Bipartite patella, an anatomical variant occurring in approx 2% of the adolescent population, is nine times more common in boys than in girls (27).
In individuals of African ancestry, the tibia is long relative to the femur, but the ratios vary and overlap in US populations, probably due to racial mixing. The femoral shaft is bowed anteriorly in white and Asian populations compared with black populations; however, there is still considerable variability. However, a markedly bowed femur is unlikely to belong to a black decedent (28).
- Fig. 12. Chronological development of the foot and ankle. Reprinted from ref. 26 with permission from Charles C. Thomas. Tracings reprinted from ref. 25 with permission from Elsevier.
Fig. 12. Continued.
Fig. 12. Continued.
Craig (29) developed a method of determining race based on the angle of the intercondylar shelf on the femur that can be used with either skeletal or fleshed remains (Fig. 13). It requires radiography with true lateral positioning of the distal femur. The angle between the roof of the intercondylar notch (or intercondylar shelf) and the long axis of the femoral shaft are measured. Figure 14 shows the bimodal nature of the racial curves, indicating a fairly narrow overlap between the sectioning points. Thus, this may serve as a fairly useful determinant for assigning race or population ancestry.
- Fig. 13. Lateral radiograph of the knee illustrating method of measuring the intercondylar shelf angle. Reprinted from Brogdon, BG, Forensic radiology (1998) with permission from CRC Press.
0.12
o.oo
|
BLACK / \ |
/ \white |
|
/ / |
\ \ degrees |
140 145 150 INTERCONDYLAR SHELF ANGLE
Fig. 14. Graphic representation of racial distribution of intercondylar shelf angles. Courtesy of Michael D Harpen, PhD. Reprinted from Brogdon, BG, Forensic radiology (1998) with permission from CRC Press.
Steinbach and Russell (30) suggested that a measurement of the soft tissue in the heel pad that exceeds 21 mm is a reasonably accurate indication of acromegaly (Fig. 15). However, the fallibility of this diagnostic indicator has been described by Puckett and Seymour (31), who demonstrated a greater-than-"average" heel pad measurement in Blacks, 40% of whom had heel pads exceeding 21 mm compared with only 9% of Caucasians. Local soft-tissue swelling can skew this measurement even further. Hence, heel pad thickness is of doubtful value in the process of determining race or population ancestry in unidentified body parts.
Post a comment