There are characteristic anthropological and biological factors that can be used for identification of an individual. Bone being resistant to putrefaction and damage caused by animals can be used for identification and can help in estimation of age, gender and race. Significant data for human proof of identity procedures have been provided by anthropometric researches of skeletal structure.

Sex identification is very important compared with age and race identification as it excludes almost half of the population. The main anthropological methods used for gender identification are either directly measuring the skeletal remains or by imaging techniques. The major problems to obtaining intact bones are; trauma, decomposition, and disappearance for different causes.  The costal cartilages are bars of hyaline cartilage. These are present at the anterior end of ribs and it provides elasticity to the walls of thorax [1]. 

Costal cartilage has been a subject of great interest in medical literature. Different studies are carried out in past and their results shows presence of sexual dimorphism. These differences were first reported by FISCHER [2] ^and later on by ELKELES, A. [3]and Sanders, C. F. [4].

The radiographic appearance of calcification is broadly divided into three categories- peripheral, central, mixed. Rao, N. G. and Pai, L. M. [5] further divided peripheral into two categories. Verma, G. L. et al. [6] divided central into three sub groups. All earlier studies show peripheral type of calcification pattern tends to occur in males, whereas central type of calcification in females is more predominant. These observations provide an evidence of presence of sexual dimorphism in lower costal cartilage. This knowledge can be useful in forensic cases and medicolegal cases.

Benefits Of Sex Determination by Chest Radiographs

• Study of costal cartilage is easy and simple

•  One of the advantages is it is inexpensive method as compare to CT, MRI

• No need of specific expertise like pathologist to report the opinion

• It can be use as a preliminary test for the subjects requesting sex identification after attaining of puberty

This Method Is Beneficial in Following Cases

• In medicolegal case examination in hospitals

• Where thoracic cage is only present for examination

• For the individuals who have inter sex related issues

• For mass disaster cases

• A putrefied dead body

Although the role of costal cartilage for sex determination has been studied earlier, there are limitations from population to population as majorities of studies are conducted on very small populations. This method is very effective when skull and pelvis are absent. The study with larger population size is needed to draw significant conclusion.

1. Gray H. "Gray’s anatomy." 20th ed., 1918.

2. Vastine J.H. et al. "Genetic influence on osseous development with particular reference to the deposition of calcium in the costal cartilages." Am J Roentgenol Radium Ther, vol. 59, no. 2, 1948, pp. 213–221.

3. Elkeles A. "Sex differences in the calcification of the costal cartilages." J Am Geriatr Soc, vol. 14, no. 5, 1966, pp. 456–462.

4. Sanders C.F. "Sexing by costal cartilage calcification." Br J Radiol, vol. 39, no. 459, 1966, pp. 233.

5. Rao N.G., Pai L.M. "Costal cartilage calcification pattern—a clue for establishing sex identity." Forensic Sci Int, vol. 38, no. 3–4, 1988, pp. 193–202.

6. Verma G.L. et al. "Sex determination by costal cartilage calcification." Indian J Radiol Imaging, vol. 34, no. 1, 1980, pp. 22–25.