Determination of Sex by Calcification Pattern of Costal Cartilages in Indian Population

The aim of our study was to evaluate radiologically the differences between males and females based on the patterns of calcification of costal cartilages. Posteroanterior view of chest radiograph of 1000 patients were evaluated for patterns of calcification and analyzed statistically. Four distinct patterns of calcification i.e. diffuse, marginal, marginal bracket and central type were observed. The incidence of calcification increased with advancement of age especially beyond 30 years.

Earliest appearance of calcification of costal cartilage was seen at 15 years in males and 17 years in females. The males predominantly showed marginal calcification with a predictive value of 96.6% whereas females showed central type of calcification with a predictive value of 97.6%. These observations provide an evidence that a definite sexual dimorphism is present in the calcification pattern of the lower costal cartilages and this knowledge can be utilized in medicolegal cases where only thoracic part of the body is available to forensic expert for establishing sex.