The radiological investigation of the ossification stage of the medial clavicular epiphysis represents the crucial tool for assessing whether a living individual has completed the age of 18 years. However, exposure to radiation cannot always be accepted due to legal reasons and radiation-free methods still lack reference data or are not available. Therefore, this study examines the role of pre-existing radiographic material of the clavicles, making it necessary to prospectively validate the established five-stage classification system for evaluating the clavicular ossification process as well as to enlarge the so far very limited pool of available reference data. Accordingly, standard posterior-anterior projection radiographs of 836 sternoclavicular joints prospectively obtained during 418 forensic autopsies (age range 15-30 years) were analyzed. Stage III was first found at ages 16 and 15 (males/females), stage IV at ages 22 and 21 (males/females), and stage V at age 26 in both sexes. The presented results principally corroborate the previous reference data from 2004, suggesting reliability of the five-stage classification system. In conclusion, chest radiographs may still be useful for forensic age diagnostics in living individuals but only in certain cases. In age estimations which can be planned in advance, projection radiography of the clavicle must still be considered obsolete.
