A case of glenoid dysplasia: palaeopathological analyses on a Roman skeleton of Milan

The focus of this presentation is to examine aspects regarding a case of congenital glenoid dysplasia, already present in antiquity, and its possible association with several syndromes. This study also aims to investigate the impact of the condition on the experience of the individual and their daily life in Roman times. The bioarchaeological analysis of skeletal remains (III – V century CE) from the Roman necropolis of the Cattolica in Milan revealed an emblematic case of a young individual, estimated male between 18 and 22 years, with several pathological changes. The skeleton exhibited bilateral glenoid retroversion, agenesis of the lower central incisors, and a peculiar shape of the roots of the lower premolar and molar teeth, as well as enamel hypoplasia on the lower teeth. Remodelled periosteal new bone was also found on the diaphysis of the left tibia, which could be pertinent to a post-traumatic inflammation. Additionally, the individual shows nonmetric features, such as the presence of a 13th thoracic vertebra and bilateral 13th ribs. Glenoid retroversion is usually caused by a congenital malformation and may occur as an isolated primary condition. The differential diagnosis of glenoid dysplasia includes syndromes with multiple anomalies, such as Ehlers-Danlos and Apert, but vitamin deficiencies and obstetric trauma cannot be ruled out. Absence of the cranium does not allow for a more specific diagnosis. Bilateral glenoid dysplasia may have caused shoulder pain, limited range of motion, and joint instability, but in the absence of soft tissues it is not possible to assess these aspects. Each syndrome is associated with posterior shoulder instability, leading to functional disability. Glenoid retroversion has been observed in a few skeletons from European archaeological sites: one from 4th–3rd century BCE, five from the medieval period and three from modern period. This presentation will illustrate a case from Roman Italy, not yet reported in the literature.