In this study we have combined both biological and cultural data in the investigation of resorptive pathology in Woodland and Mississippian skeletal series from west-central Illinois. Information concerning the types of lesions and their distribution confirms the presence of a previously unknown disease in Mississippian populations. Adults and adolescents from Yokem and Schild Mississippian components clearly display cystic vertebral pathology, which in association with other peripheral osseous lesions distinguishes them from earlier groups. This idea is supported indirectly by evidence from both infants and children of the Schild sample