Aside from the supposed armor, very little has been described of the anatomy of "Agustinia". A fibula (lower leg bone) has been recovered that is about long. When compared to the same bone in related dinosaurs, this indicates that "Agustinia" may have been about long. However, the remains are incomplete and do not appear to have many distinctive characteristics which can be used to separate it from other sauropods. With the supposedly distinctive armor discredited, some authors have considered "Agustinia" a "nomen dubium", for being based on remains not adequate to compare with related dinosaurs. The lower half of the tibia was thin when viewed from the front (anteroposterior), indicating that the tibia was thinner than that of titanosaurs such as "Antarctosaurus" or "Saltasaurus". The pedal elements correspond to those of the titanosaurs.