Porotic hyperostosis is currently considered to be one of several stress markers available for assessing the health and nutritional status of past human populations. The present study questions one of the basic assumptions underlying its use; that is, that the occurrence of porotic hyperostosis in an individual represents an episode of anemia that was current or had occurred within a relatively short period prior to death. A synthesis of data from a Romano-British site Poundbury Camp, anthropological and clinical studies, and information on bone physiology suggests that lesions of porotic hyperostosis seen in adults are most probably representative of a childhood episode of anemia. Lesions seen in adults are the result of bone changes occurring in the growth period that have not undergone complete remodelling. This viewpoint has implications for future interpretation of data on porotic hyperostosis obtained from skeletal collections.

Porotic hyperostosis is a paleopathologic condition that has intrigued researchers for over a century and a half. It is now generally accepted that anemia, most probably an iron deficiency anemia, is the etiologic factor responsible for lesion production. Although there can be a number of factors involved in the development of iron deficiency anemia, a dietary explanation has often been invoked to explain the occurrence of porotic hyperostosis in past human skeletal populations. In fact, porotic hyperostosis has been referred to as a "nutritional" stress indicator. Traditionally those groups with a higher incidence of porotic hyperostosis have been considered to be less successful in adapting to their environment or more nutritionally disadvantaged than other groups.

The multifactorial aging method has been shown to be a highly reliable method of skeletal aging because it incorporates age information from as many age indicators as are available for each skeleton (Lovejoy et al.; Am. J. Phys. Anthropol. 68:1-14, 1985). The present study was a blind test to assess its accuracy on a skeletal sample composed of 55 individuals with verified death certificates (Grant Collection, University of Toronto). Three authors (C.O.L., M.E.B., and K.F.R.), with no access to the death certificate ages, independently seriated and aged the sample using three to four criteria: auricular surface, pubic symphysis, and radiographs of the proximal femur and clavicle. Summary ages were then calculated for each individual in the sample. The authors' independent summary age estimates showed strong correlations with one another (r = 0.84-0.89). Multifactorial age estimates correlated better with real age than did those from any single indicator used. The mean error (averaging 8.7 years) for summary age was at least 1 year less than that for any single indicator. Average bias ranged from -0.7 (underage) to 1.4 (overage) years. These results indicate that utilization of several age indicators, weighted according to their reliability, helps control for variation in the changes that occur with age in any single morphological indicator. This method may therefore be considered one of the most accurate available for the determination of skeletal age-at-death, particularly for paleodemographic analysis.

The etiology of skull lesions known as porotic hyperostosis has long been a matter for speculation. The most widely accepted theory at present suggests that an anemia, either acquired or genetic, is responsible for lesion development. However, acceptance of this theory is not universal and the nature of the relationship between orbital and vault lesions remains a controversial issue. This paper provides a much broader field of supportive evidence on which to base the anemia theory. This involves a synthesis of information from the clinical and anthropological literature as well as new data from two skeletal collections: Poundbury Camp, a Romano-British series, and the Hodgson collection, a 19th century East Asian series. A comparison is made between clinical and anthropological data at the macroscopic, microscopic, radiographic, and demographic levels of analysis. This approach reveals the similarities in expression between clinically diagnosed anemias and porotic hyperostosis.

The exact nature of the relationship between orbital and skull vault lesions of porotic hyperostosis has remained a controversial issue among anthropologists. Many researchers believe that lesions in both areas are related and have a common etiology; others remain unconvinced of any relationship and prefer to consider orbital and vault lesions as separate conditions with their own etiology. This paper explores the issue by comparing data on microscopic, macroscopic, radiographic, and demographic aspects of orbital and vault lesions from both clinical and anthropological studies. The results of these comparisons support the views that there is a relationship between lesions on both areas and that they share a common etiology.