Porotic Hyperostosis

From bonepath

Porotic hyperostosis is the expansion of the diploë and thinned outer table of bones of the vault, viz. parietals (Angel 1966, Schultz 2001). Radiographically, this appears as a skull with its “hair-on-end” (Stuart-Macadam 1985: 391), due to the hypertrophy of diploë. Such porous lesions are present in anywhere from 0.70% (Carlson et al. 1974) to around 30% of skeletal populations (Angel 1966). Across age groups, porotic hyperostosis frequency peaks during childhood and adolescence, thereafter generally decreasing with age (Stuart Macadam 1985, Walker et al. 2009).

As with cribra orbitalia, there is a tendency in the anthropological literature to attribute porotic hyperostosis to some form of iron-deficiency anemia, dietary or hereditary (i.e. Stuart-Macadam 1985). However, such diploic hypertrophy and porosity of the outer table of the vault can also result from scurvy (vitamin C deficiency), rickets (vitamin D deficiency), inflammation of the scalp or vault periosteum, trauma, and osteomyelitis (Schultz 2001, Lagia et al. 2007). Walker and colleagues (2009) further argue that, at least in archaeological populations for whom hereditary anemia would not have been a major issue, porotic hyperostosis is probably resultant of megaloblastic anemia, which in turn resulted from dietary vitamin B6 and B9 deficiency. Thus, porotic hyperostosis could indicate varied nutritional stress, trauma, infection, or hereditary anemia (e.g. thalassemia or sicklemia). The rest of the skeleton may or may not be affected as well; sometimes, porotic hyperostosis of the vault may be associated with similar lesions of the postcranial skeleton, or with growth stunting (Lagia et al. 2007).

References

Angel JL. 1966. Porotic hyperostosis, anemias, malarias, and marshes in the prehistoric Eastern Mediterranean. Science 153:760-3.

Carlson DS, Armelagos GJ, Van Gerven DP. 1974. Factors influencing the etiology of cribra orbitalia in prehistoric Nubia. Journal of Human Evolution 3:405-10.

Lagia A, Eliopoulos C, Manolis S. 2007. Thalassemia: macroscopic and radiological study of a case. International Journal of Osteoarchaeology 17:269-85.

Schultz M. 2001. Paleohistopathology of bone: a new approach to the study of ancient diseases. American Journal of Physical Anthropology Suppl 33: 106-47.

Stuart-Macadam P. 1985. Porotic hyperostosis: representative of a childhood condition. American Journal of Physical Anthropology 66:391-8.

Walker PL, Bathurst RR, Richman R, Gjerdrum T, Andrushko VA. 2009. The causes of porotic hyperostosis and cribra orbitalia: a reappraisal of the iron-deficiency-anemia hypothesis. American Journal of Physical Anthropology 139:109-25.