The paleoepidemiology of Sacral Spina Bifida Occulta in population samples from the Dakhleh Oasis, Egypt.

OBJECTIVE: To document sacral spina bifida occulta (SSB0) prevalence in a population sample from the Dakhleh Oasis, Egypt, and address methodological issues in recording and quantifying SSBO variations. MATERIALS: 442 adult sacra from two temporally disjunct samples from the same deme traversing the 3rd intermediate (TIP) and the Roman Periods. METHODS: Sacra were scored for SSBO, excluding the sacral hiatus. Risk of SSBO was calculated with the common odds ratio and statistical significance by X2. Data were compared to other archaeological SSBO data. RESULTS: SSBO was present in 15.6% of the sample with a slight, but not significant, temporal increase (TIP to Roman Period) in males, and a significant age-correlated increase in both sexes. Most open sacra occurred in young adults. CONCLUSIONS: Data support that SSBO can be considered as a morphogenetic variant. Dakhleh data fall within the prevalence range for most populations, however inter-population comparisons are complicated by methodological inconsistencies. SIGNIFICANCE: SSBO can be used in paleogenetic research. LIMITATIONS: Methodological differences in scoring SSBO prevent effective comparative study. SUGGESTED FUTURE RESEARCH: Future studies require more rigorous and standardized scoring methods. aDNA may be used to corroborate the morphogenetic value of SSBO and determine its clinical significance.