The Decreasing Prevalence of the Arcuate Foramen.

Background: The arcuate foramen (AF), or ponticulus posticus, is an anatomic variant of the first cervical vertebra that consists of a complete or partial osseous bridge over the groove for the vertebral artery and extends from the posterior aspect of the superior articular facet to the superior lateral border of the posterior arch. The AF has been associated with clinical symptoms, such as headache, migraine, neck pain, shoulder pain, arm pain, and vertebral artery dissection. We aimed to test whether the prevalence of the AF has decreased in the modern human population over the past centuries as a result of reduction in inbreeding and endogamy.

Methods: Possible reduction in the prevalence of the AF was assessed by comparing a 17th century rural sample (n = 108) with a 20th century modern urban sample (n = 192).

Results: When comparing the 17th and the 20th century samples, we found a statistically significant (P = 0.003) reduction of 14.5% (95% confidence interval 4.5-24.5) in the prevalence of the AF.

Conclusions: Prevalence of the AF has been decreasing over the past centuries.