Minimally Invasive Surgical Treatment for Vertebral Artery Compression in a Patient with One-Sided Ponticulus Posticus and Ponticulus Lateralis.

Background: Kimmerle anomaly is characterized by ossification of the posterior atlanto-occipital membrane with formation of a complete or incomplete bony ridge in the area of the groove for the vertebral artery (VA) (ponticulus posticus [PP]). In some cases, the bony ridge may also be formed at the level of the VA emerging from the transverse process of the С1 vertebra (ponticulus lateralis [PL]). Simultaneous 1-sided formation of PL and PP is very rare.