An anatomical study of the pterygoalar bar and the pterygoalar foramen

The paper presents anatomical considerations on the pterygoalar bar and the pterygoalar foramen of the human skull. The pterygoalar bar is a bony bridge that stretches between the lateral pterygoid lamina and the greater wing of the sphenoid bone, while the space under this bar is termed the pterygoalar foramen. These structures were noted in 5 out of 70 investigated skulls. The length of the pterygoalar bar ranged from 4 to 8 mm, while the diameter of the pterygoalar foramen ranged from 7 to 11 mm. The presence of the pterygoalar bar is clinically important because it may disturb access to the foramen ovale during anaesthesia of the trigeminal nerve

An atypical position of the foramen ovale

Visual inspection of a dry adult human skull revealed absence of a typical foramen ovale on the left side of the cranial base. The region of the foramen ovale was covered by an osseous lamina, which was continuous with the lateral pterygoid plate and thus formed a wall of an apparent canal, which opened on the lateral side of the pterygoid process. This canal is referred to as an oval canal (canalis ovalis), instead of the foramen ovale. It runs superiorly, medially from the infratemporal fossa, and opens into the middle cranial fossa. The altered osseous morphology of this basicranial region may affect the course of the neurovascular structures which pass through the foramen ovale. As a consequence, clinical symptoms could occur, including paresthesiae of the inner aspect of the cheek and compression and neuralgia of the mandibular nerve or its branches