Anatomical variations of skull base and craniocervical junction are of high clinical interest. Here, we describe the rare case of a combination of an anterior and a posterior proatlas manifestation in a West-European male. Posterolateral to the left occipital condyle we observed an irregular shaped posterior condylar process (processus condylicus posterior). Additionally, a median (or third) occipital condyle (condylus occipitalis tertius) at the anterior circumference of the foramen magnum was present. Clinically, proatlas manifestations may mimic fractures or tumors of the occipital bone, can lead to compression of surrounding structures, and might alter biomechanical properties of the craniocervical junction, potentially leading to neck pain in patients.
