We describe a duplication of the odontoid process in a 6-year-old patient that included a partially fused midline ossicle on the anterior arch of C-1, fusion of the anterior lip of the foramen magnum and the arch of C-1, and an incomplete bony posterior arch of C-1.

Two patients with giant dumbbell foramen magnum neurinomas are reported. The intradural component was located anterior to the cervicomedullary junction while the extradural and extraspinal portion of the tumor had grown large enough to present as a neck swelling. In both patients total surgical removal was achieved by a single-stage posterior midline approach. Both patients had complete neurolo...

Occipitalization of the atlas is an osseous anomaly of the craniovertebral junction. The aim of this paper is to present an anatomical variant of the fused atlas with the occipital bone and discuss similar cases described in literature. The skull of an adult male analysed in this study belonged to the cranial collection of the Department of Anatomy of the Jagiellonian University, Medical Collag...

Three patients presented with hand wasting and weakness secondary to mid-cervical spinal cord compression. This was due to cervical spondylosis in two patients and a meningioma in one case. This phenomenon is probably similar to that seen with foramen magnum lesions and may be due to spinal cord ischemia distal to the compression, secondary to venous stasis.

Introduction Bony variations related to failure of segmentation of most caudal of the occipital sclerotomes, the pro-atlas, are rare, but have been documented [1]. The developmental failures lead to unusual bone formation at the anterior rim of foramen magnum, either in midline or laterally. Developmental osseous anomalies of the cranio-vertebral complex can result in neural compression, vascul...

During routine osteology demonstration of the posterior cranial fossa we noticed a transverse bony canal in the middle third of the clivus of an adult male skull. The canal was situated 1.8 cm in front the anterior border of the foramen magnum. The length of the canal was 0.6 cm long. The possible embryological basis and clinical significance of the variation was discussed.