The Surgical treatment of lesions of the ventral lesions of the (craniovertebral) junction is considered challenging, and until a few years ago these lesions were routinely managed by a conventional posterior approach despite the more rational and technically simpler alternative approach through the pharynx. Technological advances namely, the operating microscope, high-speed drill and extra-long surgical instruments have eliminated difficulties and allowed the transoral approach to become a relatively simple and safe operation.

The osseous structures that must be considered in planning such an operation is the subject of this study. The anatomical, embryological and surgical pathological literature is also reviewed.