[Navigation techniques in surgery of cranio-cervical junction and upper cervical spine]

Spinal navigation has substantially advanced during the past ten years. Surgeons have gained sufficient skills and confidence, and have introduced this technology to the anatomically challenging region of the upper cervical spine and craniocervical junction. The detailed evaluation of individual anatomy, rational pre-operative planning and final intraoperative control improve the safety and precision of classical surgical procedures. As methods technologically evolve, indication criteria change accordingly, but the basic principles of a relevatn choice remain; these are to reduce morbidity due to its three main causes, i.e., mechanical, neurological and vascular. We present an overview of current techniques and discuss their applicability in the region of the upper cervical spine and craniocervical junction. The systems allowing us to obtain live images intra-operatively, such as fluoroscopy or intra.operative CT, seem to be most versatile and accurate, especially when combined with traditional virtual navigation systems. Based on case histories, the authors suggest trends in the development of this field, with a focus on minimally invasive techniques. Key words: navigation, upper cervical spine, craniocervical junction.