1448. Craniovertebral Fixation .....A New Technique with long term result.

Authors: Sushil Vasant Patkar, MD MS (PUNE, India)

Introduction: Ocassionally in craniovertebral instability the atlas and axis may not offer good fixation opportunity. In such circumstances realigning and stabilizing the skull on the spine along the line of weight transmission can become a challenge. A patient with polyostotic fibrous dysplasia of the upper four cervical vertebrae was treated by a new technoqie transferring the weight of the skull to the vertebral bodies anteriorly. Methods: A middle aged lady presented with quadriparesis of 6 mth duration.Imaging revealed osteolysis of uppermost 4 cervical vertebrae with deformity and severe upper cervical cord compression. After anterior cervical exposure contoured rods were passed paraspinally to reach the base of the skull posteriorly and the rods were fixed to the anterior cervical vertebrae . After turning the patient prone, using plates, rods and domino connectotrs the skull was fixed to the anterior cervical rods. Results: A new technique using a customized plate rod construct, fixed anteriorly to the mid cervical vertebrae (by a standard mid cervical exposure) with the rods contoured to reach posteriorly through the safe paraspinal corridor and connected with domino connectors to occipital plate rods fixed on either side of midline by additional posterior exposure avoiding the midline scar was planned and executed successfully . Long term (18 month) follow-up shows good position of implant with stable decompressed spine and new bone formation with good fusion. Conclusion: This construct transfers the weight of the cranium to the cervical vertebral bodies along the physiological line of weight transmission and can be considered for distraction and reduction of basilar invagination with atlantoaxial dislocation. The technique seems to be safe and reproducible , but will need to tested over time with more cases