Placement Of Pedicle Screws For Scoliosis Based On CT 3D Navigation System

Objective:As a new technique, CT three dimensional navigation system has been applied in orthopeadics wildly. However, few reports on a pedicle screw fixation method for scoliosis surgery using a navigation system have been published. This study tries to explain the clinical application and creature effect of this technique. Postoperative outcomes of pedicle screw fixation were evaluated in posterior scoliosis surgery with the use of navigation system.Methods:We targeted 18 cases in which segmental pedicle screw fixation had been performed using a navigation system at our hospital in one year. We inserted 264 pedicle screws in total, and we did not perform registration for each corpus vertebrate in order to shorten the duration of the surgery. We reviewed screw deviation among the items for review using Neo classification with postoperative CT images (1.25mm). For screw deviation in this case, grade 2or higher in the Neo classification system was designated as total deviation. Furthermore, we evaluated the registration period per corpus vertebrae, the complications, duration of surgery, blood loss, Cobb angle, and the correction rate.Results:In terms of screw deviation,11 (4.2%) of the 264 inserted screws were classified as total deviation. However, there were no neurovascular complications during or after surgery in any cases, and all cases maintained strong internal fixation. In the relationship between the use or nonuse of registration and the deviation, four screws (3.2%) in the corpus vertebrae for which registration was not performed had deviated. The duration of registration per corpus vertebrate averaged 4 min and 24 s (58-791 s), but registration also requires a learning curve, so the duration of registration per corpus vertebrae averaged 1 min and 14 s in more recent cases, thus marking a significant shortening.Conclusion:Pedicle screw fixation are excellent in regard to their fixing and correction force and have been clinically applied even in surgery for scoliosis, but the potential risk of neurovascular complications is unavoidable. The adoption of a navigation system in surgery for scoliosis is useful to increase the safety and certainty of the insertion of pedicle screws.Significant:Placement of pedicle screws for scoliosis has always been a difficult point in spinal internal fixation because of its risk. With the CT three dimensional navigation system's involvement this problem is solved perfectly. Performing by an experienced specialist who is familiar to the theory and manipulation of navigation system, this method makes segmental pedicle screws more secure and accurate. Patients will benefit much from this. As a result, this technique has bright application and prospects in spine.