CT-navigation versus fluoroscopy-guided placement of pedicle screws at the thoracolumbar spine: single center experience of 4,500 screws

Abstract

Purpose Single center evaluation of the placement accuracy of thoracolumbar pedicle screws implanted either with fluoroscopy or under CT-navigation using 3D-reconstruction and intraoperative computed tomography control of the screw position. There is in fact a huge variation in the reported placement accuracy of pedicle screws, especially concerning the screw placement under conventional fluoroscopy most notably due to the lack of the definition of screw misplacement, combined with a potpourri of postinstrumentation evaluation methods. Methods The operation data of 1,006 patients operated on in our clinic between 1995 and 2005 is analyzed retrospectively. There were 2,422 screws placed with the help of CT-navigation compared to 2,002 screws placed under fluoroscopy. The postoperative computed tomography images were reviewed by a radiologist and an independent spine surgeon. Results In the lumbar spine, the placement accuracy was 96.4 % for CT-navigated screws and 93.9 % for pedicle screws placed under fluoroscopy, respectively. This difference in accuracy was statistically significant (Fishers Exact Test, p = 0.001). The difference in accuracy became more impressing in the thoracic spine, with a placement accuracy of 95.5 % in the CT-navigation group, compared to 79.0 % accuracy in the fluoroscopy group (p \ 0.001). Conclusion This study underlines the relevance of CT-navigation-guided pedicle screw placement, especially when instrumentation of the middle and upper thoracic spine is carried out.

Thoracolumbar instrumentation with CT-guided navigation (O-arm) in 270 consecutive patients: accuracy rates and lessons learned

“…14 However, our experience suggests that perhaps a larger volume of approximately [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] cases is required to demonstrate breach rates similar to those commonly reported in the literature. To our knowledge, the present report is the largest singlecenter series of thoracolumbar PSs placed using the O-arm and the first in the literature to quantify the learning curve for screw accuracy associ ated with this technology.…”

“…Computed tomography-based IGSS offers several advantages to the spine surgeon including greater accu racy of pedicle screw placement, 4,6,21,[24][25][26][27] minimal to no radiation exposure, 12,15,21,22 and potentially a short regis tration time. 5,[12][13][14] As with any new technology, CT-guid ed spinal surgery is prone to growing pains, which may force novice surgeons to abandon this technology early.…”

“…4,6,17,25,27 Consequently, imageguided spinal surgery (IGSS) has gained much momentum as an adjunct to in strumented thoracolumbar procedures. Currently, numer ous fluoroscopic (2D) and CT (3D) guidance systems are commercially available.…”

“…The CT-based systems have been demonstrated to be superior with accuracy rates reaching the high 90s. 21,26,27 However, intraoperative CT-guided spinal surgery is not without technical challenges. Inadvertent movement of registration markers, changes in patient anatomy af ter registration, and failure to maintain all tracking com ponents visible to the camera, as well as limited field of view in multilevel procedures, have all been reported as potential disadvantages of IGSS.…”

Reliability of the Planned Pedicle Screw Trajectory versus the Actual Pedicle Screw Trajectory using Intra-operative 3D CT and Image Guidance

“…[10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] Extensive literature has been published describing the technique, benefits, and drawbacks of each method, as well as comparisons between different approaches. [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45] With its increasing use has come a multitude of studies regarding the safety of this technique. Proper screw placement is imperative in order to avoid complications such as CSF leak, and pedicle fractures.…”