CLINICAL ACCURACY AND SAFETY OF MINIMALLY INVASIVE LUMBOSACRAL PEDICLE SCREWS
Mohamed Abdel Bary, Yehia elhenawy, Yasser Elbanna and Ahmed Yehia
Department of Neurosurgery, Alexandria University.
Study Design: It is an examination of the accuracy of minimally invasive pedicle screw placement in the lumbosacral spine, using computed tomography scan. Objective. The primary objective of this study was to evaluate safety and clinical accuracy of, AP and lateral fluoroscopy for the minimally invasive placement, of lumbosacral pedicle screws. Summary of Background Data: The feasibility of the minimally invasive fusion techniques has been investigated in several studies; pedicle screw misplacement has been reported as one of the main complications. Methods: In this study, 50 consecutive patients with Single level segmental instability were investigated after minimally invasive fusion; Computed tomography scans of all instrumented pedicles from L3 to S1 were performed. Results: Out of 200 pedicle screws analyzed in, 191 screws did not violate any cortex only 9 screws from L3- S1 were misplaced (4.5%). The most frequent level with misplaced screws was in the S1 pedicle 4 out of 9 about 45%. The direction of screw misplacement was distributed as follows 3lateral and 6 (about 2/3) medial. Conclusion: Minimally invasive insertion of pedicle screws in the lumbosacral spine using AP and lateral fluoroscopy is a safe and reliable technique with low misplacement rate of only 4.5%.
June 2013