scholarly journals Accuracy of 2D Fluoroscopy with Preoperative CT Fused Neuronavigation in Thoracic and Lumbar Pedicle Screw Insertion

2020 ◽  
pp. 20-25
Author(s):  
Adrian Bălașa ◽  
Corina-Ionela Hurghiș ◽  
Flaviu Tămaș ◽  
Ioan-Alexandru Florian ◽  
Levente Peter ◽  
...  

Aim: Pedicle screw fixation is an established technique in the lumbar and thoracic area. Fluoroscopy-guided screw placement and subsequently navigation have decreased the rate of misplaced screws, but no technique has wholly eliminated this risk. This paper aims to study the difference between the accuracy of the fluoroscopic guided screw placement to that of the 2D fluoroscopy- preop CT fused neuronavigation guided technique, a lesser-used navigation technique.  Material and Methods: This retrospective study reflects our results using both techniques between March 2018 and March 2019 in both degenerative or traumatic spinal pathology for thoracic and lumbar regions. The accuracy of the screw placement was measured using Mirza grading system on postoperative CT images. Results: A total number of 56 patients underwent spinal instrumentation surgery. A total of 274 screws were placed with a mean number of 4.89 screws per patient; 199 screws were implanted using neuronavigation and 75 using the freehand-2D fluoroscopy-guided technique.  The accuracy rate of pedicle screw placement in the freehand technique guided by 2D fluoroscopy was 88,00%. With the use of neuronavigation, the accuracy increased to 89,96%. Conclusion:  Pedicle screw placement accuracy is higher when guided by CT-fluoro matching neuronavigation compared to freehand fluoroscopy-guided technique and can be used in departments where there is no intraoperative O-arm or 3D fluoroscopy available.

2017 ◽  
Vol 42 (5) ◽  
pp. E14 ◽  
Author(s):  
Granit Molliqaj ◽  
Bawarjan Schatlo ◽  
Awad Alaid ◽  
Volodymyr Solomiichuk ◽  
Veit Rohde ◽  
...  

OBJECTIVEThe quest to improve the safety and accuracy and decrease the invasiveness of pedicle screw placement in spine surgery has led to a markedly increased interest in robotic technology. The SpineAssist from Mazor is one of the most widely distributed robotic systems. The aim of this study was to compare the accuracy of robot-guided and conventional freehand fluoroscopy-guided pedicle screw placement in thoracolumbar surgery.METHODSThis study is a retrospective series of 169 patients (83 women [49%]) who underwent placement of pedicle screw instrumentation from 2007 to 2015 in 2 reference centers. Pathological entities included degenerative disorders, tumors, and traumatic cases. In the robot-assisted cohort (98 patients, 439 screws), pedicle screws were inserted with robotic assistance. In the freehand fluoroscopy-guided cohort (71 patients, 441 screws), screws were inserted using anatomical landmarks and lateral fluoroscopic guidance. Patients treated before 2009 were included in the fluoroscopy cohort, whereas those treated since mid-2009 (when the robot was acquired) were included in the robot cohort. Since then, the decision to operate using robotic assistance or conventional freehand technique has been based on surgeon preference and logistics. The accuracy of screw placement was assessed based on the Gertzbein-Robbins scale by a neuroradiologist blinded to treatment group. The radiological slice with the largest visible deviation from the pedicle was chosen for grading. A pedicle breach of 2 mm or less was deemed acceptable (Grades A and B) while deviations greater than 2 mm (Grades C, D, and E) were classified as misplacements.RESULTSIn the robot-assisted cohort, a perfect trajectory (Grade A) was observed for 366 screws (83.4%). The remaining screws were Grades B (n = 44 [10%]), C (n = 15 [3.4%]), D (n = 8 [1.8%]), and E (n = 6 [1.4%]). In the fluoroscopy-guided group, a completely intrapedicular course graded as A was found in 76% (n = 335). The remaining screws were Grades B (n = 57 [12.9%]), C (n = 29 [6.6%]), D (n = 12 [2.7%]), and E (n = 8 [1.8%]). The proportion of non-misplaced screws (corresponding to Gertzbein-Robbins Grades A and B) was higher in the robot-assisted group (93.4%) than the freehand fluoroscopy group (88.9%) (p = 0.005).CONCLUSIONSThe authors’ retrospective case review found that robot-guided pedicle screw placement is a safe, useful, and potentially more accurate alternative to the conventional freehand technique for the placement of thoracolumbar spinal instrumentation.


2021 ◽  
Author(s):  
Carlo Alberto Benech ◽  
Rosa Perez ◽  
Franco Benech ◽  
Torrey Shirk ◽  
Brandon Bucklen

Abstract Background: Traditional minimally invasive fluoroscopy-based techniques for pedicle screw placement utilize guidance, which may require fluoroscopic shots. Computerized tomography (CT) navigation results in more accurate screw placement. Robotic surgery seeks to establish access and trajectory with greater accuracy. Objective: This study evaluated the screw placement accuracy of a robotic platform.Methods: Demographic data, preoperative/postoperative CT scans, and complication rates of 127 patients who underwent lumbosacral pedicle screw placement with minimally invasive navigated robotic guidance using preoperative CT were analyzed. Results: On the GRS scale, 97.9% (711/726) of screws were graded A or B, 1.7% (12/726) of screws graded C, 0.4% (3/726) of screws graded D, and 0% graded E. Average offset from preoperative plan to final screw placement was 1.9 ± 1.5 mm from tip, 2.2 ± 1.4 mm from tail and 2.9 ± 2.3° of angulation.Conclusions: Robotic-assisted surgery utilizing preoperative CT workflow with intraoperative fluoroscopy-based registration improves pedicle screw placement accuracy within a patient’s pedicles.


Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Guang-Ting Cong ◽  
Avani Vaishnav ◽  
Joseph Barbera ◽  
Hiroshi Kumagai ◽  
James Dowdell ◽  
...  

Abstract INTRODUCTION Posterior spinal instrumentation for fusion using intraoperative computed tomography (CT) navigation is gaining traction as an alternative to the conventional two-dimensional fluoroscopic-guided approach to percutaneous pedicle screw placement. However, few studies to date have directly compared outcomes of these 2 minimally invasive instrumentation methods. METHODS A consecutive cohort of patients undergoing primary percutaneous posterior lumbar spine instrumentation for spine fusion was retrospectively reviewed. Revision surgeries or cases converted to open were excluded. Accuracy of screw placement was assessed using a postoperative CT scan with blinding to the surgical methods used. The Gertzbein-Robbins classification was used to grade cortical breach: Grade 0 (<0 mm cortical breach), Grade I (<2 mm), Grade II (2-4 mm), Grade III (4-6 mm), and Grade IV (>6 mm). RESULTS CT navigation was found to significantly improve accuracy of screw placement (P < .022). There was significantly more facet violation of the unfused level in the fluoroscopy group vs the CT group (9% vs 0.5%; P < .0001). There was also a higher proportion of poor screw placement in the fluoroscopy group (10.1% vs 3.6%). No statistical difference was found in the rate of tip breach, inferomedial breach, or lateral breach. Regression analysis showed that fluoroscopy had twice the odds of incurring poor screw placement as compared to CT navigation. CONCLUSION This radiographic study comparing screw placement in minimally invasive fluoroscopy- vs CT navigation-guided lumbar spine instrumentation provides evidence that CT navigation significantly improves accuracy of screw placement, especially in optimizing the screw trajectory so as to avoid facet violation. Long-term follow-up studies should be performed to ascertain whether this difference can contribute to an improvement in clinical outcomes.


2018 ◽  
Vol 46 (6) ◽  
pp. 2386-2397 ◽  
Author(s):  
Paerhati Rexiti ◽  
Yakufu Abulizi ◽  
Aikeremujiang Muheremu ◽  
Shuiquan Wang ◽  
Maierdan Maimaiti ◽  
...  

Objective To study the clinical application of lumbar isthmus parameters in guiding pedicle screw placement. Methods Lumbar isthmus parameters were measured in normal lumbar x-rays and cadaveric specimens from a Chinese Han population. Distance between the medial pedicle border and lateral isthmus border was recorded as a ‘D’ value and was compared between X-rays and cadavers. Orthopaedic surgeons estimated different distances (2–6 mm) and angles (5–20°), and bias ratios between estimated and real values were compared. Orthopaedic residents placed pedicle screws on cadaveric specimens before and after application of the ‘D’ value, and screw placement accuracy was compared. Results Except for L4 vertebrae, significant differences in the ‘D’ value were found between 25 cadaveric specimens and x-ray films from 120 patients. Distances and angles estimated by 40 surgeons were significantly different from all real values, except 2 mm distance. Accuracy of pedicle screw placement by six orthopaedic residents was significantly improved by applying the ‘D’ value. Conclusions Surgeon estimates of distance were more accurate than angle estimates. Addition of a ‘D’ value to conventional parameters may significantly improve pedicle screw placement accuracy in lumbar spine surgery.


Author(s):  
Tomohisa Inoue ◽  
Keiji Wada ◽  
Ayako Tominaga ◽  
Ryo Tamaki ◽  
Tomoya Hirota ◽  
...  

Neurosurgery ◽  
2000 ◽  
Vol 47 (2) ◽  
pp. 530-530 ◽  
Author(s):  
Kevin T. Foley ◽  
Ramesh L. Sahjpaul ◽  
Gerald R. Rodts

2018 ◽  
Vol 29 (3) ◽  
pp. 235-240 ◽  
Author(s):  
Martin H. Pham ◽  
Joshua Bakhsheshian ◽  
Patrick C. Reid ◽  
Ian A. Buchanan ◽  
Vance L. Fredrickson ◽  
...  

OBJECTIVEFreehand placement of C2 instrumentation is technically challenging and has a learning curve due the unique anatomy of the region. This study evaluated the accuracy of C2 pedicle screws placed via the freehand technique by neurosurgical resident trainees.METHODSThe authors retrospectively reviewed all patients treated at the LAC+USC Medical Center undergoing C2 pedicle screw placement in which the freehand technique was used over a 1-year period, from June 2016 to June 2017; all procedures were performed by neurosurgical residents. Measurements of C2 were obtained from preoperative CT scans, and breach rates were determined from coronal reconstructions on postoperative scans. Severity of breaches reflected the percentage of screw diameter beyond the cortical edge (I = < 25%; II = 26%–50%; III = 51%–75%; IV = 76%–100%).RESULTSNeurosurgical residents placed 40 C2 pedicle screws in 24 consecutively treated patients. All screws were placed by or under the guidance of Pham, who is a postgraduate year 7 (PGY-7) neurosurgical resident with attending staff privileges, with a PGY-2 to PGY-4 resident assistant. The authors found an average axial pedicle diameter of 5.8 mm, axial angle of 43.1°, sagittal angle of 23.0°, spinal canal diameter of 25.1 mm, and axial transverse foramen diameter of 5.9 mm. There were 17 screws placed by PGY-2 residents, 7 screws placed by PGY-4 residents, and 16 screws placed by the PGY-7 resident. The average screw length was 26.0 mm, with a screw diameter of 3.5 mm or 4.0 mm. There were 7 total breaches (17.5%), of which 4 were superior (10.0%) and 3 were lateral (7.5%). There were no medial breaches. The breaches were classified as grade I in 3 cases (42.9%), II in 3 cases (42.9%), III in 1 case (14.3%), and IV in no cases. There were 3 breaches that occurred via placement by a PGY-2 resident, 3 breaches by a PGY-4 resident, and 1 breach by the PGY-7 resident. There were no clinical sequelae due to these breaches.CONCLUSIONSFreehand placement of C2 pedicle screws can be done safely by neurosurgical residents in early training. When breaches occurred, they tended to be superior in location and related to screw length choice, and no breaches were found to be clinically significant. Controlled exposure to this unique anatomy is especially pertinent in the era of work-hour restrictions.


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