Image-guided Thoracic Pedicle Screw Placement

Abstract OBJECTIVE Pedicle screw fixation in the lumbar spine has become the standard of care for various causes of spinal instability. However, because of the smaller size and more complex morphology of the thoracic pedicle, screw placement in the thoracic spine can be extremely challenging. In several published series, cortical violations have been reported in up to 50% of screws placed with standard fluoroscopic techniques. The goal of this study is to evaluate the accuracy of thoracic pedicle screw placement by use of image-guided techniques. METHODS During the past 4 years, 266 image-guided thoracic pedicle screws were placed in 65 patients at the University of Michigan Medical Center. Postoperative thin-cut computed tomographic scans were obtained in 52 of these patients who were available to enroll in the study. An impartial neuroradiologist evaluated 224 screws by use of a standardized grading scheme. All levels of the thoracic spine were included in the study. RESULTS Chart review revealed no incidence of neurological, cardiovascular, or pulmonary injury. Of the 224 screws reviewed, there were 19 cortical violations (8.5%). Eleven (4.9%) were Grade II (≤2 mm), and eight (3.6%) were Grade III (>2 mm) violations. Only five screws (2.2%), however, were thought to exhibit unintentional, structurally significant violations. Statistical analysis revealed a significantly higher rate of cortical perforation in the midthoracic spine (T4–T8, 16.7%; T1–T4, 8.8%; and T9–T12, 5.6%). CONCLUSION The low rate of cortical perforations (8.5%) and structurally significant violations (2.2%) in this retrospective series compares favorably with previously published results that used anatomic landmarks and intraoperative fluoroscopy. This study provides further evidence that stereotactic placement of pedicle screws can be performed safely and effectively at all levels of the thoracic spine.

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Image-guid ed thoracic pedicle screw placement: a technical study in cadavers and preliminary clinical experience

Neurosurgical FOCUS ◽

10.3171/foc.2001.10.2.3 ◽

2001 ◽

Vol 10 (2) ◽

pp. 1-5 ◽

Cited By ~ 6

Author(s):

Kee D. Kim ◽

J. Patrick Johnson ◽

Jesse D. Babbitz

Keyword(s):

Pedicle Screw ◽

Image Guidance ◽

Pedicle Screws ◽

Guidance System ◽

Basic Knowledge ◽

Screw Placement ◽

Pedicle Screw Placement ◽

Image Guided ◽

Thoracic Pedicle Screw ◽

Thoracic Pedicle Screws

Object Thoracic pedicle screw fixation is effective and reliable in providing short-segment stabilization. Although the procedure is becoming more widely used, accurate insertion of the screws is difficult due to the small dimensions of thoracic pedicles, and the associated risk is high due to the proximity of the spinal cord. In previous studies authors have shown the accuracy of image-guided lumbar pedicle screw placement, but there have been no reported investigations into the accuracy of image-guided thoracic pedicle screw placement. The authors report their experience with such an investigation. Methods To evaluate the accuracy of image-guided thoracic pedicle screw placement in vitro and in vivo, thoracic pedicle screws were placed with an image-guidance system in five human cadavers and 10 patients. In cadavers, the accuracy of screw placement was assessed by postoperative computerized tomography and visual inspection and in patients by postoperative imaging studies. Of the 120 pedicle screws placed in five cadavers pedicle violation occurred in 23 cases (19.2%); there was one pedicle violation (4.2%) in each of the last two cadavers. Of the 45 pedicle screws placed in 10 patients, pedicle violations occurred in three (6.7%). Conclusions In comparison with historical controls, the accuracy of thoracic pedicle screw placement is improved with the use of an image-guidance system. It allows the surgeon to visualize the thoracic pedicle and the surrounding structures that are normally out of the surgical field of view. The surgeon, however, must be aware of the limitations of an image-guidance system and have a sound basic knowledge of spinal anatomy to avoid causing serious complications.

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Variability Analysis of Manual and Computer-Assisted Preoperative Thoracic Pedicle Screw Placement Planning

Spine ◽

10.1097/brs.0000000000002659 ◽

2018 ◽

Vol 43 (21) ◽

pp. 1487-1495 ◽

Cited By ~ 2

Author(s):

Dejan Knez ◽

Janez Mohar ◽

Robert J. Cirman ◽

Boštjan Likar ◽

Franjo Pernuš ◽

...

Keyword(s):

Pedicle Screw ◽

Screw Placement ◽

Computer Assisted ◽

Pedicle Screw Placement ◽

Variability Analysis ◽

Thoracic Pedicle Screw

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Learning Retention of Thoracic Pedicle Screw Placement Using a High-Resolution Augmented Reality Simulator With Haptic Feedback

Operative Neurosurgery ◽

10.1227/neu.0b013e31821954ed ◽

2011 ◽

Vol 69 (suppl_1) ◽

pp. ons14-ons19 ◽

Cited By ~ 24

Author(s):

Cristian J Luciano ◽

P Pat Banerjee ◽

Brad Bellotte ◽

G Michael Oh ◽

Michael Lemole ◽

...

Keyword(s):

Augmented Reality ◽

Pedicle Screw ◽

Haptic Feedback ◽

Screw Placement ◽

Pedicle Screw Placement ◽

Data Set ◽

Learning Retention ◽

Performance Accuracy ◽

Thoracic Pedicle Screw ◽

Thoracic Pedicle Screws

Abstract BACKGROUND: We evaluated the use of a part-task simulator with 3D and haptic feedback as a training tool for a common neurosurgical procedure - placement of thoracic pedicle screws. OBJECTIVE: To evaluate the learning retention of thoracic pedicle screw placement on a high-performance augmented reality and haptic technology workstation. METHODS: Fifty-one fellows and residents performed thoracic pedicle screw placement on the simulator. The virtual screws were drilled into a virtual patient's thoracic spine derived from a computed tomography data set of a real patient. RESULTS: With a 12.5% failure rate, a 2-proportion z test yielded P = .08. For performance accuracy, an aggregate Euclidean distance deviation from entry landmark on the pedicle and a similar deviation from the target landmark in the vertebral body yielded P = .04 from a 2-sample t test in which the rejected null hypothesis assumes no improvement in performance accuracy from the practice to the test sessions, and the alternative hypothesis assumes an improvement. CONCLUSION: The performance accuracy on the simulator was comparable to the accuracy reported in literature on recent retrospective evaluation of such placements. The failure rates indicated a minor drop from practice to test sessions, and also indicated a trend (P = .08) toward learning retention resulting in improvement from practice to test sessions. The performance accuracy showed a 15% mean score improvement and more than a 50% reduction in standard deviation from practice to test. It showed evidence (P = .04) of performance accuracy improvement from practice to test session.

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