Editorial: Computed tomography and pedicle screws

2014 ◽  
Vol 21 (3) ◽  
pp. 317-319 ◽  
Author(s):  
Y. Raja Rampersaud
Keyword(s):  
Computed Tomography ◽  
Pedicle Screws

scholarly journals Confirmation of accuracy/inaccuracy of lumbar pedicle screw placement using postoperative computed tomography

2021 ◽  
Vol 12 ◽  
pp. 518
Author(s):  
Mohamed M. Arnaout ◽  
Magdy O. ElSheikh ◽  
Mansour A. Makia
Keyword(s):  
Computed Tomography ◽  
Lumbar Spine ◽  
Pedicle Screw ◽  
Pedicle Screws ◽  
Operative Intervention ◽  
Screw Placement ◽  
Lumbar Spine Surgery ◽  
Pedicle Screw Placement ◽  
Lumbar Pedicle ◽  
Ct Studies

Background: Transpedicular screws are extensively utilized in lumbar spine surgery. The placement of these screws is typically guided by anatomical landmarks and intraoperative fluoroscopy. Here, we utilized 2-week postoperative computed tomography (CT) studies to confirm the accuracy/inaccuracy of lumbar pedicle screw placement in 145 patients and correlated these findings with clinical outcomes. Methods: Over 6 months, we prospectively evaluated the location of 612 pedicle screws placed in 145 patients undergoing instrumented lumbar fusions addressing diverse pathology with instability. Routine anteroposterior and lateral plain radiographs were obtained 48 h after the surgery, while CT scans were obtained at 2 postoperative weeks (i.e., ideally these should have been performed intraoperatively or within 24–48 h of surgery). Results: Of the 612 screws, minor misplacement of screws (≤2 mm) was seen in 104 patients, moderate misplacement in 34 patients (2–4 mm), and severe misplacement in 7 patients (>4 mm). Notably, all the latter 7 (4.8% of the 145) patients required repeated operative intervention. Conclusion: Transpedicular screw insertion in the lumbar spine carries the risks of pedicle medial/lateral violation that is best confirmed on CT rather than X-rays/fluoroscopy alone. Here, we additional found 7 patients (4.8%) who with severe medial/lateral pedicle breach who warranting repeated operative intervention. In the future, CT studies should be performed intraoperatively or within 24–48 h of surgery to confirm the location of pedicle screws and rule in our out medial or lateral pedicle breaches.

Proposal of a New Safety Margin for Placement of C2 Pedicle Screws on Computed Tomography Angiography

2018 ◽  
Vol 120 ◽  
pp. e282-e289 ◽  
Author(s):  
Mohit Agrawal ◽  
Leve J. Devarajan ◽  
Pankaj K. Singh ◽  
Ajay Garg ◽  
Shashank S. Kale
Keyword(s):  
Computed Tomography ◽  
Computed Tomography Angiography ◽  
Safety Margin ◽  
Pedicle Screws

scholarly journals Placement of Guide-Wireless Sharp Percutaneous Pedicle Screws Utilizing Computed Tomography-Navigation and Sentinel Fluoroscopy: 2-Dimensional Operative Video

2019 ◽  
Vol 19 (2) ◽  
pp. E149-E150 ◽  
Author(s):  
Nikolay L Martirosyan ◽  
Joshua T Wewel ◽  
Juan S Uribe
Keyword(s):  
Computed Tomography ◽  
Pedicle Screw ◽  
Pedicle Screws ◽  
Transverse Process ◽  
Screw Placement ◽  
Osteoporotic Bone ◽  
Screw Insertion ◽  
Institutional Review ◽  
Stab Incision ◽  
Anterior Posterior

Abstract Many established techniques exist for minimally invasive pedicle screw placement. Nearly all techniques incorporate the use of a Kershner wire (K-wire) at various points in the work-flow. The use of a K-wire adds an additional step. If its position is lost, it requires repeating all previous steps, and placement is not without complication. The use of a guide-wireless sharp screws allows the surgeon to place a pedicle screw in 1 step with several fluid maneuvers.1 The patient underwent Institutional Review Board-approved consent for this study. Following traditional computed tomography-based navigation, a stab incision is made, followed by fascial dissection with monopolar cautery. The sharp screw is placed percutaneously at the facet-transverse process junction. The precise entry point is confirmed with navigation, followed by a sentinel anterior-posterior fluoroscopic image, verifying the accuracy of the navigation. The cortical bone is traversed by malleting the sharp tip through the cortex. When the cancellous bone is engaged, the screw is then advanced through the pedicle. This set of steps allows for safe, efficient placement of percutaneous pedicle screws without the need for a guidewire. Mal-placement regarding sharp pedicle screw insertion is similar to K-wire-dependent screw placement. Surgeons must be cognoscente of exceptionally sclerotic bone, which can prove difficult to cannulate. Conversely, osteoporotic bone that is liable to a cortical pedicle breach, transverse process fracture, and/or maltrajectory are all considerations when placing a K-wireless, sharp pedicle screw. Anterior-posterior fluoroscopy is utilized to confirm accuracy of image-guided navigation and mitigate malplacement of pedicle screws.

73. Analysis of Triggered Electromyographic Threshold of Thoracic Pedicle Screws Assessed by Computed Tomography

2007 ◽  
Vol 7 (5) ◽  
pp. 36S ◽  
Author(s):  
Jahangir Asghar ◽  
David Clements ◽  
Joshua Pahys ◽  
Amer Samdani ◽  
Linda D'Andrea ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Pedicle Screws ◽  
Thoracic Pedicle Screws

scholarly journals Cajas intersomáticas lumbares: ¿medios de fusión o solo espaciadores?

10.15417/211 ◽  
2013 ◽  
Vol 78 (2) ◽  
pp. 74
Author(s):  
Diego Nicolas Flores Kanter ◽  
Alberto Javier Jabif ◽  
Pablo Nicolás Ortiz
Keyword(s):  
Computed Tomography ◽  
Lumbar Spine ◽  
Lumbar Fusion ◽  
Pedicle Screws ◽  
Fusion Rate ◽  
Title Page ◽  
Anterior Fusion ◽  
Surgical Fusion ◽  
Circumferential Fusion ◽  
Spine Pathology

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p>RESUMEN</p><p><span>Introducción: </span><span>La fusión quirúrgica de la columna lumbar es un método muy utilizado para el tratamiento de la inestabilidad segmentaria lumbar dolorosa. En la actualidad, las dos técnicas de fusión instrumentada más utilizadas son la fusión posterolateral con tornillos pediculares y la fusión circunferencial mediante asociación de caja intersomática. Si bien hay evidencia de que la asociación de dispositivos intersomáticos aumenta la tasa de fusión, la mayoría de los estudios no discriminan si esta se produce solo de forma posterolateral o si se asocia una fusión anterior. El objetivo de este trabajo es determinar si existe fusión ósea real a nivel de las cajas intersomáticas o si estas actúan solo como espaciadores.</span></p><div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>Materiales y métodos: </span><span>Se analizaron 28 pacientes con patología de la columna lumbar sometidos a artrodesis lumbar circunferencial en un solo nivel entre mayo de 2007 y enero de 2012, mediante tomografía computarizada posquirúrgica para valorar la presencia o no de artrodesis anterior. Se efectuó un estudio de valor terapéutico, descriptivo, de observación (nivel de evidencia IV); mediante evaluación estadística se realizó un análisis de frecuencias para describir la proporción de casos con fusión anterior.</span></p></div></div><div class="layoutArea"><div class="column"><p><span>Resultados: </span><span>Se detectó una tasa de fusión del 92,86% y falta de fusión radiológica anterior en el 7,14% de los pacientes.</span></p><p><span>Conclusiones: </span><span>Hay una alta tasa de fusión anterior a nivel de las cajas intersomáticas; de este modo, se demuestra que dichos dispositivos actúan como medios de fusión y no solo como espaciadores.</span></p><div class="layoutArea"><div class="column"><p>PALABRAS CLAVE: Cajas intersomáticas. Fusión lumbar intersomática transforaminal. Tomografía computarizada.</p><p> </p><p>LUMBAR INTERBODY CAGES: FUSING MEANS OR ONLY SPACERS?</p></div></div><div class="layoutArea"><div class="column"><div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>Background: </span><span>Surgical fusion of the lumbar spine is a frequently used method for the treatment of painful lumbar segmental instability; currently the two instrumented fusion techniques most commonly used are posterolateral fusion with pedicle screws, and circumferential fusion by association of interbody cages. Although evidence shows that the association of intersomatic devices increases the fusion rate, most studies do not discriminate if this fusion occurs only posterolaterally, or an anterior fusion also occurs. The aim of this study is to determine if there is a true bone fusion at the level of interbody cages or if they act only as spacers.</span></p><div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>Methods: </span><span>We analyzed 28 patients with lumbar spine pathology surgically treated with one level circumferential lumbar fusion from May 2007 to January 2012, using post-surgical computed tomography, to assess the presence or absence of anterior arthrodesis. A therapeutic value, descriptive, observational study was conducted (evidence level IV); by statistical evaluation, frequency analysis was performed to describe the proportion of cases with anterior fusion.</span></p><div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>Results: </span><span>The fusion rate reached 92.86%; while there was no anterior radiological fusion in 7.14% of patients. </span></p><p><span>Conclusions: </span><span>There is a high rate of anterior fusion at the level of the interbody cages, thus demonstrating that these devices act as fusing means and not only as anterior spacers.</span></p><div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>KEY WORDS: Interbody cages; Transforaminal lumbsar interbody fusion. Computed tomography. </span></p></div></div></div><p><span><br /></span></p></div></div></div><p><span><br /></span></p></div></div></div><p><span><br /></span></p></div></div></div><p> </p></div></div><p><span><br /></span></p></div></div></div><p><span><br /></span></p></div></div></div><p> </p></div></div></div>

scholarly journals Insertion Angle of Pedicle Screws in the Subaxial Cervical Spine: The Analysis of Computed Tomography-Navigated Insertion of Pedicle Screws

2020 ◽  
Vol 14 (1) ◽  
pp. 66-71
Author(s):  
Stavros Oikonomidis ◽  
Frank Beyer ◽  
Carolin Meyer ◽  
Christoph Tobias Baltin ◽  
Peer Eysel ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Cervical Spine ◽  
Pedicle Screws ◽  
Insertion Angle ◽  
Subaxial Cervical Spine

scholarly journals Correlation between the Computed Tomography Values of the Screw Path and Pedicle Screw Pullout Strength: An Experimental Study in Porcine Vertebrae

2020 ◽  
Vol 14 (3) ◽  
pp. 265-272
Author(s):  
Atsushi Ikeura ◽  
Taketoshi Kushida ◽  
Kenichi Oe ◽  
Yoshihisa Kotani ◽  
Muneharu Ando ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Bone Mineral Density ◽  
Pedicle Screw ◽  
Bone Mineral ◽  
Lumbar Vertebrae ◽  
Pedicle Screws ◽  
Mineral Density ◽  
Screw Insertion ◽  
Pull Out ◽  
Pull Out Strength

Study Design: Biomechanical study.Purpose: To assess the correlation between the computed tomography (CT) values of the pedicle screw path and screw pull-out strength.Overview of Literature: The correlation between pedicle screw pull-out strength and bone mineral density has been well established. In addition, several reports have demonstrated a correlation between bone mineral density and CT values. However, no previous biomechanical studies investigated the correlation between CT values and pedicle screw pull-out strength.Methods: Sixty fresh-frozen lumbar vertebrae from 6-month-old pigs were used. Before screw insertion, the CT values of the screw path were obtained for each sample. Specimens were then randomly divided into three equal groups. Each group had one of three pedicle screws inserted: 4.0-mm LEGACY (4.0-LEG), 4.5-mm LEGACY (4.5-LEG), or 4.5-mm SOLERA (4.5-SOL) (all from Medtronic Sofamor Danek Inc., Memphis, TN, USA). Each screw had a consistent 30-mm thread length. Axial pull-out testing was performed at a rate of 1.0 mm/min. Correlations between the CT values and pedicle screw pull-out strength were evaluated using Pearson’s correlation coefficient analysis.Results: The correlation coefficients between the CT values of the screw path and pedicle screw pull-out strength for the 4.0-LEG, 4.5-LEG, and 4.5-SOL groups were 0.836 (<i>p</i> <0.001), 0.780 (<i>p</i> <0.001), and 0.873 (<i>p</i> <0.001), respectively. Greater CT values were associated with greater screw pull-out strength.Conclusions: The CT values of the screw path were strongly positively correlated with pedicle screw pull-out strength, regardless of the screw type and diameter, suggesting that the CT values could be clinically useful for predicting pedicle screw pull-out strength.

scholarly journals Intraoperative 3D imaging with cone-beam computed tomography leads to revision of pedicle screws in dorsal instrumentation: a retrospective analysis

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Felix Zimmermann ◽  
Katharina Kohl ◽  
Maxim Privalov ◽  
Jochen Franke ◽  
Sven Y. Vetter
Keyword(s):  
Computed Tomography ◽  
3D Imaging ◽  
Intraoperative Imaging ◽  
Pedicle Screws ◽  
Type A ◽  
Cone Beam ◽  
Type B ◽  
Intraoperative 3D Imaging ◽  
Screw Position ◽  
Type C

Abstract Background Correct positioning of pedicle screws can be challenging. Intraoperative imaging may be helpful. The purpose of this study was to evaluate the use of intraoperative 3D imaging with a cone-beam CT. The hypotheses were that intraoperative 3D imaging (1) will lead to an intraoperative revision of pedicle screws and (2) may diminish the rate of perforated screws on postoperative imaging. Methods Totally, 351 patients (age 60.9 ± 20.3 a (15–96); m/f 203/148) underwent dorsal instrumentation with intraoperative 3D imaging with 2215 pedicle screws at a trauma center level one. This study first evaluates intraoperative imaging. After this, 501 screws in 73 patients (age 62.5 ± 19.7 a; m/f 47/26) of this collective were included in the study group (SG) and their postoperative computed tomography was evaluated with regard to screw position. Then, 500 screws in 82 patients (age 64.8 ± 14.4 a; m/f 51/31) as control group (CG), who received the screws with conventional 2D fluoroscopy but without 3D imaging, were evaluated with regard to screw position. Results During the placement of the 2215 pedicle screws, 158 (7.0%) intraoperative revisions occurred as a result of 3D imaging. Postoperative computed tomography of the SG showed 445 (88.8%) screws without relevant perforation (type A + B), of which 410 (81.8%) could be classified as type A and 35 (7.0%) could be classified as type B. Fifty-six (11.2%) screws in SG showed relevant perforation (type C–E). In contrast, 384 (76.8%) screws in the CG were without relevant perforation (type A + B), of which 282 (56.4%) could be classified as type A and 102 (20.4%) as type B. One hundred and sixteen (23.2%) screws in the CG showed relevant perforation (type C–E). Conclusion This study shows that correct placement of pedicle screws in spine surgery with conventional 2D fluoroscopy is challenging. Misplacement of screws cannot always be prevented. Intraoperative 3D imaging with a CBCT can be helpful to detect and revise misplaced pedicle screws intraoperatively. The use of intraoperative 3D imaging will probably minimize the number of revision procedures due to perforating pedicle screws.

Accuracy of Image-Guided Pedicle Screw Placement Using Intraoperative Computed Tomography-Based Navigation With Automated Referencing, Part I: Cervicothoracic Spine

Neurosurgery ◽  
2011 ◽  
Vol 69 (4) ◽  
pp. 782-795 ◽  
Author(s):  
Kai-Michael Scheufler ◽  
Joerg Franke ◽  
Anke Eckardt ◽  
Hildegard Dohmen
Keyword(s):  
Computed Tomography ◽  
Spinous Process ◽  
Spinal Instrumentation ◽  
Pedicle Screws ◽  
Conventional Technique ◽  
Classification Systems ◽  
Angular Deviation ◽  
Intraoperative Computed Tomography ◽  
Image Guided ◽  
Thoracic Pedicle Screws

Abstract BACKGROUND: Image-guided spinal instrumentation reduces the incidence of implant misplacement. OBJECTIVE: To assess the accuracy of intraoperative computed tomography (iCT)-based neuronavigation (iCT-N). METHODS: In 35 patients (age range, 18-87 years), a total of 248 pedicle screws were placed in the cervical (C1-C7) and upper and midthoracic (T1-T8) spine. An automated iCT registration sequence was used for multisegmental instrumentation, with the reference frame fixed to either a Mayfield head clamp and/or the most distal spinous process within the instrumentation. Pediculation was performed with navigated drill guides or Jamshidi cannulas. The angular deviation between navigated tool trajectory and final implant positions (evaluated on postinstrumentation iCT or postoperative CT scans) was calculated to assess the accuracy of iCT-N. Final screw positions were also graded according to established classification systems. Mean follow-up was 16.7 months. RESULTS: Clinically significant screw misplacement or iCT-N failure mandating conversion to conventional technique did not occur. A total of 71.4% of patients self-rated their outcome as excellent or good at 12 months; 99.3% of cervical screws were compliant with Neo classification grades 0 and 1 (grade 2, 0.7%), and neurovascular injury did not occur. In addition, 97.8% of thoracic pedicle screws were assigned grades I to III of the Heary classification, with 2.2% grade IV placement. Accuracy of iCT-N progressively deteriorated with increasing distance from the spinal reference clamp but allowed safe instrumentation of up to 10 segments. CONCLUSION: Image-guided spinal instrumentation using iCT-N with automated referencing allows safe, highly accurate multilevel instrumentation of the cervical and upper and midthoracic spine. In addition, iCT-N significantly reduces the need for reregistration in multilevel surgery.

Sign in / Sign up

Export Citation Format

Share Document