Comparative Analysis of Pedicle Screw Placement in Children with Congenital Scoliosis: Freehand Technique (in vivo) and Guide Templates (in vitro)

Objective.To evaluate accuracy between pedicle screw placement in vertebral bodies achieved in vivo with freehand techniques versus their placement in vertebrae plastic models achieved in vitro with the use of guide templates, in toddlers and preschool children with congenital kyphoscoliosis of the thoracolumbar transition and lumbar spine amid the vertebral malformation.Material and Methods. The research is based on a retrospective analysis of the results of treatment of 10 patients with congenital kyphoscoliosis of the thoracolumbar transition and lumbar spine amid the vertebral malformation. Age – from 2 years 2 months to 6 years 8 months old (mean 3 years 8 months old), gender – 6 boys, 4 girls. Based on the postoperative multi-slice spiral computed tomography (MSCT) of the spine, the pedicle screws placement accuracy of the correcting multi-support metalwork was evaluated. These patients constituted the 1st research group (in vivo group). The 2nd research group (in vitro group) was formed from 27 vertebrae plastic models with pedicle screws inserted in them with the use of guide templates. The placement accuracy of the installed pedicle support elements was assessed based on the S.D. Gertzbein et al. scale (1990).Results. In the 1st group, there were 52 pedicle screws placed. The screw placement accuracy according to the rate of misplacement, as follows: 53.8% in Grade 0, 25% in Grade I, 11.6% in Grade II, 9.6% in Grade III. The number of screws with the rate of misplacement in Grade 0 + Grade I was 41 (78.8%). In the 2nd group, there were 54 screws placed and slightly larger than the 1st group. The screw placement accuracy according to the rate of misplacement was 94.4% in Grade 0, 1.9% in Grade I, 3.7% in Grade II, respectively. The number of screws with the rate of misplacement in Grade 0 + Grade I was 52 (96.3%).Conclusions.Comparative analysis showed that the number of pedicle screws successfully placed in vertebrae plastic models in children with congenital deformities of the thoracolumbar transition and lumbar spine achieved with the use of guide templates was significantly higher than the number of screws successfully placed with freehand techniques (96.3% versus 80.8%, p = 0.011). The results obtained with method of navigation templates in vitro showed high precision and accuracy of pedicle screw placement which gives the prospect for using this type of navigation in clinical practice in toddlers with congenital scoliosis.

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

Surgical Neurology International ◽

10.25259/sni_290_2021 ◽

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.

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Anatomical and radiologic characteristics of isthmus parameters in guiding pedicle screw placement

Journal of International Medical Research ◽

10.1177/0300060518762986 ◽

2018 ◽

Vol 46 (6) ◽

pp. 2386-2397 ◽

Cited By ~ 1

Author(s):

Paerhati Rexiti ◽

Yakufu Abulizi ◽

Aikeremujiang Muheremu ◽

Shuiquan Wang ◽

Maierdan Maimaiti ◽

...

Keyword(s):

Pedicle Screw ◽

Pedicle Screws ◽

Screw Placement ◽

Lumbar Spine Surgery ◽

X Rays ◽

Pedicle Screw Placement ◽

Chinese Han ◽

Before And After ◽

Placement Accuracy ◽

D Value

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.

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Application of a novel customized guide template in percutaneous pedicle screw placement: an in vitro study

10.29007/qzxg ◽

2018 ◽

Author(s):

Su-Hua Wu ◽

Guo Zheng ◽

Jian-Hua Chen ◽

Sheng-Hai Wang

Keyword(s):

Pedicle Screw ◽

Average Distance ◽

Pedicle Screws ◽

Screw Placement ◽

Patient Specific ◽

Pedicle Screw Placement ◽

Intraoperative Radiation ◽

Spine Stabilization ◽

Percutaneous Pedicle Screw

In open surgery for spine stabilization, the pedicle screws are often placed using patient-specific guide templates since they can improve the screw placement accuracy and simplify surgery. However, the conventional fit-and-lock template requires full exposure of the bony structures and is therefore not suitable for minimally invasive procedures. In this study, we constructed a novel guide template for percutaneous pedicle screw placement. Its feasibility and the accuracy of template-assisted pedicle screw placement were assessed using an excised calf spine model. As a result, all inserted guide wires and 27 of 30 simulated screws (90%) were completely in the pedicle. The remaining screws (10%) penetrated by less than 2 mm. The average distance and angular deviations of the guide wires were 1.46±0.60 mm and 1.10±0.84°. Our study demonstrate that this novel guide template is technically feasible and enhances the accuracy of percutaneous pedicle screw placement. Moreover, it may simplify the surgery and minimize intraoperative radiation. Further research on its clinical applications is warranted.

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Accuracy of Free-Hand Pedicle Screws in the Thoracic and Lumbar Spine: Analysis of 6816 Consecutive Screws

Neurosurgery ◽

10.1227/neu.0b013e3181fdfaf4 ◽

2011 ◽

Vol 68 (1) ◽

pp. 170-178 ◽

Cited By ~ 132

Author(s):

Scott L. Parker ◽

Matthew J. McGirt ◽

S Harrison. Farber ◽

Anubhav G. Amin ◽

Anne-Marie. Rick ◽

...

Keyword(s):

Lumbar Spine ◽

Radiation Exposure ◽

Pedicle Screw ◽

Pedicle Screws ◽

Screw Placement ◽

Pedicle Screw Placement ◽

Intraoperative Fluoroscopy ◽

Thoracic And Lumbar Spine ◽

Institutional Experience ◽

Screw Diameter

Abstract BACKGROUND: Pedicle screws are used to stabilize all 3 columns of the spine, but can be technically demanding to place. Although intraoperative fluoroscopy and stereotactic-guided techniques slightly increase placement accuracy, they are also associated with increased radiation exposure to patient and surgeon as well as increased operative time. OBJECTIVE: To describe and critically evaluate our 7-year institutional experience with placement of pedicle screws in the thoracic and lumbar spine using a free-hand technique. METHODS: We retrospectively reviewed records of all patients undergoing free-hand pedicle screw placement without fluoroscopy in the thoracic or lumbar spine between June 2002 and June 2009. Incidence and extent of cortical breach by misplaced pedicle screw was determined by review of postoperative computed tomography scans. We defined breach as more than 25% of the screw diameter residing outside of the pedicle or vertebral body cortex. RESULTS: A total of 964 patients received 6816 free-hand placed pedicle screws in the thoracic or lumbar spine. Indications for hardware placement were degenerative/deformity disease (51.2%), spondylolisthesis (23.7%), tumor (22.7%), trauma (11.3%), infection (7.6%), and congenital (0.9%). A total of 115 screws (1.7%) were identified as breaching the pedicle in 87 patients (9.0%). Breach occurred more frequently in the thoracic than the lumbar spine (2.5% and 0.9%, respectively; P < .0001) and was more often lateral (61.3%) than medial (32.8%) or superior (2.5%). T4 (4.1%) and T6 (4.0%) experienced the highest breach rate, whereas L5 and S1 had the lowest breach rate. Eight patients (0.8%) underwent revision surgery to correct malpositioned screws. CONCLUSION: Free-hand pedicle screw placement based on external anatomy alone can be performed with acceptable safety and accuracy and allows avoidance of radiation exposure encountered in fluoroscopic techniques. Image-guided assistance may be most valuable when placing screws between T4 and T6, where breach rates are highest.

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Analysis of the Effectiveness of Guide Templates for the Placement of Pedicle Screws in the Surgical Treatment of Children with Congenital Scoliosis

Research Institute of Traumatology and Orthopedics ◽

10.52889/1684-9280-2020-3-53-13-17 ◽

2020 ◽

Vol 3 (53) ◽

pp. 13-17

Author(s):

Sergei Vissarionov ◽

◽

Alexey Baindurashvili ◽

Dmitriy Kokushin ◽

Nikita Khusainov ◽

...

Keyword(s):

Comparative Analysis ◽

Preschool Children ◽

Lumbar Spine ◽

Pedicle Screws ◽

Congenital Scoliosis ◽

Thoracolumbar Junction ◽

Congenital Deformities ◽

Vertebral Bodies

Objective: to conduct a comparative analysis of the correct position of transpedicular screws installed in the vertebral bodies in young and preschool children with congenital kyphoscoliosis of the thoracolumbar junction and lumbar spine against the background of abnormal formation of the vertebrae by the "free hand" method in vivo and in plastic models of vertebrae using templates -Directors in vitro. Methods. A comparative analysis of the correctness of the position of transpedicular screws installed in the vertebral bodies in young and preschool children with congenital kyphoscoliosis of the thoracolumbar junction and lumbar spine against the background of a violation of the formation of the vertebrae by the "free hand" method in vivo and in plastic models of the vertebrae using guide templates in vitro. Results. The number of correctly inserted transpedicular screws in plastic models of the vertebrae of children with congenital deformities of the thoracolumbar and lumbar spine using guide templates was significantly higher than the number of correctly installed screws using the free hand method (96.3% versus 80.8%, p = 0.011). Conclusion. The obtained results of in vitro guide templates application showed high accuracy and correctness of pedicle screw placement, which gives prospects for the use of this type of navigation in clinical practice in young children with congenital scoliosis.

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Postoperative Assessment of Pedicle Screws and Management of Breaches: A Survey among Canadian Spine Surgeons and a New Scoring System

Asian Spine Journal ◽

10.4184/asj.2018.12.1.37 ◽

2018 ◽

Vol 12 (1) ◽

pp. 37-46 ◽

Cited By ~ 3

Author(s):

Ahmed Aoude ◽

Saber Ghadakzadeh ◽

Hamzah Alhamzah ◽

Maryse Fortin ◽

Peter Jarzem ◽

...

Keyword(s):

Pedicle Screw ◽

Scoring System ◽

Accuracy Assessment ◽

Pedicle Screws ◽

Sensory Loss ◽

Screw Placement ◽

X Rays ◽

Pedicle Screw Placement ◽

Asymptomatic Patients ◽

Placement Accuracy

<sec><title>Study Design</title>This study was designed as a survey amongst Canadian spine surgeon to determine a scoring system to standardize pedicle screw placement assessment.</sec><sec><title>Purpose</title>This study aimed to obtain and analyze the opinions of spine surgeons regarding the assessment of pedicle screw accuracy, with the goal of establishing clinical guidelines for interventions for malpositioned pedicle screws.</sec><sec><title>Overview of Literature</title>Accurate placement of pedicle screws is challenging, and misalignment can lead to various complications. To date, there is no recognized gold standard for assessing pedicle screw placement accuracy. The literature is lacking studies attempting to standardize pedicle screw placement accuracy assessment.</sec><sec><title>Methods</title>A survey of the clinical methods and imaging criteria that are used for assessing pedicle screw placement accuracy was designed and sent to orthopedic and neurosurgery spine surgeons from the Canadian Spine Society for their anonymous participation.</sec><sec><title>Results</title>Thirty-five surgeons completed the questionnaire. The most commonly used modalities for assessing pedicle screw position postoperatively were plain X-rays (97%) and computed tomography (CT, 97%). In both symptomatic and asymptomatic patients, the most and least worrisome breaches were medial and anterior breaches, respectively. The majority of surgeons tended not to re-operate on asymptomatic breaches. More than 60% of surgeons would re-operate on patients with new-onset pain and a ≤4-mm medial or inferior breach in both thoracic and lumbar regions. If a patient experienced sensory loss and a breach on CT, in either the thoracic or lumbar levels, 90% and 70% of the surgeons would re-operate for a medial breach and an inferior breach, respectively.</sec><sec><title>Conclusions</title>Postoperative clinical presentation and imaging findings are crucial for interpreting aberrant pedicle screw placement. This study presents a preliminary scoring system for standardizing the classification of pedicle screws.</sec>

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Is in vivo manual palpation for thoracic pedicle screw instrumentation reliable?

Journal of Neurosurgery Spine ◽

10.3171/2014.1.spine13197 ◽

2014 ◽

Vol 20 (5) ◽

pp. 492-496 ◽

Cited By ~ 6

Author(s):

Miriam L. Donohue ◽

Ross R. Moquin ◽

Amit Singla ◽

Blair Calancie

Keyword(s):

Pedicle Screw ◽

Pedicle Screws ◽

Alternative Methods ◽

Screw Placement ◽

Pedicle Screw Placement ◽

Thoracic Pedicle Screw ◽

Thoracic Pedicle Screws ◽

Screw Position ◽

Manual Palpation

Object Previous reports on the accuracy of manual palpation for thoracic pedicle screw placement have been restricted to cadaveric studies. Authors of the present novel study assessed the accuracy of manual palpation for the detection of medial and lateral pedicle breaches during thoracic spine surgery in living adult humans. Methods Pedicle tracks were created freehand and manually palpated using a ball-tipped probe. Postoperative CT scans of all implanted thoracic and L-1 screws were evaluated with respect to screw position and the pedicle wall. Results Five hundred twenty-five pedicle track/screw placements were compared. There were 21 pedicles with medial breaches measuring ≥ 2 mm. The surgeon correctly identified only 4 of these pedicle tracks as having a medial breach. The surgeon correctly identified 17 of 128 pedicles with a significant (≥ 2 mm) lateral breach. One hundred two screw placements had no measurable breach in any direction (medial, lateral, or foraminal). The surgeon correctly identified 98% of these ideally placed screws. Conclusions In this real-time study of thoracic pedicle screw placement, the accuracy of manual palpation for detecting medial or lateral breaches that were ≥ 2 mm was disturbingly low. These findings are consistent with those in recent cadaveric evaluations of palpation accuracy and point to the critical need for more reliable alternative methods to assess pedicle integrity during the placement of thoracic pedicle screws for spine instrumentation surgery.

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A Quantitative Accuracy Assessment of The Use of A Rigid Robotic Arm In Navigated Placement of 726 Pedicle Screws

10.21203/rs.3.rs-588342/v1 ◽

2021 ◽

Author(s):

Carlo Alberto Benech ◽

Rosa Perez ◽

Franco Benech ◽

Torrey Shirk ◽

Brandon Bucklen

Keyword(s):

Minimally Invasive ◽

Pedicle Screw ◽

Accuracy Assessment ◽

Demographic Data ◽

Pedicle Screws ◽

Screw Placement ◽

Complication Rates ◽

Pedicle Screw Placement ◽

Preoperative Ct ◽

Placement Accuracy

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.

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Three-dimensional assessment of robot-assisted pedicle screw placement accuracy and instrumentation reliability based on a preplanned trajectory

Journal of Neurosurgery Spine ◽

10.3171/2020.3.spine20208 ◽

2020 ◽

Vol 33 (4) ◽

pp. 519-528

Author(s):

Bowen Jiang ◽

Zach Pennington ◽

Alex Zhu ◽

Stavros Matsoukas ◽

A. Karim Ahmed ◽

...

Keyword(s):

Pedicle Screw ◽

Tertiary Care ◽

Pedicle Screws ◽

Screw Placement ◽

Lumbosacral Spine ◽

Grading System ◽

Angular Deviation ◽

Pedicle Screw Placement ◽

Placement Accuracy ◽

The Mean

OBJECTIVERobotic spine surgery systems are increasingly used in the US market. As this technology gains traction, however, it is necessary to identify mechanisms that assess its effectiveness and allow for its continued improvement. One such mechanism is the development of a new 3D grading system that can serve as the foundation for error-based learning in robot systems. Herein the authors attempted 1) to define a system of providing accuracy data along all three pedicle screw placement axes, that is, cephalocaudal, mediolateral, and screw long axes; and 2) to use the grading system to evaluate the mean accuracy of thoracolumbar pedicle screws placed using a single commercially available robotic system.METHODSThe authors retrospectively reviewed a prospectively maintained, IRB-approved database of patients at a single tertiary care center who had undergone instrumented fusion of the thoracic or lumbosacral spine using robotic assistance. Patients with preoperatively planned screw trajectories and postoperative CT studies were included in the final analysis. Screw accuracy was measured as the net deviation of the planned trajectory from the actual screw trajectory in the mediolateral, cephalocaudal, and screw long axes.RESULTSThe authors identified 47 patients, 51% male, whose pedicles had been instrumented with a total of 254 screws (63 thoracic, 191 lumbosacral). The patients had a mean age of 61.1 years and a mean BMI of 30.0 kg/m2. The mean screw tip accuracies were 1.3 ± 1.3 mm, 1.2 ± 1.1 mm, and 2.6 ± 2.2 mm in the mediolateral, cephalocaudal, and screw long axes, respectively, for a net linear deviation of 3.6 ± 2.3 mm and net angular deviation of 3.6° ± 2.8°. According to the Gertzbein-Robbins grading system, 184 screws (72%) were classified as grade A and 70 screws (28%) as grade B. Placement of 100% of the screws was clinically acceptable.CONCLUSIONSThe accuracy of the discussed robotic spine system is similar to that described for other surgical systems. Additionally, the authors outline a new method of grading screw placement accuracy that measures deviation in all three relevant axes. This grading system could provide the error signal necessary for unsupervised machine learning by robotic systems, which would in turn support continued improvement in instrumentation placement accuracy.

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Real-time navigation guidance with intraoperative CT imaging for pedicle screw placement using an augmented reality head-mounted display: a proof-of-concept study

Neurosurgical FOCUS ◽

10.3171/2021.5.focus21209 ◽

2021 ◽

Vol 51 (2) ◽

pp. E11

Author(s):

Daniel S. Yanni ◽

Burak M. Ozgur ◽

Robert G. Louis ◽

Yevgenia Shekhtman ◽

Rajiv R. Iyer ◽

...

Keyword(s):

Lumbar Spine ◽

Augmented Reality ◽

Real Time ◽

Pedicle Screw ◽

User Feedback ◽

Screw Placement ◽

Pedicle Screw Placement ◽

Head Mounted Display ◽

Placement Accuracy ◽

Grading Scale

OBJECTIVE Augmented reality (AR) has the potential to improve the accuracy and efficiency of instrumentation placement in spinal fusion surgery, increasing patient safety and outcomes, optimizing ergonomics in the surgical suite, and ultimately lowering procedural costs. The authors sought to describe the use of a commercial prototype Spine AR platform (SpineAR) that provides a commercial AR head-mounted display (ARHMD) user interface for navigation-guided spine surgery incorporating real-time navigation images from intraoperative imaging with a 3D-reconstructed model in the surgeon's field of view, and to assess screw placement accuracy via this method. METHODS Pedicle screw placement accuracy was assessed and compared with literature-reported data of the freehand (FH) technique. Accuracy with SpineAR was also compared between participants of varying spine surgical experience. Eleven operators without prior experience with AR-assisted pedicle screw placement took part in the study: 5 attending neurosurgeons and 6 trainees (1 neurosurgical fellow, 1 senior orthopedic resident, 3 neurosurgical residents, and 1 medical student). Commercially available 3D-printed lumbar spine models were utilized as surrogates of human anatomy. Among the operators, a total of 192 screws were instrumented bilaterally from L2–5 using SpineAR in 24 lumbar spine models. All but one trainee also inserted 8 screws using the FH method. In addition to accuracy scoring using the Gertzbein-Robbins grading scale, axial trajectory was assessed, and user feedback on experience with SpineAR was collected. RESULTS Based on the Gertzbein-Robbins grading scale, the overall screw placement accuracy using SpineAR among all users was 98.4% (192 screws). Accuracy for attendings and trainees was 99.1% (112 screws) and 97.5% (80 screws), respectively. Accuracy rates were higher compared with literature-reported lumbar screw placement accuracy using FH for attendings (99.1% vs 94.32%; p = 0.0212) and all users (98.4% vs 94.32%; p = 0.0099). The percentage of total inserted screws with a minimum of 5° medial angulation was 100%. No differences were observed between attendings and trainees or between the two methods. User feedback on SpineAR was generally positive. CONCLUSIONS Screw placement was feasible and accurate using SpineAR, an ARHMD platform with real-time navigation guidance that provided a favorable surgeon-user experience.

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