scholarly journals A New Coupling Method for Accurate Measurement of Pedicle Screw Electrical Properties for Surgical Procedures

2021 ◽  
Vol 11 (21) ◽  
pp. 9861
Author(s):  
Pedro Fonseca ◽  
Márcio Fagundes Goethel ◽  
Ricardo Sebastião ◽  
Manoela Vieira Sousa ◽  
João Paulo Vilas-Boas ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Electrical Properties ◽  
Pedicle Screw ◽  
Electrical Resistance ◽  
Spinal Surgery ◽  
Pedicle Screws ◽  
Direct Application ◽  
Coupling Method ◽  
Electrical Analysis ◽  
A Current

The objective of this study is to present a new coupling method in order to measure the electrical properties of titanium alloy pedicle screws used in spinal surgery and to compare it with other common methods of measurement. An experimental setup was devised to test the electrical resistance of two specimens of pedicle screws using four methods for coupling the sensing leads, including the use of multimeter probes, alligator clips, wrapped wires and encapsulation with thermo-retractable sleeves. The electrical resistance of the pedicle screw under testing was measured at a current of 10 mA for each coupling method, and the results compared. Our findings show that although widely used in electrical analysis, the alligator clips do not perform as well as the other methods, such as simple wrapping of wires around the screw or the direct application of multimeter probes. The use of thermo-retractable sleeves provides the lowest resistance and inter-quartile range and is closer to the tabled values for the screw’s titanium alloy. Additionally, only this method allows the measurement of identical resistivity values between different screw models manufactured with the same titanium alloy. We then concluded that the use of wrapped wires encapsulated with thermo-retractable sleeves allow more accurate measurements of the pedicle screw’s electrical properties.

Image-Guided Spinal Surgery and Robotics in MIS: Where Are We Now?

2018 ◽  
Vol 1 (2) ◽  
pp. 2
Author(s):  
Chiung Chyi Shen
Keyword(s):  
Pedicle Screw ◽  
Spinal Surgery ◽  
Surgical Navigation ◽  
Improve Patient Safety ◽  
Intraoperative Imaging ◽  
Spinal Instrumentation ◽  
Pedicle Screws ◽  
Computer Assisted ◽  
Navigation Systems ◽  
Image Guided

Use of pedicle screws is widespread in spinal surgery for degenerative, traumatic, and oncological diseases. The conventional technique is based on the recognition of anatomic landmarks, preparation and palpation of cortices of the pedicle under control of an intraoperative C-arm (iC-arm) fluoroscopy. With these conventional methods, the median pedicle screw accuracy ranges from 86.7% to 93.8%, even if perforation rates range from 21.1% to 39.8%.The development of novel intraoperative navigational techniques, commonly referred to as image-guided surgery (IGS), provide simultaneous and multiplanar views of spinal anatomy. IGS technology can increase the accuracy of spinal instrumentation procedures and improve patient safety. These systems, such as fluoroscopy-based image guidance ("virtual fluoroscopy") and computed tomography (CT)-based computer-guidance systems, have sensibly minimized risk of pedicle screw misplacement, with overall perforation rates ranging from between 14.3% and 9.3%, respectively."Virtual fluoroscopy" allows simultaneous two-dimensional (2D) guidance in multiple planes, but does not provide any axial images; quality of images is directly dependent on the resolution of the acquired fluoroscopic projections. Furthermore, computer-assisted surgical navigation systems decrease the reliance on intraoperative imaging, thus reducing the use of intraprocedure ionizing radiation. The major limitation of this technique is related to the variation of the position of the patient from the preoperative CT scan, usually obtained before surgery in a supine position, and the operative position (prone). The next technological evolution is the use of an intraoperative CT (iCT) scan, which would allow us to solve the position-dependent changes, granting a higher accuracy in the navigation system. 

scholarly journals Biomechanical Evaluation of Cortical Bone Trajectory Fixation with Traditional Pedicle Screw in the Lumbar Spine: A Finite Element Study

2021 ◽  
Vol 11 (22) ◽  
pp. 10583
Author(s):  
Kuo-Chih Su ◽  
Kun-Hui Chen ◽  
Chien-Chou Pan ◽  
Cheng-Hung Lee
Keyword(s):  
Finite Element ◽  
Lumbar Spine ◽  
Cortical Bone ◽  
Pedicle Screw ◽  
Spinal Surgery ◽  
Pedicle Screws ◽  
Element Model ◽  
Cortical Bone Trajectory ◽  
Significant Difference ◽  
Flexion Extension

Cortical bone trajectory (CBT) is increasingly used in spinal surgery. Although there are many biomechanical studies, the biomechanical effect of CBT in combination with traditional pedicle screws is not detailed. Therefore, the purpose of this study was to investigate the effects of the traditional pedicle screw and CBT screw implantation on the lumbar spine using finite element methods. Based on the combination of the traditional pedicle screw and the CBT system implanted into the lumbar spine, four finite element spinal lumbar models were established. The models were given four different load conditions (flexion, extension, lateral bending, and axial rotation), and the deformation and stress distribution on the finite element model were observed. The results show that there was no significant difference in the structural stability of the lumbar spine model between the traditional pedicle screw system and the CBT system. In addition, CBT may reduce stress on the endplate. Different movements performed by the model may have significant biomechanical effects on the spine and screw system. Clinical spinal surgeons may also consider using the CBT system in revision spinal surgery, which may contribute to smaller wounds.

scholarly journals The accuracy of multi-slice three-dimensional computerized tomography on the verification of the pedicle screw trajectory

2009 ◽  
Vol 1 (1) ◽  
pp. 22
Author(s):  
Suat Erol Çelik ◽  
Bilal Kelten ◽  
Recai Gökcan ◽  
Ahmet Cevri Yıldız
Keyword(s):  
Pedicle Screw ◽  
Computerized Tomography ◽  
Spinal Surgery ◽  
Three Dimensional ◽  
Pedicle Screws ◽  
Ct Reconstruction ◽  
Axial Ct ◽  
Diagnostic Power ◽  
Ct Slices

The purpose of our study was to determine the diagnostic power of three-dimensional reformatted multi-slice computerized tomography (CT) images on misplaced pedicle screws in spinal surgery. Eighty-four consecutive patients with 458 screws in situ were investigated prospectively using both axial CT slices and reformatted images after operation by two blinded investigators. All the screw misplacements were documented and the differences between the two imaging modalities were recorded. Axial CT slices were able to show only 23 of 60 misplaced pedicle screws; multi-slice CT was three times more powerful in the diagnosis of pedicle screw complications in spinal surgery (p<0.05). We concluded that multi-slice CT reconstruction should be the primary diagnostic tool after screw implantation in the human spine.

Less Invasive Pediatric Spinal Deformity Surgery: The Case for Robotic-Assisted Placement of Pedicle Screws

2021 ◽  
pp. 155633162110278
Author(s):  
Kyle W. Morse ◽  
Hila Otremski ◽  
Kira Page ◽  
Roger F. Widmann
Keyword(s):  
Pedicle Screw ◽  
Current Literature ◽  
Spinal Deformity ◽  
Spinal Surgery ◽  
Pedicle Screws ◽  
Screw Placement ◽  
Pedicle Screw Placement ◽  
Robotic Assisted ◽  
Less Invasive ◽  
Spinal Deformity Surgery

Introduction: Pediatric spinal deformity involves a complex 3-dimensional (3D) deformity that increases the risk of pedicle screw placement due to the close proximity of neurovascular structures. To increase screw accuracy, improve patient safety, and minimize surgical complications, the placement of pedicle screws is evolving from freehand techniques to computer-assisted navigation and to the introduction of robotic-assisted placement. Purpose: The aim of this review was to review the current literature on the use of robotic navigation in pediatric spinal deformity surgery to provide both an error analysis of these techniques and to provide recommendations to ensure its safe application. Methods: A narrative review was conducted in April 2021 using the MEDLINE (PubMed) database. Studies were included if they were peer-reviewed retrospective or prospective studies, included pediatric patients, included a primary diagnosis of pediatric spine deformity, utilized robotic-assisted spinal surgery techniques, and reported thoracic or lumbar pedicle screw breach rates or pedicle screw malpositioning. Results: In the few studies published on the use of robotic techniques in pediatric spinal deformity surgery, several found associations between the technology and increased rates of screw placement accuracy, reduced rates of breach, and minimal complications. All were retrospective studies. Conclusions: Current literature is of a low level of evidence; nonetheless, the findings suggest the accuracy and safety of robotic-assisted spinal surgery in pediatric pedicle screw placement. The introduction of robotics may drive further advances in less invasive pediatric spinal deformity surgery. Further study is warranted.

scholarly journals Thoracolumbar instrumentation with CT-guided navigation (O-arm) in 270 consecutive patients: accuracy rates and lessons learned

2014 ◽  
Vol 36 (3) ◽  
pp. E7 ◽  
Author(s):  
Mark A. Rivkin ◽  
Steven S. Yocom
Keyword(s):  
Learning Curve ◽  
Pedicle Screw ◽  
Operating Room ◽  
Spinal Surgery ◽  
Imaging System ◽  
Screw Fixation ◽  
Pedicle Screws ◽  
Pedicle Screw Fixation ◽  
Image Guided ◽  
Accuracy Rates

Object Thoracolumbar instrumentation has experienced a dramatic increase in utilization over the last 2 decades. However, pedicle screw fixation remains a challenging undertaking, with suboptimal placement contributing to postoperative pain, neurological deficit, vascular complications, and return to the operating suite. Image-guided spinal surgery has substantially improved the accuracy rates for these procedures. However, it is not without technical challenges and a learning curve for novice operators. The authors present their experience with the O-arm intraoperative imaging system and share the lessons they learned over nearly 5 years. Methods The authors performed a retrospective chart review of 270 consecutive patients who underwent thoracolumbar pedicle screw fixation utilizing the O-arm imaging system in conjunction with StealthStation navigation between April 2009 and September 2013 at a single tertiary care center; 266 of the patients underwent CT scanning on postoperative Day 1 to evaluate hardware placement. The CT scans were interpreted prospectively by 3 neuroradiologists as part of standard work flow and retrospectively by 2 neurosurgeons and a senior resident. Pedicle screws were evaluated for breaches according to the 3-tier classification proposed by Mirza et al. Results Of 270 patients, 266 (98.5%) were included in the final analysis based on the presence of a postoperative CT scan. Overall, 1651 pedicle screws were placed in 266 patients and yielded a 5.3% breach rate; 213 thoracic and 1438 lumbosacral pedicle screws were inserted with 6.6% and 5.1% breach rates, respectively. Of the 87 suboptimally placed screws, there were 13 Grade 1, 16 Grade 2, and 12 Grade 3 misses as well as 46 anterolateral or “tip-out” perforations at L-5. Four patients (1.5%) required a return to the operating room for pedicle screw revision, 2 of whom experienced transient radicular symptoms and 2 remained asymptomatic. Interestingly, the pedicle breach rate was higher than anticipated at 13.21% for the 30 patients over the initial 6-month period with the O-arm. After certain modifications to the authors' technique, the subsequent 30 patients experienced a statistically significant decrease in breach rate at 5.6% (p = 0.014). Conclusions Image-guided spinal surgery can be a great option in the operating room and provides high pedicle screw accuracy rates. With numerous systems commercially available, it is important to develop a systematic approach regardless of the technology in question. There is a learning curve for surgeons unfamiliar with image guidance that should be recognized and appreciated when transitioning to navigation-assisted spinal surgery. In fact, the authors' experience with a large patient cohort suggests that this learning curve may be more significant than previously reported.

scholarly journals Safety and Risk Factors of Tinavi Robot-assisted Percutaneous Pedicle Screw Placement in Spinal Surgery

2021 ◽  
Author(s):  
Ren-Jie Zhang ◽  
Lu-Ping Zhou ◽  
Lai Zhang ◽  
Hua-Qing Zhang ◽  
Jian-Xiang Zhang ◽  
...  
Keyword(s):  
Risk Factors ◽  
Pedicle Screw ◽  
Spinal Surgery ◽  
Multivariate Analyses ◽  
Univariate Analysis ◽  
Pedicle Screws ◽  
Screw Placement ◽  
Insertion Point ◽  
Pedicle Screw Placement ◽  
Robot Assisted

Abstract Objective To determine the rates and risk factors of pedicle screw placement accuracy and the proximal facet joint violation (FJV) using TINAVI robot-assisted technique.Methods Patients with thoracolumbar fractures or degenerative diseases were retrospectively recruited from June 2018 and June 2020. The pedicle penetration and proximal FJV were compared in different instrumental levels to identify the safe and risk segments during insertion. Moreover, the factors were also assessed using univariate and multivariate analyses.Results A total of 72 patients with 332 pedicle screws were included in the current study. The optimal and clinically acceptable screw positions were 85.8% and 93.4%. Of the 332 screws concerning the intra-pedicular accuracy, 285 screws (85.8%) were evaluated as grade A according to the Gertzbein and Robbins scale, with the remaining 25 (7.6%), 10 (3.0%), 6 (1.8%), and 6 screws (1.8%) as grade B, C, D, and E. Moreover, in terms of the proximal FJV, 255 screws (76.8%) screws were assessed as grade 0 according to the Babu scale, with the remaining 34 (10.3%), 22 (6.6%), and 21 screws (6.3%) as grade 1, 2, and 3. Furthermore, the univariate analysis showed significantly higher rate of penetration for patients with age＜61 years old, sex of female, thoracolumbar insertion, shorter distance from skin to insertion point, and smaller facet angle. Meanwhile, the patients with the sex of female, BMI <25.9, grade I spondylolisthesis, lumbosacral insertion, longer distance from skin to insertion point, and larger facet angle had a significantly higher rate of proximal FJV. The outcomes of multivariate analyses showed that sex of male (adjusted OR 0.320, 95% CI 0.140–0.732; p =0.007), facet angle ≥45° (adjusted OR 0.266, 95% CI 0.090–0.786; p =0.017), distance from skin to insertion point ≥4.5cm (adjusted OR 0.342, 95% CI 0.134–0.868; p =0.024), and lumbosacral instrumentation (adjusted OR 0.227, 95% CI 0.091–0.566; p =0.001) were independently associated with intra-pedicular accuracy; the L5 insertion (adjusted OR 2.020, 95% CI 1.084–3.766; p =0.027) and facet angle ≥45° (adjusted OR 1.839, 95% CI 1.026–3.298; p =0.041) were independently associated with the proximal FJV.Conclusion TINAVI robot-assisted technique was associated with a high rate of pedicle screw placement and a low rate of proximal FJV. This new technique showed a safe and precise performance for pedicle screw placement in spinal surgery. Facet angle ≥45° is independently associated with both the intra-pedicular accuracy and proximal FJV.

Living Wires — Effects of Size and Coating of Gold Nanoparticles in Altering the Electrical Properties ofPhysarum polycephalumand Lettuce Seedlings

Nano LIFE ◽  
2016 ◽  
Vol 06 (01) ◽  
pp. 1650001 ◽  
Author(s):  
Nina Gizzie ◽  
Richard Mayne ◽  
Shlomo Yitzchaik ◽  
Muhamad Ikbal ◽  
Andrew Adamatzky
Keyword(s):  
Gold Nanoparticles ◽  
Electrical Properties ◽  
Electrical Resistance ◽  
Model Organism ◽  
Toxicological Effects ◽  
Biological Substrates ◽  
Microscopy Techniques ◽  
External Stimuli ◽  
A Current

The manipulation of biological substrates is becoming more popular route toward generating novel computing devices. Physarum polycephalum is used as a model organism in biocomputing because it can create “wires” for use in hybrid circuits; programmable growth by manipulation through external stimuli and the ability withstanding a current and its tolerance to hybridization with a variety of nano/microparticles. Lettuce seedlings have also had previous interest invested in them for generating plant wires, although currently there is little information as to their suitability for such applications. In this study both P. polycephalum and Lettuce seedlings were hybridized with gold nanoparticles — functionalized and unfunctionalized — to explore their uptake, toxicological effects and, crucially, any alterations in electrical properties they bestow upon the organisms. Using various microscopy techniques it was shown that P. polycephalum and lettuce seedlings are able to internalize nanoparticles and assemble them in vivo, however some toxicological effects were observed. The electrical resistance of both lettuce seedlings and P. polycephalum was found to decrease, the most significant reduction being with lettuce seedlings whose resistance reduced from 3[Formula: see text]M[Formula: see text]s to 0.5[Formula: see text]M[Formula: see text]s. We conclude that gold is a suitable nanomaterial for biohybridization specifically in creating conductive pathways for more efficient biological wires in self-growing hybrid circuitry.

Stellenwert der Navigation

2017 ◽  
Vol 01 (04) ◽  
pp. 317-334
Author(s):  
Jan-Sven Jarvers ◽  
Ulrich Spiegl ◽  
Stefan Glasmacher ◽  
Christoph Heyde ◽  
Christoph Josten
Keyword(s):  
Patient Safety ◽  
Radiation Exposure ◽  
Pedicle Screw ◽  
Spinal Surgery ◽  
Intraoperative Imaging ◽  
Intraoperative Navigation ◽  
Advantages And Disadvantages ◽  
Tumor Diseases ◽  
Intraoperative Control ◽  
Improved Technology

Abstract Importance of Navigation Navigation and intraoperative imaging have undergone an enormous development in recent years. By using intraoperative navigation, the precision of pedicle screw implantation can be increased in the sense of patient safety. Especially in the case of complex defects or tumor diseases, navigation is a decisive aid. As a result of the constantly improved technology, the requirements for reduced radiation exposure and intraoperative control can also be met. The high costs of the devices can be amortized, for example by a reduced number of revisions. This overview presents the principles of navigation in spinal surgery and the advantages and disadvantages of the different navigation procedures.

Augmented reality–assisted pedicle screw insertion: a cadaveric proof-of-concept study

2019 ◽  
Vol 31 (1) ◽  
pp. 139-146 ◽  
Author(s):  
Camilo A. Molina ◽  
Nicholas Theodore ◽  
A. Karim Ahmed ◽  
Erick M. Westbroek ◽  
Yigal Mirovsky ◽  
...  
Keyword(s):  
Augmented Reality ◽  
Pedicle Screw ◽  
User Experience ◽  
Pedicle Screws ◽  
Screw Insertion ◽  
Pedicle Screw Insertion ◽  
Insertion Method ◽  
Comparative Accuracy ◽  
Placement Accuracy ◽  
Surgical Field

OBJECTIVEAugmented reality (AR) is a novel technology that has the potential to increase the technical feasibility, accuracy, and safety of conventional manual and robotic computer-navigated pedicle insertion methods. Visual data are directly projected to the operator’s retina and overlaid onto the surgical field, thereby removing the requirement to shift attention to a remote display. The objective of this study was to assess the comparative accuracy of AR-assisted pedicle screw insertion in comparison to conventional pedicle screw insertion methods.METHODSFive cadaveric male torsos were instrumented bilaterally from T6 to L5 for a total of 120 inserted pedicle screws. Postprocedural CT scans were obtained, and screw insertion accuracy was graded by 2 independent neuroradiologists using both the Gertzbein scale (GS) and a combination of that scale and the Heary classification, referred to in this paper as the Heary-Gertzbein scale (HGS). Non-inferiority analysis was performed, comparing the accuracy to freehand, manual computer-navigated, and robotics-assisted computer-navigated insertion accuracy rates reported in the literature. User experience analysis was conducted via a user experience questionnaire filled out by operators after the procedures.RESULTSThe overall screw placement accuracy achieved with the AR system was 96.7% based on the HGS and 94.6% based on the GS. Insertion accuracy was non-inferior to accuracy reported for manual computer-navigated pedicle insertion based on both the GS and the HGS scores. When compared to accuracy reported for robotics-assisted computer-navigated insertion, accuracy achieved with the AR system was found to be non-inferior when assessed with the GS, but superior when assessed with the HGS. Last, accuracy results achieved with the AR system were found to be superior to results obtained with freehand insertion based on both the HGS and the GS scores. Accuracy results were not found to be inferior in any comparison. User experience analysis yielded “excellent” usability classification.CONCLUSIONSAR-assisted pedicle screw insertion is a technically feasible and accurate insertion method.

scholarly journals Novel free-hand T1 pedicle screw method: Review of 44 consecutive cases

2014 ◽  
Vol 05 (04) ◽  
pp. 349-354 ◽  
Author(s):  
Mark A. Rivkin ◽  
Jessica F. Okun ◽  
Steven S. Yocom
Keyword(s):  
Pedicle Screw ◽  
Thoracic Spine ◽  
Pedicle Screws ◽  
High Rate ◽  
Imaging Modalities ◽  
Neurological Deficits ◽  
Upper Thoracic Spine ◽  
Starting Point ◽  
Grade 3 ◽  
Upper Thoracic

ABSTRACT Summary of Background Data: Multilevel posterior cervical instrumented fusions are becoming more prevalent in current practice. Biomechanical characteristics of the cervicothoracic junction may necessitate extending the construct to upper thoracic segments. However, fixation in upper thoracic spine can be technically demanding owing to transitional anatomy while suboptimal placement facilitates vascular and neurologic complications. Thoracic instrumentation methods include free-hand, fluoroscopic guidance, and CT-based image guidance. However, fluoroscopy of upper thoracic spine is challenging secondary to vertebral geometry and patient positioning, while image-guided systems present substantial financial commitment and are not readily available at most centers. Additionally, imaging modalities increase radiation exposure to the patient and surgeon while potentially lengthening surgical time. Materials and Methods: Retrospective review of 44 consecutive patients undergoing a cervicothoracic fusion by a single surgeon using the novel free-hand T1 pedicle screw technique between June 2009 and November 2012. A starting point medial and cephalad to classic entry as well as new trajectory were utilized. No imaging modalities were employed during screw insertion. Postoperative CT scans were obtained on day 1. Screw accuracy was independently evaluated according to the Heary classification. Results: In total, 87 pedicle screws placed were at T1. Grade 1 placement occurred in 72 (82.8%) screws, Grade 2 in 4 (4.6%) screws and Grade 3 in 9 (10.3%) screws. All Grade 2 and 3 breaches were <2 mm except one Grade 3 screw breaching 2-4 mm laterally. Only two screws (2.3%) were noted to be Grade 4, both breaching medially by less than 2 mm. No new neurological deficits or returns to operating room took place postoperatively. Conclusions: This modification of the traditional starting point and trajectory at T1 is safe and effective. It attenuates additional bone removal or imaging modalities while maintaining a high rate of successful screw placement compared to historical controls.

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