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Zhou LP, Zhang RJ, Zhang HQ, Jiang ZF, Shang J, Shen CL. Effect of High-Riding Vertebral Artery on the Accuracy and Safety of C2 Pedicle Screw Placement in Basilar Invagination and Related Risk Factors. Global Spine J 2024; 14:458-469. [PMID: 35719094 PMCID: PMC10802529 DOI: 10.1177/21925682221110180] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
STUDY DESIGN Retrospective cohort study. OBJECTIVE To investigate the effect of HRVA on the intrapedicular accuracy of C2PS placement through the freehand method in patients with BI and analyse the possible risk factors for C2PS malpositioning. METHOD A total of 91 consecutive patients with BI who received 174 unilateral C2PS placements through the freehand method were retrospectively included. The unilateral pedicles were assigned to the HRVA and non-HRVA groups. The primary outcome was the intrapedicular accuracy of C2PS placement in accordance with the Gertzbein-Robbins scale. Moreover, the risk factors that possibly affected intrapedicular accuracy were assessed. RESULTS The rate of intrapedicular accuracy in C2PS placement in patients with BI was 23.6%. Results showed that the non-HRVA group had remarkably higher rates of optimal and clinically acceptable C2PS placement than the HRVA group. Nevertheless, the HRVA group exhibited similar results for grade B classification as the non-HRVA group. Moreover, in the HRVA and non-HRVA groups, the most common direction of screw deviations was the lateral direction. Furthermore, the multivariate analyses showed that the obliquity of the lateral atlantoaxial joint in the sagittal plane ≥15°, and that in the coronal plane ≥ 20°, isthmus height < 4.3 mm, and distance from the skin to the spinous process ≥ 2.8 cm independently contributed to a high rate of screw malpositioning in BI patients. CONCLUSION The presence of HRVA in BI patients contributed to the high rate of malpositioning in C2PS placement via the freehand method. However, the rates of intrapedicular accuracy in patients with BI with and without HRVA were considerably low.
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Affiliation(s)
- Lu-Ping Zhou
- Department of Orthopedics, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Ren-Jie Zhang
- Department of Orthopedics, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Hua-Qing Zhang
- Department of Orthopedics, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhen-Fei Jiang
- Department of Orthopedics, The First Affiliated Hospital of University of Science and Technology of China, Hefei, China
| | - Jin Shang
- Department of Radiology, The First Affiliated Hospital of University of Science and Technology of China, Hefei, China
| | - Cai-Liang Shen
- Department of Orthopedics, The First Affiliated Hospital of Anhui Medical University, Hefei, China
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Varghese JE, Rabi S, Joseph V, Jeyaseelan L, Prithishkumar IJ. Morphometric Analysis of the Neural Arch of C2 Vertebra in Indian Population. Neurol India 2024; 72:334-339. [PMID: 38691478 DOI: 10.4103/ni.ni_1033_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 04/09/2023] [Indexed: 05/03/2024]
Abstract
BACKGROUND AND OBJECTIVE The most common injuries to upper cervical spine are fractures of the second cervical vertebrae. The study aims to evaluate the morphometry of the neural arch of the second cervical vertebrae in the South Indian population. MATERIALS AND METHODS Sixty-three second cervical vertebrae of undetermined gender and age without any gross defect were used for the study. The dimensions of neural arch, including superior articular facet, inferior articular facet, pediculoisthmic component, lamina, spinous process, foramen transversarium, and vertebral foramen, were measured by two independent observers using digital vernier caliper accurate to 0.1 mm and the data was analyzed. Descriptive statistics were obtained for the variables. Paired t-test was done to compare the measurements between right and left sides. RESULTS There was no statistical difference between the right and left sides of the dimensions of superior articular facets, foramen transversarium, and the transverse diameter of inferior articular facet. The anteroposterior diameter of the inferior articular facets was more on the right side (P = 0.009). The width of the pediculoisthmic component in both the superior and inferior aspects was found to be less on the right side than that of the left (P = 0.006 and P = 0.031, respectively). The thickness in the middle one-third of laminae was optimum for bilateral safe screw insertion (≥4.0 mm) in 77% specimens. CONCLUSION In summary, measurements of the transverse diameter of superior articular facet and thickness of lamina differed significantly from those reported in literature. This should be kept in mind while doing neurosurgery procedures in the Indian population.
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Affiliation(s)
- Jija E Varghese
- Department of Anatomy, Christian Medical College, Vellore, Tamil Nadu, India
| | - Suganthy Rabi
- Department of Anatomy, Christian Medical College, Vellore, Tamil Nadu, India
| | - Vivek Joseph
- Department of Neurosurgery, Christian Medical College, Vellore, Tamil Nadu, India
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Rosinski A, Balcescu C, Singleton I, Mittal A, Odeh K, Ungurean V, Leasure J, Kondrashov D. C1-C2 Facet Joint Penetration by C2 Pedicle Screws: Influence of Local Anatomy, Bone Mineral Density, and Screw Length. Int J Spine Surg 2023; 17:76-85. [PMID: 36414377 PMCID: PMC10025835 DOI: 10.14444/8386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND A challenge of C2 pedicle screw placement is to avoid penetration into the C1-C2 facet joint, as this may alter normal biomechanics and accelerate joint degeneration. Our objective was to clarify how local anatomy and surgical technique may relate to C2 pedicle screw penetration into the C1-C2 facet joint. METHODS C2 pedicle screws were inserted using a fluoroscopically assisted freehand technique. Independent fellowship-trained spine surgeons blindly reviewed intraoperative fluoroscopic and postoperative computed tomography (CT) images for evidence of facet joint penetration (FJP). C2 pedicle morphometry, the sagittal angle of the facet joint, axial and sagittal pedicle screw angles, and screw length were measured on the relevant CT images. RESULTS A total of 34 patients fulfilled the study criteria, and a total of 68 C2 pedicle screws were placed. Eight screws (16%) penetrated the C1-C2 facet joint. The mean sagittal angle of the C1-C2 facet joint was significantly lower in the FJP group compared with the non-FJP group. The mean sagittal angle of the screws was significantly higher in the FJP group compared with the non-FJP group. The mean screw length was significantly greater for screws causing FJP compared with the non-FJP group. The mean axial screw angle was significantly lower in the FJP group compared with the non-FJP group. Pedicle width, length, height, and transverse angle were not significantly associated with FJP. Independent reviewers were able to identify FJP on intraoperative fluoroscopic imaging in 2 out of 8 cases. CONCLUSION Lower sagittal angle of the facet joint, higher sagittal angle of the pedicle screw, and screw length >24 mm are associated with higher risk of C1-C2 FJP. When placing C2 pedicle screws under these conditions, caution should be taken to avoid FJP. CLINICAL RELEVANCE Several anatomical and technical factors may increase the risk of C1-C2 FJP during placement of C2 pedicle screws using a fluoroscopically assisted freehand technique, underscoring the importance of preoperative planning and limiting screw length. LEVEL OF EVIDENCE: 3
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Affiliation(s)
- Alexander Rosinski
- St. Mary's Medical Center, San Francisco Orthopaedic Residency Program, San Francisco, CA, USA
| | - Cristian Balcescu
- St. Mary's Medical Center, San Francisco Orthopaedic Residency Program, San Francisco, CA, USA
| | - Ian Singleton
- St. Mary's Medical Center, San Francisco Orthopaedic Residency Program, San Francisco, CA, USA
| | - Ashish Mittal
- St. Mary's Medical Center, San Francisco Orthopaedic Residency Program, San Francisco, CA, USA
| | - Khalid Odeh
- St. Mary's Medical Center, San Francisco Orthopaedic Residency Program, San Francisco, CA, USA
| | | | | | - Dimitriy Kondrashov
- St. Mary's Medical Center, San Francisco Orthopaedic Residency Program, San Francisco, CA, USA
- San Francisco Spine Surgeons, San Francisco, CA, USA
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A comprehensive analysis and literature review of vertebral artery variation in craniovertebral junction using three-dimensional computed tomography angiography. Neuroradiology 2023; 65:215-223. [PMID: 36394613 DOI: 10.1007/s00234-022-03082-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 11/02/2022] [Indexed: 11/19/2022]
Abstract
PURPOSE To describe vertebral artery (VA) variation in patients with or without osseous anomalies at congenital craniovertebral junction (CVJ). METHODS In the present study, we retrospectively analyzed 258 patients with VA variation who underwent three-dimensional computed tomography angiography (3D CTA) in our hospital from March 2017 to October 2019. RESULTS Among 258 patients, 180 were accompanied by skeleton structural malformation, including 105 cases of occipital ossification of the atlas, 8 cases of the bipartite atlas, 7 cases of hypoplasia of the posterior arch of the atlas, 45 cases of C2/3 congenital fusion, 2 cases of C2/3/4 congenital fusion, and 13 cases of congenital os odontoid. VA variation was divided into type A (VA variation in the CVJ area without osseous anomalies) and type B (VA variation in the CVJ area with osseous anomalies). There are totally 10 subtypes, including type A1 (atlas occipitalization with VA entrance approach close to middle line, 20.2%); type A2 (atlas occipitalization with VA entrance approach far from middle line, 30.2%); type A3 (first intersegmental VA in C1-C2, 1.9%); type A4 (fenestration of the VA, 2.3%); type A5 (VA bulging type, 6.6%); type A6 (VA exposures with the absence of the posterior atlas arch, 2.3%); type A7 (C2 inner wall type, 0.4%); type A8 (single vertebral artery, 2.3%); type B1 (posterior ponticuli, 2.7%); and type B2 (high-riding VA, 31.4%). CONCLUSION This study is expected to take the lead in the most comprehensive classification of VA variation.
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Malikov A, Secen AE, Ocal O, Divanlioglu D, Belen AD, Dalgic A. Accuracy of Axis Drill Guides in the Cases of Atlantoaxial Instabilities Associated With High-Riding Vertebral Arteries, Narrow Pedicles, and Complex Deformities: Comparison of 3 Fixation Methods. World Neurosurg 2022; 168:e336-e343. [DOI: 10.1016/j.wneu.2022.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 10/03/2022] [Indexed: 12/15/2022]
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Zhou LP, Zhang RJ, Jiang ZF, Tao EX, Shang J, Shen CL. Ideal entry point and trajectory for C2 pedicle screw placement in basilar invagination patients with high-riding vertebral artery based on 3D computed tomography. Spine J 2022; 22:1281-1291. [PMID: 35508287 DOI: 10.1016/j.spinee.2022.04.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 04/10/2022] [Accepted: 04/26/2022] [Indexed: 02/03/2023]
Abstract
BACKGROUND C2 pedicle screw placement in patients with basilar invagination (BI) is fraught with risks because of a high incidence of anatomical variations and high-riding vertebral artery (HRVA). However, no study can be found in the literature that attempted to identify the ideal entry point and trajectory through the C2 pedicle in BI patients with HRVA. PURPOSE To investigate the parameters of ideal entry point and trajectory for C2 pedicle screw placement in BI patients with HRVA and compare them with those in BI patients without HRVA and patients without BI as control. These parameters would serve as a guide to pedicle screw placement. STUDY DESIGN A retrospective comparative study. PATIENT SAMPLE A total of 396 patients (198 consecutive BI patients and 198 matched patients without BI as control) and 792 unilateral pedicles from April 2017 to October 2021 at two medical centers were included. OUTCOME MEASURES The insertion parameters of mediolateral angle, surface distance, cephalad angle, and vertical distance from the superior border of the lamina were the primary outcome measures for the reference of C2 pedicle screw placement. Furthermore, factors that affect the primary insertion parameters were assessed via multiple linear regression analyses. METHOD According to the diagnosis of BI and HRVA, the unilateral pedicles were assigned into HRVA of BI, non-HRVA of BI, HRVA of control, and non-HRVA of control groups. Subgroup analyses based on Goel types A and B were also performed. Moreover, vertebral artery (VA) anomalies that might result in potentially serious complications were identified and systematically compared. RESULTS The measurements of insertion parameters in BI patients with HRVA indicated a mean mediolateral angle of 27.42°, a mean cephalad angle of 43.02°, a mean surface distance of 9.74 mm, and a mean vertical distance from the superior border of the lamina of 3.85 mm. Compared with that in BI patients without HRVA, the measurements suggested that the entry point in BI patients with HRVA should be shifted upward by 0.38 mm and the trajectory should be angled cephalad by 6.05° and medially by 4.78°. In the control group, changes in the insertion parameters between HRVA and non-HRVA showed a similar trend to the BI group. Multiple linear regression showed that mediolateral angle was significantly associated with the male gender (B=-0.930, p=.017) and the diagnoses of HRVA (B=6.964, p<.001), Goel type A (B=-1.656, p=.003), and Goel type B (B=0.981, p=.030). Moreover, cephalad angle was significantly associated with the length of lateral mass (B=-0.319, p=.001) and the diagnoses of HRVA (B=3.254, p<.001) and Goel type A (B=6.924, p<.001). The VA anomalies were significantly higher in the BI group than in the control group. CONCLUSIONS The insertion parameters of the ideal entry point and trajectory for C2 screw placement in BI patients with HRVA were remarkably different from those of non-HRVA of BI, HRVA of control, and non-HRVA of control cohorts. Preoperative 3D computed tomography (CT) and CT angiography are highly recommended in such patients to improve intraoperative safety and reduce postoperative complications.
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Affiliation(s)
- Lu-Ping Zhou
- Department of Orthopedics, the First Affiliated Hospital of Anhui Medical University, 210 Jixi Rd, Hefei, Anhui 230022, China
| | - Ren-Jie Zhang
- Department of Orthopedics, the First Affiliated Hospital of Anhui Medical University, 210 Jixi Rd, Hefei, Anhui 230022, China
| | - Zhen-Fei Jiang
- Department of Orthopedics, the First Affiliated Hospital of University of Science and Technology of China, 17 Lujiang Rd, Hefei, Anhui 230001, China
| | - Er-Xu Tao
- Department of Orthopedics, the First Affiliated Hospital of Anhui Medical University, 210 Jixi Rd, Hefei, Anhui 230022, China
| | - Jin Shang
- Department of radiology, the First Affiliated Hospital of University of Science and Technology of China, 107 Huanhudong Rd, Hefei, Anhui 230031, China
| | - Cai-Liang Shen
- Department of Orthopedics, the First Affiliated Hospital of Anhui Medical University, 210 Jixi Rd, Hefei, Anhui 230022, China.
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Prevalence of Vertebral artery anomaly in upper cervical and its surgical implications: a systematic review. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2021; 30:3607-3613. [PMID: 34601625 DOI: 10.1007/s00586-021-07015-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 08/23/2021] [Accepted: 09/27/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND The presence vertebral artery (VA) abnormalities in the upper cervical may be a potential cause of catastrophic complication in the posterior approach of the upper cervical spine surgery. The aim of this study was to demonstrate the real incidence of the V3 segment anomaly in patients who need upper cervical surgery, and tried to find out the risk factors of V3 segment anomaly to evaluate the necessary of computed tomographic angiography (CTA) for upper cervical surgery. METHOD This systematic review was conducted following the preferred reporting items for systematic reviews and meta-Analyses (PRISMA). Retrospective studies and reports of case series involving human subjects with data on anomalies of vertebral artery in upper cervical spine were included. Data on the prevalence of persistent first intersegmental artery (PIA), fenestration of the VA (FA), posterior inferior cerebellar artery (PICA) were extracted. RESULTS A total of 16 articles involving 5927 subjects met the inclusion criteria. The total incidence of V3 segment anomaly in the patients with bony abnormalities was 25.9% (74/286): PIA was 17.5%, FA was 6.6% and PICA was 1.8%. The total incidence of V3 segment anomaly in the patients without bony abnormalities was 2.7% (152/5671): PIA was 1.76%, FA was 0.4% and PICA was 0.5%. The total incidence of V3 segment anomaly in Asian population without bony abnormalities was 5.8%, while in European and American population was 0.8 and 0.6%, respectively. CONCLUSION Patients with bone abnormalities are high risk factor for VA abnormalities, CTA is of paramount importance to evaluate the variant VA anatomy. However, regarding to the low incidence of V3 variation in normal population, we do not recommend preoperative CT angiography as mandatory part of preoperative.
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Karagoz Guzey F, Gulec I, Eren B. Suitability of the Subaxial Cervical Laminae for Laminar Screws in the Pediatric Population: A Radiologic Anatomical Study. Pediatr Neurosurg 2021; 56:10-16. [PMID: 33540411 DOI: 10.1159/000513371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 11/23/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION The laminar screw method was popularized during recent years. Since no data exist in the literature on its suitability for subaxial levels in the pediatric population, a radiologic anatomical study was planned to evaluate the suitability of the laminae for laminar screws in children. METHODS The laminar thicknesses from C3 to C7 were measured in axial sections in 120 pediatric patients using computed tomography. The patients were divided into 3 age-groups: ages 4-6, 7-9, and 10-12. Each age-group consisted of 20 boys and 20 girls. The suitability of the laminae was evaluated for 3.5-mm-thick commercially available screws and also for the 3-mm screws that could be produced in the future. If the height of the base of the spinous process is ≥ 9 mm, the segment was accepted as suitable for the bilateral screw, and ≥5 mm is for the unilateral screw. Additionally, laminar thickness and length were measured for possible short screws longer than 15 mm in the laminae that were distally thin but proximally thick. RESULTS The C4 and C5 levels had the thinnest (2.77 ± 0.6 mm and 2.81 ± 0.6 mm, respectively) and C7 had the thickest laminae (4.66 ± 0.6 mm) in all age-groups. No significant differences were found between boys and girls and right and left laminae. According to the age-groups, an increase in laminar thickness was possible by growing, but only C7 laminae thickness was statistically different between 10-12 and 4-6 age-groups (p < 0.001). The last rate of the suitability was 9.1% for the 3.5-mm-thick screws and 13.75% for the 3-mm-thick screws after deletion of the bilateral insertion due to the short base of the spinous process and adding the possible short screws in the distally thin but proximally thick laminae. The rates increased with age, but the only statistically significant difference was found between 4-6- and 10-12-year-old age-groups (p < 0.001). CONCLUSIONS Laminar screws may be suitable for some levels of C7, C6, and C3 even in the young pediatric population. The use of thinner screws (3 mm) may increase the suitability rate. Therefore, laminar screw choice may be considered as a salvage method in pediatric patients, and all laminae may be evaluated individually for suitability. This study did not evaluate the safety and efficacy of the method in children, and these issues must be studied further.
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Affiliation(s)
- Feyza Karagoz Guzey
- Department of Neurosurgery, Health Sciences University Turkey, Bagcilar Training and Research Hospital, Istanbul, Turkey,
| | - Ilker Gulec
- Department of Neurosurgery, Health Sciences University Turkey, Bagcilar Training and Research Hospital, Istanbul, Turkey
| | - Burak Eren
- Department of Neurosurgery, Health Sciences University Turkey, Bagcilar Training and Research Hospital, Istanbul, Turkey
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Guo Q, Zhou X, Guo X, Han Z, Chen F, Zhu J, Lu X, Ni B. C2 partial transpedicular screw technique for atlantoaxial dislocation with high-riding vertebral artery: A technique note with case series. Clin Neurol Neurosurg 2020; 200:106403. [PMID: 33338827 DOI: 10.1016/j.clineuro.2020.106403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Although the C2 pedicle screw (C2PS) is currently the most biomechanically robust option for C2 fixation, the high-riding vertebral artery (HRVA) precludes safe C2PS placement. However, unintentional partial C2 pedicle perforation and vertebral foramen violation due to C2PS placement without neurovascular complications occurred frequently in clinic. Therefore, we have attempted to apply C2 partial transpedicular screw (C2PTS) in patients with HRVA with satisfactory preliminary outcomes. The aim of the present study is to introduce the C2PTS technique and report the preliminary radiological and clinical outcomes of application of C2PTS. PATIENTS AND METHODS The data of 15 patients with atlantoaxial dislocation underwent atlantoaxial arthrodesis with posterior screw-rod construct were retrospectively reviewed. All patients had unilateral or bilateral HRVA that precluded safe C2PS placement and C2PTS was used as an alternative. In this technique, a Penfield dissector was used to properly mobilize the HRVA inferiorly to preclude vertebral artery injury and pave the way for C2PTS placement. The C2PTS travelled under the superior border of the isthmus and toward the ipsilateral atlantoaxial articulation. The implant position and atlantoaxial reduction were evaluated using computed tomography (CT) scans and vertebral artery (VA) was assessed using CT angiography postoperatively. RESULTS Satisfactory C2PTS placement and atlantoaxial reduction were achieved in all patients. Postoperatively, no vertebral artery injury and implant failure were observed, and bone fusion was achieved in all the patients. Additionally, there were no VA occlusion or stenosis due to screws demonstrated on VA CT angiography. CONCLUSION C2PTS can achieve three-column fixation of axis and is an efficient alternative to C2PS which is prohibited due to HRVA; also, gently mobilizing the HRVA inferiorly is mandatory to prevent vertebral artery injury during C2PTS placement.
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Affiliation(s)
- Qunfeng Guo
- From the Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, Shanghai, People's Republic of China
| | - Xin Zhou
- From the Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, Shanghai, People's Republic of China
| | - Xiang Guo
- From the Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, Shanghai, People's Republic of China
| | - Zhao Han
- From the Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, Shanghai, People's Republic of China
| | - Fei Chen
- From the Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, Shanghai, People's Republic of China
| | - Jingyu Zhu
- From the Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, Shanghai, People's Republic of China
| | - Xuhua Lu
- From the Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, Shanghai, People's Republic of China
| | - Bin Ni
- From the Department of Orthopedics, Changzheng Hospital, The Second Military Medical University, Shanghai, People's Republic of China.
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Pavlov O, Mirchev N, Behr R. A possible novel technique for intraoperative imaging of the vertebral artery during arthrodesis of the upper cervical spine. Med Hypotheses 2020; 140:109641. [PMID: 32105970 DOI: 10.1016/j.mehy.2020.109641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/18/2020] [Accepted: 02/20/2020] [Indexed: 10/25/2022]
Abstract
In elderly, the fractures in C1-C2 are a common entity. Poor bone quality and wide range of motion hamper the natural bone fusion, thus making surgery often the only possible way to deal with the underlying pathology. The proximity to important neurovascular structures represents the stabilization in this segment a challenge to the surgical team. There are two major techniques, which are used to achieve a dorsal fusion in the C1-C2 Segment: Goel/Harms and Magerl techniques. The reported risk for damaging the vertebral artery in both techniques lies between 8% and 9,5% using a C-Arm. In Goel/Harms technique lateral mass screws in C1 and pedicle screws in C2 are placed. A transarticular screw is placed on both sides C1-C2 in Magerl technique in order to achieve stabilization of the C1-C2 Segment. By using the new navigational methods for a better imaging of the bony structures (O-Arm), this risk could be reduced further down. The risk for injury of the vertebral artery using the O-Arm navigation depends on the pathology, which is operated, ranging from 0, 3% to 2%. A further problem represents the anatomical variations of the vertebral artery, of which the high-riding vertebral artery being the most important one, reported between 10 and 14,5% of the cases according to the literature review. The novel technique for intraoperative imaging of the vertebral artery represents a fusion between an intraoperative O-Arm and intraoperative application of contrast, thus intraoperatively seeing the exact way of the vertebral artery. Also, after the insertion of the screws, a second CT scan with the O-Arm could be performed, yet again with contrast, to see whether the perfusion of both vertebral arteries is preserved. The significance of this method could bring the injuries of the vertebral artery to 0% independently on the technique, which has been used. This method could be used not only for craniocervical stabilization but also for removal of complex tumors in craniocervical junctions, whereas the vertebral artery is encompassed.
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Affiliation(s)
- O Pavlov
- Klinikum Fulda, Pacellialle 2, 36043 Fulda, Hessen, Germany.
| | - N Mirchev
- Klinikum Fulda, Pacellialle 2, 36043 Fulda, Hessen, Germany
| | - R Behr
- Klinikum Fulda, Pacellialle 2, 36043 Fulda, Hessen, Germany
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Zong R, Li T, Lu L, Qiao G, Yu X. Posterior C2 Fixation Using Trans-C2 Inferior Articular Process Screws: A Case Series and Technical Note. World Neurosurg 2018; 121:e70-e76. [PMID: 30213673 DOI: 10.1016/j.wneu.2018.09.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 08/30/2018] [Accepted: 09/02/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE Upper cervical fixation with C2 pedicle screw insertion may predispose patients to vertebral artery injury, in particular, patients with craniovertebral junction anomalies. The aim of this study was to describe an alternative technique with trans-C2 inferior articular process screw (C2IAPS) insertion for rigid C2 fixation, which can be used to anchor the C2 vertebra for upper cervical fixation. METHODS Records of 19 patients who underwent posterior atlantoaxial fixation using C2IAPS combined with C1 lateral mass screw were retrospectively reviewed. Efficacy was assessed by postoperative imaging and Japanese Orthopaedic Association scores. RESULTS There were 22 C2IAPSs successfully implanted (3 on both sides and 16 on 1 side). With the exception of 2 screws that had intruded into the outlet of the intervertebral foramen, all screws were safely implanted. Average Japanese Orthopaedic Association scores improved from 11.8 ± 1.9 preoperatively to 15.3 ± 1.3 postoperatively. Bony fusion rate was 100%. CONCLUSIONS For patients who are not eligible for C2 pedicle screw fixation, C2IAPS fixation can be considered as an alternative technique for upper cervical fixation of C2.
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Affiliation(s)
- Rui Zong
- Department of Neurosurgery, General Hospital of People's Liberation Army, Beijing, China
| | - Teng Li
- Department of Neurosurgery, General Hospital of People's Liberation Army, Beijing, China
| | - Lenian Lu
- Department of Neurosurgery, The First People's Hospital of Shunde, Foshan City, Guangdong Province, China
| | - Guangyu Qiao
- Department of Neurosurgery, General Hospital of People's Liberation Army, Beijing, China
| | - Xinguang Yu
- Department of Neurosurgery, General Hospital of People's Liberation Army, Beijing, China.
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Gu J, Lei W, Xin Z, Wu Y, Peng L, Li Z, Feng Z, Zhao M, Qi S, Lu Y. Occiput-axis crossing translaminar screw fixation technique using offset connectors: An in vitro biomechanical study. Clin Neurol Neurosurg 2018; 169:49-54. [PMID: 29627641 DOI: 10.1016/j.clineuro.2018.04.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 03/28/2018] [Accepted: 04/01/2018] [Indexed: 10/17/2022]
Abstract
OBJECTIVE Fixation with the axis vertebra (C2) using pedicle screws is commonly used to treat an unstable occipitocervical junction; however, it is accompanied by a risk of vertebral artery injury. The occiput-C2 (OC2) crossing translaminar screw fixation technique may avoid this risk, but rod implantation is difficult. Offset connectors can help facilitate this construct. This study aimed to evaluate the stability of a technique for OC2 crossing translaminar screw fixation using offset connectors (C2LAM + OF) in comparison with other methods. PATIENTS AND METHODS Six fresh-frozen human cadaveric occipital-cervical spines were tested intact under flexion, extension, lateral bending, and axial rotation. These were then made into a type II odontoid fracture model, instrumented with an occipital plate, and tested in the following modes: C2 bilateral pedicle screws (C2P), a single C2 pedicle screw and bilateral C3 lateral mass screws (C2P + C3M), C2 crossing translaminar screws (C2LAM), and C2LAM + OF. The OC2 range of motion (ROM) for each construct was obtained and compared using a repeated-measures analysis. RESULTS The ROM of the C2LAM + OF construct was found not to be significantly different from that of the C2P and C2P + C3M fixations in every direction (p > 0.05). However, the C2LAM + OF construct was superior to the C2LAM construct in axial rotation (p < 0.05). CONCLUSIONS OC2 crossing translaminar screw fixation using offset connectors offers similar stability to C2 pedicle screw fixation and is an effective alternative method for treating an unstable occipitocervical junction.
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Affiliation(s)
- Jiyong Gu
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, PR China; Department of Neurosurgery, Jiangmen Central Hospital, Jiangmen City, Guangdong Province, PR China
| | - Weiwei Lei
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, PR China
| | - Zong Xin
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, PR China
| | - Yi Wu
- Department of Neurosurgery, Jiangmen Central Hospital, Jiangmen City, Guangdong Province, PR China
| | - Lin Peng
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, PR China
| | - Zhibin Li
- Department of Neurosurgery, Jiangmen Central Hospital, Jiangmen City, Guangdong Province, PR China
| | - Zize Feng
- Department of Neurosurgery, Jiangmen Central Hospital, Jiangmen City, Guangdong Province, PR China
| | - Minchan Zhao
- Network Information Management Center, Jiangmen Central Hospital, Jiangmen City, Guangdong Province, PR China
| | - Songtao Qi
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, PR China.
| | - Yuntao Lu
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, PR China.
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Patkar SV. New entry point for C2 screw, in posterior C1-C2 fixation (Goel-Harm's technique) significantly reducing the possibility of vertebral artery injury. Neurol Res 2017; 38:93-7. [PMID: 27118605 DOI: 10.1080/01616412.2015.1105582] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To reduce the chance of vertebral artery injury in posterior C1 lateral mass and C2 pedicle/pars screw-rod fixation (Goel-Harms technique ). METHOD 49 patients, 30 males and 19 females, 12years - 82 years, underwent posterior C1-C2 fixation from February 2007 till June2013. A new entry point for the posterior C2 screw, 3mm below the midpoint of the C1-C2 joint which is directed medially and downwards into the C2 body , probably avoids the vertebral artery. As the screw now bypasses the pedicle/ pars , the chance of injuring the vertebral artery is probably reduced. RESULTS No case of intra-operative vertebral artery injury. CONCLUSION The new technique of C2 screw fixation allows rigid immobilization of the C1-C2 joint without significant risk of vertebral artery injury.
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Affiliation(s)
- Sushil Vasant Patkar
- a Poona Hospital & Research Centre , Bharati Vidyapeeth Medical College , Pune , India
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Prevalence of High-Riding Vertebral Artery and Morphometry of C2 Pedicles Using a Novel Computed Tomography Reconstruction Technique. Asian Spine J 2016; 10:1141-1148. [PMID: 27994792 PMCID: PMC5165006 DOI: 10.4184/asj.2016.10.6.1141] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 04/23/2016] [Accepted: 05/08/2016] [Indexed: 11/22/2022] Open
Abstract
Study Design Cross-sectional, matched-pair comparative study. Purpose To determine whether a thin-sliced pedicular-oriented computed tomography (TPCT) scan reconstructed from an existing conventional computed tomography (CCT) scan is more accurate for identifying vertebral artery groove (VAG) anomalies than CCT. Overview of Literature Posterior atlantoaxial transarticular screw fixation and C2 pedicle screws can cause vertebral artery (VA) injury. Two anatomic variations of VAG anomalies are associated with VA injury: a high-riding VA (HRVA) and a narrow pedicle of the C2 vertebra. CCT scan is a reliable method used to evaluate VAG anomalies; however, its accuracy level remains debatable. Literature comparing the prevalence of C2 VAG anomalies between CCT and TPCT is limited. Methods A total of 200 computed tomography scans of the upper cervical spine obtained between January 2008 and December 2011 were evaluated for C2 VAG anomalies (HRVA and narrow pedicular width) using CCT and TPCT. The prevalence of C2 VAG anomalies was compared using these two different measurement methods via a McNemar's test. Results Of the 200 patients studied, 23 HRVA (6.01%; 95% confidence interval [CI], 3.61%–8.39%) were detected with CCT, whereas 66 HRVA (16.54%; 95% CI, 12.85%–20.23%) were detected with TPCT (p<0.001). Sixty-two narrow pedicles (15.58%; 95% CI, 11.99%–19.15%) were detected with CCT, whereas 90 narrow pedicles (22.83%; 95% CI, 18.58%–26.87%) were detected with TPCT (p<0.001). Conclusions VAG anomalies are commonly observed. A preoperative evaluation using TPCT reconstructed from an existing CCT revealed a significantly higher prevalence of C2 VAG anomalies than did CCT and showed comparable prevalence to previously published studies using more sophisticated and higher risk techniques. Therefore, we propose TPCT as an alternative preoperative evaluation for C2 screw placement and trajectory planning.
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Jagetia A, Mewda T, Bishnoi I, Bhutte M, Singh H, Srivastava AK, Singh D. Understanding the Course of Vertebral Artery at Craniovertebral Junction in Occipital Assimilation of Atlas: Made Simplified Using Conventional Angiography. J Neurol Surg B Skull Base 2016; 78:173-178. [PMID: 28321382 DOI: 10.1055/s-0036-1594240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 09/25/2016] [Indexed: 10/20/2022] Open
Abstract
Introduction Preoperative assessment of vertebral artery (VA) is important to avoid its injury during surgery at craniovertebral junction (CVJ). The main concern is the course of third segment of VA (V3) while performing instrumentation at CVJ, that is, segment of VA from its course through transverse foramen of C2 to its course along the posterior arch of C1. This segment of VA includes its passage through C1 transverse foramen as well. This observational study was done to analyze the course, curvature, and termination of VA in patients with occipital assimilation of atlas at CVJ, a complex congenital anomaly, and compared with the normal course for better understanding especially by young neurosurgeons and spine surgeons. Materials and Method This is an observational study that included patients with occipitalized C1 with or without associated anomalies. Out of 30 patients of CVJ anomalies, 16 patients had occipitalized atlas. Digital subtraction angiography was done in all cases. It was done by selectively catheterizing the VA using standard Seldinger's technique and both anteroposterior and lateral projections were taken. Results The course of VA was not identical on either side in any individual. It was lengthened and tortuous in all patients. Different types of anomalous course were encountered like bypassing transverse foramen of C1, close relation with C1-2 facet joints, variable course along the posterior arch of C1, abnormal termination and fenestration of VA. Conclusion Craniovertebral junction anomalies are not only bony or neural, but are vascular too. Complex CVJ anomalies are associated with higher incidence of anomalous course of the VA, an important surgical consideration.
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Affiliation(s)
- Anita Jagetia
- Department of Neurosurgery, GIPMER and associated Maulana Azad Medical College, Delhi, India
| | - Tushit Mewda
- Department of Neurosurgery, GIPMER and associated Maulana Azad Medical College, Delhi, India
| | - Ishu Bishnoi
- Department of Neurosurgery, GIPMER and associated Maulana Azad Medical College, Delhi, India
| | - Manoj Bhutte
- Department of Neurosurgery, GIPMER and associated Maulana Azad Medical College, Delhi, India
| | - Hukum Singh
- Department of Neurosurgery, GIPMER and associated Maulana Azad Medical College, Delhi, India
| | - A K Srivastava
- Department of Neurosurgery, GIPMER and associated Maulana Azad Medical College, Delhi, India
| | - Daljit Singh
- Department of Neurosurgery, GIPMER and associated Maulana Azad Medical College, Delhi, India
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Tubbs RS, Granger A, Fisahn C, Loukas M, Moisi M, Iwanaga J, Paulson D, Jeyamohan S, Chapman JR, Oskouian RJ. The Vertebral Artery Cave at C2: Anatomic Study with Application to C2 Pedicle Screw Placement. World Neurosurg 2016; 94:368-374. [DOI: 10.1016/j.wneu.2016.07.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/11/2016] [Accepted: 07/11/2016] [Indexed: 10/21/2022]
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Maki S, Koda M, Iijima Y, Furuya T, Inada T, Kamiya K, Ota M, Saito J, Okawa A, Takahashi K, Yamazaki M. Medially-shifted rather than high-riding vertebral arteries preclude safe pedicle screw insertion. J Clin Neurosci 2016; 29:169-72. [DOI: 10.1016/j.jocn.2015.11.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 11/04/2015] [Indexed: 10/22/2022]
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18
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Le Pape S, Gauthe R, Latrobe C, Cantogrel P, Proust F, Leroux J, Ould-Slimane M. [Are C2 pedicles always screwable? Calibration and planning with a pedicle-lamina angle]. Neurochirurgie 2016; 62:209-12. [PMID: 27236736 DOI: 10.1016/j.neuchi.2015.10.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 09/24/2015] [Accepted: 10/30/2015] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Posterior cervical arthrodesis is associated with osteosynthesis. C2 pedicular screwing affords a good bone anchoring but involves neurological and vascular risks. PURPOSE To determine C2 pedicular screwing feasibility from a large cohort of cervical CT scans. To describe the visible anatomical parameters during a surgical procedure in order to plan and secure it. MATERIALS AND METHODS Retrospective consecutive series of 100 cervical CT scans was analyzed. Cases with upper cervical fracture were excluded. C2 surgical anatomy was assessed according to maximum length, minimum width and minimum height. Angular parameters were pedicle-transverse angle and sagittal angle. Original pedicle-lamina angle was used as a visible mark during the procedure independent of the patient's position. Pedicular screwing feasibility was evaluated. It was arbitrarily defined by a lower minimum height less than 4mm. RESULTS Two hundred C2 pedicles were analyzed with 7.5% that were not screwable. Their mean length was 26.2mm, with a mean width of 5.2mm and a mean height of 9.2mm. Mean pedicle-transverse angle was 36.2°, mean sagittal angle was 25.8° and mean pedicle-lamina angle was 81.3°. CONCLUSION C2 pedicle screwing feasibility is inconstant due to anatomical variability. In fact, 13% of patients have at least one non-screwable pedicle. Preoperative planning is essential to achieve this procedure. A pedicle-lamina angle can be used which remains independent from the patient's position.
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Affiliation(s)
- S Le Pape
- Service d'orthopédie-traumatologie, institut régional du rachis, hôpital C.-Nicolle, CHU de Rouen, 1, rue de Gérmont, 76031 Rouen cedex, France
| | - R Gauthe
- Service d'orthopédie-traumatologie, institut régional du rachis, hôpital C.-Nicolle, CHU de Rouen, 1, rue de Gérmont, 76031 Rouen cedex, France
| | - C Latrobe
- Service d'orthopédie-traumatologie, institut régional du rachis, hôpital C.-Nicolle, CHU de Rouen, 1, rue de Gérmont, 76031 Rouen cedex, France
| | - P Cantogrel
- Service d'orthopédie-traumatologie, institut régional du rachis, hôpital C.-Nicolle, CHU de Rouen, 1, rue de Gérmont, 76031 Rouen cedex, France
| | - F Proust
- Service d'orthopédie-traumatologie, institut régional du rachis, hôpital C.-Nicolle, CHU de Rouen, 1, rue de Gérmont, 76031 Rouen cedex, France
| | - J Leroux
- Clinique chirurgicale infantile, CHU de Rouen, 1, rue de Gérmont, 76031 Rouen cedex, France
| | - M Ould-Slimane
- Service d'orthopédie-traumatologie, institut régional du rachis, hôpital C.-Nicolle, CHU de Rouen, 1, rue de Gérmont, 76031 Rouen cedex, France.
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Zhai MY, Wang CP, Liu F, Liu YQ, Zhang P. The efficacy of pedicle screw instrument in treatment of irreducible atlantoaxial dislocation. Arch Orthop Trauma Surg 2015; 135:1193-9. [PMID: 26119708 DOI: 10.1007/s00402-015-2261-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2014] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To explore the effect of pedicle screw instrument in treatment of irreducible atlantoaxial dislocation. PATIENTS AND METHOD From June 2003 to February 2009, 14 cases of atlas dislocation with upper cervical cord compression were enrolled and anterior transoral soft tissue release combined with posterior reduction and pedicle screw fixation were performed. CT, MRI and radiograph were used preoperatively, and screw placement and bone graft were administered in all cases intraoperatively. Cervical collars were used for 3 months. RESULTS Screws were successfully placed in atlas in all cases. The average follow-up period was 18 months. Bone fusion was observed in all cases without the following complications: neurologic symptoms, internal fixation failure and redislocation. Neurological recovery was observed in all 14 cases. CONCLUSIONS Pedicle screw instrument has the following advantages in atlas and axis injury treatment: direct screw placement, short-segment fusion, intraoperative reduction and high fusion rate, which should be a better surgical method for the treatment of atlantoaxial dislocation.
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Affiliation(s)
- Ming-Yu Zhai
- Spinal Surgery Center of Ping Le Orthopaedic Hospital, Shenzhen, 518001, Guang Dong, China,
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Yin Q, Wang J. Current Trends in Management of Atlantoaxial Dislocation. Orthop Surg 2015; 7:189-99. [PMID: 26311092 PMCID: PMC6583745 DOI: 10.1111/os.12196] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 06/26/2015] [Indexed: 01/26/2023] Open
Abstract
Atlantoaxial dislocation (AAD), often caused by trauma, tumors or congenital malformations, is a challenging disorder of the craniocervical junction. Because of its deep location and intricate anatomic structure, the craniocervical junction is always a difficult region for spine surgery. With recent developments in medical science, great progress has been made in the diagnosis and treatment of AAD such that more instructive clinical classifications and efficacious treatment strategies, various novel operation techniques including innovative posterior or transoral anterior reduction, and novel fixation instruments are now widely used in clinical practice for managing AAD. However, surgeons continue to face more special characteristics and difficulty in carrying out upper cervical surgery than they encounter in other regions of the spine. Consequently, this high risk surgery should only be performed by extremely skilled and experienced surgeons and only when stringent indications have been met. Therefore, the aim of this course is to assist surgeons who are dealing with AAD by providing comprehensive information about AAD, including related anatomy, classification, clinical manifestations and diagnosis, imaging examinations and surgical techniques, thus decreasing the occurrence of complications and improving the level of diagnosis and treatment.
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Affiliation(s)
- Qing‐shui Yin
- Orthopaedic HospitalGeneral Hospital of Guangzhou Military Command of People's Liberation ArmyGuangzhouChina
| | - Jian‐hua Wang
- Orthopaedic HospitalGeneral Hospital of Guangzhou Military Command of People's Liberation ArmyGuangzhouChina
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Is the 4 mm height of the vertebral artery groove really a limitation of C1 pedicle screw insertion? EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2014; 23:1109-14. [PMID: 24509775 DOI: 10.1007/s00586-014-3217-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/23/2014] [Accepted: 01/25/2014] [Indexed: 10/25/2022]
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