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Pepke W, Renkawitz T, Hemmer S. Treatment of Klippel-Feil syndrome with symptomatic atlantoaxial instability in a 7-year-old boy : A case report. ORTHOPADIE (HEIDELBERG, GERMANY) 2024:10.1007/s00132-024-04537-z. [PMID: 39117750 DOI: 10.1007/s00132-024-04537-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/01/2024] [Indexed: 08/10/2024]
Abstract
Klippel-Feil syndrome (KFS) is a congenital deformity of the cervical spine. Clinical symptoms of KFS are reduced range of motion, short neck and low hairline. In adult KFS patients the deformity can lead to adjacent segmental instability with spinal canal stenosis, radiculopathy and myelopathy. This article reports about the diagnostics and treatment management of juvenile KFS patient with myelopathy due to instability of the C1/C2 segment, subsequent stenosis through the posterior arch of C1 and symptomatic myelopathy. This 7‑year-old boy could be successfully treated with C1 decompression and computer tomography (CT) guided C1/C2 stabilization with pedicle screws under intraoperative neuromonitoring.
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Affiliation(s)
- W Pepke
- Department of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany
| | - T Renkawitz
- Department of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany
| | - S Hemmer
- Department of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany.
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Sakhrekar R, Shkumat N, Ertl-Wagner B, Lewis S, Lebel D, McVey MJ, Camp M. Pedicle screw accuracy placed with assistance of machine vision technology in patients with neuromuscular scoliosis. Spine Deform 2024; 12:739-746. [PMID: 38413472 DOI: 10.1007/s43390-024-00830-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 01/13/2024] [Indexed: 02/29/2024]
Abstract
INTRODUCTION Pedicle screws are the primary method of vertebral fixation in scoliosis surgery, but there are lingering concerns over potential malposition. The rates of pedicle screw malposition in pediatric spine surgery vary from 10% to 21%. Malpositioned screws can lead to potentially catastrophic neurological, vascular, and visceral complications. Pedicle screw positioning in patients with neuromuscular scoliosis is challenging due to a combination of large curves, complex pelvic anatomy, and osteopenia. This study aimed to determine the rate of pedicle screw malposition, associated complications, and subsequent revision from screws placed with the assistance of machine vision navigation technology in patients with neuromuscular scoliosis undergoing posterior instrumentation and fusion. METHOD A retrospective analysis of the records of patients with neuromuscular scoliosis who underwent thoracolumbar pedicle screw insertion with the assistance of machine-vision image guidance navigation was performed. Screws were inserted by either a staff surgeon, orthopaedic fellow, or orthopaedic resident. Post-operative ultra-low dose CT scans were used to assess pedicle screw accuracy. The Gertzbein classification was used to grade any pedicle breaches (grade 0, no breach; grade 1, <2 mm; grade 2, 2-4 mm; grade 3, >4 mm). A screw was deemed accurate if no breach was identified (grade 0). RESULTS 25 patients were included in the analysis, with a mean age of 13.6 years (range 11 to 18 years; 13/25 (52.0%) were female. The average pre-operative supine Cobb angle was 90.0 degrees (48-120 degrees). A total of 687 screws from 25 patients were analyzed (402 thoracic, 241 lumbosacral, 44 S2 alar-iliac (S2AI) screws). Surgical trainees (fellows and orthopaedic residents) inserted 46.6% (320/687) of screws with 98.8% (4/320) accuracy. The overall accuracy of pedicle screw insertion was 98.0% (Grade 0, no breach). All 13 breaches that occurred in the thoracic and lumbar screws were Grade 1. Of the 44 S2AI screws placed, one screw had a Grade 3 breach (2.3%) noted on intra-operative radiographs following rod placement and correction. This screw was subsequently revised. None of the breaches resulted in neuromonitoring changes, vessel, or visceral injuries. CONCLUSION Machine vision navigation technology combined with careful free-hand pedicle screw insertion techniques demonstrated high levels of pedicle screw insertion accuracy, even in patients with challenging anatomy.
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Affiliation(s)
- Rajendra Sakhrekar
- Division of Orthopaedic Surgery, University of Toronto, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
| | - Nicholas Shkumat
- Department of Diagnostic Imaging, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - Birgit Ertl-Wagner
- Department of Diagnostic Imaging, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - Stephen Lewis
- Division of Orthopaedic Surgery, University of Toronto, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - David Lebel
- Division of Orthopaedic Surgery, University of Toronto, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - M J McVey
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia and Pain Medicine, Hospital for Sick Children, Toronto, ON, Canada
- Department of Physics, Toronto Metropolitan University, Toronto, ON, Canada
| | - Mark Camp
- Division of Orthopaedic Surgery, University of Toronto, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
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Oppermann M, Karapetyan V, Gupta S, Ramjist J, Oppermann P, Yang VXD. The pedicle screw accuracy using a robotic system and measured by a novel three-dimensional method. J Orthop Surg Res 2023; 18:706. [PMID: 37730623 PMCID: PMC10510280 DOI: 10.1186/s13018-023-04206-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 09/13/2023] [Indexed: 09/22/2023] Open
Abstract
Robotics in medicine is associated with precision, accuracy, and replicability. Several robotic systems are used in spine surgery. They are all considered shared-control systems, providing "steady-hand" manipulation instruments. Although numerous studies have testified to the benefits of robotic instrumentations, they must address their true accuracy. Our study used the Mazor system under several situations and compared the spatial accuracy of the pedicle screw (PS) insertion and its planned trajectory. We used two cadaveric specimens with intact spinal structures from C7 to S1. PS planning was performed using the two registration methods (preopCT/C-arm or CT-to-fluoroscopy registration). After planning, the implant spatial orientation was defined based on six anatomic parameters using axial and sagittal CT images. Two surgical open and percutaneous access were used to insert the PS. After that, another CT acquisition was taken. Accuracy was classified into optimal, inaccurate and unacceptable according to the degree of screw deviation from its planning using the same spatial orientation method. Based on the type of spatial deviation, we also classified the PS trajectory into 16 pattern errors. Seven (19%) out of 37 implanted screws were considered unacceptable (deviation distances > 2.0 mm or angulation > 5°), and 14 (38%) were inaccurate (> 0.5 mm and ≤ 2.0 mm or > 2.5° and ≤ 5°). CT-to-fluoroscopy registration was superior to preopCT/C-arm (average deviation in 0.9 mm vs. 1.7 mm, respectively, p < 0.003), and percutaneous was slightly better than open but did not reach significance (1.3 mm vs. 1.7 mm, respectively). Regarding pattern error, the tendency was to have more axial than sagittal shifts. Using a quantitative method to categorize the screw 3D position, only 10.8% of the screws were considered unacceptable. However, with a more rigorous concept of inaccuracy, almost half were non-optimal. We also identified that, unlike some previous results, the O-arm registration delivers more accurate implants than the preopCT/C-arm method.
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Affiliation(s)
- Marcelo Oppermann
- Department of Clinical Neurological Science, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada.
- Department of Electrical Computer and Biomedical Engineering, Toronto Metropolitan University, Toronto, ON, Canada.
| | - Vahagan Karapetyan
- Department of Clinical Neurological Science, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Shaurya Gupta
- Department of Electrical Computer and Biomedical Engineering, Toronto Metropolitan University, Toronto, ON, Canada
| | - Joel Ramjist
- Department of Electrical Computer and Biomedical Engineering, Toronto Metropolitan University, Toronto, ON, Canada
| | - Priscila Oppermann
- Department of Clinical Neurological Science, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Victor X D Yang
- Department of Clinical Neurological Science, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Department of Electrical Computer and Biomedical Engineering, Toronto Metropolitan University, Toronto, ON, Canada
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Liu HT, Liang ZH, Song J, Zhang HW, Zhou FC, Zhang QQ, Shao J, Zhang YH. Posterior Atlantoaxial Fusion With C1-2 Pedicle Screw Fixation for Atlantoaxial Dislocation in Pediatric Patients With Mucopolysaccharidosis IVA (Morquio a Syndrome): A Case Series. World Neurosurg 2023; 175:e574-e581. [PMID: 37028486 DOI: 10.1016/j.wneu.2023.03.145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 03/30/2023] [Accepted: 03/31/2023] [Indexed: 04/09/2023]
Abstract
OBJECTIVE To investigate the efficacy and safety of posterior atlantoaxial fusion (AAF) with C1-2 pedicle screw fixation for atlantoaxial dislocation (AAD) in pediatric patients with mucopolysaccharidosis IVA (MPS IVA). METHODS This study included 21 pediatric patients with MPS IVA who underwent posterior AAF with C1-2 pedicle screw fixation. Anatomical parameters of the C1 and C2 pedicle were measured on preoperative computed tomography (CT). The American Spinal Injury Association (ASIA) scale was used to evaluate the neurological status. The fusion and accuracy of pedicle screw was assessed on postoperative CT. Demographic, radiation dose, bone density, surgical, and clinical data were recorded. RESULTS Patients reviewed included 21 patients younger than 16 years with an average age of 7.4 ± 4.2 years and an average of 20.9 ± 7.7 months follow-up. Fixation of 83 C1 and C2 pedicle screws was performed successfully and 96.3% of them were identified as being safe. One patient developed postoperative transient disturbance of consciousness and one developed fetal airway obstruction and died about 1 month after the surgery. Out of the remaining20 patients, fusion was achieved, symptoms were improved, and no other serious surgical complications were observed at the latest follow-up. CONCLUSIONS Posterior AAF with C1-2 pedicle screw fixation is effective and safe for AAD in pediatric patients with MPS IVA. However, the procedure is technically demanding and should be performed by experienced surgeons with strict multidisciplinary consultations.
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Affiliation(s)
- Hai-Tao Liu
- Spine Center, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhi-Hui Liang
- Spine Center, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jia Song
- Spine Center, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hui-Wen Zhang
- Department of Endocrinology and Genetics, Shanghai Institute of Pediatrics, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fu-Chao Zhou
- Spine Center, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Qiu-Qi Zhang
- Spine Center, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jiang Shao
- Spine Center, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yue-Hui Zhang
- Spine Center, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Diltz ZR, Sheffer BJ. Intraoperative Navigation and Robotics in Pediatric Spinal Deformity. Orthop Clin North Am 2023; 54:201-207. [PMID: 36894292 DOI: 10.1016/j.ocl.2022.11.005] [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: 03/11/2023]
Abstract
Current technologies for image guidance navigation and robotic assistance with spinal surgery are improving rapidly with several systems commercially available. Newer machine vision technology has several potential advantages. Limited studies have shown similar outcomes to traditional navigation platforms with decreased intraoperative radiation and time required for registration. However, there are no active robotic arms that can be coupled with machine vision navigation. Further research is necessary to justify the cost, potential increased operative time, and workflow issues but the use of navigation and robotics will only continue to expand given the growing body of evidence supporting their use.
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Affiliation(s)
- Zachary R Diltz
- Department of Orthopedic Surgery, LeBonheur Children's Hospital, 848 Adams Avenue, Memphis, TN 38103, USA; Department of Orthopedic Surgery, Campbell Clinic, University of Tennessee Health Science Center, 1211 Union Avenue, Memphis, TN 38104, USA; Campbell Clinic Orthopedics, 1400 South Germantown Road, Germantown, TN 38138, USA
| | - Benjamin J Sheffer
- Department of Orthopedic Surgery, LeBonheur Children's Hospital, 848 Adams Avenue, Memphis, TN 38103, USA; Department of Orthopedic Surgery, Campbell Clinic, University of Tennessee Health Science Center, 1211 Union Avenue, Memphis, TN 38104, USA; Campbell Clinic Orthopedics, 1400 South Germantown Road, Germantown, TN 38138, USA.
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State of the art review of new technologies in spine deformity surgery-robotics and navigation. Spine Deform 2022; 10:5-17. [PMID: 34487345 PMCID: PMC8741671 DOI: 10.1007/s43390-021-00403-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 08/14/2021] [Indexed: 12/24/2022]
Abstract
STUDY DESIGN/METHODS Review article. OBJECTIVES The goal of this article is to review the available evidence for computerized navigation and robotics as an accuracy improvement tool for spinal deformity surgery, as well as to consider potential complications, impact on clinical outcomes, radiation exposure, and costs. Pedicle screw and rod construct are widely utilized for posterior spinal fixation in spinal deformity correction. Freehand placement of pedicle screws has long been utilized, although there is variable potential for inaccuracy depending on surgeon skill and experience. Malpositioned pedicle screws may have significant clinical implications ranging from nerve root irritation, inadequate fixation, CSF leak, perforation of the great vessels, or spinal cord damage. Computer-based navigation and robotics systems were developed to improve pedicle screw insertion accuracy and consistency, and decrease the risk of malpositioned pedicle fixation. The available evidence suggests that computer-based navigation and robotic-assisted guidance systems for pedicle cannulation are at least equivalent, and in several reports superior, to freehand techniques in terms of accuracy. CT and robotic navigation systems do appear to decrease radiation exposure to the operative team in some reports. Published reports do indicate longer operative times with use of robotic navigation compared with traditional freehand techniques for pedicle screw placement. To date, there is no conclusive evidence that use of CT or robotic navigation has any measurable impact on patient outcomes or overall complication reduction. There are theoretical advantages with robotic and CT navigation in terms of both speed and accuracy for severe spinal deformity or complex revision cases, however, there is a need for studies to investigate this technology in these specific cases. There is no evidence to date demonstrating the cost effectiveness of CT or robotic navigation as compared with traditional pedicle cannulation techniques. CONCLUSIONS The review of available evidence suggests that computer-based navigation and robotic-assisted guidance systems for pedicle cannulation are at least equivalent, and in several reports superior, to freehand techniques in terms of radiographic accuracy. There is no current clinical evidence that the use of navigation or robotic techniques leads to improved patient outcomes or decreased overall complications or reoperation rates, and the use of these systems may substantially increase surgical costs. LEVEL OF EVIDENCE V.
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Linden GS, Birch CM, Hresko MT, Cook D, Hedequist DJ. Intraoperative Use of Robotics With Navigation for Pedicle Screw Placement in Treatment of Pediatric High-grade Spondylolisthesis: A Preliminary Report. J Pediatr Orthop 2021; 41:591-596. [PMID: 34516471 DOI: 10.1097/bpo.0000000000001947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Accurate pedicle screw placement is critical to surgically correct pediatric high-grade spondylolisthesis (HGS). The recent advent of robotics coupled with computer-assisted navigation (RAN) may represent a novel option to improve surgical outcomes of HGS, secondary to enhanced pedicle screw placement safety. This series presents the HGS-RAN technique adopted by our site, describing its surgical outcomes and feasibility. METHODS Consecutive patients with a diagnosis of HGS (Meyerding grade III to V), operated on using RAN from 2019 to 2020 at a single-center were reviewed. Demographics, screw accuracy, sagittal L5-S1 parameters, complications, and perioperative outcomes were described. All patients were treated with instrumentation, decompression, posterior lumbar interbody fusion, and reduction. Robotic time included anatomic registration to end of screw placement. Screw accuracy-defined as a screw placed safely within the planned intrapedicular trajectory-was characterized by the Gertzbein-Robbins system for patients with additional 3-dimensional imaging. RESULTS Ten HGS patients, with an average age of 13.7 years old, were included in the series. All 62 screws were placed without neurological deficit or complication. Seven patients had additional 3-dimensional imaging to assess screw accuracy (42 of 62 screws). One hundred percent of screws were placed safely with no pedicle breaches (Gertzbein-Robbins-grade A). Thirty screws (48%) were placed through separate incisions that were percutaneous/transmuscular and 32 screws (52%) were inserted through the main incision. There were statistically significant improvements in L5 slippage (P=0.002) and lumbosacral angle (P=0.002), reflecting successful HGS correction. The total median operative time was 324 minutes with the robotic usage time consuming a median of 72 minutes. Median estimated blood loss was 150 mL, and length-of-stay was a median 3 days. CONCLUSIONS This case-series demonstrates that RAN represents a viable option for HGS repair, indicated by high screw placement accuracy, safety, and L5-S1 slippage correction. Surgeons looking to adopt an emerging technique to enhance safety and correction of pediatric HGS should consider the RAN platform. LEVEL OF EVIDENCE Level IV-therapeutic study.
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Affiliation(s)
| | - Craig M Birch
- Department of Orthopaedic Surgery, Boston Children's Hospital
- Harvard Medical School, Boston, MA
| | - M Timothy Hresko
- Department of Orthopaedic Surgery, Boston Children's Hospital
- Harvard Medical School, Boston, MA
| | - Danielle Cook
- Department of Orthopaedic Surgery, Boston Children's Hospital
| | - Daniel J Hedequist
- Department of Orthopaedic Surgery, Boston Children's Hospital
- Harvard Medical School, Boston, MA
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Kumar V, Baburaj V, Patel S, Sharma S, Vaishya R. Does the use of intraoperative CT scan improve outcomes in Orthopaedic surgery? A systematic review and meta-analysis of 871 cases. J Clin Orthop Trauma 2021; 18:216-223. [PMID: 34040978 PMCID: PMC8138210 DOI: 10.1016/j.jcot.2021.04.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Intraoperative imaging is frequently made use of in Orthopaedic surgery. Historically, conventional 2-dimensional fluoroscopy has been extensively used for this purpose. However, 2D imaging falls short when it is required to visualise complex anatomical regions such as pelvis, spine, foot and ankle etc. Intraoperative 3D imaging was introduced to counter these limitations, and is increasingly being employed in various sub-specialities of Orthopaedic Surgery. OBJECTIVES This review aims to outline the clinical and radiological outcomes of surgeries done under the guidance of intraoperative 3D imaging and compare them to those done under conventional 2D fluoroscopy. METHODS Three electronic databases (PubMed, Embase and Scopus) were searched for relevant studies that directly compared intraoperative 3D imaging with conventional fluoroscopy. Case series on intraoperative 3D imaging were also included for qualitative synthesis. The outcomes evaluated included accuracy of implant placement, mean surgical duration and rate of revision surgery due to faulty implants. RESULTS A total of 31 studies from sub-specialities of spine surgery, pelvi-acetabular surgery, foot and ankle surgery and trauma surgery, having data on a total of 658 patients were analysed. The study groups which had access to intraoperative 3D imaging was found to have significantly increased accuracy of implant positioning (Odds Ratio 0.35 [0.20, 0.62], p = 0.0002) without statistically significant difference in mean surgical time (p = 0.57). Analysis of the studies that included clinical follow up showed that the use of intraoperative 3D imaging led to a significant decrease in the need for revision surgeries due to faulty implant placement. CONCLUSION There is sufficient evidence that the application of intraoperative 3D imaging leads to precise implant positioning and improves the radiological outcome. Further research in the form of prospective studies with long term follow up is required to determine whether this superior radiological outcome translates to better clinical results in the long run.
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Affiliation(s)
- Vishal Kumar
- Department of Orthopaedics, Postgraduate Institute of Medial Education and Research, Chandigarh, India
| | - Vishnu Baburaj
- Department of Orthopaedics, Postgraduate Institute of Medial Education and Research, Chandigarh, India
| | - Sandeep Patel
- Department of Orthopaedics, Postgraduate Institute of Medial Education and Research, Chandigarh, India
| | - Siddhartha Sharma
- Department of Orthopaedics, Postgraduate Institute of Medial Education and Research, Chandigarh, India
| | - Raju Vaishya
- Department of Orthopaedics, Indraprastha Apollo Hospitals, New Delhi, India
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Yang X, Luo Q, Li ZQ, Zhang N, Chen XY, Zhou Y, Deng HL, Jiang J, Liu JM. Using the lamina nutrient foramen as the entry point for posterior cervical pedicle screw placement. Clin Neurol Neurosurg 2021; 207:106711. [PMID: 34102421 DOI: 10.1016/j.clineuro.2021.106711] [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: 02/11/2021] [Revised: 04/07/2021] [Accepted: 05/23/2021] [Indexed: 10/21/2022]
Abstract
STUDY DESIGN A prospective study and technique description. OBJECTIVE This study introduced a method for posterior cervical pedicle screw placement by using the bilateral posterior lamina nutrient foramens as the entry point. METHODS Firstly, 30 dry C3-C7 vertebrae specimens were harvested for measurement. The lamina nutrient foramens were used as the entry points for posterior cervical pedicle screw placement and four linear and two angle parameters were obtained from a computed tomography scan(CT). Then, 60 patients who underwent C3-C7 pedicle screw fixation using this method were included, linear and angle parameters were obtained from a postoperative CT. RESULTS The average incidences of lamina nutrient foramen on the C3-C7 specimens were 88.3%, 90.0%, 95.0%, 95.0%, and 96.7%, respectively. The distances from the entry point to the pedicle screw tip (OD), the pedicle transverse angles (α), and the pedicle sagittal angles (β) measure for the entry points from C3-C7 were 28.74 ± 3.45-30.15 ± 2.01 mm, 26.88 ± 6.89° to 32.72 ± 5.91°, and 12.48 ± 9.31° to 19.71 ± 8.45°, respectively, with no significant differences between the left and right sides. In the 60 patients who underwent surgery, the lengths of the pedicle screws (PL) were 28.34 ± 2.25-30.15 ± 2.31 mm, the pedicle transverse angles (α) were 26.89 ± 6.86° to 32.36 ± 5.65°, and the pedicle sagittal angles (β) were 12.49 ± 9.11° to 20.06 ± 8.91°. The new method had a 96.8% (454/469) success rate among these patients, with no screws penetrating the spinal canal or signs of vertebral artery injury. CONCLUSION Entry at the bilateral lamina nutrient foramen represents an alternative posterior cervical pedicle screw placement technique that is feasible and safe.
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Affiliation(s)
- Xuan Yang
- Medical Innovation Center, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China; The First Clinical Medical College of Nanchang University, Nanchang 330006, PR China
| | - Qing Luo
- Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Zhi-Qiang Li
- Medical Innovation Center, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China; Institute of Spine and Spinal Cord, Nanchang University, Nanchang 330006, PR China
| | - Ning Zhang
- Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
| | - Xuan-Yin Chen
- Medical Innovation Center, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China; Institute of Spine and Spinal Cord, Nanchang University, Nanchang 330006, PR China
| | - Yang Zhou
- Medical Innovation Center, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China; Institute of Spine and Spinal Cord, Nanchang University, Nanchang 330006, PR China
| | - Hui-Lin Deng
- Medical Innovation Center, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China; Institute of Spine and Spinal Cord, Nanchang University, Nanchang 330006, PR China
| | - Jian Jiang
- Department of Radiology, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China.
| | - Jia-Ming Liu
- Medical Innovation Center, the First Affiliated Hospital of Nanchang University, Nanchang 330006, PR China; Institute of Spine and Spinal Cord, Nanchang University, Nanchang 330006, PR China.
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Kochanski RB, Lombardi JM, Laratta JL, Lehman RA, O'Toole JE. Image-Guided Navigation and Robotics in Spine Surgery. Neurosurgery 2020; 84:1179-1189. [PMID: 30615160 DOI: 10.1093/neuros/nyy630] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 12/04/2018] [Indexed: 01/27/2023] Open
Abstract
Image guidance (IG) and robotics systems are becoming more widespread in their utilization and can be invaluable intraoperative adjuncts during spine surgery. Both are highly reliant upon stereotaxy and either pre- or intraoperative radiographic imaging. While user-operated IG systems have been commercially available longer and subsequently are more widely utilized across centers, robotics systems provide unique theoretical advantages over freehand and IG techniques for placing instrumentation within the spine. While there is a growing plethora of data showing that IG and robotic systems decrease the incidence of malpositioned screws, less is known about their impact on clinical outcomes. Both robotics and IG may be of particular value in cases of substantial deformity or complex anatomy. Indications for the use of these systems continue to expand with an increasing body of literature justifying their use in not only guiding thoracolumbar pedicle screw placement, but also in cases of cervical and pelvic instrumentation as well as spinal tumor resection. Both techniques also offer the potential benefit of reducing occupational exposures to ionizing radiation for the operating room staff, the surgeon, and the patient. As the use of IG and robotics in spine surgery continues to expand, these systems' value in improving surgical accuracy and clinical outcomes must be weighed against concerns over cost and workflow. As newer systems incorporating both real-time IG and robotics become more utilized, further research is necessary to better elucidate situations where these systems may be particularly beneficial in spine surgery.
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Affiliation(s)
- Ryan B Kochanski
- Department of Neurosurgery, Rush University Medical Center, Chicago, Illinois
| | - Joseph M Lombardi
- Department of Orthopedic Surgery, Columbia University, New York, New York
| | - Joseph L Laratta
- Department of Orthopedic Surgery, Columbia University, New York, New York
| | - Ronald A Lehman
- Department of Orthopedic Surgery, Columbia University, New York, New York
| | - John E O'Toole
- Department of Neurosurgery, Rush University Medical Center, Chicago, Illinois
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Ankory R, Kadar A, Netzer D, Schermann H, Gortzak Y, Dadia S, Kollander Y, Segal O. 3D imaging and stealth navigation instead of CT guidance for radiofrequency ablation of osteoid osteomas: a series of 52 patients. BMC Musculoskelet Disord 2019; 20:579. [PMID: 31787079 PMCID: PMC6886227 DOI: 10.1186/s12891-019-2963-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 11/22/2019] [Indexed: 11/20/2022] Open
Abstract
Background Osteoid osteomas are benign bone neoplasms that may cause severe pain and limit function. They are commonly treated by radiofrequency ablation (RFA) through a needle inserted into the nidus of the lesion under CT guidance, which is associated with exposure of young patients to relatively high dose of radiation. The objective of this study was to investigate the amount of radiation, effectiveness and safety of an alternative imaging approach, the 3D image-guided (O-arm) technology and the Stealth navigation. Methods We retrospectively reviewed 52 electronic medical files of patients (mean age 24.7 years, range 8–59 years) who were treated with thermal ablation of benign osteoid osteomas guided by the navigated O-arm-assisted technique in our institution between 2015 and 2017. Data were extracted on the associated complications, the reduction in pain at 3 months and one year postoperatively, and the amount of radiation administered during the procedure. Results The level of pain on a visual analogue scale decreased from the preoperative average of 7.73 to 0 at the 3-month follow-up. The mean dose-length product was 544.7 mGycm2 compared to the reported radiation exposure of 1971–7946 mGycm2 of CT-guided radio ablations. The one intra-operative complication was a superficial burn in the subcutaneous lesion in a tibia that was treated locally with no major influence on recovery. Conclusions RFA ablation guided by 3D O-arm stealth navigation is as effective as the traditional CT-guided technique with the advantage of lower radiation exposure. Trial registration Retrospective study number 0388–17-TLV at Tel Aviv Sourasky Medical Center IRB, approved at 25.10.17.
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Affiliation(s)
- Ran Ankory
- Division of Orthopedics, Tel Aviv Sourasky Medical Center affiliated with Tel Aviv University, 153 Arlozorov st app 6, 6492211, Tel Aviv, Israel
| | - Assaf Kadar
- Division of Orthopedics, Tel Aviv Sourasky Medical Center affiliated with Tel Aviv University, 153 Arlozorov st app 6, 6492211, Tel Aviv, Israel
| | - Doron Netzer
- Meir Medical Center, Kfar Sava, Israel affiliated with Tel Aviv University, Tel Aviv, Israel
| | - Haggai Schermann
- Division of Orthopedics, Tel Aviv Sourasky Medical Center affiliated with Tel Aviv University, 153 Arlozorov st app 6, 6492211, Tel Aviv, Israel.
| | - Yair Gortzak
- The National Unit for Orthopedic Oncology, Tel Aviv Sourasky Medical Center affiliated with Tel Aviv University, Tel Aviv, Israel
| | - Shlomo Dadia
- The National Unit for Orthopedic Oncology, Tel Aviv Sourasky Medical Center affiliated with Tel Aviv University, Tel Aviv, Israel
| | - Yehuda Kollander
- The National Unit for Orthopedic Oncology, Tel Aviv Sourasky Medical Center affiliated with Tel Aviv University, Tel Aviv, Israel
| | - Ortal Segal
- The National Unit for Orthopedic Oncology, Tel Aviv Sourasky Medical Center affiliated with Tel Aviv University, Tel Aviv, Israel
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12
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Efficacy and Safety of Atlantoaxial Fluoroscopy-guided Pedicle Screw Fixation in Patients Younger Than 12 Years: A Radiographic and Clinical Assessment. Spine (Phila Pa 1976) 2019; 44:1412-1417. [PMID: 31589199 DOI: 10.1097/brs.0000000000003139] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A retrospective clinical study. OBJECTIVE The aim of this study was to evaluate the efficacy and safety of fluoroscopy-guided atlantoaxial pedicle screw fixation in patients younger than 12 years. SUMMARY OF BACKGROUND DATA C1-C2 pedicle screw fixation is a widely accepted treatment method for atlantoaxial dislocation (AAD). However, data regarding its use for atlantoaxial fusion (AAF) in children are limited. METHODS Thirty-six consecutive patients younger than 12 years underwent C1-C2 pedicle screw fixation for AAD between 2007 and 2017. Anatomical parameters of the C1 pedicle were measured on preoperative computed tomography (CT). Accuracy of pedicle screw fixation was assessed on postoperative CT using the following definitions: Type I, screw threads completely within the bone; Type II, less than half the diameter of the screw violating the surrounding cortex; and Type III, clear violation of the transverse foramen or spinal canal. Demographic, surgical, radiation dose, and clinical data were recorded. RESULTS Patients underwent 144 screw fixations (67 C1 pedicle screws, 68 C2 pedicle screws, 5 C1 lateral mass screws, and 4 C-2 laminar screws) for a variety of pediatric AADs, with 36.5 ± 8.5 months of follow-up. Among the 135 pedicle screws, 96.3% were deemed "safe" (Type I or II) and 80.7% (109/135) of the screws were rated as being ideal (Type I); five screws (3.7%) were identified as unacceptable (Type III). Average estimated blood loss (EBL) was 92 mL, and the average total radiation exposure during the operation was 6.2 mGy (in the final 26 cases). There were no neurovascular injuries. All patients showed radiographic stability and symptom resolution. CONCLUSION C1-C2 pedicle screw fixation under fluoroscopy is safe and effective for the treatment of AAD in children younger than 12 years. However, it may be technically challenging owing to the special anatomical features of children and should be performed by experienced surgeons. LEVEL OF EVIDENCE 3.
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13
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Min WK, Na SB, Jang JA. Accuracy of thoracic pedicle screw placement using freehand technique and triggered EMG in adolescent idiopathic scoliosis: Is it different between concave and convex side? J Orthop Surg (Hong Kong) 2019; 26:2309499018784975. [PMID: 29954289 DOI: 10.1177/2309499018784975] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
PURPOSE To evaluate and compare the accuracy of the placement of thoracic pedicle screws between concave and convex side curve using freehand technique and triggered electromyogram (EMG). METHODS Three-hundred sixty eight thoracic pedicle screws were included for the evaluation of accuracy from postoperative computed tomography (CT) scans in 24 patients with adolescent idiopathic scoliosis with a mean follow-up of 27 months (range 24-58 months). All screws had stimulation thresholds greater than 6 mA. We divided the screws into two groups: (1) group A: concave side curve-254 screws (2) group B: convex side curve-114 screws. RESULTS The mean age at surgery was 12.8 years (range 11-17 years). The preoperative Cobb angle was 57.5° (range 50-75°). There were 41 total breaches (medial = 21, lateral = 20, p = 0.66) with an overall incidence of 11.1%. The overall breach rate did not attain statistically significant difference (group A = 11.8%, group B = 9.6%, p = 0.59). The rate of medial breaches was also similar for both concave and convex side (group A = 6.1%, group B = 5.9%, p > 0.05). No postoperative neurological or vascular complications were noted in both groups. CONCLUSION Thoracic pedicle screw placement using both freehand technique and triggered EMG for adolescent idiopathic scoliosis surgery is safe and reliable. The overall accuracy rate is 88.9% with similar breaches on the concave and convex side on postoperative CT scans.
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Affiliation(s)
- Woo-Kie Min
- Department of Orthopedic Surgery, College of Medicine, Kyungpook National University Hospital, Daegu, South Korea
| | - Sang-Bong Na
- Department of Orthopedic Surgery, College of Medicine, Kyungpook National University Hospital, Daegu, South Korea
| | - Jin-An Jang
- Department of Orthopedic Surgery, College of Medicine, Kyungpook National University Hospital, Daegu, South Korea
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14
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Garg S, Palmer C, Whitmore W, Cyr M, Michael N, Kim E, Boucharel W. Triggered EMG (T-EMG) Values of Pedicle Screws with a Powered Screwdriver vs A Standard Probe in Adolescent Idiopathic Scoliosis Do Not Agree: A Prospective Validation Study. Neurodiagn J 2019; 59:152-162. [PMID: 31251123 DOI: 10.1080/21646821.2019.1630211] [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: 10/26/2022]
Abstract
Triggered electromyography (t-EMG) is a common technique used during spinal instrumentation in surgery for adolescent idiopathic scoliosis. This study tests the validity of t-EMG values obtained with a standard ball-tipped probe after completion of screw placement versus t-EMG values obtained during screw insertion with a powered screwdriver. t-EMG values were collected for screws spanning T7-L5 using both a standard probe and a powered screwdriver. A power analysis determined that a sample size of 300 screws would provide enough precision to estimate limits of agreement within ±2 mA. A monopolar constant current stimulation technique (0.2 ms duration and 3.11 Hz stimulation rate) was used at each level. EMG was acquired with placement of bipolar pairs of subdermal needle electrodes. A Bland-Altman plot was used to assess agreement between threshold readings from the two techniques. Twenty-nine patients were enrolled in this study with 305 screws. t-EMG values measured using a powered screwdriver were on average 1 mA lower than values from a standard probe. When readings less than or equal to 20 mA were considered, the limits of agreement were approximately 4 and 7 mA overall. In total, 28/305 (9%) screws were removed and reinserted, 9/305 (3%) screws were redirected, and 3/305 (1%) screws were aborted based on t-EMG readings. Despite a small overall difference in t-EMG value between the standard probe and screwdriver, there was still large variability in agreement between the two techniques. t-EMG values obtained with a powered screwdriver during screw insertion are not interchangeable with values measured by a probe.
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Affiliation(s)
- Sumeet Garg
- Orthopedics, Children's Hospital Colorado , Aurora , Colorado
| | - Claire Palmer
- Department of Pediatrics, School of Medicine University of Colorado , Aurora , Colorado
| | - Wayne Whitmore
- Orthopedics, Children's Hospital Colorado , Aurora , Colorado
| | - Micaela Cyr
- Orthopedics, Children's Hospital Colorado , Aurora , Colorado
| | - Nicole Michael
- Orthopedics, Children's Hospital Colorado , Aurora , Colorado
| | - Eun Kim
- Orthopedics, Children's Hospital Colorado , Aurora , Colorado
| | - Willy Boucharel
- Orthopedics, Children's Hospital Colorado , Aurora , Colorado
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15
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Carlson BC, Milbrandt TA, Larson AN. Quality, Safety, and Value in Pediatric Spine Surgery. Orthop Clin North Am 2018; 49:491-501. [PMID: 30224010 DOI: 10.1016/j.ocl.2018.05.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The article addresses patient safety topics in spine surgery, including infection, length of stay, instrumentation strategies, pedicle screw malposition, radiation exposure, and neurologic events. Quality, safety, and value are concepts that are practical, easy to understand, and can be implemented on any scale and may be matched to individual practices. Further, with quality improvement, there is a culture shift to openly share information, protocols, and strategies so that more patients can rapidly benefit.
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Affiliation(s)
- Bayard C Carlson
- Department of Orthopedic Surgery, Mayo Clinic Rochester, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Todd A Milbrandt
- Department of Orthopedic Surgery, Mayo Clinic Rochester, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - A Noelle Larson
- Department of Orthopedic Surgery, Mayo Clinic Rochester, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA.
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16
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Shaw KA, Murphy JS, Devito DP. Accuracy of robot-assisted pedicle screw insertion in adolescent idiopathic scoliosis: is triggered electromyographic pedicle screw stimulation necessary? JOURNAL OF SPINE SURGERY 2018; 4:187-194. [PMID: 30069506 DOI: 10.21037/jss.2018.04.01] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Background Screw malpositioning is an identifiable cause of intraoperative neurophysiologic changes. Although triggered screw electromyography (t-EMG) has been found to exhibit high sensitivity for identifying malpositioned screws, no previous study has assessed the utility of combining t-EMG with robotic-assisted pedicle screw placement for identifying malpositioned screws. We sought to evaluate the utility of t-EMG used in combination with robotic-assisted pedicle screw placement for identifying malpositioned screws in patients with adolescent idiopathic scoliosis (AIS). Methods Patients undergoing robotic-assisted posterior spinal fusion with pedicle screw fixation for AIS underwent retrospective review from a single surgeons prospectively collected database. Preoperative demographic data and curve characteristics were recorded. Computed tomography (CT) scans were reviewed, measuring pedicle width and classifying pedicle morphology using the channel classification system. Pedicle data was compared against intra-operative t-EMG data, with a minimal threshold of 8 mA used for screw removal and screw path examination and the rate of screw re-direction recorded. All pedicle screws were verified using image intensification. Results Forty-nine patients (11 males, 38 females, average age 14.49 years) with an average curve magnitude of 51 degrees and placement of 844 pedicle screws to attain an average curve correction of 67.7%. The incidence of an absent pedicle (type C or D morphology) was 2%. Overall, 24 screws (2.8%) were identified with an abnormal t-EMG threshold. All screws were found to have an intact medial wall upon probing and were reinserted without re-direction. No patient or curve characteristic was predictive of abnormal t-EMG amplitude but smaller pedicles correlated with smaller amplitudes. Conclusions With precise pre-operative planning, robotic-assisted pedicle screw placement has shown to be a safe and effective method in treating AIS patients as shown by the lack of medial pedicle breach and malpositioned screws. We found no evidence to support combined use of t-EMG for identifying medially malpositioned screws.
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Affiliation(s)
- K Aaron Shaw
- Department of Orthopaedic Surgery, Dwight D. Eisenhower Army Medical Center, Fort Gordon, GA, USA
| | - Joshua S Murphy
- Department of Pediatric Orthopaedics, Children's Healthcare of Atlanta Scottish Rite, Atlanta, GA, USA
| | - Dennis P Devito
- Department of Pediatric Orthopaedics, Children's Healthcare of Atlanta Scottish Rite, Atlanta, GA, USA
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Nooh A, Lubov J, Aoude A, Aldebeyan S, Jarzem P, Ouellet J, Weber MH. Differences between Manufacturers of Computed Tomography-Based Computer-Assisted Surgery Systems Do Exist: A Systematic Literature Review. Global Spine J 2017; 7:83-94. [PMID: 28451513 PMCID: PMC5400166 DOI: 10.1055/s-0036-1583942] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 03/21/2016] [Indexed: 11/26/2022] Open
Abstract
STUDY DESIGN Literature review. OBJECTIVE Several studies have shown that the accuracy of pedicle screw placement significantly improves with use of computed tomography (CT)-based navigation systems. Yet, there has been no systematic review directly comparing accuracy of pedicle screw placement between different CT-based navigation systems. The objective of this study is to review the results presented in the literature and compare CT-based navigation systems relative only to screw placement accuracy. METHODS Data sources included CENTRAL, Medline, PubMed, and Embase databases. Studies included were randomized clinical trials, case series, and case-control trials reporting the accuracy of pedicle screws placement using CT-based navigation. Two independent reviewers extracted the data from the selected studies that met our inclusion criteria. Publications were grouped based on the CT-based navigation system used for pedicle screw placement. RESULTS Of the 997 articles we screened, only 26 met all of our inclusion criteria and were included in the final analysis, which showed a significant statistical difference (p < 0.0001, 95% confidence interval 0.92 to 1.23) in accuracy of pedicle screw placement between three different CT-based navigation systems. The mean (weighted) accuracy of pedicle screws placement based on the CT-based navigation system was found to be 97.20 ± 2.1% in StealthStation (Medtronic, United States) and 96.1 ± 3.9% in VectorVision (BrainLab, Germany). CONCLUSION This review summarizes results presented in the literature and compares screw placement accuracy using different CT-based navigation systems. Although certain factors such as the extent of the procedure and the experience and skills of the surgeon were not accounted for, the differences in accuracy demonstrated should be considered by spine surgeons and should be validated for effects on patients' outcome.
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Affiliation(s)
- Anas Nooh
- McGill Scoliosis and Spine Centre, McGill University Health Centre, Montreal, Canada
- Department of Orthopedic Surgery, King Abdulaziz University, Jeddah, Saudi Arabia
- These authors contributed equally to this article
| | - Joushua Lubov
- McGill Scoliosis and Spine Centre, McGill University Health Centre, Montreal, Canada
- These authors contributed equally to this article
| | - Ahmed Aoude
- McGill Scoliosis and Spine Centre, McGill University Health Centre, Montreal, Canada
| | - Sultan Aldebeyan
- McGill Scoliosis and Spine Centre, McGill University Health Centre, Montreal, Canada
- Department of Orthopedic Surgery, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Peter Jarzem
- McGill Scoliosis and Spine Centre, McGill University Health Centre, Montreal, Canada
| | - Jean Ouellet
- McGill Scoliosis and Spine Centre, McGill University Health Centre, Montreal, Canada
| | - Michael H. Weber
- McGill Scoliosis and Spine Centre, McGill University Health Centre, Montreal, Canada
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