1
|
Zhang Z, Zhao Y, Chou D, Zhang S, Zhou R, Ma Z, Wang L, Yu Z, Liu Y, Wang Y. Study on articular surface morphology of atlantoaxial lateral mass based on differential manifold. J Orthop Surg Res 2023; 18:919. [PMID: 38042858 PMCID: PMC10693051 DOI: 10.1186/s13018-023-04410-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 11/26/2023] [Indexed: 12/04/2023] Open
Abstract
OBJECTIVES To propose a surface reconstruction algorithm based on a differential manifold (a space with local Euclidean space properties), which can be used for processing of clinical images and for modeling of the atlantoaxial joint. To describe the ideal anatomy of the lateral atlantoaxial articular surface by measuring the anatomical data. METHODS Computed tomography data of 80 healthy subjects who underwent cervical spine examinations at our institution were collected between October 2019 and June 2022, including 46 males and 34 females, aged 37.8 ± 5.1 years (28-59 years). A differential manifold surface reconstruction algorithm was used to generate the model based on DICOM data derived by Vision PACS system. The lateral mass articular surface was measured and compared in terms of its sagittal diameter, transverse diameter, articular surface area, articular curvature and joint space height. RESULTS There was no statistically significant difference between left and right sides of the measured data in normal adults (P > 0.05). The atlantoaxial articular surface sagittal diameter length was (15.83 ± 1.85) and (16.22 ± 1.57) mm on average, respectively. The transverse diameter length of the articular surface was (16.29 ± 2.16) and (16.49 ± 1.84) mm. The lateral articular surface area was (166.53 ± 7.69) and (174.48 ± 6.73) mm2 and the curvature was (164.03 ± 5.27) and (153.23 ± 9.03)°, respectively. The joint space height was 3.05 ± 0.11mm, respectively. There is an irregular articular space in the lateral mass of atlantoaxial, and both upper and lower surfaces of the articular space are concave. A sagittal plane view shows that the inferior articular surface of the atlas is mainly concave above; however, the superior articular surface of the axis is mainly convex above. In the coronal plane, the inferior articular surface of the atlas is mostly concave above, with most concave vertices located in the medial region, and the superior articular surface of the axis is mainly concave below, with most convex vertices located centrally and laterally. CONCLUSION A differential manifold algorithm can effectively process atlantoaxial imaging data, fit and control mesh topology, and reconstruct curved surfaces to meet clinical measurement applications with high accuracy and efficiency; the articular surface of the lateral mass of atlantoaxial mass in normal adults has relatively constant sagittal diameter, transverse diameter and area. The distance difference between joint spaces is small, but the shape difference of articular surfaces differs greatly.
Collapse
Affiliation(s)
- Zeyuan Zhang
- Department of the Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Zhengzhou, 450052, China
| | - Yao Zhao
- Department of the Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Zhengzhou, 450052, China
| | - Dean Chou
- Department of the Neurosurgery, Columbia University, New York, USA
| | - Shuhao Zhang
- Department of the Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Zhengzhou, 450052, China
| | - Ruifang Zhou
- School of Mathematics and Information Sciences, Zhongyuan University of Technology, Zhengzhou, China
| | - Zeyu Ma
- School of Mathematics and Information Sciences, Zhongyuan University of Technology, Zhengzhou, China
| | - Limin Wang
- Department of the Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Zhengzhou, 450052, China
| | - Zhong Yu
- Department of the Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Zhengzhou, 450052, China
| | - Yilin Liu
- Department of the Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Zhengzhou, 450052, China.
| | - Yuqiang Wang
- Department of the Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Zhengzhou, 450052, China.
| |
Collapse
|
2
|
Raut S, Kundnani VG, Meena MK, Patel JY, Asati S, Patel A. Anthropometric evaluation for surgical feasibility of C1-C2 transarticular screw stabilization in Indian population. JOURNAL OF CRANIOVERTEBRAL JUNCTION AND SPINE 2021; 12:129-135. [PMID: 34194158 PMCID: PMC8214229 DOI: 10.4103/jcvjs.jcvjs_175_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 01/18/2021] [Indexed: 11/05/2022] Open
Abstract
Study Design: This study was a radiographic observational study for C1–C2 anthropometry. Purpose: The purpose of the study was to understand the anatomic relationship of C1–C2 in view of transarticular screw (TAS) fixation, to overcome the difficulties related with TAS placement, and to minimize the technique-related complications. Materials and Methods: It was an anthropometric observational study with retrospectively obtained anatomical data of randomly selected 116 patients from a single center. The anatomical measurements such as pars width, pars height, screw trajectory, and length were evaluated on the axial, sagittal, and three-dimensional reconstructed cervical CT scan using the radiant DICOM viewer software by the two fellowship trained spine surgeons which were blind to the study group details. The intra- and interobserver reliability with regard to the measured parameters was statistically analyzed. Results: The mean age of male and female was 28 and 29 years. The average BMI was calculated to be 23.5 and 25 for males and females, respectively. The mean right pars width in males was 5.78 ± 0.93 (range: 3.1–6.5 mm), while in female, it was 5.84 ± 0.95 (range: 3.1–6.5). The mean left pars width in males was 5.95 ± 1.13 (range: 3.8–8.1 mm), while in females, it was 5.70 ± 1.18 (range: 3.7–8.1 mm). Right side mean pars height in males was 5.90 ± 1.2 (range: 3.7–9.4 mm), and in females, it was 6.11 ± 1.04 (range: 3.8–9.3 mm). Left-sided mean pars height in males was 6.0 ± 1.1 (range: 3.2–9.4 mm) as compared to females, in which it was 5.77 ± 1.23 (range: 4.1–9.3 mm). The mean lateral angulation angle in males was 9.99° ± 1.70° (8.1°–15°), while in females, it was 10.15° ± 1.73° (8.1°–15°). The mean sagittal angulation in males was 26.33° ± 3.32° (21.0°–32.80°), while in females, it was 27.18 ± 3.05 (21.0°–32.10°). The average screw length in males was 41.74 ± 5.63 (34–54.8 mm), whereas in females, it was 41.35 ± 4.77 (34–54.8 mm). Conclusion: This study provides a morphometric database which is characteristic of the C1–C2 vertebrae in the normal Indian population with regard to the anatomic feasibility of the TAS fixation for various C1–C2 pathologies. The C2 pars width and height measured in the current study can guide the selection of TAS screws in the Indian population. This study could serve in providing the baseline anatomic parameters assessed in the healthy individuals to design and develop customized screws and related implant assembly which might provide wider clinical applicability.
Collapse
Affiliation(s)
- Saijyot Raut
- Department of Orthopaedics, Bombay Hospital and Medical Research Centre, Mumbai, Maharashtra, India
| | - Vishal G Kundnani
- Department of Orthopaedics, Bombay Hospital and Medical Research Centre, Mumbai, Maharashtra, India
| | - Mohit Kumar Meena
- Department of Orthopaedics, Bombay Hospital and Medical Research Centre, Mumbai, Maharashtra, India
| | - Jwalant Y Patel
- Department of Orthopaedics, Bombay Hospital and Medical Research Centre, Mumbai, Maharashtra, India
| | - Sanjeev Asati
- Department of Orthopaedics, Bombay Hospital and Medical Research Centre, Mumbai, Maharashtra, India
| | - Ankit Patel
- Department of Orthopaedics, Bombay Hospital and Medical Research Centre, Mumbai, Maharashtra, India
| |
Collapse
|
3
|
Estillore RP, Buchowski JM, Minh DV, Park KW, Chang BS, Lee CK, Riew KD, Yeom JS. Risk of internal carotid artery injury during C1 screw placement: analysis of 160 computed tomography angiograms. Spine J 2011; 11:316-23. [PMID: 21474083 DOI: 10.1016/j.spinee.2011.03.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Accepted: 03/08/2011] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Injury to the internal carotid artery (ICA) is a potentially catastrophic complication of C1-lateral mass (C1-LM) or C1-C2 transarticular screw insertion. PURPOSE This study was designed to determine the risk of injury to the ICA during placement of these screws using computed tomography angiography (CTA). STUDY DESIGN Radiographic analysis using CTA. PATIENT SAMPLE One hundred sixty CTAs were examined, for a total of 320 ICAs. OUTCOME MEASURES Not applicable. METHODS Fine-cut intravenous CTAs with multiplanar and three-dimensional reconstruction were reviewed. The position of the ICA in relation to the anterior cortex (AC) of C1, anterior end of the anterior tubercle (AT), and medial margin of the transverse foramen (TF) was measured bilaterally in three ascending and equidistant levels of the C1-AT. RESULTS The position of the ICA in relation to C1 was variable. The average distance between the ICA and the AC of C1 was only 3.7 mm. Furthermore, 96% of the time the posterior margin of the ICA was located posterior to the anteriormost aspect of the anterior C1 tubercle (average distance, 5.4 mm), making the ICA vulnerable to damage if a drill, tap, or screw was inserted to the depth of the anteriormost portion of the AT as seen on a lateral fluoroscopic or radiographic view. The medial margin of the ICA was located medial to the TF (a location potentially vulnerable to injury with bicortical screw placement) less often at the caudal aspect of the C1-AT (54%) than at its middle or cranial aspect (74% and 75%, respectively). No ICAs were located anterior to the medial 30% of the C1-LM or more medially. CONCLUSIONS Bicortical C1-LM or C1-C2 transarticular screw placement carries a potential risk of ICA injury. Given the wide variation in ICA location relative to C1, if bicortical C1 fixation is required, preoperative CTA should be considered to determine the optimal screw trajectory. In general, inferomedially angulated C1-LM screws appear to be safer with respect to the ICA injury than other potential trajectories.
Collapse
Affiliation(s)
- Romel P Estillore
- Spine Center and Department of Orthopaedic Surgery, Seoul National University College of Medicine and Seoul National University Bundang Hospital, 166 Gumiro, Bundang-ku, Sungnam 463-707, Republic of Korea
| | | | | | | | | | | | | | | |
Collapse
|
4
|
Wait SD, Ponce FA, Colle KO, Parry PV, Sonntag VK. IMPORTANCE OF THE C1 ANTERIOR TUBERCLE DEPTH AND LATERAL MASS GEOMETRY WHEN PLACING C1 LATERAL MASS SCREWS. Neurosurgery 2009; 65:952-6; discussion 956-7. [DOI: 10.1227/01.neu.0000350156.20774.ac] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
5
|
Anatomical study of axis for odontoid screw thickness, length, and angle. 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 2008; 18:271-5. [PMID: 19005694 DOI: 10.1007/s00586-008-0814-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Revised: 09/16/2008] [Accepted: 10/12/2008] [Indexed: 10/21/2022]
Abstract
Anterior odontoid screw fixation is a safe and effective method for treatment of odontoid fractures. The screw treads should fit into the odontoid medulla, should pass the fracture line, and should pull fractured odontoid tip against body of axis in order to achieve optimum screw placement and treatment. This study has demonstrated optimal anterior odontoid screw thickness, length, and optimal angle for safe and strong anterior odontoid screw placement. Dry bone axis vertebrae were evaluated by direct measurements, X-ray measurements, and computerized tomography (CT) measurements. The screw thickness (inner diameter of the odontoid) was measured as well as screw length (distance between anterior-inferior point body of axis and tip of odontoid), and screw angle (the angle between basis of axis and tip of odontoid). The inner diameter of odontoid bone was measured as 6.5+/-1.9 mm, the screw length was 37.6+/-3.3 mm, and the screw angle was 62.4+/-4.7 on CT. There was no statistical difference between X-ray and CT in the measurements of screw thickness and angle. X-ray and CT measurements are both safe methods to determine the inner odontoid diameter and angle preoperatively. Screw length should be measured on CT only. To provide safe and strong anterior odontoid screw fixation, screw thickness, length, and angle should be known preoperatively, and these can be measured on X-ray and CT.
Collapse
|
6
|
Insertion of lateral mass screw of the atlas via the posterior arch: anatomical study of screw insertion using dry bone samples of the atlas from Japanese cadavers. J Orthop Sci 2008; 13:452-5. [PMID: 18843460 DOI: 10.1007/s00776-008-1255-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Accepted: 05/08/2008] [Indexed: 10/21/2022]
Abstract
BACKGROUND A new technique involving screw fixation of the atlas via the posterior arch and lateral mass has recently been reported for atlantoaxial instability. Because the posterior arch is thin, lateral mass screws risk penetrating the upper part of the posterior arch and damaging the vertebral artery running along the upper part of the posterior arch. METHODS A total of 50 dry bone samples of the atlas from Japanese cadavers were used. We manually measured the shortest distance from the vertebral canal to the transverse foramen and the thickness at the thinnest part of the groove using calipers and investigated the frequency of dorsal ponticuli at the posterior arch. RESULTS The area from the vertebral canal to the transverse foramen was thick enough to allow screw insertion, but the thickness of the posterior arch at the thinnest part of the groove was less than the screw diameter (3.5 mm) in 22% of vertebrae and <4 mm in 39%. A dorsal ponticuli was present in 10% of these samples. CONCLUSIONS The size and shape of the posterior arch must be evaluated using radiography and computed tomography before inserting a lateral mass screw of the atlas via the posterior arch.
Collapse
|
7
|
Cyr SJ, Currier BL, Eck JC, Foy A, Chen Q, Larson DR, Yaszemski MJ, An KN. Fixation strength of unicortical versus bicortical C1-C2 transarticular screws. Spine J 2008; 8:661-5. [PMID: 17526435 DOI: 10.1016/j.spinee.2007.02.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2006] [Revised: 02/07/2007] [Accepted: 02/08/2007] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT The internal carotid artery and hypoglossal nerve lie over the anterior aspect of the lateral mass of the atlas and are at risk from bicortical C1-C2 transarticular screws. This has led to the recommendation for unicortical screws if the neurovascular structures are in close proximity to the proposed exit point. No data are available on strength of unicortical versus bicortical C1-C2 transarticular screws. PURPOSE To compare the biomechanical pullout strength of unicortical versus bicortical C1-C2 transarticular screws in a cadaveric model. STUDY DESIGN Biomechanical study. METHODS Fifteen cervical spine specimens underwent axial pullout testing. A unicortical C1-C2 transarticular screw was placed on one side with a contralateral bicortical screw. Data were analyzed to reveal any significant differences in strength. RESULTS Mean pullout strength for the bicortical C1-C2 transarticular screws was 1,048.8 (+/-360.1) N versus 939.2 (+/-360.6) for unicortical screws (p=.22). There was no significant difference in the pullout strength of unicortical and bicortical screws. CONCLUSIONS In cases with satisfactory bone quality, it appears reasonable to use unicortical screws to avoid the risk of neurovascular injury from penetrating the anterior cortex of C1.
Collapse
Affiliation(s)
- Steven J Cyr
- Department of Orthopedic Surgery, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Hoh DJ, Maya M, Jung A, Ponrartana S, Lauryssen CL. Anatomical relationship of the internal carotid artery to C-1: clinical implications for screw fixation of the atlas. J Neurosurg Spine 2008; 8:335-40. [DOI: 10.3171/spi/2008/8/4/335] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Various C1–2 instrumentation techniques have been developed to treat atlantoaxial instability. Screw fixation of C1–2 poses a risk of injury to the vertebral artery and internal carotid artery (ICA). Injury to the ICA caused by C-1 screws is extremely rare, but has been described. To characterize this risk, the authors studied the anatomical relationship of the ICA to the lateral mass of C-1.
Methods
The authors studied 100 patients who had undergone computed tomography scanning and magnetic resonance imaging of the neck to assess the position of the ICA in association with the C-1 lateral mass. Each ICA was classified into 1 of the following 4 zones: Zone 1 (medial to lateral mass), Zone 2 (medial half of lateral mass), Zone 3 (lateral half of lateral mass), and Zone 4 (lateral to lateral mass). For patients with an ICA ventral to the lateral mass, the shortest distance between the ICA and lateral mass was measured to determine the margin of error with an overpenetrated bicortical screw.
Results
Of the 100 patients, 58% had a left ICA in Zones 2 and 3 with a mean distance from the anterior cortex of 3.5 ± 1.5 mm (± standard deviation), and 74% had a right ICA in Zones 2 and 3 with a mean distance from the anterior cortex of 3.9 ± 1.6 mm. Both ICAs anterior to the lateral mass were noted in 47% of patients, and 84% had ≥ 1 ICA anterior to the lateral mass. When the ICA was anterior to the lateral mass, it was more commonly in the lateral half (left ICA in 91% and right ICA in 92%). The left ICA was in Zone 1 in 1% and Zone 4 in 41%. The right ICA was in Zone 1 in 1% and Zone 4 in 25%.
Conclusions
A high percentage of patients demonstrate an ICA directly ventral to the C-1 lateral mass, which poses a risk of ICA injury caused by an overpenetrated bicortical screw.
Collapse
Affiliation(s)
- Daniel J. Hoh
- 1Department of Neurological Surgery, University of Southern California
| | - Marcel Maya
- 2Department of Neuroradiology, Cedars–Sinai Medical Center, Los Angeles; and
| | - Alexander Jung
- 2Department of Neuroradiology, Cedars–Sinai Medical Center, Los Angeles; and
| | - Skorn Ponrartana
- 2Department of Neuroradiology, Cedars–Sinai Medical Center, Los Angeles; and
| | | |
Collapse
|
9
|
Nogueira-Barbosa MH, Defino HLA. Multiplanar reconstructions of helical computed tomography in planning of atlanto-axial transarticular fixation. 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 2005; 14:493-500. [PMID: 15754214 PMCID: PMC3454655 DOI: 10.1007/s00586-004-0838-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2004] [Accepted: 10/03/2004] [Indexed: 10/25/2022]
Abstract
The objective of this study was to determine atlanto-axial bone morphometric measurements related to screw transarticular fixation technique. One hundred helical computerized tomography (helical CT) scans with volumetric acquisition, including the first and the second cervical vertebrae, were studied. The screw insertion axis according to the Magerl technique for C1-C2 transarticular fixation was the referential to select the correct oblique axial and oblique parasagittal planes obtained with multiplanar reconstruction (MPR) on helical CT. The selected measured parameters on each side of the vertebrae were C2 interarticular isthmus height and width, optimal screw length, optimal screw trajectory sagittal and axial angles, and the distance between the ideal screw trajectory and the vertebral artery groove. C2 interarticular isthmus height measured 7.75+/-1.27 mm, C2 interarticular isthmus width 7.94+/-1.72 mm, optimal screw length 39.03+/-2.81 mm, optimal screw trajectory sagittal angle 57.54+/-5.28 degrees , optimal screw trajectory medial angle 7.90+/-4.05 degrees. Isthmus narrowing under 5 mm (height and/or width) was seen in 5% of cases. In 30% of cases reconstructed parasagittal images showed the vertebral artery groove. In those cases, the distance between the vertebral artery groove and the ideal screw path was measured. This distance measured under 2.5 mm in 7% of C2 articular masses. A classification of C2 articular mass morfology was proposed. The C2 articular masses without anatomic variations predisposing to vertebral artery injury were considered type I. The C2 articular masses potentially associated with vascular injury (12%) were classified as type II. Potential risk was identified at the C2 isthmus only (3%), at the anterior portion of C2 articular mass only (7%) or at both regions (2%). According to selected criteria 18% of patients would have at least one side C2 articular mass with potential risk for the vertebral artery. In 6% of patients the potential risk was identified bilaterally. There is a great variation in the maximum and minimum values of the anatomic measurements. Therefore preoperative CT scans are very important to identify type II cases, such that the surgeon may preoperatively define the bony anatomy trough which the screws will pass.
Collapse
Affiliation(s)
- M H Nogueira-Barbosa
- Radiology Division, Faculty of Medicine of Ribeirao Preto, HCFMRP, University of São Paulo, Av. Bandeirantes, 3900, Campus Universitàrio, Ribeirao Preto, Sao Paulo, Brazil 14048-900.
| | | |
Collapse
|
10
|
Richter M, Mattes T, Cakir B. Computer-assisted posterior instrumentation of the cervical and cervico-thoracic spine. 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 2004; 13:50-9. [PMID: 14634850 PMCID: PMC3468035 DOI: 10.1007/s00586-003-0604-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2002] [Revised: 07/03/2003] [Accepted: 07/18/2003] [Indexed: 10/26/2022]
Abstract
Posterior instrumentation of the cervical spine has become increasingly popular in recent years. Dissatisfaction with lateral mass fixation, especially at the cervico-thoracic junction, has led spine surgeons to use pedicle screws. The improved biomechanical stability of pedicle screws and transarticular C1/2 screws allows for shorter instrumentations and improves the repositioning possibilities. Nevertheless, there are potential risks of iatrogenic damage to the spinal cord, nerve roots or the vertebral artery with both techniques. Therefore, the aim of this study was to evaluate whether C1/2 transarticular screws and transpedicular screws can be applied safely and with high accuracy in the cervical spine and the cervico-thoracic junction using a computer-assisted surgery system (CAS system). Posterior instrumentation was performed using the Brainlab VectorVision System (BrainLAB, Heimstetten, Germany) in 19 patients. Surface matching was used for registration. We placed 22 transarticular screws C1/2, 31 cervical pedicle screws, 10 high thoracic pedicle screws and one lateral mass screw C1. The screw position was evaluated postoperatively using CT with multiplanar reconstruction in the screw axis of each screw. None of the transarticular screws or pedicle screws was significantly (>2 mm) misplaced and no screw-related injury to vascular, neurogenic or bony structures was observed. No screw revision was necessary. The mean operation time was 144 min (90-240 min) and the mean blood loss was 234 ml (50-800 ml). C1/2 transarticular screws, as well as transpedicular screws in the cervical spine and the cervico-thoracic junction, can be applied safely and with high accuracy using a CAS system. Computer-assisted instrumentation is recommended especially for pedicle screws at C3-C6.
Collapse
Affiliation(s)
- Marcus Richter
- Department of Orthopaedics, University of Ulm, Ulm, Germany.
| | | | | |
Collapse
|
11
|
Igarashi T, Kikuchi S, Sato K, Kayama S, Otani K. Anatomic study of the axis for surgical planning of transarticular screw fixation. Clin Orthop Relat Res 2003:162-6. [PMID: 12616054 DOI: 10.1097/00003086-200303000-00020] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Transarticular screw fixation has shown increased stability compared with other posterior stabilization techniques. However, there have been few reports on vertebral artery injury related to the screw insertion. The current study measured the parameters of the pedicle and vertebral artery groove of the axis and clarified the accuracy and safety of the transarticular screw fixation. Direct measurements were taken from 98 dry axis vertebrae. The width and height of the pedicle were measured. The mediolateral and anteroposterior dimensions of the vertebral artery groove also were measured. Forty-one percent had asymmetry. In 20% of the specimens, the pedicle was smaller than the diameter of the screw (3.5 mm). The pedicle of the axis has large anatomic variability and asymmetry. Some pedicles were not suitable for atlantoaxial transarticular screw fixation. The risks associated with screw fixation should be prevented by preoperative computed tomography with three-dimensional reconstruction. Screw trajectory reconstruction with coronal and sagittal reconstruction is useful to evaluate the pedicle width and height.
Collapse
Affiliation(s)
- Tamaki Igarashi
- Department of Orthopaedic Surgery, Fukushima Medical University, School of Medicine, Fukushima City, Japan.
| | | | | | | | | |
Collapse
|
12
|
Weidner A, Wähler M, Chiu ST, Ullrich CG. Modification of C1-C2 transarticular screw fixation by image-guided surgery. Spine (Phila Pa 1976) 2000; 25:2668-73; discussion 2674. [PMID: 11034654 DOI: 10.1097/00007632-200010150-00020] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN This is a feasibility study of image-guided surgery for C1-C2 transarticular screw fixation comparing postoperative screw position in a nonrandomized prospective cohort with a historic control group in which fluoroscopic guidance was used alone. OBJECTIVES To evaluate the potential benefits and disadvantages of image-guided surgery for C1-C2 screw placement. SUMMARY OF BACKGROUND DATA C1-C2 transarticular screw fixation is biomechanically superior to other current surgical stabilization procedures. The original technique for C1-C2 screw placement relies on anatomic landmarks and intraoperative fluoroscopy. Screw misplacement or anatomic variations can result in vertebral artery injury. Image-guided surgery involves using computed tomography (CT) data to plan the optimal screw trajectory before surgery and then use this data to guide screw placement during the actual surgery. Promising results of this technique are reported in the literature, but no direct comparison between image-guided surgery and conventional surgical techniques has been previously reported. METHODS The image-guided surgery group consisted of 37 prospective patients. The historic control group included 78 patients who had similar surgeries performed using only fluoroscopic guidance. For the image-guided surgery group, subluxation was reduced by positioning at the time of CT examination. The CT data were transferred to a StealthStation (Sofamor-Danek, Memphis, TN) surgical planning and guidance computer system, and an optimal screw trajectory was determined for the right and left transarticular screws. After matching the surgical field to the virtual computer field, C2 was drilled according to the planned screw trajectory, and screws were placed. Plain radiographs and CT were used for postoperative evaluation of the image-guided surgery group. RESULTS Image-guided surgery reduced but did not eliminate the risk of screw misplacement. Surgical time was not increased overall. CONCLUSIONS Image-guided surgery is an effective tool for the achievement of correct screw placement in C1-C2 transarticular screw fixation procedures. The procedure remains technically demanding.
Collapse
Affiliation(s)
- A Weidner
- Spine Center Osnabrück, Osnabrück, Germany.
| | | | | | | |
Collapse
|
13
|
Abstract
STUDY DESIGN The accuracy and safety of atlantoaxial transarticular screw insertion were evaluated in clinical cases. OBJECTIVES To evaluate the accuracy and safety of atlantoaxial transarticular screw insertion under lateral fluoroscopic monitoring without opening the joint. SUMMARY OF BACKGROUND DATA Atlantoaxial transarticular screw fixation has been reported to be biomechanically superior to posterior atlantoaxial wiring techniques. Several clinical series have been reported in the literature. In some reports, the risk of screw insertion in this technique has been pointed out. MATERIALS AND METHODS Fifty-six consecutive patients with atlantoaxial instability were treated by transarticular screw fixation. One hundred twelve screw insertions in these 56 patients were assessed by surgical record and computed tomographic examination. One screw could not be inserted because of the difficulty of adequate placement during operation; 111 screws were therefore inserted. Adequate position was defined as when the screw perforated the lateral atlantoaxial joint. RESULTS In this series, neither vertebral artery injury nor spinal cord injury was experienced clinically. One guide wire was broken during drilling with a cannulated drill. Computed tomographic examination demonstrated that 106 screws perforated the atlantoaxial joint. Therefore, 95.5% of screws were adequately positioned. There were two screws positioned lateral to the joint, two medially, and one anteroinferiorly to the joint. CONCLUSIONS Atlantoaxial transarticular screw insertion using image intensifier without opening the lateral joint was performed safely, but not accurately, in all cases.
Collapse
Affiliation(s)
- T Fuji
- Department of Orthopaedic Surgery, Osaka Prefectural Hospital, Osaka, Japan.
| | | | | | | | | |
Collapse
|