High riding vertebral artery

Jin S. YeomJacob M.

Vertebral artery injury VAI is a known potential complication of both anterior and posterior cervical spine surgery. VAI can occur during soft tissue dissection, retraction, foraminotomy, drilling or instrumentation placement. The most common causes of injury have been reported to be drilling and instrumentation 1. Placement of transarticular C1—C2 screws as well as C2 pars and C2 pedicle screws carries substantial risk of injury to the vertebral artery, with some reports as high as 8. The immediate neurologic signs and symptoms of VAI can include pseudoaneurysm, arteriovenous AV fistula, cerebral infarction, root damage or death. To mitigate the risk of iatrogenic VAI, pre-operative computed tomography CT or magnetic resonance imaging MRI angiography should be used to assess the position of the vertebral artery throughout its course in the cervical spine.

High riding vertebral artery

Rheumatoid arthritis RA might lead to atlantoaxial instability requiring transpedicular or transarticular fusion. High-riding vertebral artery HRVA puts patients at risk of injuring the vessel. However, to date, no relative risk RR has been calculated in order to quantitatively determine a true impact of RA as its risk factor. To the best of our knowledge, this is the first attempt to do so. RA patients were qualified into the exposed group group A , whereas non-RA subjects into the unexposed group group B. Risk of bias was explored by means of Newcastle-Ottawa Scale. MOOSE checklist was followed to ensure correct structure. Fixed-effects model inverse variance was employed. Four studies with a total of subjects were included in meta-analysis. One hundred twenty-five subjects were in group A; subjects were in group B. Mean age in group A was 62,1 years, whereas in group B 59,9 years. Rheumatoid arthritis is associated with over twofold risk of developing HRVA, and therefore, vertebral arteries should be meticulously examined preoperatively before performing craniocervical fusion in every RA patient. Luthman, J.

InPatkar et al.

Metrics details. This study aims to investigate the clinical application and feasibility of C2 subfacetal screws in patients with Klippel-Feil syndrome KFS , narrow C2 pedicles, and high-riding vertebral arteries HRVAs. The clinical data of seven patients with KFS, atlantoaxial dislocation, narrow C2 pedicles, and HRVAs treated with C2 subfacetal screws were analyzed in this retrospective study. The internal height, isthmus height, and pedicle width of C2 vertebra were measured using preoperative computed tomography CT. Subfacetal screws were inserted for 7 patients 12 sides. The position and length of the screws were observed using postoperative CT. Intraoperative dura mater and vertebral artery VA injuries were recorded.

At the time the article was last revised Rohit Sharma had no financial relationships to ineligible companies to disclose. The vertebral arteries VA are paired arteries, each arising from the respective subclavian artery and ascending in the neck to supply the posterior fossa and occipital lobes, as well as provide segmental vertebral and spinal column blood supply. The origin of the vertebral arteries is usually from the posterior superior part of the subclavian arteries bilaterally, although the origin can be variable:. When the origin is from the arch, then it is common for the artery to enter the foramen transversarium at a level higher than normal C5 instead of C6. Rarely, the right vertebral artery can have an aberrant origin distal to the left subclavian; see vertebral arteria lusoria. The vertebral artery is typically divided into 4 segments :. Also known as the extraosseous segment, V1 arises from the first part of the subclavian artery. It angles posteriorly between longus colli medially and scalenus anterior laterally, through the colliscalene triangle , and behind the common carotid artery to enter the transverse foramen of C6. V2 ascends through the transverse foramina of the cervical vertebrae, normally C6-C3.

High riding vertebral artery

High-riding vertebral artery HRVA and narrow C2 pedicles C2P pose a great risk of injuring the vessel during C2 pedicle or transarticular screw placement. Recent meta-analysis revealed a paucity of European studies regarding measurements and prevalence of these anatomical variants. Three hundred eighty-three consecutive cervical spine CT scans with potential screw insertion sites were analyzed independently by two trained observers. Kappa statistics for inter- and intraobserver reliability as well as for inter-software agreement were calculated. Significant differences were found between females and males for all measurements. Each parameter showed either good or excellent inter- or intraobserver, and inter-software agreement coefficients. HRVA and narrow C2P are common findings in Central-European population and should be appreciated at the planning stage before craniocervical instrumentation. Measurements can be consistently reproduced by various observers at varying intervals using different software. Craniocervical junction CCJ is considered a tiger land in neurosurgery.

Kaybooz

It angles posteriorly between longus colli medially and scalenus anterior laterally, through the colliscalene triangle , and behind the common carotid artery to enter the transverse foramen of C6. All patients had HRVAs and narrow pedicles. Therefore, this study aims to provide a response to that relevant remark, aiding the body of neurosurgical literature. Reprints and permissions. Loading more images AP, anteroposterior. Inter-software agreement between Syn. The height of the isthmus is 3 mm. The clinical features of these patients are summarized in Table 1. Morphologic considerations of C2 isthmus dimensions for the placement of transarticular screws. In: Spine Journal. This study aims to investigate the clinical application and feasibility of C2 subfacetal screws in patients with Klippel-Feil syndrome KFS , narrow C2 pedicles, and high-riding vertebral arteries HRVAs. The left C2 pars screw was placed without complication. J Orthop Surg Res 17 , Electronic supplementary material.

Rheumatoid arthritis RA might lead to atlantoaxial instability requiring transpedicular or transarticular fusion.

The screw was inserted medially as far as possible. Choose 5. Second, because of the entry point of the C2 subfacetal screw close to the articular surface and the caudal tilted trajectory, the cage should be inserted first, and thereafter, the screw should be inserted. Conclusion The prevalence of a HRVA in patients with subaxial cervical spine disorders is higher than in those without and osteoarthritis of the C facet joints correlates significantly with a HRVA. Methods The clinical data of seven patients with KFS, atlantoaxial dislocation, narrow C2 pedicles, and HRVAs treated with C2 subfacetal screws were analyzed in this retrospective study. Conclusions The prevalence of a HRVA in patients with subaxial cervical spine disorders is higher than in those without and osteoarthritis of the C facet joints is correlated with a HRVA. Acknowledgements None. The selected entry point was approximately 3 to 4 mm below the midpoint of the posterior edge of the superior articular surface and parallel to the superior articular surface or slightly downward. Post-operative management following iatrogenic injury. Gianni Boris Bradac. After correction of vertical dislocation during the operation, the C 2 pedicle screw insertion and occipitocervical fixation and fusion were performed using the vertebral artery mobilization technique.