Atlantoaxial Transarticular Screw Fixation for a High-Riding Vertebral Artery

Neo, Masashi; Matsushita, Masafumi; Iwashita, Yasushi; Yasuda, Tadashi; Sakamoto, Takeshi; Nakamura, Takashi

doi:10.1097/01.brs.0000051919.14927.57

Cited by 101 publications

(70 citation statements)

References 25 publications

(53 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Atlantoaxial transarticular screw fixation combined with posterior bone graft has established itself as a reliable surgical management for atlantoaxial subluxation [5,7,8] with a few serious problems, including intraoperative vascular impairments [17,18] and non-union of bone grafts between C1 and C2 spinous processes and/or non-fused C1-C2 facets [10]. However, only a few of the late complications have been reported, one of which is subaxial sagittal alignment change [11,15,23].…”

Section: Discussionmentioning

confidence: 99%

“…In cases when we used an atlas claw to fix the C1-C2 arches, only bone chips were grafted. The detail of the overall surgical techniques has been described elsewhere [17,19].…”

Section: Methodsmentioning

confidence: 99%

“…However, this operation has its own risks, notably one of which is an intraoperative injury to the vertebral artery [17,18]. Another early complication could be non-union of either the atlantoaxial facets or the posterior bone graft, if combined, and we recently reported that this complication largely depends on the RA status of the patient and the material used for the posterior bone graft fixation [10].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Subaxial subluxation after atlantoaxial transarticular screw fixation in rheumatoid patients

et al. 2009

Self Cite

View full text Add to dashboard Cite

The most common cervical abnormality associated with rheumatoid arthritis (RA) is atlantoaxial subluxation, and atlantoaxial transarticular screw fixation has proved to be one of the most reliable, stable fixation techniques for treating atlantoaxial subluxation. Following C1-C2 fixation, however, subaxial subluxation reportedly can bring about neurological deterioration and require secondary operative interventions. Rheumatoid patients appear to have a higher risk, but there has been no systematic comparison between rheumatoid and nonrheumatoid patients. Contributing radiological factors to the subluxation have also not been evaluated. The objective of this study was to evaluate subaxial subluxation after atlantoaxial transarticular screw fixation in patients with and without RA and to find contributing factors. Fortythree patients who submitted to atlantoaxial transarticular screw fixation without any concomitant operation were followed up for more than 1 year. Subaxial subluxation and related radiological factors were evaluated by functional X-ray measurements. Statistical analyses showed that aggravations of subluxation of 2.5 mm or greater were more likely to occur in RA patients than in non-RA patients over an average of 4.2 years of follow-up, and postoperative subluxation occurred in the anterior direction in the upper cervical spine. X-ray evaluations revealed that such patients had a significantly smaller postoperative C2-C7 angle, and that the postoperative AA angle correlated negatively with this. Furthermore, anterior subluxation aggravation was significantly correlated with the perioperative atlantoaxial and C2-C7 angle changes, and these two changes were strongly correlated to each other. In conclusion, after atlantoaxial transarticular screw fixation, rheumatoid patients have a greater risk of developing subaxial subluxations. The increase of the atlantoaxial angel at the operation can lead to a decrease in the C2-C7 angle, followed by anterior subluxation of the upper cervical spine and possibly neurological deterioration.

show abstract

Section: Discussionmentioning

confidence: 99%

“…In cases when we used an atlas claw to fix the C1-C2 arches, only bone chips were grafted. The detail of the overall surgical techniques has been described elsewhere [17,19].…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Subaxial subluxation after atlantoaxial transarticular screw fixation in rheumatoid patients

et al. 2009

Self Cite

View full text Add to dashboard Cite

show abstract

“…The screw trajectory was directed as dorsally as possible (Fig. 2) to minimize the possibility of violating the anteriorly located C2 vertebral artery groove [15,17,18].…”

Section: Screw Trajectoriesmentioning

confidence: 99%

“…Two anatomic variations have been suggested to be associated with vertebral artery injury. First, it is well known that the risk of vertebral artery injury during C1-C2 transarticular screw placement increases with a high-riding vertebral artery [2,5,6,15,16]. However, we are unaware of any reports comparing the risk of vertebral artery injury by C1-C2 transarticular screw versus C2 pedicle screw in those with a high-riding vertebral artery, and no references on the topic could be found in a computerized search using MEDLINE.…”

Section: Introductionmentioning

confidence: 99%

Risk of vertebral artery injury: comparison between C1–C2 transarticular and C2 pedicle screws

et al. 2013

View full text Add to dashboard Cite

BACKGROUND CONTEXT: To our knowledge, no large series comparing the risk of vertebral artery injury by C1-C2 transarticular screw versus C2 pedicle screw have been published. In addition, no comparative studies have been performed on those with a high-riding vertebral artery and/ or a narrow pedicle who are thought to be at higher risk than those with normal anatomy. PURPOSE: To compare the risk of vertebral artery injury by C1-C2 transarticular screw versus C2 pedicle screw in an overall patient population and subsets of patients with a high-riding vertebral artery and a narrow pedicle using computed tomography (CT) scan images and threedimensional (3D) screw trajectory software. STUDY DESIGN: Radiographic analysis using CT scans. PATIENT SAMPLE: Computed tomography scans of 269 consecutive patients, for a total of 538 potential screw insertion sites for each type of screw. OUTCOME MEASURES: Cortical perforation into the vertebral artery groove of C2 by a screw. METHODS:We simulated the placement of 4.0 mm transarticular and pedicle screws using 1-mm-sliced CT scans and 3D screw trajectory software. We then compared the frequency of C2 vertebral artery groove violation by the two different fixation methods. This was done in the overall patient population, in the subset of those with a high-riding vertebral artery (defined as an isthmus height #5 mm or internal height #2 mm on sagittal images) and with a narrow pedicle (defined as a pedicle width #4 mm on axial images). RESULTS: There were 78 high-riding vertebral arteries (14.5%) and 51 narrow pedicles (9.5%). Most (82%) of the narrow pedicles had a concurrent high-riding vertebral artery, whereas only 54% of the high-riding vertebral arteries had a concurrent narrow pedicle. Overall, 9.5% of transarticular and 8.0% of pedicle screws violated the C2 vertebral artery groove without a significant difference between the two types of screws (p5.17). Among those with a high-riding vertebral artery, vertebral artery groove violation was significantly lower (p5.02) with pedicle (49%) than with transarticular (63%) screws. Among those with a narrow pedicle, vertebral artery groove violation was high in both groups (71% with transarticular and 76% with pedicle screws) but without a significant difference between the two groups (p5.55). CONCLUSIONS: Overall, neither technique has more inherent anatomic risk of vertebral artery injury. However, in the presence of a high-riding vertebral artery, placement of a pedicle screw is significantly safer than the placement of a transarticular screw. Narrow pedicles, which might be anticipated to lead to higher risk for a pedicle screw than a transarticular screw, did not result in a significant difference because most patients (82%) with narrow pedicles had a concurrent highriding vertebral artery that also increased the risk with a transarticular screw. Except in case of a high-riding vertebral artery, our results suggest that the surgeon can opt for either technique and expect similar anatomic risks of vertebral artery i...

show abstract

Vertebral Artery

George¹,

Bruneau²

2016

Bergman's Comprehensive Encyclopedia of Human Anatomic Variation

View full text Add to dashboard Cite

Atlantoaxial Transarticular Screw Fixation for a High-Riding Vertebral Artery

Abstract: It is possible to insert a screw safely, even into the narrow isthmus with a high-riding vertebral artery, if the surgeon realizes where the screw should be inserted and has the requisite insertion technique. Bilateral screw fixation should provide a high fusion rate.

Cited by 101 publications

References 25 publications

Subaxial subluxation after atlantoaxial transarticular screw fixation in rheumatoid patients

Subaxial subluxation after atlantoaxial transarticular screw fixation in rheumatoid patients

Risk of vertebral artery injury: comparison between C1–C2 transarticular and C2 pedicle screws

Vertebral Artery

Contact Info

Product

Resources

About