Applied anatomy of screw placement via the posterior arch of the atlas and anatomy-based refinements of the technique

Bodon, Gergely; Grimm, András; Hirt, Bernhard; Seifarth, Harald; Barša, Pavel

doi:10.1007/s00590-016-1771-1

Cited by 19 publications

(11 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using fluoroscopy for guidance is feasible and can show the safe direction of screws, especially in patients with posterior arch <4 mm. Complete or incomplete ponticulus posticus and a retrotransverse foramen or groove can be utilized as an accessory marker to clarify the entry point before screw placement [ 25 ]. In this study, a transverse foramen was taken as a landmark to protect the vertebral artery and refine the screw entry point by nail technique ( Figure 3 ).…”

Section: Discussionmentioning

confidence: 99%

Treatment of Upper Cervical Spinal Cord Injury (Unstable C1-C2) by Direct Visualization and Nailing Technique and the Advantages of Early MRI

Alshorman

Zeng

Wang

et al. 2021

Journal of Healthcare Engineering

View full text Add to dashboard Cite

Background. The treatment of C1-C2 fractures mainly depends on fracture type and the stability of the atlantoaxial joint. Disruption of the C1-C2 combination is a big challenge, especially in avoiding vertebral artery, nerve, and vein sinus injury during the operation. Purpose. This study aims to show the benefit of using the posterior approach and pedicle screw insertion by nailing technique and direct visualization to treat unstable C1-C2 and, moreover, to determine the advantages of performing early MRI in patients with limited neck movement after trauma. Method. Between Jan 2017–Feb 2019, we present 21 trauma patients who suffered from C1, C2, or unstable atlantoaxial joint. X-ray, computed tomography (CT), and magnetic resonance image (MRI) were performed preoperatively. All the patients underwent our surgical procedure (posterior approach and pedicle screw placement by direct visualization and nailing technique). Result. The mean age was 41.1 years old, 8 females and 14 males. The average follow-up time was 2.6 years. Four patients were with C1 fracture, seven with C2 fracture, six with atlantoaxial dislocation, and four with C1 and C2 fractures. The time of MRI was between 12 hours and 48 hours; neck movement symptoms appeared between 2 days and 2 weeks. Conclusion. The posterior approach to treat the C1 and C2 fractures or dislocation by direct visualization and nailing technique can reduce the risk of the vertebral artery, vein sinus, and nerve root injuries with significant improvement. It can show a better angle view while inserting the pedicle screws. An early MRI (12–48 hours) is essential even if no symptoms appear at the time of admission, and if it is normal, it is necessary to repeat it. The presence of skull bleeding can be associated with upper neck instability.

show abstract

Section: Discussionmentioning

confidence: 99%

Treatment of Upper Cervical Spinal Cord Injury (Unstable C1-C2) by Direct Visualization and Nailing Technique and the Advantages of Early MRI

Alshorman

Zeng

Wang

et al. 2021

Journal of Healthcare Engineering

View full text Add to dashboard Cite

show abstract

“…The RTF contains the anastomotic vein connecting the venous sinuses above the posterior arch of the atlas (the sub‐occipital cavernous sinus) and below it (vertebral and the vertebral artery venous plexus) (Bodon et al . 2016), and its prevalence in H. sapiens is approximately 7.5% (Sanchis‐Gimeno et al . 2018a).…”

Section: Discussionmentioning

confidence: 99%

Krapina atlases suggest a high prevalence of anatomical variations in the first cervical vertebra of Neanderthals

et al. 2020

View full text Add to dashboard Cite

The first cervical vertebra, atlas, and its anatomical variants have been widely studied in Homo sapiens. However, in Neanderthals, the presence of anatomical variants of the atlas has been very little studied until very recently. Only the Neanderthal group from the El Sidrón site (Spain) has been analysed with regard to the anatomical variants of the atlas. A high prevalence of anatomical variants has been described in this sample, which points to low genetic diversity in this Neanderthal group. Even so, the high prevalence of anatomical variations detected in El Sidrón Neanderthal atlases needs to be confirmed by analysing more Neanderthal remains. In this context, we analysed the possible presence of anatomical variants in the three Neanderthal atlases recovered from the Krapina site (Croatia) within the Neanderthal lineage. Two of the three Krapina atlases presented anatomical variations. One atlas (Krapina 98) had an unclosed transverse foramen and the other (Krapina 99) presented a non‐fused anterior atlas arch. Moreover, an extended review of the bibliography also showed these anatomical variations in other Middle and Upper Pleistocene hominins, leading us to hypothesise that anatomical variations of the atlas had a higher prevalence in extinct hominins than in modern humans.

show abstract

“…Gergely et al . 39 proved that height of penetration point of the pedicle screw was 4.70 mm in males, and 3.91 in females, respectively. Height of penetration point under 4 mm was 19.2% in males and 65% in females.…”

Section: Discussionmentioning

confidence: 87%

“…However, the C 1 pedicle screw method still faces some disadvantages, including the filmy external bone of the C 1 , back wise arches in a manner that the screw or drill could sideslip when operating, resulting in injury to the vertebral artery. Gergely et al 39 proved that height of penetration point of the pedicle screw was 4.70 mm in males, and 3.91 in females, respectively. Height of penetration point under 4 mm was 19.2% in males and 65% in females.…”

Section: Disadvantages Of the C 1 Pedicle Screw Methods And The Focus Of The Current Studymentioning

confidence: 98%

Biomechanical Effects of Lateral Inclination C₁ and C₂ Pedicle Screws on Atlantoaxial Fixation

Zhang

Wang

2021

Orthopaedic Surgery

View full text Add to dashboard Cite

Objective: To assess the biomechanical effect of lateral inclination C 1 and C 2 pedicle screws on the atlantoaxial fixation through vitro human cadaveric study. Methods:From January 2016 to December 2017, fresh-frozen cadaveric cervical spines with intact ligaments from eight donated cadavers at an average age of 71.5 AE 10.6 years, comprising of six males and two females, were collected. There were no fracture and congenital malformation in all specimens according to the imaging examination. The range of motion (ROM) of the specimens were tested in their intact condition and destabilized condition. Next, the specimens were randomly divided into two groups to ensure no differences in sex and age: Group 1 was medial inclination C 1 pedicle screw and C 2 pedicle screws (C 1 MPS-C 2 PS) and Group 2 was lateral inclination C 1 pedicle screw and C 2 pedicle screws (C 1 LPS-C 2 PS). The ROM of the fixation scenarios were recorded. Thereafter, all the specimens with fixation constructs were tested for 1,000 cycles of axial rotation and tensile loading to failure was carried out collinearly to the longitudinal axis of all the screws, the data were documented as screw pullout strength (SPS) in newtons. All the recorded data subjected to quantitative analysis. Results:The ROM of specimens was increased significantly in destabilized condition and significantly reduced in fixation condition compared with intact condition. In C 1 LPS-C 2 PS groups, the C 1 -C 2 cervical segment showed 3.96 AE1.21 and 3.75 AE 1.33 in flexion and extension direction, 2.85 AE 0.91 and 2.96 AE 0.71 in right and left lateral bending, 2.20 AE 0.43 and 2.15 AE 0.40 in right and left axial rotation. In C 1 MPS-C 2 PS groups, it showed 4.24 AE1.31 and 3.98 AE 1.21 in flexion and extension direction, 2.76 AE 1.10 and 3.23 AE 0.62 in right and left lateral bending, 2.20 AE 0.46 and 2.21 AE 0.42 in right and left axial rotation. There was no statistically significant difference on ROM and screw pullout strengths (764.29 AE 129.00 N vs 714.55 AE 164.63 N) between the two groups. However, there was one specimen in the C 1 MPS-C 2 PS group showing rupture the inferior wall of the left screw trajectory owing to the relatively thin posterior arch of the atlas, the screw pullout strength was significantly reduced (left pullout strength value: 430.5 N, right pullout strength value: 748.4 N). Therefore, in the case of the thin posterior arch of the atlas, the C 1 LPS-C 2 PS group had strong long-term biomechanics. Conclusion:The lateral inclination C 1 pedicle screw can achieve the same biomechanical strength as the traditional atlas pedicle screw. However, for the case where the posterior arch of the atlas is relatively thin, a lateral inclination C 1 pedicle screw is more suitable.

show abstract

Applied anatomy of screw placement via the posterior arch of the atlas and anatomy-based refinements of the technique

Cited by 19 publications

References 32 publications

Treatment of Upper Cervical Spinal Cord Injury (Unstable C1-C2) by Direct Visualization and Nailing Technique and the Advantages of Early MRI

Treatment of Upper Cervical Spinal Cord Injury (Unstable C1-C2) by Direct Visualization and Nailing Technique and the Advantages of Early MRI

Krapina atlases suggest a high prevalence of anatomical variations in the first cervical vertebra of Neanderthals

Biomechanical Effects of Lateral Inclination C₁ and C₂ Pedicle Screws on Atlantoaxial Fixation

Contact Info

Product

Resources

About

Applied anatomy of screw placement via the posterior arch of the atlas and anatomy-based refinements of the technique

Cited by 19 publications

References 32 publications

Treatment of Upper Cervical Spinal Cord Injury (Unstable C1-C2) by Direct Visualization and Nailing Technique and the Advantages of Early MRI

Treatment of Upper Cervical Spinal Cord Injury (Unstable C1-C2) by Direct Visualization and Nailing Technique and the Advantages of Early MRI

Krapina atlases suggest a high prevalence of anatomical variations in the first cervical vertebra of Neanderthals

Biomechanical Effects of Lateral Inclination C1 and C2 Pedicle Screws on Atlantoaxial Fixation

Contact Info

Product

Resources

About

Biomechanical Effects of Lateral Inclination C₁ and C₂ Pedicle Screws on Atlantoaxial Fixation