Subaxial Sagittal Alignment After Atlantoaxial Fixation Techniques

The authors present a novel technique of atlantoaxial fixation using multiaxial C-1 posterior arch screws. The technique involves the insertion of bilateral multiaxial C-1 posterior arch screws, which are connected by crosslinked rods to bilateral multiaxial C-2 pars screws. The clinical results are presented in 3 patients in whom anomalies of the vertebral arteries, C-1 lateral masses, and/or posterior arch of C-1 presented difficulty using existing fixation techniques with transarticular screws, C-1 lateral mass screws, or posterior wiring. The C-1 posterior arch screws achieved solid fixation and their insertion appeared to be technically less demanding than that of transarticular or C-1 lateral mass screws. This technique may reduce the risk of complications compared with existing techniques, especially in patients with anatomical variants of the vertebral artery, C-1 lateral masses, or C-1 posterior arch. This technique may prove to be an attractive fixation option in patients with normal anatomy.

Download Full-text

Sagittal alignment correlates with the C1-C2 fixation angle and functional outcome after posterior atlantoaxial fixation for traumatic atlantoaxial instability

Journal of Clinical Neuroscience ◽

10.1016/j.jocn.2019.05.034 ◽

2019 ◽

Vol 66 ◽

pp. 19-25

Author(s):

Dae Han Choi ◽

Sang Gu Lee ◽

Chan Jong Yoo ◽

Woo Kyung Kim ◽

Seong Son

Keyword(s):

Functional Outcome ◽

Sagittal Alignment ◽

Atlantoaxial Instability ◽

Atlantoaxial Fixation ◽

C2 Fixation

Download Full-text

Biomechanical Testing of Posterior Atlantoaxial Fixation Techniques

Spine ◽

10.1097/00007632-200211150-00004 ◽

2002 ◽

Vol 27 (22) ◽

pp. 2435-2440 ◽

Cited By ~ 184

Author(s):

Robert P. Melcher ◽

Christian M. Puttlitz ◽

Frank S. Kleinstueck ◽

Jeffrey C. Lotz ◽

Juergen Harms ◽

...

Keyword(s):

Biomechanical Testing ◽

Fixation Techniques ◽

Atlantoaxial Fixation

Download Full-text

Subaxial sagittal alignment and adjacent-segment degeneration after atlantoaxial fixation performed using C-1 lateral mass and C-2 pedicle screws or transarticular screws

Journal of Neurosurgery Spine ◽

10.3171/2010.4.spine09662 ◽

2010 ◽

Vol 13 (4) ◽

pp. 443-450 ◽

Cited By ~ 33

Author(s):

Go Yoshida ◽

Mituhiro Kamiya ◽

Hisatake Yoshihara ◽

Tokumi Kanemura ◽

Fumihiko Kato ◽

...

Keyword(s):

Sagittal Alignment ◽

Screw Fixation ◽

Adjacent Segment ◽

Lateral Mass ◽

Transarticular Screw ◽

Transarticular Screw Fixation ◽

Significant Difference ◽

Atlantoaxial Fixation ◽

The Mean ◽

The Difference

Object The purpose of this study was to evaluate the effect of a fixed atlantoaxial angle on subaxial sagittal alignment, and that of atlantoaxial fixation on adjacent-segment motion and degeneration. Methods The authors retrospectively reviewed 65 patients in whom atlantoaxial instability was treated with atlantoaxial fixation by C-1 lateral mass and C-2 pedicle screw fixation (30 patients, Goel-Harms [GH] group) or a combination of transarticular screw fixation and posterior wiring (35 patients, Magerl-Brooks [MB] group). Angles of Oc–C1, C1–2, C2–3, and C2–7 were determined based on an upright lateral radiograph in flexion, neutral, and extension positions. The range of motion (ROM) at Oc–C1 and C2–3 was also determined. All patients were examined before and 2 years after surgery. Results The mean preoperative atlantoaxial angles in the GH and MB groups were 20.9 ± 8.3° and 18.3 ± 7.2°, respectively, and the mean postoperative atlantoaxial angles in the same groups were 23.5 ± 5.6° and 29.7 ± 6.3°, respectively, with a statistically significant difference between the 2 groups (p < 0.05). The mean preoperative angles of C2–7 in the GH and MB groups were 15.4 ± 7.8° and 13.7 ± 9.5°, respectively, and after surgery, the angles were 11.8 ± 12° and 2.48 ± 12°, respectively, with a statistically significant difference between the 2 groups (p < 0.05). The postoperative angle of C1–2 showed a negative correlation with the extent of change observed in the C2–7 angle preand postoperatively in each of these 2 surgical procedures. The Oc–C1 ROM increased after surgery in both groups, but the difference was not statistically significant (p = 0.38). The C2–3 ROM decreased after surgery in both groups, and the difference was statistically significant (p < 0.05). Conclusions Atlantoaxial fixation in a hyperlordotic position produced kyphotic sagittal alignment after surgery in both GH and MB groups. Reduction of the atlantoaxial joint can be easily achieved through screw fixation at an optimal angle, thereby ameliorating the risk for subsequent subaxial kyphosis. Degeneration of lower adjacent segments appeared to be less with this procedure compared with using a combination of transarticular screw fixation and posterior wiring.

Download Full-text

Biomechanical Evaluation of Four Different Posterior Atlantoaxial Fixation Techniques

Spine ◽

10.1097/00007632-199205000-00003 ◽

1992 ◽

Vol 17 (5) ◽

pp. 480-490 ◽

Cited By ~ 296

Author(s):

Dieter Grob ◽

Joseph J. Crisco ◽

Manohar M. Panjabi ◽

Ping Wang ◽

Jiri Dvorak

Keyword(s):

Fixation Techniques ◽

Atlantoaxial Fixation ◽

Biomechanical Evaluation

Download Full-text

Atlantoaxial Fixation Techniques

10.1007/978-981-10-7889-7 ◽

2018 ◽

Cited By ~ 2

Keyword(s):

Fixation Techniques ◽

Atlantoaxial Fixation

Download Full-text

C2 Translaminar Screw Fixation (Wright`s Technique) Applicability in Atlantoaxial Instability

JBNC - JORNAL BRASILEIRO DE NEUROCIRURGIA ◽

10.22290/jbnc.v23i2.1163 ◽

2018 ◽

Vol 23 (2) ◽

pp. 152-156

Author(s):

Lucas Alves Aurich ◽

Jerônimo Buzetti Milano ◽

Erasmo Barros Da Silva Júnior ◽

Ricardo Ramina

Keyword(s):

Screw Fixation ◽

Atlantoaxial Instability ◽

Rigid Fixation ◽

Fixation Technique ◽

Advantages And Disadvantages ◽

Risks And Benefits ◽

Translaminar Screw Fixation ◽

Translaminar Screw ◽

Fixation Techniques ◽

Atlantoaxial Fixation

Atlantoaxial instability often requires surgical treatment. Several techniques are available to perform antlantoaxial stabilization, and all of these have their different advantages and disadvantages. In 2004, Wright described the C2translaminar screw fixation, which offers rigid fixation but without the technical demands of C2 pars placement and eliminates the risk of vertebral artery injury. The aim of this study is to review the C2 translaminar screw fixation technique, emphasizing operative details, risks and benefits comparing with the others atlantoaxial fixation techniques.

Download Full-text

Structural aspects of tracheary element differentiation in suspension cultures of Zinnia elegans

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155815 ◽

1989 ◽

Vol 47 ◽

pp. 768-769

Author(s):

C. H. Haigler ◽

A. W. Roberts

Keyword(s):

Tracheary Element ◽

Vesicle Fusion ◽

Zinnia Elegans ◽

Cellulose Synthesis ◽

Tracheary Elements ◽

Animal Cells ◽

Mesophyll Cells ◽

Fixation Techniques ◽

Localized Patterns ◽

Structural Aspects

Tracheary elements, the water-conducting cells in plants, are characterized by their reinforced walls that became thickened in localized patterns during differentiation (Fig. 1). The synthesis of this localized wall involves abundant secretion of Golgi vesicles that export preformed matrix polysaccharides and putative proteins involved in cellulose synthesis. Since the cells are not growing, some kind of endocytotic process must also occur. Many researchers have commented on where exocytosis occurs in relation to the thickenings (for example, see), but they based their interpretations on chemical fixation techniques that are not likely to provide reliable information about rapid processes such as vesicle fusion. We have used rapid freezing to more accurately assess patterns of vesicle fusion in tracheary elements. We have also determined the localization of calcium, which is known to regulate vesicle fusion in plant and animal cells.Mesophyll cells were obtained from immature first leaves of Zinnia elegans var. Envy (Park Seed Co., Greenwood, S.C.) and cultured as described previously with the following exceptions: (a) concentration of benzylaminopurine in the culture medium was reduced to 0.2 mg/l and myoinositol was eliminated; and (b) 1.75ml cultures were incubated in 22 x 90mm shell vials with 112rpm rotary shaking. Cells that were actively involved in differentiation were harvested and frozen in solidifying Freon as described previously. Fractures occurred preferentially at the cell/planchet interface, which allowed us to find some excellently-preserved cells in the replicas. Other differentiating cells were incubated for 20-30 min in 10(μM CTC (Sigma), an antibiotic that fluoresces in the presence of membrane-sequestered calcium. They were observed in an Olympus BH-2 microscope equipped for epi-fluorescence (violet filter package and additional Zeiss KP560 barrier filter to block chlorophyll autofluorescence).

Download Full-text

Open reduction of pediatric lateral condyle fractures: a systematic review

Shoulder & Elbow ◽

10.1177/17585732211010299 ◽

2021 ◽

pp. 175857322110102

Author(s):

Michael D Eckhoff ◽

Josh C Tadlock ◽

Tyler C Nicholson ◽

Matthew E Wells ◽

EStephan J Garcia ◽

...

Keyword(s):

Systematic Review ◽

Internal Fixation ◽

Range Of Motion ◽

Lateral Condyle ◽

Elbow Fracture ◽

Infection Rates ◽

Fixation Techniques ◽

K Wires ◽

Pediatric Elbow Fracture ◽

The Cost

Introduction Lateral condyle fractures are the second most common pediatric elbow fracture. There exist multiple options for internal fixation including buried K-wires, unburied K-wires, and screw fixation. Our study aims to review the current literature and determine if fixation strategy affects outcomes to include fracture union, postoperative range of motion, and need subsequent surgery. Methods A systematic review of Pubmed, MEDLINE, and EMBASE databases was performed. Included articles involve pediatric patients with displaced lateral condyle fractures treated with internal fixation that reported outcomes to include union rates and complications. Results Thirteen studies met inclusion criteria for a total of 1299 patients (472 buried K-wires, 717 unburied K-wires, and 110 screws). The patients’ average age was 5.8 ± 0.6 years, male (64%), and had 16.3 months of follow-up. No differences in union and infection rates were found. Unburied K-wires had the shortest time to union and the greatest elbow range of motion postoperatively. Conclusions Our systematic review demonstrates similar outcomes with union and infection rates between all fixation techniques. Unburied K-wires demonstrated a shorter time to union and the greatest postoperative range of motion. Additionally, unburied K-wires may be removed in clinic, decreasing the cost on the healthcare system. Evidence Level 3.

Download Full-text