How Does Cervical Sagittal Balance Change After Hangman Fracture Treated with Anterior or Posterior Approach Surgery?

Biomedical analysis of four fixation systems in treatment of type II traumatic spondylolisthesis of the axis: a finite element analysis

This study aimed to compare the properties and safety of self-designed plates in type II traumatic spondylolisthesis of the axis with those of traditional devices via finite element (FE) analysis. We constructed a hangman's fracture FE model from the occipital bone (C0) level to the C3 level. Then, FE models were constructed for the following four fixation systems: an anterior cervical L-shaped plate with four vertebral screws (4-ACLP), or six screws (6-ACLP), an anterior cervical orion plate (ACOP), and a posterior fixation system. A preloaded compressive force of 50 N and a moment of 1.5 N·m were applied to each model under six working conditions. The mobility of the C2/3 segment decreased significantly in four fixation models. In the Mises stress cloud diagram, 4-ACLP showed a better stress distribution in both the bone graft and fixation system than 6-ACLP and ACOP. The resultant force of 4-ACLP was lower but higher than ACOP in axial force. Additionally, the cage in the 4-ACLP configuration experienced the highest stress in the six working conditions. Hence, this novel self-designed plate has the potential to mitigate the operational difficulties, provide sufficient stability, reduce the risk of plate or screw fractures, and improve bone fusion.

Comparison of complication rates between anterior versus posterior approaches for treating unstable Hangman's fracture. A systematic review and meta-analysis

Study design

Systematic Review and Meta-analysis.

Objective

To compare the complication rates associated with anterior and posterior approaches for the surgical treatment of unstable hangman's fractures.

Methods

A systematic review and meta-analysis were performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in PubMed, Web of Science, and Scopus databases to identify comparative studies reporting complications of anterior versus posterior approaches for the treatment of unstable hangman's fractures.

Results

The search yielded 1163 papers from which 5 studies were fully included. One hundred fifteen (115) patients were operated on using an anterior approach versus 65 through a posterior approach. The average complication rates for the anterior and posterior approaches were 26.1 % and 13.8 %, respectively. No complications following the anterior approach required pharmacological or surgical intervention (Clavien-Dindo, Grade 1), while 88.9 % of complications following the posterior approach did (Clavien-Dindo, Grade 2).

Conclusion

No significant differences in the complication rates were found when comparing anterior versus posterior surgery for treating a C2 traumatic spondylolisthesis. However, most of the complications presented in the posterior surgery group were more severe.

Anterior C2-3 fusion surgery alone for highly displaced Hangman's fracture with severe angulation of C2-3 of more than 30°

BACKGROUND

Highly displaced Hangman's fracture is a very rare and extremely unstable fracture of the C2 axis. Combined anteroposterior or posterior long-segment fusion surgery is typically performed for the treatment of highly displaced Hangman's fracture. However, these kinds of surgeries increase the risk of complications, loss of motion, and hospital costs.

OBJECTIVE

We sought to investigate the surgical outcomes of anterior C2-3 fusion surgery alone for highly displaced Hangman's fractures with severe angulation of C2-3 by more than 30° and discoligamentous injury.

METHODS

A total of five patients (four men and one woman) were included in this study with a mean age of 40.4 years (range, 26-70 years). The mean follow-up period after surgery was 37.2 months (range, 12-96 months). The fracture characteristics, treatment methods, and outcomes were retrospectively analyzed.

RESULTS

All five patients had type II Hangman's fractures (according to the Levine and Edwards classification scheme). None of the included patients had neurologic deficit or other spine injury but all patients had complete C2-3 discoligamentous injury. Before surgery, all patients successfully achieved closed reduction by skull traction, followed by C2-3 anterior decompression and fusion (ACDF) with plating. For interbody grafting, three patients received a polyetheretherketone (PEEK) cage filled with an autogenous cancellous iliac bone graft and two received autogenous tricortical iliac bone grafts. Severe angulation (39.2° vs. 3.0°, P < 0.001) and severe displacement (76.1% vs. 4.0%, P < 0.001) of C2-3 were both significantly corrected after surgery. All patients had achieved solid fusion at last follow-up. In terms of clinical outcomes, the mean neck pain visual analog scale score was significantly improved (8.6 points vs. 1.8 points, P < 0.001). The mean neck disability index value was also significantly improved (45.4 points vs. 13.0 points, P < 0.01). According to Odom's criteria, all patients achieved satisfactory outcomes. No major complications occurred. One patient complained of dysphagia, but recovered after three months with conservative treatment.

CONCLUSIONS

Preoperative closed reduction and anterior C2-3 fusion surgery alone should be considered as a less-invasive and useful surgical option for highly displaced Hangman's fracture with severe angulation of C2-3, which is an extremely unstable fracture of the C2 axis.

The Effect of Anterior Cervical Discectomy and Fusion on Cervical Sagittal Vertical Axis and Lordosis with Minimum 2-Year Follow-Up

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) can induce lordosis and improve cervical sagittal vertical axis (SVA), but multilevel ACDF may inadvertently increase cervical SVA because of insufficient lordosis induction.

METHODS

Patients who underwent 1-, 2-, or ≥3-level ACDF in the subaxial spine with minimum 2-year follow up were retrospectively studied. C2-C7 Cobb angle (lordosis), cervical SVA, and T1 slope were measured preoperatively, immediately postoperatively, and at last follow-up.

RESULTS

Inclusion criteria were met by 127 patients. There were no differences in baseline demographics among 1-, 2-, and ≥3-level ACDF groups. Mean follow-up was 43.7 months (range, 24-142 months). Increase of cervical SVA immediately postoperatively was 1.94 mm, -1.44 mm, and 7.25 mm for 1-, 2-, and ≥3-level ACDF (P = 0.041) and at last follow-up was 2.97 mm, 0.70 mm, and 9.32 mm for 1-, 2-, and ≥3-level ACDF (P = 0.026). At last follow-up, 2-level ACDF patients had the greatest decrease in T1 slope (-0.43°) compared with increase of 2.71° for 1-level and 2.84° for ≥3-level patients (P = 0.028). In all 3 groups, segmental (ACDF levels) lordosis, cervical SVA, and T1 slope did not decrease from immediate postoperative to last follow-up. Only 2-level ACDF maintained C2-7 lordosis (2.16°) compared with loss of lordosis in 1-level (-0.84°) and ≥3-level (-2.00°) ACDF (P = 0.008) at last follow-up. Linear regression analysis showed that T1 slope had no relationship with correction of cervical SVA (P = 0.5310) but had a significant correlation with Cobb angle loss of C2-C7 lordosis (P = 0.0016).

CONCLUSIONS

Compared with 1- and 2-level ACDF, ≥3-level ACDF resulted in significant increase of cervical SVA and loss of overall lordosis. Compared with 1- and ≥3-level ACDF, 2-level ACDF had the greatest ability to maintain lordosis. T1 slope had a significant correlation with loss of C2-C7 lordosis after ACDF.

Unstable Hangman Fracture Complicated by Vertebral-Venous Fistula: Surgical Considerations and Review of Literature

BACKGROUND

Hangman fracture or traumatic spondylolisthesis of the axis associated with a traumatic vertebral venous fistula (VVF) is a rare entity and sparsely reported in literature. Standard recommendations for management of such rare and complex scenarios are not available and hence the strategy has to be individualized on a case-by-case basis.

METHODS

We report a 70-year-old man having an unstable hangman fracture with VVF. Both pathologies were simultaneously managed uniquely. The VVF was managed by endovascular occlusion. The fracture was managed by anterior fusion alone as posterior fusion was deemed riskier in the aftermath of a recently occluded VVF. The patient had good neck function and bony fusion at 1-year follow-up.

CONCLUSION

This case report emphasizes the need for timely recognition and management of a VVF, which can rarely coexist with hangman fracture, and discusses the interesting surgical paradigms in the management. We also present a review of literature.