Management of Combined Atlas Fracture with Type II Odontoid Fracture: A Review of 21 Cases

The Establishment of a Novel Upper Cervical Complex Fracture Classification System

BACKGROUND CONTEXT

Upper cervical complex fractures are associated with high rates of neurological damage and mortality. The Dickman's classification is widely used in the diagnosis of upper cervical complex fractures. However, it falls short of covering the full spectrum of complex fractures. This limitation hinders effective diagnosis and treatment of these injuries.

PURPOSE

To address the diagnostic gap in upper cervical complex fractures, the study introduces a novel classification system for these injuries, assessing its reliability and usability.

STUDY DESIGN

Proposal of a new classification system for upper cervical complex fractures.

PATIENT SAMPLE

The study comprised the clinical data of 242 patients with upper cervical complex fractures, including 32 patients treated at our hospital, along with an additional 210 cases from the literature.

OUTCOME MEASURES

The inter-observer and intra-observer reliability (kappa coefficient, κ) of this classification system were investigated by 3 spine surgeons. The three researchers independently re-evaluated the upper cervical complex fracture classification system 3 months later.

METHODS

The proposed classification categorizes upper cervical complex fractures into three main types: Type I combines odontoid and Hangman's fractures into two subtypes; Type II merges C1 with odontoid/Hangman's fractures into three subtypes; and Type III encompasses a combination of C1, odontoid, and Hangman's fractures, divided into two subtypes. Meanwhile, a questionnaire was administered in 15 assessors to evaluate the system's ease of use and clinical applicability.

RESULTS

A total of 45 cases (18.6%) unclassifiable by Dickman's classification were successfully categorized using our system. The mean κ value of inter-observer reliability was 0.783, indicating substantial reliability. The mean κ value of intra-observer reliability was 0.862, indicating almost perfect reliability. Meanwhile, thirteen assessors (87.7%) stated that the classification system is easy to remember, easy to apply, and they expressed intentions to apply it in clinical practice in the future.

CONCLUSIONS

This system not only offers high confidence and reproducibility but also serves as a precise guide for clinicians in formulating treatment plans. Future prospective applications are warranted to further evaluate this classification system.

The Halofixator for the Treatment of Unstable Fractures of the Upper Cervical Spine - Our Own Experience and Narrative Review

INTRODUCTION

In the treatment of upper cervical spine injuries, the semiconservative procedure of the halofixator is now of only secondary importance. Older studies from the 2000 s showed unsatisfactory rates of consolidation as well as high rates of complications. However, due to current data on therapy effectiveness, the literature is inconsistent. The aim of this work is to compare our own experiences and results of treatment with the current literature and to help to clarify the role of the halofixator.

MATERIAL AND METHODS

In a monocentric retrospective cohort study, patients with unstable injuries of the axial cervical spine who were to be treated in the halofixator were investigated. Individual variables (sex, age, concomitant diseases, Charlson Comorbidity Index) and treatment characteristics (duration of treatment, consolidation status, complications) were recorded using the electronic medical record. Injuries were classified based on CT data at the time of the accident and at the end of treatment, using common classification systems, and assessed with respect to the rate of consolidation. Possible factors influencing bony consolidation as well as complications were statistically analysed.

RESULTS

A total of 54 patients met the inclusion criteria. The median duration of treatment was 83 days. The most common injuries were isolated atlas fracture type III (7; 13%) and isolated dens fracture type III (24; 44%). Bony consolidation was demonstrated in 34 cases (63%) and tight pseudarthrosis in 13 cases (24%). Secondary surgical stabilisation was performed in 6 cases (11%). Isolated type III atlas fractures and type III dens fractures had very high consolidation rates of 86% and 92%, respectively. In the subgroups of patients older than 65 years or with a CCI ≥ 4, unstable pseudarthroses were found more frequently. Complications included pin infection (6%), pin dislocation (9%), and pressure ulceration from the halo vest (6%). Cardiopulmonary complications did not occur. No patient died.

DISCUSSION

Good rates of bony consolidation were seen for atlas fractures type III as well as dens fractures type III, which correlate with data in the literature. Dens fractures type II (isolated and combined) and atlas fractures type III in combination with dens fractures showed a worse radiological outcome, which is also unsatisfactory compared to the literature. The rates for procedure-specific complications were relatively low. In particular, work from recent years has demonstrated very good rates for bony consolidation and low complication rates for the treatment of atlas and/or dens fractures with the halofixator, which are confirmed by our results. In contrast, however, a significantly higher cardiac/respiratory complication rate has been reported than occurred in our own patient population.

Atlas fractures with and without simultaneous dens fractures differ with respect to clinical, demographic, and management characteristics

Background

Patients with simultaneous fractures of the atlas and dens have traditionally been managed according to the dens fracture's morphology, but data supporting this practice are limited.

Methods

We retrospectively examined all patients with traumatic atlas fractures at our institution between 2008 and 2016. We used multivariable regression and propensity score matching to compare the presentation, management, and outcomes of patients with isolated atlas fractures to patients with simultaneous atlas-dens fractures.

Results

Ninety-nine patients were identified. Patients with isolated atlas fractures were younger (61 ± 22 vs. 77 ± 14, P = 0.0003), had lower median Charlson Comorbidity Index (3 vs. 5, P = 0.0005), had better presenting Nurick myelopathy scores (0 vs. 3, P < 0.0001), and had different mechanisms of injury (P = 0.0011). Multivariable regression showed that having a simultaneous atlas-dens fracture was independently associated with older age (odds ratio [OR] =1.59 [1.22, 2.07], P = 0.001), worse presenting myelopathy (OR = 3.10 [2.04, 4.16], P < 0.001), and selection for surgery (OR = 4.91 [1.10, 21.97], P = 0.037). Propensity score matching yielded balanced populations (Rubin's B = 23.3, Rubin's R = 1.96) and showed that the risk of atlas fracture nonunion was no different among isolated atlas fractures compared to simultaneous atlas-dens fractures (P = 0.304). Age was the only variable independently associated with atlas fracture nonunion (OR = 2.39 [1.15, 5.00], P = 0.020), having a simultaneous atlas-dens fracture was not significant (P = 0.2829).

Conclusions

Among patients with atlas fractures, simultaneous fractures of the dens occur in older patients and confer an increased risk of myelopathy and requiring surgical stabilization. Controlling for confounders, the risk of atlas fracture nonunion is equivalent for isolated atlas fractures versus simultaneous atlas-dens fractures.

Management of combined atlas and axis fractures: a systematic review

Background

Combined atlas-axis fractures are rare occurrences with substantially higher rates of neurologic deficits compared with isolated injuries. Given the intricate anatomic relationship between the atlas and axis vertebra, variable fracture patterns may occur, warranting special considerations from surgeons.

Methods

A systematic search of PubMed and EMBASE was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Relevant studies on acute combined atlas-axis fractures that provided data on patient demographics, presentation (injury mechanism, neurologic deficits, fracture type), management, complications, and study conclusions were reviewed.

Results

A total of 22 articles published from 1977 to 2022, comprising 230 patients, were included in the final analysis. Thirty-seven of the 213 patients (17%) presented with neurologic deficits. The most common atlas injuries were posterior arch fractures (54/169 patients; 32%), combined posterior arch/anterior arch fractures (44/169 patients; 26%), and anterior arch fractures (43/169 patients; 25%). The most common axis injuries were type II odontoid fractures (115/175 patients; 66%). Of the 127 patients managed operatively (127/230 patients; 55%), 45 patients (35%) were treated with C1-C2 posterior spinal fusion, 33 patients (26%) were treated with odontoid screw fixation and anterior/posterior C1-C2 trans-articular screws, 16 patients (13%) were treated with occiputocervical fusion and 12 patients (9%) were treated with odontoid screw fixation alone.

Conclusions

Management strategies are generally based on the type of axis fracture as well as the condition of the transverse ligament. Patients with stable fractures can be successfully managed nonoperatively with a cervical collar or halo immobilization. Combined atlas-axis fractures with an atlantodental interval >5 mm, C1 lateral mass displacement >7 mm, C2-C3 angulation >11° or an MRI demonstrating a disrupted transverse ligament are suggestive of instability and are often successfully managed with surgical intervention. There is no consensus regarding surgical technique.

Anterior reduction and C1-ring osteosynthesis with Jefferson-fracture reduction plate (JeRP) via transoral approach for unstable atlas fractures

Background

To introduce a novel transoral instrumentation in the treatment of unstable fractures of the atlas.

Methods

From January 2008 to May 2018, 22 patients with unstable C1 fractures who received Jefferson-fracture reduction plate (JeRP) via transoral approach were retrospectively analyzed. The case history and the radiographs before and after surgery were noted. The type of fracture, the reduction of the fracture, and position of the internal fixation were assessed through preoperative and postoperative CT scans.

Results

All 22 patients successfully underwent anterior C1-ring osteosynthesis using the JeRP system, with a follow-up of 26.84 ± 9.23 months. Among them, 9 patients had transverse atlantal ligament (TAL) injury, including 3 in Dickman type I and 6 in type II. The preoperative lateral mass displacement (LMD) decreased from 7.13 ± 1.46 mm to 1.02 ± 0.65 mm after the operation. Bone union was achieved in all patients without implant failure or loss of reduction. There were no surgery-related complications, such as wound infection, neurological deficit, or vertebral artery injury. However, atlantoaxial dislocation occurred in 3 patients with Dickman type I TAL injury 3 months postoperatively without any neurological symptoms or neck pain.

Conclusions

Transoral C1-ring osteosynthesis with JeRP is an effective surgical strategy to treat unstable atlas fractures with a safe, direct, and satisfactory reduction. The primary indication for the JeRP system is an unstable fracture (Gehweiler type I/III) or/ and TAL injury (Dickman type II).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04628-4.

C1 and C2 Fractures Above a Previous Fusion Treated with Internal Fixation without Fusion: A Case Report

CASE

A 71-year-old woman sustained C1 lateral mass and type 2 odontoid fractures 3 years after C2-T2 anterior-posterior fusion. She was treated with C1-C4 instrumentation without fusion for 9 months followed by instrumentation removal to restore atlantoaxial motion. After instrumentation removal, she maintained clinically relevant cervical lateral bending, rotation, and flexion and extension.

CONCLUSION

The loss of upper cervical motion after C1-C2 instrumented fusion may be debilitating for patients in the setting of previous subaxial cervical fusion. Temporary instrumentation without fusion may allow for preservation of upper cervical motion in patients with concomitant C1 and C2 fractures above a previous cervical fusion.