Traumatic Atlantoaxial and Fracture-Related Dislocation

The Rocker Technique for Atlantoaxial Dislocation With or Without Basilar Invagination: A Prospective Observational Study

BACKGROUND AND OBJECTIVES

Atlantoaxial dislocation (AAD) poses a complex surgical challenge. Surgical approaches vary for reducible and irreducible cases. Challenges persist in reducing the atlantodental interval, especially in cases with oblique or vertical C1-C2 joints. The Rocker instrument (MJ Surgical), a less-explored technique, seeks to simplify instrumentation, reduce complexity, and enhance translation and retroflection reduction of AAD.

METHODS

This prospective observational study was conducted from January 2022 to July 2023 at a tertiary neurosurgical center. Inclusion criteria covered all age groups with AAD, with or without basilar invagination. Exclusions included medically unstable patients and severe osteoporotic spine conditions. Preoperative assessments included dynamic X-rays, magnetic resonance imaging, and computed tomography scans. The Rocker technique was used, and patients were followed up for 6 to 12 months.

RESULTS

Fifty-five patients (30 males, 25 females) underwent surgery. The mean age was 40.41 ± 15.01 years. Successful Rocker technique application was observed in 53 cases. Functional outcomes, assessed using Modified Ranawat grading, showed improvement postoperatively. Radiological outcomes revealed a significant reduction in the anterior atlantodental interval (7.21 ± 0.94 to 2.98 ± 0.78). Basilar invagination was reduced in all cases, whenever present. The technique exhibited versatility, applicability in various joint orientations, and cost-effectiveness.

CONCLUSION

The Rocker technique is a safe and effective alternative for managing both reducible and irreducible AADs, with or without basilar invagination. It simplifies the reduction process, offering advantages over established techniques. Further trials, especially in rotational deformities, are warranted for validation.

Successful recovery from cardiac arrest due to atlantoaxial subluxation in Down syndrome: a case report

INTRODUCTION

Down syndrome is the most common chromosomal abnormality associated with intellectual impairments. Unexpected deaths are common with this disease. There are certain difficulties in clarifying the cause of death because the manifestations may be quite diverse and involve many organ systems. Atlantoaxial subluxation is a dangerous complication of Down syndrome, as it may lead to cervical cord-medullary compression.

CASE PRESENTATION

Herein, we present a case of Down syndrome in a patient who completely recovered from cardiac arrest due to atlantoaxial subluxation. The neck was immobilized during post-cardiac arrest care, and the patient underwent surgery after 14 days. The patient could walk independently and was discharged 3 months later. At the last follow-up 5 years after surgery, the patient's general condition was good.

DISCUSSION

Physicians should be aware that atlantoaxial instability can cause cardiac arrest in patients with genetic syndromes.

The retropharyngeal reduction plate for atlantoaxial dislocation: a finite element analysis

Objective: To investigate the biomechanical properties of the retropharyngeal reduction plate by comparing the traditional posterior pedicle screw-rod fixation by finite element analysis. Methods: Two three-dimensional finite element digital models of the retropharyngeal reduction plate and posterior pedicle screw-rod fixation were constructed and validated based on the DICOM (Digital Imaging and Communications in Medicine) data from C1 to C4. The biomechanical finite element analysis values of two internal fixations were measured and calculated under different conditions, including flexion, extension, bending, and rotation. Results: In addition to the backward extension, there was no significant difference in the maximum von Mises stress between the retropharyngeal reduction plate and posterior pedicle screw fixation under other movement conditions. The retropharyngeal reduction plate has a more uniform distribution under different conditions, such as flexion, extension, bending, and rotation. The stress tolerance of the two internal fixations was basically consistent in flexion, extension, left bending, and right bending. Conclusion: The retropharyngeal reduction plate has a relatively good biomechanical stability without obvious stress concentration under different movement conditions. It shows potential as a fixation option for the treatment of atlantoaxial dislocation.

Traumatic Posterior Atlantoaxial Dislocation With an Associated Fracture: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVE

To investigate the clinical presentation, mechanism of injury, patients' characteristics, diagnosis, treatment, and prognosis of traumatic posterior atlantoaxial dislocation with fracture (TPAD).

BACKGROUND

TPAD is an extremely rare entity, with a limited number of cases reported in the literature. Although rare, a thorough understanding of the pathogenesis and management of such cases is required due to the high risk of spinal cord compression and the severity of neurological deficits. We conducted a systematic review of all cases of TPAD with fractures reported in the literature.

METHODS

This systematic review was conducted following the Preferred Reporting Items for Systematic reviews and Meta-analysis guidelines. Relevant literature was retrieved from the Pubmed database. All published English-written studies involving human subjects with relevant data regarding TPAD were included.

RESULTS

Two case series and 20 case reports published between 1924 and 2021 describing 28 patients with TPAD were included. The median age at presentation was 51.5 years, with male predominance (83%). The most common fracture pattern was Anderson and D'alonzo type II odontoid fracture (78%). Neurological exam at presentation was intact in 52% of patients. The primary diagnostic imaging was computed tomography employed in 96% of cases. The management consisted of 2 stages protocol, initially, a temporary axial traction was employed (54%), and later definitive surgical treatment was employed (93%). The posterior surgical approach was favored in 82% of cases.

CONCLUSION

TPAD with fracture occurred in the majority of cases with Anderson and D'alonzo type II odontoid fracture, predominantly in males. Diagnosis is usually established based on computed tomography imaging; further imaging may not be indicated as it does not seem to alternate the patient's management course. Surgical intervention was employed in almost all cases, with favored results through posterior C1-C2 fusion.

LEVEL OF EVIDENCE

Level-IV.

Combined Odontoid (C2) and Atlas (C1) Fractures in Geriatric Patients: A Systematic Review and Treatment Recommendation

STUDY DESIGN

Systematic review.

OBJECTIVE

The aim of this study was to conduct a systematic overview of the pathogenesis and the treatment options of combined odontoid and atlas fractures in geriatric patients.

METHODS

This review is based on articles retrieved by a systematic search in the PubMed and Web of Science databases for articles published until February 2021 dealing with combination fractures of C1 and C2 in geriatric patients.

RESULTS

Altogether, 438 articles were retrieved from the literature search. A total of 430 articles were excluded. The remaining eight original articles were included in this systematic review depicting the topics pathogenesis, non-operative treatment, posterior approach, and anterior approach. The overall level of evidence of the studies is low.

CONCLUSION

Combined odontoid and atlas fractures in the geriatric population are commonly caused by simple falls and seem to be associated with atlanto-odontoid osteoarthritis. Non-operative treatment with a cervical orthosis is a feasible treatment option in the majority of patients with stable C2 fractures. In case of surgery posterior C1 and C 2 stabilization and anterior triple or quadruple screw fixation are possible techniques. Some patients may also deserve an occipito-cervical fusion. A possible treatment algorithm is proposed.

Comparison of the clinical efficacy of unilateral and bilateral pedicle screw short-segment fixation and fusion in the treatment of atlantoaxial fracture-dislocation

BACKGROUND

Few studies have compared the clinical efficacy of unilateral and bilateral pedicle screw fixation and fusion in treating atlantoaxial fracture-dislocation.

OBJECTIVE

To compare the efficacy of unilateral and bilateral fixation and fusion for atlantoaxial fracture-dislocation and to explore the feasibility of the unilateral surgical procedure.

METHODS

Twenty-eight consecutive patients with atlantoaxial fracture-dislocation were included in the study from June 2013 to May 2018. They were divided into a unilateral fixation group and a bilateral fixation group (14 patients in each group with an average age of 43.6 ± 16.3 years and 51.8 ± 15.4 years, respectively). The unilateral group had a unilateral anatomical variation of the pedicle or vertebral artery, or traumatic pedicle destruction. All patients underwent atlantoaxial unilateral or bilateral pedicle screw fixation and fusion. Intraoperative blood loss and operation time were recorded. The visual analog scale (VAS) and Japanese Orthopedic Association (JOA) scoring systems were used to evaluate pre- and postoperative occipital-neck pain and neurological function. X-ray and computerized tomography (CT) were used to assess atlantoaxial stability, the implants' position, and bone graft fusion.

RESULTS

All patients were followed up for 39-71 months postoperatively. Intraoperatively, no spinal cord or vertebral artery injury was observed. At the last follow-up, occipital-neck pain and neurological function in the two groups were significantly improved (P< 0.05). The X-ray films and CT showed satisfactory atlantoaxial stability, implant position, and osseous fusion in all the patients at 6 months postoperatively.

CONCLUSION

Unilateral and bilateral pedicle screw fixation and fusion can restore atlantoaxial stability and improve occipital-neck pain and neurological function in patients with atlantoaxial fracture-dislocation. The unilateral surgical procedure can be a supplementary option for patients with unilateral abnormal atlantoaxial lesions.

Interrelationship Between Craniocervical Dissociation Spectrum Injuries and Atlantoaxial Instability on Trauma Cervical MRI Examinations

Background and purpose Craniocervical dissociation injuries encompass a spectrum of osteoligamentous injuries between the skull base and C1-C2 that may be treated via prolonged external immobilization versus occipital cervical fusion depending on the risk of persistent craniocervical instability. However, the presence of atlantoaxial instability (AAI) at C1-C2, as determined by transverse atlantal ligament (TAL) integrity with or without a C1 fracture, may guide the neurosurgical management of craniocervical dissociation spectrum injuries (CDSI) since it implies an overall greater degree of instability at the craniocervical junction (CCJ). Materials and methods Adult trauma patients who suffered a transverse atlantal ligament injury on cervical magnetic resonance imaging (MRI) were identified retrospectively. The cervical computed tomography (CT) and magnetic resonance imaging examinations for these patients were reviewed for additional traumatic findings. Demographic information, treatment, and outcome information were recorded. Results Twenty-nine trauma patients presented to the emergency department (ED) with an acute, midsubstance transverse atlantal ligament tear on cervical magnetic resonance imaging. Thirty-one percent of patients demonstrated a tear in at least one major craniocervical ligament (atlanto-occipital capsular ligaments, alar ligaments, and tectorial membrane {TM}) with 14% demonstrating a tear in two major craniocervical ligaments and no patients demonstrating a tear in all three major craniocervical ligaments. Minor craniocervical ligament injuries (anterior atlanto-occipital membrane complex {AAOMc} and posterior atlanto-occipital membrane complex {PAOMc}) were common and observed in 76% of patients. Conclusions Our study suggests that multiple major craniocervical junction ligamentous injuries on cervical magnetic resonance imaging are relatively uncommon in the setting of transverse atlantal ligament injury.

Cervical fusion for adult patients with atlantoaxial rotatory subluxation

BACKGROUND

Atlantoaxial rotatory subluxation (AARS) is a rare injury of the C1/C2 junction. It is often associated with trauma in adults. Treatment may depend on the duration of symptoms and clinical presentation, but there is no consensus regarding the ideal management of these injuries. Our objective is to ascertain the prevalence of neurological deficit, complications, and outcomes of patients diagnosed with AARS undergoing cervical fusion (CF) versus those treated without CF.

METHODS

The 2016-2019 National Inpatient Sample (NIS) was queried using International Classification of Diseases, 10th revision (ICD-10) for adult patients with C1/C2 subluxation. Patients undergoing CF were defined through ICD-10 procedure codes. Baseline health and acute illness severity was calculated using the 11-point modified frailty index (mFI-11). Presenting characteristics, treatment complications, and outcomes were evaluated of CF vs. non-CF patients.

RESULTS

Of 990 adult patients with AARS, 720 were treated without CF and 270 were treated with CF. CF patients were more often myelopathic. Patients that had undergone CF treatment were negatively associated with having had extensive trauma. Patients undergoing CF experienced significantly longer length of stay (LOS), increased healthcare resource utilization, and decreased inpatient mortality. Sepsis had a negative association with patients that underwent CF treatment while pneumonia had a positive association.

CONCLUSIONS

Adult patients undergoing CF for AARS demonstrated an increase in healthcare resource utilization but also a significant decrease in mortality. Extent of acute injury appears to have a strong influence on decision making for CF. Further study of decision making for treatment of this rare injury in adults is warranted.

LOCKED-IN SYNDROME AFTER TRAUMATIC ATLANTOAXIAL SUBLUXATION: A CASE REPORT

ABSTRACT Traumatic atlanto-axial subluxation is a rare and underdiagnosed condition due to its high rate – reported to be between 60 and 80% – of early mortality. Its diagnosis takes into account the trauma mechanism, precise analyses of the imaging tests and the clinical presentation of the patient. This article describes a rare presentation of atlanto-axial subluxation associated with craniocervical dislocation as a case of locked-in syndrome. Level of evidence V; Retrospective observational study – Case report.

Does alar ligament injury predict conservative treatment failure of atlantoaxial rotatory subluxation in adults: Case report and review of the literature

INTRODUCTION

The alar ligament is an important structure in restraining the rotational movement at the atlantoaxial joint. While bony fractures generally heal, rupture of ligaments may heal poorly in adults and often requires surgical stabilization. Atlantoaxial rotatory subluxation (AARS) is a rare injury in adults, and the prognostic importance of the presence of alar ligament injury with regard to the success of nonoperative management is unknown.

CASE PRESENTATION

A 28-year-old woman presented after a traumatic Type I AARS without evidence of osseous injury, but MRI demonstrated evidence of unilateral alar ligament disruption. Initial conservative management with closed reduction and maintenance in a rigid cervical collar proved unsuccessful, with worsening pain and failure to maintain reduction. She subsequently underwent open reduction and surgical fixation of C1-C2, resulting in resolution of her pain and maintenance of alignment.

DISCUSSION

Alar ligament rupture may be a negative prognostic indicator in the success of nonoperative management of type I atlantoaxial rotatory subluxation. Additional study is warranted to better assess whether the status of the alar ligament should be considered an important factor in the management algorithm of type I AARS.

Extended tulip cervical reduction screws to restore alignment in traumatic atlantoaxial dislocation after type 3 odontoid fracture: illustrative case

BACKGROUND

Traumatic atlantoaxial rotatory subluxation after type 3 odontoid fracture is an uncommon presentation that may require complex intraoperative reduction maneuvers and presents challenges to successful instrumentation and fusion.

OBSERVATIONS

The authors report a case of a 39-year-old female patient who sustained a type 3 odontoid fracture. She was neurologically intact and managed in a rigid collar. Four months later, she presented again after a second trauma with acute torticollis and type 2 atlantoaxial subluxation, again neurologically intact. Serial cervical traction was placed with minimal radiographic reduction. Ultimately, she underwent intraoperative reduction, instrumentation, and fusion. Freehand C1 lateral mass reduction screws were placed, then C2 translaminar screws, and finally lateral mass screws at C3 and C4. The C2–4 instrumentation was used as bilateral rod anchors to reduce the C1 lateral mass reduction screws engaged onto the subluxated atlantodental complex. As a final step, cortical allograft spacers were inserted at C1–2 under compression to facilitate long-term stability and fusion.

LESSONS

This is the first description of a technique using extended tulip cervical reduction screws to correct traction-irreducible atlantoaxial subluxation. This case is a demonstration of using intraoperative tools available for the spine surgeon managing complex cervical injuries requiring intraoperative reduction that is resistant to traction reduction.

Upper Cervical Trauma

Craniocervical injuries (CCJs) account for 10% to 30% of all cervical spine trauma. An increasing number of patients are surviving these injuries due to advancements in automobile technology, resuscitation techniques, and diagnostic modalities. The leading injury mechanisms are motor vehicle crashes, falls from height, and sports-related events. Current treatment with urgent rigid posterior fixation of the occiput to the cervical spine has resulted in a substantial reduction in management delays expedites treatment of CCJ injuries. Within CCJ injuries, there is a spectrum of instability, ranging from isolated nondisplaced occipital condyle fractures treated nonoperatively to highly unstable injuries with severely distracted craniocervical dissociation. Despite the evolution of understanding and improvement in the management of cases regarding catastrophic failure to diagnose, subsequent neurologic deterioration still occurs even in experienced trauma centers. The purpose of this article is to review the injuries that occur at the CCJ with the accompanying anatomy, presentation, imaging, classification, management, and outcomes.

Longitudinal atlantoaxial dislocation associated with type III odontoid fracture due to high-energy trauma. Case report and literature review

INTRODUCTION

Traumatic upper cervical spine injuries are frequently associated with high-energy trauma. The potential injuries to vital organs associated to a possible neurological damage marks the severity of this pathology. The neurological structures can be affected by a primary injury, spinal cord, cranial nerves and spinal nerves; or secondary to a vascular compromise, mainly the vertebral arteries. The dislocation of the atlantoaxial joint causes an unstable cervical spine that could be often associated with fracture of the Atlas and Axis. Evidently, these have a high morbimortality rate.

CASE PRESENTATION

A young woman who suffered a severe polytrauma secondary to a motor vehicle collision was diagnosed with a sagittal plane atlantoaxial joint dislocation associated with a type III odontoid fracture, despite an adequate initial polytrauma management, the neurological damage was too critical, ultimately the decease of the patient.

DISCUSSION

The atlantoaxial joint dislocation is a rare condition of the upper cervical spine and is usually secondary to a high-energy traumatism. The disruption of the atlantoaxial ligaments originates the considered most unstable cervical spine lesion and with the highest mortality. Attributable to the kinetic the bone fracture of the Atlas and Axis are commonly related, specially the odontoid process. Early immobilization followed by surgical decompression and stabilization is primordial. Typically, these injuries have an ominous prognosis, that is aggravated if added a polytrauma affecting adjacent neurological structures and other vital organs.

Management of post-traumatic craniovertebral junction dislocation: A PRISMA-compliant systematic review and meta-analysis of casereports

Although historically considered fatal, with the advent of improved pre-hospital care, traumatic dislocation of the craniovertebral junction (CVJ) has been increasing in prevalence in neurosurgical centers. As more survivors are reported each year, a timely review with meta-analysis of their management seems necessary. PRISMA checklist was followed step by step. PubMed and Web of Science databases were searched using words “craniovertebral junction dislocation” and their corresponding synonyms. Study eligibility criteria included research studies from 2015 onwards that delineated adult and pediatric patients with confirmed post-traumatic atlantooccipital dislocation (AOD) or atlantoaxial dislocation (AAD) who survived until proper treatment. Of 1475 initial records, 46 articles met eligibility criteria with a total of 141 patients with traumatic CVJ dislocation. Of the patients, 90 were male (63.8%). Mean age of the cohort was 33.3 years (range 1–99 years). Trauma that most often led to this injury was road traffic accident (70.9%) followed by falls (24.6%). The majority of authors support posterior instrumentation of C1-C2 (45.2%) especially by means of Goel-Harms method. At mean follow-up of 15.4 months (range 0.5–60 months), 27.2% of treated patients remained neurologically intact. Of initially symptomatic, 59% improved, 37% were stable, and 4% deteriorated. Instrumenting the occiput in cases of pure AAD was associated with lower chance of neurological improvement in chi-square test (p = 0.0013) as well as in multiple linear regression (β = − 0.3; p = 0.023). The Goel-Harms C1-C2 fusion is currently the most frequently employed treatment. Many survivors remain with no deficits or improve, rarely deteriorate. Involving the occiput in stabilization in cases of AAD without AOD might be related with worse neurological prognosis.

Cardiopulmonary arrest induced by atlantoaxial dislocation with subarachnoid hemorrhage: a case report and review of the literature

Introduction

Spinal cord injury (SCI) with atlantoaxial dislocation (AAD) is often fatal. We present the case of a resuscitated patient with AAD and traumatic subarachnoid hemorrhage (SAH) at the craniovertebral junction (CVJ).

Case presentation

We present the case of an 84-year-old man who suffered an observed cardiopulmonary arrest. Cardiopulmonary resuscitation was initiated and spontaneous circulation returned. In the emergency room, the patient's Glasgow Coma Scale was 3 (E1V1M1). No spontaneous respiration was noted. Neuroimaging revealed SAH at the CVJ. Contrast-enhanced computed tomography (CT) revealed a vessel running through the left C2/3 intervertebral foramen into the spinal canal. The ventral space of spinal cord revealed contrast enhancement. Angiography revealed extravasation from the spinal branch of the left vertebral artery, without venous filling. It did not appear to be a vascular malformation with an arteriovenous shunt, but rather a traumatic laceration of the artery. Plain CT and CT angiography suggested AAD. Magnetic resonance imaging revealed injury to the medulla oblongata and upper cervical spinal cord, with AAD and retrodental subligamentous hemorrhage. We embolized the branch of the left vertebral artery and performed a C1 laminectomy. The patient moved his extremities postoperatively.

Discussion

This was a case of injury to the medulla oblongata and upper cervical spinal cord due to AAD with SAH. This is the first report of resuscitated case of traumatic AAD with SAH in the CVJ. Traumatic AAD should be included in the differential diagnosis in case of SAH in CVJ, which may be misdiagnosed as intrinsic SAH.