The significance of prevertebral soft tissue swelling in extension teardrop fracture of the cervical spine

Anterior reduction and fusion for treatment of massive tear drop fracture of axis combining with inferior endplate serious traversed lesion: A retrospective study

BACKGROUND

Tear drop fracture of axis represents a very small percentage of injuries of the cervical spine, but there is controversy about the treatment method for tear drop fracture of axis, especially when a large avulsed fragment is significant displacement, which combined with the inferior endplate serious traversed lesion of axis.

OBJECTIVE

To evaluate the clinical outcome of anterior reduction, graft fusion of C2-3 and plate fixation in the management of massive tear drop fracture of axis combining with inferior endplate serious traversed lesion of axis.

METHODS

There were 7 patients with a massive tear drop fracture of axis combining with inferior endplate serious traversed lesion. The avulsed ratio of inferior endplate of axis was 46.8 ± 13.4%, the average angle of rotation of the avulsed fragment was 30.4 ± 11.7, and the average displacement was 7.7 ± 2.8 mm. The posterior displacement of axis body was observed with three patients. All patients underwent anterior reduction, graft fusion of C2-3 and plate fixation with high anterior cervical retropharyngeal approach. The follow-up ranges from 2 years to 5 years.

RESULTS

In all cases, tear drop fracture was reduced completely, avulsed fragment got bony healing, and bone graft achieved bony fusion at C2-3. There were no local angle deformity and rotated deformity in all patients, and there were normal physiological lordosis and good stabilization of upper cervical spine. The neurological function of one patient with American Spine Injury Association (ASIA) impairment scale type D was improved to type E postoperatively. Six patients without neurological lesion had no neurological syndrome after operation.

CONCLUSIONS

Anterior surgical procedures would be an effective treatment of massive tear drop fracture of axis combining with inferior endplate serious traversed lesion. Complete reduction, sufficient stabilization and normal physiological lordosis of upper cervical spine could be achieved postoperatively.

Conservative and Operative Treatment in Extension Teardrop Fractures of the Axis

STUDY DESIGN

A retrospective case series describing teardrop fracture of the axis.

OBJECT

The purpose of the study was to clarify the clinical features, the mechanism of injury, and the potential instability of extension teardrop fractures of the axis, so as to emphasize the importance of recognizing this injury as a separate entity.

SUMMARY OF BACKGROUND DATA

Teardrop fractures of the axis are rare spinal fractures, comprising only a small percentage of all injuries of the cervical spine. The stability of this fracture pattern has been a matter of debate leading to controversy regarding treatment strategies and the need for stabilization.

METHODS

We retrospectively reviewed data collected from 16 patients to document the mechanism of injury, neurological deficit, treatment and clinical outcome, and imaging findings.

RESULTS

Extension teardrop fractures accounted for approximately 8.9% of the upper cervical spinal injuries and 12.7% of axis fractures at the authors' institution over the same period. Six patients (4 males and 2 females) underwent surgery (4 by an anterior approach, 2 by a posterior approach). Ten cases underwent Halo-vest immobilization for a period between 6 and 12 weeks. At final follow-up, 14 cases achieved excellent results, whereas 2 patients complained of mild residual neck pain. Maximum cranial-caudal dimensions of the fragments were between 5 and 24 mm (average, 12.9 mm), and the transverse dimensions were between 5 and 22 mm (average, 11.1 mm). Fragment displacement ranged from 1 to 9 mm (average, 3.5 mm), whereas fragment rotation ranged from 10 to 52 degrees (average, 24.4 degrees) in the sagittal plane.

CONCLUSIONS

Most patients with an extension teardrop fracture of the axis can be treated conservatively. On the basis of this case series, the authors suggest that large fragment size, displacement or angulation, intervertebral disk injury, neurologic deficit, or signs of instability are reasonable indications for surgical treatment.

Clinical features of the extension teardrop fracture of the axis: review of 13 cases

Object

Extension teardrop fracture of the axis is an extremely rare cervical spinal injury. The classic clinical features, which have mainly been described by radiologists rather than spine surgeons, include its occurrence in elderly patients with osteoporosis, an association with minimal or no prevertebral soft-tissue swelling, and an absence of associated neurological deficit. However, recent case studies indicate notable exceptions to these clinical features, although few studies have investigated osteoporosis in these patients. The purpose of the present study was to clarify the clinical features of extension teardrop fracture of the axis.

Methods

The authors retrospectively reviewed data obtained in 13 patients with regard to their injury etiology, neurological deficit, treatment and outcome (residual neck pain), and imaging findings (size and displacement of the fragment, C2–3 subluxation, disc injury, and osteoporosis of the axis).

Results

Extension teardrop fracture of the axis constituted 11.6% of upper cervical spinal injuries at the authors' institute. The mean age of the patients was 49.5 years and distinct osteoporosis was identified in only 1 patient. A C2–3 subluxation was observed in 2 patients, in whom the displacement of the fragment was significant, although its size did not appear to have an effect. Magnetic resonance imaging, undertaken in 7 patients within 48 hours of injury, showed no disc injuries. Instability of the cervical spine was absent in all patient at follow-up. Only one patient underwent surgery for the presenting symptoms of dysphagia. The other patients were treated conservatively. The authors examined 9 patients directly; these patients had bony fusion and did not complain of neck pain, except for a patient with traumatic spondylolisthesis.

Conclusions

Extension teardrop fracture of the axis is generally caused by hyperextension of the cervical spine caused by a direct high-energy blow to the forehead or mandible. Based on the present case study, the authors believe that osteopenia and older age should not be considered risk factors. Most patients with an extension teardrop fracture of the axis can be treated conservatively, and surgical intervention may only be indicated for specific cases, such as those in which a patient presents with dysphagia or with other complicated fractures.

Spectrum of imaging findings in hyperextension injuries of the neck

Nonphysiologic hyperextension and lateral forces acting on the cervical spine and soft-tissue structures of the neck can result in a wide spectrum of injury patterns. Multiple factors (eg, patient age; the underlying morphologic features of the cervical spine; the magnitude, vector, and maximal focus of the force) all influence the observed patterns and the severity of injury. A review of the 5-year trauma database in two trauma centers revealed various injury patterns that were frequently recognized in patients with clinical evidence or historical documentation of a predominant hyperextension mechanism. Injuries included anterior arch avulsion and posterior arch compression fractures of the atlas, odontoid fractures, traumatic spondylolisthesis and teardrop fracture of C2, laminar and articular pillar fractures, and hyperextension dislocation injuries. More severe injuries were observed in patients with underlying predisposing conditions (eg, degenerative spondylosis, ankylosing spondylitis, diffuse idiopathic skeletal hyperostosis). Knowledge of the involved biomechanical factors provides a framework for understanding these injury patterns. Diagnostic imaging, especially computed tomography and magnetic resonance imaging, plays a fundamental role in the assessment of patients with suspected cervical injury. Furthermore, cross-sectional imaging facilitates the recognition of accompanying injuries to the face, the head, and the vascular structures of the neck.