Presentation
Axial load and fall forward from an impact with industrial machinery. Severe central neck pain with some mild radicular pain in the left C6 distribution.
Patient Data
Unstable fractures involving the left C5 superior facet left posterior arch of C6, left C6 superior facet, junction of the body and left pedicle of C6, which are associated with anterior spondylolisthesis of C6/7.
The atlantoaxial and atlantooccipital articulations are congruent. Normal cervical spine alignment is maintained. The bilateral facet joints are not dislocated. No displaced cervical spine fracture. No destructive osseous lesions.
Pre and post vertebral soft tissue planes are maintained. No cervical lymphadenopathy. The visualized trachea, esophagus and thyroid are unremarkable.
CT angiography was conducted, which did not identify any vertebral artery injury.
The posterior longitudinal ligament has been stripped off the C6 body associated with a minor posterolisthesis (2 mm) and small volume fluid. The ligament remains attached to the vertebral bodies above and below (inferior posterior corner of C5 and superior posterior C7). The anterior longitudinal ligament remains intact. No abnormal intradiscal signal.
Posteriorly, focal buckling can be seen along the ligamentum flavum between C6 and C7. Interspinous edema present between C2-C7. More posteriorly, soft-tissue edema is present between the spinous processes and the nuchal ligament, also in the adjacent paraspinal tissue posterior to C2-C6, and more ex inferiorly extensive down to T3 just to the left.
The comminuted fracture through the left C6 posteroinferior vertebral body, pedicle, lamina, pars, superior and inferior facet processes is also visible.
Widening of C6-C7 left facet joint in keeping with capsular injury. Subtle undulation in inferior articular process C5. Subtle marrow edema within the C2 spinous process.
The vertebral arteries are bilaterally smooth in contour, with no evidence of pseudoaneurysm/dissection. Unremarkable carotid arteries.
Case Discussion
The patient was managed conservatively with an immobilization collar for 6 weeks and progressed slowly afterwards. He made a full recovery and returned to work without any concerns.
Floating lateral mass fractures are not well studied in the literature, due to their variability of severity and relatively rare occurrence. Due to the involvement of two motion segments, they can be inherently unstable. Studies suggest the majority undergo surgical fixation with either anterior cervical decompression and fusion, or posterior pedicle screw fixation, based on displacement and operator preference.
In this instance, due to the patient's minimal fracture displacement, minor ligamentous injury with no vertebral artery injury, he could be treated conservatively.