Traumatic Injuries to the Atlas

ABSTRACT

The purpose of this article was to study the anatomy, biomechanics, radiological findings, classification, clinical features, and different treatment modalities of atlas fractures.

We reviewed the literature concerning atlas fractures. All articles presented retrospective studies, either case series or case reports. Some biomechanical studies were also included. We conducted a cadaveric dissection of the occipitoatlantoaxial complex to study the ligaments, the articular surfaces, and the relationships to the vertebral artery, C1 and C2 nerves. We also reviewed some of our own cases to compare their management with the available literature and try to establish some treatment guidelines.

The most important factors of atlas stability are the transverse ligament, together with an intact odontoid and anterior arch of C1. Injuries affecting these elements usually require aggressive treatment; a halo if not displaced or surgical fusion if significant displacement is present. Occipitocervical fusions are a major compromise to craniocervical mobility, and should only be restricted to cases where C1-2 fusion cannot accomplish satisfactory stabilization.

KEYWORDS

Atlas - atlantoaxial instability - cervical spine injury - Jefferson's fracture - spinal fusion - spinal trauma

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