Traumatic spondylolisthesis of the axis – A South African surgical case series

Fractures of the axis are relatively common and account for 20–30% of cervical spine fractures overall. Bilateral fractures of the C2 pars interarticularis with traumatic spondylolisthesis, colloquially referred to by the misnomer “Hangman's fracture”, are noted now-days to be commonly incurred in the context of motor vehicle accidents. Post-mortem examination of hung individuals has demonstrated that only approximately 10% of victims have this fracture type. The Levine and Edwards classification is mechanistic, and categorizes these fractures into three basic types. A Type 1 fracture is a stable injury and can be managed as effectively by C2 pars screws, C2 pedicle screws, or external immobilization. Several papers note an almost 100% fusion rate with external immobilization and this is the most frequently recommended treatment for this fracture type. Type 2 fractures are similarly regarded as stable, however significant C2/C3 subluxation, or C2/C3 angulation, may result in these fractures being managed operatively, or if closed reduction can be achieved, conservatively with external Halo immobilization. Type 3 fractures are inherently unstable and are managed operatively. While an anterior approach, posterior approach, and combined anterior-posterior approach are described, several papers report little standardization between spinal centres. Individual surgeon preference is noted to largely dictate the surgical approach utilized and fortunately no significant difference, between the surgical approach used and the fusion rate, is confirmed across several papers. We report a case series of four patients who presented to our unit with Levine and Edwards Type 2, 2A and 3 fractures who we managed operatively. Our case series adds to the vast literature on the subject however is unique in that is provides insight into the South African experience.