C2 over C3 spondyloptosis in a case with absent posterior elements. Report of an unusual case and analysis of treatment options.

We report an extremely rare anomaly in a 31-year-old male patient, where the posterior elements of the axis were almost completely absent and the anterior elements were dislocated anterior to the body of the C3 vertebra. The body of C3 caused severe compression of the high cervical cord. A radical transoral decompression and plate and screw fixation resulted in sustained clinical improvement. The relevant literature is briefly reviewed and the treatment options in such a case are analyzed.