Temporary fusionless posterior occipitocervical fixation for a proximal junctional type II odontoid fracture after previous C2-pelvis fusion: case report, description of a new surgical technique, and review of the literature.

PURPOSE: Axial fractures in patients with a previous C2-pelvis posterior instrumented fusion are rare and may be challenging to manage. Motion preservation in the axial spine for these patients is important, as the C1-2 and Occipit-C1 joints are their only remaining mobile spinal segments. In this unique report, we present for the first time the use of a fusionless occipitocervical operation for the treatment of a type II odontoid fracture and unilateral C2 pars fracture adjacent to a previous C2-pelvis posterior instrumented fusion.
METHODS: Case report.
RESULTS: Three years after proximal extension of a T3-pelvis posterior instrumented fusion to C2, the patient sustained a displaced odontoid fracture and unilateral C2 pars fracture after a mechanical fall. She underwent fracture stabilization with extension of instrumentation to the occiput. No attempt at fusion was performed. Post-operatively, she was distraught by severely limited neck range of motion, which was reflected in worsening of health-related quality of life (HRQoL) scores. The fracture healed uneventfully after which the instrumentation from the occiput and C1 were removed, which resulted in improvement of neck range of motion. Two years post-operatively, HRQoL scores showed minimal neck disability (NDI 12), no neck or arm pain (VAS 0), and outstanding general health (EQ-5D 85 out of 100, SF-36 PCS 35.3, SF-36 MCS 41.1).
CONCLUSION: In this one patient, instrumentation without fusion allowed for successful and timely union of a displaced odontoid fracture in a patient with a previous C2-pelvis fusion. Axial range of motion was preserved after instrumentation removal.