Motion-preserving direct osteosynthesis for a C2 complex fracture involving the vertebral body and posterior elements: a case report.

Background: Surgical treatment of C2 fractures often involves fixation across C1-2, which restricts atlantoaxial motion. Because the C1-2 segment plays a major role in cervical mobility, motion-preserving strategies may be desirable in selected cases. We report a case of a complex C2 fracture treated with navigation-assisted motion-preserving fixation. Case Description: A 54-year-old man sustained multiple injuries in a motor vehicle collision, including a C2 fracture involving the vertebral body and posterior elements. He presented with neck pain but no neurological deficits. Computed tomography (CT) demonstrated a fracture line extending from the left vertebral body to the right lamina with minimal displacement. CT angiography showed no vertebral artery injury. The patient remained hemodynamically stable. Considering his occupational demands and preference for early return to activity, surgical treatment was performed on hospital day 5. Under intraoperative navigation, direct osteosynthesis was achieved. A lag screw was inserted to reduce and compress the displaced laminar component. Bilateral pars screws connected by a rod were placed to augment stability without crossing adjacent motion segments or performing fusion. The postoperative course was uneventful. The patient was mobilized early with a hard cervical collar and discharged on postoperative day 12. At 13 months, CT confirmed solid bony union. The patient remained symptom-free with preserved cervical range of motion. Conclusions: Motion-preserving fixation using navigation-assisted direct osteosynthesis achieved stable union in a complex C2 fracture involving both anterior and posterior elements. In carefully selected patients, this strategy may serve as a viable alternative to C1-2 fusion.