ABSTRACT
Split-type C1 lateral mass fractures have a propensity for progressive fracture displacement. Since almost all cases end up showing progressive fragment diastasis, many authors recommend early surgical treatment. However, placing a C1 lag screw through a C1 split fracture is a challenging task. To overcome this, we designed a patient-custom three-dimensional (3D)-printed guide plate. We present the case of a 57-year-old female patient with a C1 lateral mass split fracture. Considering the amount of fragment translation, primary osteosynthesis was proposed. To purchase both fragments, placement of a lag screw was assisted intraoperatively by a custom 3D-printed composite guide plate, which enabled us to accurately place the screw. After an uneventful procedure, the patient was discharged from hospital after 72 h. Computed tomography scan performed at 12 months showed good fracture consolidation. The use of a patient-specific guide to place a lag screw through a split fracture of the atlas proved to be a safe, accurate, and inexpensive alternative to intraoperative imaging integrated with image-guided surgery.