Clinical and radiological evaluation of cortical bone trajectory screw placement using patient-specific 3D templates: a multicentric prospective study

PURPOSE: This study assessed the clinical safety and radiological efficacy of lumbosacral cortical pedicle screw placement using 3D printed patient specific templates in the lumbar spine. METHODS: 101 patients affected with degenerative disc(s) were enrolled in a multicentric study. We prospectively reviewed them in terms of radiation exposure, fusion rate, pedicle screw placement accuracy, clinical outcomes, and complication rates within 1 year after surgery. All screws were placed following the Cortical Bone Trajectory (CBT) using a 3D patient-specific guide (MySpine MC, Medacta). RESULTS: At 1 year after surgery, 83.8% of patients demonstrated successful bone fusion. Significant improvements were observed in terms of disability, quality of life, and pain scores starting from day 1 after surgery. These improvements were sustainable after one year FU (p < 0.001). 416/428 (97,2%) of the screws were correctly placed without a cortical breach; 8 screws were classified as Grade I breach and 4 screws as Grade II. None of the breaches were clinically relevant. No loosening was reported. Complications during surgeries emerged in 3% of cases, but none were directly related to the use of CBT or to the use of the templates. One case of screw breakage was registered at the 7-month follow-up (0.2%). CONCLUSIONS: These observations confirm the safety and effectiveness of patient-specific templates for CBT screw placement. The pre-operatively planned approach offers significant benefits in terms of reduced surgical invasiveness and patient outcomes.