Comparative evaluation of screw accuracy and complications of new C-arm free O-arm navigated minimally invasive cervical pedicle screw fixation (MICEPS) with conventional cervical screw fixation

Study design: Retrospective comparative study. Objective: Comparative study of C-arm free O-arm navigated minimally invasive cervical pedicle screw (MICEPS) fixation with conventional cervical pedicle screw fixation. Methods: Twenty-five patients with different cervical spine pathologies were operated with MICEPS with O-arm navigation (group M; 18 patients) and conventional pedicle screw (group C; 7 patients) from June 2017 to January 2020. Operative time, blood loss were recorded. Preoperative and postoperative radiograms, CT scans and MRI were evaluated. Postoperatively screw position accuracy and angulation was determined on CT. Breach rate was evaluated on CT scan and classified according to Neo grading. Complications if any were noted. Results: The average blood loss in group M and group C was 129 ml and 329 ml, respectively. The average operative time in group M and group C was 77.4 min and 82.3 min, respectively. A total of 148 screws were inserted. In group M, no patient showed grade 2 and 3 breach while in group C, grade 0 and 1 breach was found in 85.7% screws and grade 2 in 14.3% screws. Mean screw medial angulation was 45.2 degrees in group M and 33.4 degrees in group C. There was one dural tear and two C5 palsies in each group. Conclusion: With C -arm free O-arm navigated MICEPS fixation operative time and blood loss are less though not statistically significant. It has less pedicle breach rate, less incidence of neurovascular complications than conventional technique. There is no radiation exposure to operating surgeon and staff.