Implementation of Intraoperative Cone-Beam CT (Loop-X) in an Established Robotic-Assisted Pedicle Screw Program: An...

Background/Objectives: Reliable intraoperative imaging is essential for robotic-assisted (RA) pedicle screw placement. Mobile intraoperative cone-beam CT (iCBCT) systems like Loop-X have been introduced into RA workflows, but implementation data remain limited. We evaluated whether Loop-X introduction was associated with efficiency or safety, and whether associations differed by surgeon experience. Methods: We performed a retrospective epoch-based cohort study of 146 patients undergoing RA pedicle screw placement using 3D C-arm navigation (3D-BV) or Loop-X iCBCT. Outcomes were operating room (OR) time, estimated blood loss (EBL), and length of stay (LOS). The safety endpoint was 30-day complications (Clavien-Dindo grade III or higher). Multivariable regression models adjusted for patient- and procedure-related covariates; the complication model was kept parsimonious because of the limited number of events. Interaction terms tested surgeon experience. Results: After adjustment, implementation phase was not independently associated with OR time (β 30.76 min, 95% CI -31.97 to 93.48; p = 0.33), EBL (β -19.94 mL, 95% CI -287.01 to 247.14; p = 0.88), or LOS (β 3.21 days, 95% CI -3.31 to 9.72; p = 0.33). No significant interaction with surgeon experience was detected. Major complications occurred in 16 of 146 cases (11.0%) and were not associated with Loop-X implementation (OR 0.41, 95% CI 0.10-1.74; p = 0.224). Patient factors and procedural complexity were the main determinants of outcomes. Conclusions: In this cohort, Loop-X implementation in an RA pedicle screw program was not associated with deterioration in perioperative efficiency or short-term safety after adjustment. These findings support feasibility in practice, but do not establish superiority, equivalence, or imaging-specific effects.