Irradiation safety, anesthesia time, surgical complications, and patient-reported outcomes in the robotic Mazor X versus fluoroscopy guided minimally invasive transforaminal lumbar interbody fusion surgery: a comparative cohort study.

Objective: Robot-assisted (RA) technology is becoming more widely integrated and accepted in spine surgery. The authors sought to evaluate operative and patient-reported outcomes (PROs) in RA versus fluoroscopy-assisted (FA) pedicle screw placement during minimally invasive surgery (MIS) transforaminal lumbar interbody fusion (TLIF).

Methods: The authors retrospectively studied elective patients who underwent single- or multilevel MIS TLIF for degenerative indication using FA versus RA pedicle screw placement. Patients were selected from September 2021 to May 2023 at a single institution with multiple surgeons whose practice consists of primarily MIS. Outcomes included fluoroscopy dosage per screw, operative time per screw, anesthesia time per screw, estimated blood loss (EBL), screw revision rate, inpatient surgical complications, and minimal clinically important difference (MCID) of Oswestry Disability Index (ODI) and numeric rating scale (NRS) scores at the 6- and 12-month follow-ups. Comparability of groups was analyzed by univariate analysis. Multivariable analysis modeling fluoroscopy time per screw was performed, adjusting for confounders.

Results: One hundred eighty-three patients (n = 133 in the FA group vs 50 in the RA group) were included. Patients in the RA cohort were significantly younger than those in the FA group (mean age 63.8 ± 11.9 vs 59.8 ± 11.0 years, p = 0.037). A total of 932 pedicle screws were placed (mean 5.1, range 4-8 per patient). The RA cohort demonstrated significantly lower intraoperative fluoroscopy dosage per screw (4.9 ± 7.6 mGy per screw vs 20.3 ± 14.0 mGy per screw, p < 0.001), significantly longer anesthesia time per screw (49.1 ± 12.6 vs 43.6 ± 9.2, p = 0.009), and similar operative time per screw (33.3 vs 30.7 minutes, p = 0.125). The screw revision rate for symptomatic radiculopathy was zero in both groups. Revision surgery requiring screw removal or reposition was performed in 4 total cases (RA group: 1/50 for infection; FA group: 2/133 for infection, 1/133 for foraminotomy). Both groups demonstrated significant improvement in PROs at 6 and 12 months compared with preoperatively. Moreover, both groups achieved MCID at similar rates.

Conclusions: When implementing RA technology, one can expect similar perioperative outcomes as FA techniques in addition to significantly lower radiation exposure. Moreover, there is no statistically significant difference in postoperative PROs between RA and FA. Longer anesthesia times may also be encountered, as in this study, which is likely a result of more complex robotic setup and workflow.