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Robotic-guidance allows for accurate S2AI screw placement without complications

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The study design is retrospective, multi-surgeon, single-center review. The objective is to evaluate complication rates, revision rates, and accuracy grading for robotic-guided S2 alar-iliac (S2AI) screws. Sixty-five consecutive patients underwent S2AI fixation (118 screws) as part of a posterior spine fusion using robotic-guidance. Screws were placed percutaneously in 14 cases and 51 were placed in an open fashion by three board-certified spine surgeons using the Mazor core technology robotic systems (Mazor X, n = 42; Mazor XSE, n = 23). Medical charts were retrospectively reviewed for revisions and complications. All patients were followed for 90 days or greater. Postoperative CT scans were obtained in 22 of the 51 patients, allowing for 46 screws to be reviewed by an independent neuroradiologist who graded the screws for accuracy. There were no intraoperative or postoperative complications associated with S2AI screw placement. There were no revisions found to be related to the S2AI screw placement. All 46 screws evaluated with postoperative CT scans were reported as being at the highest level of accuracy, grade A, with a breach distance of 0 mm (no breach). The robotic-guided technique for S2AI screw placement is a reliable method to achieving pelvic fixation with low complication and revision rates. In addition, a high degree of accuracy can be achieved without relying on visible and tactile landmarks needed for the freehand technique or the additional radiation associated with fluoroscopic-guidance.

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Correspondence to Christopher R. Good.

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Conflict of interest

CRG has received consulting fees from K2M/Stryker, Medtronic, and Mazor and is on an advisory board for Stryker, Augmedics, Medtronic, has received royalties from K2M/Stryker, Medtronic and has stock in Augmedics and NSite. EJ has received consulting fees from Stryker and Precision Spine. CMH has received consulting fees from Globus Medical, and Spineart. LDO, AET, TCS, FRB, DB, KMG, and RR have no other conflicts of interest to declare.

Ethical approval

This study was approved by a centralized IRB, Advarra, on May 16th (Pro00042720). This study was conducted in accordance with the 1964 Helsinki Declaration, its amendments, and other equivalent ethical standards. All study participants or their legally authorized representative signed written informed consent, included in the Notice of Privacy Practices, for study enrollment and publication prior to surgery.

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Good, C.R., Orosz, L.D., Thomson, A.E. et al. Robotic-guidance allows for accurate S2AI screw placement without complications. J Robotic Surg 16, 1099–1104 (2022).

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