P47. TNT: Using technique ‘n’ technology to improve safety and outcomes in AIS

Abstract

<h3>BACKGROUND CONTEXT</h3> Pedicle screw insertion in scoliosis is challenging due to the 3-dimensional deformity and abnormal pedicle morphology. Free hand or fluoroscopic guidance is frequently utilized. Technological advancements have led to more adaptation of computer assisted screw insertion. These involve changing the technique from a ‘tactile feedback' to ‘screen-based guidance'. While improvement in screw accuracy has been documented, an increase in surgical time with increased possibility of blood loss, and risk of infection can occur. Additionally, increased radiation exposure, especially with a subsequent second spin for confirmation after navigation is also a concern in pediatric population. <h3>PURPOSE</h3> This study aims to evaluate the surgical outcomes of a free hand screw insertion followed by intraop CT confirmation and compare to free hand with fluoroscopy and traditional computer assisted approaches. <h3>STUDY DESIGN/SETTING</h3> Retrospective review. <h3>PATIENT SAMPLE</h3> Retrospective chart review of 289 AIS patients between 2015 and 2020 from a single institution and 356 AIS from NSQIP 2012-2018 database undergoing posterior spinal fusion. <h3>OUTCOME MEASURES</h3> Radiographic outcomes and surgical outcomes including radiation dose, blood loss, operative time and 30-day complication rates. <h3>METHODS</h3> Part I: 152 patients were operated using the freehand technique ‘n' AIRO technology approach (TNT group); 137 were operated using freehand anatomic and fluoroscopy (Fluoro Group). Radiographic measurements, and clinical outcomes including radiation dose, blood loss, operative time and 30-day complications were compared. Part II: 152 TNT patients were compared to 356 AIS patients from the NSQIP database that were operated on using computer-assisted navigation between 2012 and 2018 (Navigation Group). Operative time, blood loss and 30-day complications were compared. All data was presented as mean and frequencies where appropriate. Fisher's Exact and Kruskal-Wallis tests were used for statistical analysis. <h3>RESULTS</h3> Part I: Average radiation dose for TNT patients was 8.3 mGy compared to 3.5 mGy for the fluoro group (p < 0.001). Average radiation time was 12.6 seconds for the TNT group versus 29.8 seconds for Fluoro (p < 0.001). Operative time was significantly shorter for the TNT patients with an average of 236.6 minutes versus 308.8 minutes (p < 0.001). TNT patients had significantly less blood loss than fluoro patients (444 cc vs 625 cc, p < 0.001). 17 (11.1%) of TNT patients required transfusion compared to 24 (17.5%) Fluoro patients (p < 0.001). Two (2.3%) patients in the TNT group returned within 30-days for superior mesenteric artery syndrome. 5 (3.6%) Fluoro patients returned within 30 days, four for surgical site infections requiring irrigation and debridement, and one patient returned for deep vein thrombosis. Part II: TNT Group had a mean operative time of 236.6 minutes compared to 352 for the Navigation group (p < 0.001). 73.6% of Navigation patients were transfused versus 9.2% of TNT patients (p < 0.001). Navigation patients had significantly more 30-day complication than TNT patients (p < 0.001). Most Navigation returns were deep wound infection, sepsis and reoperation. In contrast, TNT patients only had two cases of superior mesenteric artery syndrome. <h3>CONCLUSIONS</h3> As novel technology allows for better anatomic bone visualization, surgeons should implement these innovations into their technique accordingly, while maintaining surgical control. This technique and technology approach allows for adopting technology into surgical approach rather than restructuring the surgical approach. This happy medium helps with screw accuracy without prolonging surgical time, blood loss and associated complications and has superior surgical outcomes compared to both traditional fluoroscopy and computer assisted approaches. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.