Sacroiliac Joint Fusion: Fusion Rates and Clinical Improvement Using Minimally Invasive Approach and Intraoperative Navigation and Robotic Guidance

STUDY DESIGN: This study adopted a retrospective study design. PURPOSE: This study was designed to describe the fusion rate and technique and patient subjective improvement after sacroiliac (SI) joint fusion using a minimally invasive surgical (MIS) approach. OVERVIEW OF LITERATURE: The SI joint can mimic radicular or discogenic pain localized to the lower back, gluteal region, or sacral region, posing a challenge in the diagnosis and treatment. This study determines the radiological fusion rate and patient reported subjective clinical outcomes of SI joint fusion using an MIS approach, comparing the use of the Rialto SI joint fusion system (Medtronic, Minneapolis, MN, USA) with the help of the Stealth Navigation System with the use of ExcelsiusGPS Robotic Navigation Platform (Globus Medical Inc., Audubon, PA, USA) using SI-LOK screws (Globus Medical Inc.). METHODS: In this retrospective study, 43 consecutive patients who underwent SI joint fusion between August 2017 and February 2020 were enrolled; 60 SI joints were fused. The patients’ fusion was documented on computed tomography or X-rays, and Visual Analog Scale (VAS) scores were used to determine patient subjective clinical outcomes. RESULTS: A total of 60 joints were fused, including 26 joints fused using robotic guidance and 34 joints fused using the Stealth Navigation System. Student t-test was used to compare the mean preoperative VAS score (7.52±1.3) with the mean postoperative VAS score at the 12-month follow-up (1.43±1.22) (p<0.05). The SI joint fusion rate using this technique was 61% at 6 months, 96.4% at 12 months, and 100% at 18 months. CONCLUSIONS: The use of navigation guidance or robotic assistance enables accurate percutaneous screw placement across the SI joint. The use of bone morphogenetic protein in the screw bore hastens fusion across the joint, improving patient-perceived pain.