Preliminary Report of Full-Endoscopic Spinal Dural Repair Using Double-Arm Sutures With a Biportal Endoscopic System: Technical Note and Feasibility Evaluation in an Ex Vivo Porcine Model

BACKGROUND AND OBJECTIVES: Full-endoscopic spine surgery (FESS) offers a minimally invasive approach with significant advantages, but dural tears, occurring in 2.7% of cases, remain a significant challenge. Nerve rootlet herniation through these defects often requires conversion to open surgery, compromising the benefits of FESS. A newly commercialized dural repair device, DuraStat, facilitates suture needle passage through the dura, presenting an opportunity to evolve the well-established inside-out suture repair techniques from minimally invasive tubular surgery to full-endoscopic procedures. The aim of this study was to validate a biportal full-endoscopic dural repair technique using the DuraStat double-arm suture in an ex Vivo animal model. METHODS: FESS was conducted on fresh porcine cadaveric spines at the L6/S1 segment. A dural defect was meticulously created using endoscopic instruments to simulate intraoperative durotomy with accompanying nerve rootlet herniation. The DuraStat double-arm suture was used in an inside-out technique to achieve approximation of the dural defect. Closure was completed utilizing an extracorporeal knotting technique, with the knot advanced and secured via a knot pusher. Repair times for 2 surgeons were recorded over 5 trials to evaluate the learning curve, assessing the feasibility and efficiency of this repair technique. RESULTS: All repair procedures were completed successfully without complications. The mean repair time decreased significantly, with an approximate 76.5% reduction from trial 1 (mean: 40.5 minutes) to trial 5 (mean: 9.5 minutes). By the fifth trial, repair time was consistently reduced to less than 10 minutes, demonstrating substantial improvements in efficiency and proficiency with repeated practice. CONCLUSION: A full-endoscopic suture repair was performed using the inside-out method with the DuraStat double-arm suture under a biportal endoscopic system on the ex Vivo iatrogenic durotomy porcine animal model. The technique was successfully executed with the repair time reduced to less than 10 minutes after a learning curve of 5 trials.