Key Factors in Fluid Irrigation Control: A Comparative Study of Arthroscope and Monoportal Scope in Biportal Spine Surgery

The purpose of this retrospective study was to compare patient satisfaction and irrigation fluid usage between arthroscopy-based Biportal Endoscopic Decompression (A-BED) and monoportal scope-based biportal decompression, also known as Assisted Full-Endoscopic Spine Surgery (AFESS). A total of 89 patients (52 A-BED, 37 AFESS) who underwent either procedure between September 2020 and April 2024 were included in the study. While arthroscopic scopes have traditionally been used in biportal surgeries, the monoportal scope offers the advantage of self-contained fluid management, allowing for more efficient irrigation. Fluid usage was measured by the number of 2 L saline bottles used per hour of surgery, and postoperative pain was assessed using a Numeric Rating Scale (NRS). Patient satisfaction at two weeks was similar between the groups (p < 0.71), while the AFESS group demonstrated significantly lower irrigation fluid usage (p < 0.001). Additionally, AFESS showed shorter operative times (84.8 min vs 99.3 min, p < 0.01). The monoportal scope's efficient fluid evacuation reduced the need for excess irrigation, contributing to reduced medical resource consumption without compromising patient satisfaction or safety. There was no significant influence of patient characteristics such as age, gender, or BMI on fluid usage, suggesting that the difference is primarily attributed to the surgical technique. No significant differences in complication rates or reoperations were observed between the two groups. AFESS thus shows potential for reducing irrigation-related risks and improving surgical efficiency while maintaining clinical outcomes comparable to the traditional method.