Routine Application of a Bioabsorbable Cellulose Hemostatic Agent (WoundClot^TM) in Unilateral Biportal Endoscopic...

Objective: Unilateral biportal endoscopic (UBE) lumbar decompression is an effective minimally invasive spine surgery, but postoperative spinal epidural hematoma (PSEH) remains a practical concern. This study evaluated the clinical necessity of routine application of a bioabsorbable cellulose-based hemostatic agent in UBE lumbar decompression. Methods: This retrospective comparative study included 115 patients who underwent UBE unilateral laminectomy and bilateral decompression for lumbar spinal stenosis. Patients were divided into a control group without routine hemostatic agent application (n = 66) and a hemostatic group with routine hemostatic agent application (n = 49). Clinical outcomes, operation time, postoperative drain output, hemoglobin change, and PSEH on postoperative day (POD) 2 MRI were compared. Results: Baseline characteristics were comparable between the groups. Total drain output was significantly lower in the hemostatic group than in the control group (61.50 [50.00-78.50] mL vs. 77.00 [59.85-96.75] mL, p = 0.002), particularly on POD 2 (19.00 [11.20-22.50] mL vs. 25.00 [18.25-40.00] mL, p < 0.001). Operation time was also shorter in the hemostatic group (41.43 ± 6.69 min vs. 45.91 ± 6.32 min, p < 0.001). However, hemoglobin change, clinical outcomes, and PSEH incidence did not significantly differ between the groups. Symptomatic PSEH requiring revision surgery occurred in one control patient and in no hemostatic patients. Conclusions: Routine hemostatic agent application was not associated with a significant reduction in PSEH after UBE lumbar decompression. Although lower POD 2 drain output and shorter operative time were observed in the hemostatic group, the clinical significance of these findings remains uncertain and warrants further prospective study.