Fig. 1From: Comparison of the total and hidden blood loss in patients undergoing single-level open and unilateral biportal endoscopic transforaminal lumbar interbody fusion: a retrospective case control studyPhotographs of the intraoperative scene. A Arrangement of the incisions. ▲A viewing portal.●A working portal. ■Percutaneous pedicle screw. B Intraoperative view of biportal endoscopic spinal surgeryBack to article page