Efficacy and safety for combination of trephine with a new tool in foraminoplasty in percutaneous endoscopic transforaminal discectomy: a retrospective study

Abstract

Background: Foraminoplasty is a critical step in percutaneous endoscopic transforaminal discectomy (PETD) for the treatment of lumbar disc herniation (LDH). It is usually performed using trephine under fluoroscopy guidance and is especially suitable for beginners. However, foraminoplasty with trephine may sometimes leave the cut bone in the body and then even cause neural symptoms. We designed a new tool named anchor drill to assist trephine in performing foraminoplasty. The purpose of this study was to evaluate efficacy and safety for combination of trephine with anchor drill in foraminoplasty.Methods: A retrospective review was performed to identify patients with lumbar disc extrusion or sequestration between January 2018 to January 2021 who underwent PETD. Foraminoplasty using trephine alone or trephine combined with anchor drill under fluoroscopy guidance was performed in all surgeries. Duration of foraminoplasty, endoscopic operation time, fluoroscopy time, bone residual incidence after foraminoplasty and perioperative complications were reviewed. Visual analog scale (VAS) and Japanese Orthopedic Association (JOA) scores were assessed before, 1 day, 3 months and 12 months after surgery for all patients.Results: A total of 100 patients were included (55 in combination group, 45 in trephine group). Bone residual incidence after foraminoplasty of combination group was 9.09%, which was significantly lower than that of trephine group with 33.33% (P＜0.05). Mean endoscopic operation time of combination group was significantly shorter than that of trephine group (P＜0.05). Fluoroscopy time and duration of foraminoplasty showed no significant differences between two cohorts. Total perioperative complication incidence was lower in combination group, among which the neural irritation incidence showed significant difference (combination group: 3.64%, trephine group: 17.78%, P＜0.05). No severe vascular and neurological complications occurred in perioperative period. VAS and JOA scores were compared before and after surgery and differences were statistically significant for all patients (P＜0.001). At each follow-up visit, no significant differences were found in VAS and JOA scores between two cohorts. Conclusions: Combination of trephine with anchor drill was demonstrated to be safe and effective in foraminoplasty in PETD, improving success rate of foraminoplasty and reducing neurological complications relative to using trephine alone.