Percutaneous endoscopic transforaminal discectomy for bilateral symptomatic upper lumbar disc herniation: a retrospective case series with an average 60-month follow-up

To investigate the safety and efficacy of percutaneous endoscopic transforaminal discectomy (PETD) in patients with bilateral symptomatic upper lumbar disc herniation (LDH) using a unilateral transforaminal approach. A total of 22 patients with upper LDH who had bilateral lower-limb symptoms were treated with PETD via a unilateral transforaminal approach from April 2017 to May 2022. The syndrome of cauda equina, Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and Macnab criteria were recorded to evaluate the surgical outcomes. Complications, technical problems, and revision surgery were also noted. All procedures were successfully completed, with a mean follow-up of 60 months(range, 21–83 months). No severe neurovascular injury or technical problem occurred. The scores before the operation, 3 months after the operation, and at the last follow-up were as follows. The mean VAS scores for low back pain were 5.7 ± 1.2 preoperatively, 2.8 ± 1.0 at 3 months postoperatively, and 1.3 ± 1.0 at the final follow-up. While the mean VAS scores for leg pain were 6.5±1.1 preoperatively, 2.2±0.9 at 3 months postoperatively, and 0.7 ± 0.9 at the final follow-up. The mean ODI scores were 36.7±4.5 preoperatively, 19.0±5.3 at 3 months postoperatively, and 4.5 months postoperatively, and 4.5±4.6 at the final follow-up. The postoperative VAS and ODI scores were significantly lower than those before the operation ( P < 0.05). The excellent and good rate of the Macnab criteria was 90.9% (20/22). One patient underwent an open revision surgery because of unsatisfactory outcomes. In this retrospective series, unilateral-transforaminal PETD was associated with sustained clinical improvement in selected patients with bilateral symptomatic upper LDH.This approach may be feasible for surgeons experienced in spinal endoscopy with rigorous surgical techniques. however, larger controlled studies are required to confirm its safety and effectiveness.