Multipoint Annulus Fibrosus Infiltration in PTED for Giant Central Lumbar Disc Herniation: A Case Report

Background In the treatment of lumbar disc herniation (LDH), full-endoscopic techniques have been widely recognized for their minimal invasiveness and rapid recovery. However, central giant disc herniation accompanied by severe spinal stenosis remains a challenge for percutaneous transforaminal endoscopic discectomy (PTED). During conventional procedures under local anesthesia, patients often experience excruciating pain and reflex limb movements when instruments touch or manipulate the highly innervated outer annulus fibrosus and posterior longitudinal ligament. This significantly increases the risk of nerve injury and surgical difficulty. This article introduces a modified technique of PTED with multipoint infiltration anesthesia of the annulus fibrosus in the lateral recess to effectively resolve these challenges. Case Presentation: A 29-year-old male was admitted with a 5-month history of bilateral radicular pain in the lower extremities. Imaging revealed a central giant LDH at the L4-5 segment with severe dural sac compression and corresponding spinal stenosis. The patient underwent PTED under local infiltration anesthesia. Intraoperatively, after adequately exposing the lateral recess, the patient's visual analogue scale (VAS) score for back pain reached 9 when the herniated annulus fibrosus was touched. Subsequently, the surgeon used an annulus suture cannula to perform multipoint visualized infiltration anesthesia in the annulus fibrosus adjacent to the nerve root, injecting 5 ml of 0.5% lidocaine. After the anesthesia took effect, the maximum VAS score upon touching the annulus dropped to 3. This excellent analgesic effect enabled the surgeon to successfully remove the incarcerated nucleus pulposus and advance the endoscope across the midline to the contralateral lateral recess for exploration and decompression. The patient's bilateral radicular pain was significantly relieved on the day of surgery. MRI and CT scans performed 3 days postoperatively confirmed that the central spinal canal was adequately decompressed without obvious compression, and bilateral lateral recesses were fully decompressed. Conclusion Multipoint infiltration anesthesia of the annulus fibrosus in the lateral recess is a simple, safe, and highly effective adjunctive technique. It overcomes the pain bottleneck of conventional local anesthesia, providing high-quality anesthesia and decompression outcomes for central giant LDH.