Technical Notes and Clinical Outcomes of Full-Endoscopic Interbody Fusion Via Transforaminal Approach for Hard Disc Herniations in Thoracolumbar Junction.

Objective: Obtaining sufficient decompression and solid fusion and avoiding approach-related injuries simultaneously are still challenging for the treatment of hard disc herniation in thoracolumbar junction. A combined full-endoscopic decompression and interbody fusion via a transforaminal approach was used to achieve this goal. The purpose of this study was to introduce the technical notes and clinical outcomes of this novel technique.

Methods: Twenty segments of hard disc herniations in the thoracolumbar junction of 14 patients treated with full-endoscopic interbody fusion via the transforaminal approach between January 2018 and September 2021 were analyzed. The patients were an average age of 43.3 years. Full-endoscopic interbody fusion and discectomy via the transforaminal approach were performed under local anesthesia, followed by percutaneous pedicle screw system fixation under general anesthesia. Imaging, including magnetic resonance imaging (MRI), computed tomography (CT), and X-ray, was carried out. MRI was performed on the second day and 3 months postoperatively. CT was performed on the second day, 6 months, and 1 year (as needed) postoperatively. Back and radicular pain, neurological function, and thoracic spine function were scored using a visual analog scale, the Nurick scale, and modified Japanese Orthopaedic Association (mJOA) scale, and the Oswestry disability index at 1 week, 3 months, 6 months, and 1 year postoperatively.

Results: All the operations were successfully completed, and no intraoperative conversion of the surgical methods occurred. Postoperative thoracolumbar junction MRI and CT examinations of all the patients revealed a sufficiently decompressed spinal cord or cauda equina, without any residual compression. At the 1-year follow-up, all the surgical segments were fused. Back and radicular pain was relieved in all the patients, and neurological function was restored. The average recovery rate of the mJOA was 72.5%, including seven excellent, five good, and two fair cases. Although dural tears occurred in two cases during the operation, no cerebrospinal fluid leakage or pseudomeningocele occurred during follow-up. No other surgical complications were noted.

Conclusions: A combined full-endoscopic decompression and interbody fusion via a transforaminal approach can achieve complete spinal canal decompression and solid interbody fusion with fewer approach-related injuries. It is a safe and effective minimally invasive spine surgery for treating hard disc herniation in the thoracolumbar junction.