Percutaneous endoscopic transforaminal discectomy (PETD) for the treatment of ossification occupation of the lumbar spinal canal is technically demanding. The purpose of this study was to describe an endoscopic cave-in decompression technique in PETD for ossification occupation of the lumbar spinal canal and to report the clinical results.

From May 2018 to June 2020, 23 consecutive cases, diagnosed in our institution as ventral ossification in the lumbar spinal canal and treated with PETD, were evaluated. The endoscopic cave-in decompression technique was performed. We analyzed the clinical outcomes on a visual analogue scale (VAS) and the Oswestry Disability Index (ODI). Perioperative data and complications rate were also recorded.

Mean follow-up was 15.7±2.8months. Mean preoperative VAS score for low-back pain was 5.65±1.43, and decreased to 0.57±0.5 at final follow-up. Mean preoperative VAS score for leg pain was 5.48±1.38, and decreased to 0.56±0.5 at final follow-up. Mean preoperative ODI score decreased from 33.04±5.28 preoperatively to 8.7±2.54 at last follow-up. One patient experienced transient postoperative hypoesthesia, and one developed a mild transient decline in muscle strength; both recovered progressively. Postoperative CT and MRI showed that the ossification was effectively removed and the nerve root and dural mater was completely decompressed in all cases.

The endoscopic cave-in decompression technique in PETD is a safe and effective treatment method for selected patients with ossification occupation of the lumbar spinal canal.