Clinical Application of Percutaneous Transforaminal Endoscopic Surgery in Lumbar Discal Cyst.

BACKGROUND: Discal cyst is a very rare disease, which can cause intractable low back pain and radiating leg pain. Its symptoms are hard to distinguish from lumbar disc herniation. The best treatment of discal cysts is still controversial. Most lumbar disc cysts were treated surgically, while most studies of percutaneous transforaminal endoscopic surgery were case reports. The purpose of this study was to investigate the clinical value of the percutaneous transforaminal endoscopic surgery for the lumbar discal cyst. METHODS: A retrospective study was conducted in 9 patients with a discal cyst from June 2016 to November 2018. All of them had been treated by percutaneous transforaminal endoscopic surgery via a superior vertebral pedicle notch approach. Surgical outcomes were evaluated in preoperative and postoperative periods using a Visual Analogue Scale (VAS) for leg pain and the Oswestry Disability Index (ODI). At the final follow-up, patients were evaluated for clinical efficacy using modified Macnab criteria. RESULTS: All 9 patients had remission of symptoms after removal of the discal cysts. Postoperative magnetic resonance imaging showed that all patients had complete excision of discal cysts and complete decompression of the treated segmental. There were no recurrent lesions during the follow-up period. The mean operation time was 68.67+/-14.02min. The mean hospitalization time was 4.22+/-1.64 days. Preoperative VAS and ODI score improved significantly after surgery. VAS leg score improved from 7.88+/-1.05 preoperatively to 1.78+/-0.66 at the final follow-up (P<0.05), and ODI score improved from 53.65+/-12.46 to 16.25+/-8.76 (P<0.05). According to the modified MacNab criteria, 5 patients (55.6%) were rated excellent, 3 patients (33.3%) were rated good, and 1 case (11.1%) was rated fair at the final follow-up, with an overall excellent and good rate of 88.9%. There were no serious complications during the follow-up. CONCLUSION: Percutaneous transforaminal endoscopic surgery could be a safe, minimally invasive surgical treatment for the discal cyst, particularly suitable for patients who cannot undergo general anesthesia.