Unilateral Biportal Endoscopic Excision of a Lumbar Discal Cyst: A Case Report and Technical Note

Lumbar discal cysts are rare intraspinal extradural lesions that can mimic lumbar disk herniation and present with radiculopathy. Although transforaminal and interlaminar endoscopic techniques have been described for their excision, reports describing management using unilateral biportal endoscopy (UBE) are limited.

A 27-year-old male presented with chronic low back pain and progressive left-sided radiculopathy refractory to conservative treatment, including an epidural steroid injection. Imaging studies revealed a left paracentral discal cyst at the L3-L4 level causing compression of the exiting L3 and traversing L4 nerve roots. The patient underwent cyst excision using a UBE approach. The patient experienced significant post-operative pain relief (Visual Analogue Scale - leg pain improved from 8/10 preoperatively to 1/10 postoperatively) and was discharged the following day. At 6-month follow-up, he remained asymptomatic with no recurrence seen in the magnetic resonance imaging scan.

This case demonstrates that UBE is a safe and effective minimally invasive option for excision of lumbar discal cysts. The technique offers excellent visualization, neural decompression, and early recovery, and may represent a valuable alternative to conventional open, microscopic, or full endoscopic approaches.