Rare intradural lumbar disc herniation at L1/2: a case report

Intradural disc herniation (IDH) in the lumbar spine is an extremely rare condition, representing only a small percentage of all disc herniations. Despite advanced imaging techniques, IDH is often misdiagnosed as intradural tumor, disc herniation or migrated sequester. Definitive diagnosis is usually established intraoperatively and may be confirmed histologically. This case report describes an L1/2 IDH that was microsurgically removed with the assistance of intraoperative ultrasonography (IOUS) for localization of the lesion. The ventral dural tear, frequently occurring in IDH, was managed using a collagen pad, resulting in an uneventful postoperative course without evidence of cerebrospinal fluid (CSF) leak during follow-up.

We present a 70-year-old female patient with acute back pain, radiating to inner thighs and paraparesis. Magnetic resonance imaging (MRI) showed intervertebral (IV) disc herniation in the L1/2 segment. Subsequent microdiscectomy assisted by IOUS revealed intradurally migrated fragments, which were carefully removed. The ventral dural tear was identified and treated using an absorbable collagen pad. At both 7-week and 18-month follow-up, the patient remained pain-free and showed no new neurological deficits or signs of CSF leakage.

Lumbar IDH remains a rare diagnostic challenge, as preoperative imaging is often inconclusive. This case suggests that intraoperative ultrasound may aid localization of intradural pathology, while collagen-pad repair may provide a useful option for managing ventral dural defects when primary closure is technically challenging, although further research is necessary.