Intradural disk herniation at L1-L2: report of two cases.

CONTEXT: Lumbar intradural disk herniation (IDH) is a rare but serious complication of spinal disk protrusions. Although the pathogenesis of lumbar IDH is still vague, it is believed to be associated with the adhesion of the posterior longitudinal ligament with the ventral wall of the dura. Diagnosis is still difficult despite current neuroradiologic imaging techniques.
FINDINGS: Two women, ages 63 and 69 years, presented with recent exacerbation of back pain. In each case, imaging studies revealed a ventral herniated disk at L1-L2. Both patients underwent surgery and in both cases a hard mass was palpated through the dura. Both patients experienced immediate postoperative relief of back pain following surgery. One patient required fusion and postoperative rehabilitation; her neurologic deficit returned to baseline. CONCLUSION/CLINICAL RELEVANCE: Prompt surgical intervention is indicated for IDH; disk removal allows for symptomatic relief and minimization of neurologic deficit.