Letter to editor concerning: “Intradural lumbar disc herniation: report of five cases with literature review”

Abstract

We have a point we would like to make in reference to the article entitled ''Intradural lumbar disc herniation: report of five cases with literature review'', published by Ducati et al. [1] in European Spine Journal. Our attention was drawn to the fact that this author made no reference to a number of studies previously published by us [2,3] and other authors [4,5] which mention the association of intradural herniations or cysts with gas within the spinal canal.Moreover, we had already advised in our previous study of the possible need for intradural exploration where the CT or MRI imaging studies show the existence of gas within the canal and the intraoperative findings do not explain the patient's symptoms.

Intradural disc a diagnostic dilemma: Case series and review of literature

“…Other case series have also reported high incidence cauda equina syndrome in cases of intradural disc. [ 2 ] Three out of four cases of cauda equina in our series were associated with sudden deterioration in the power of lower limb muscle groups. We suspect that intradural herniation of disc was synchronous with cauda equina syndrome in these cases, which was very well documented in Case 1.…”

“…The majority of the intradural disc have been reported in the lumbar spine (92%) and most common level reported is L4–L5 disc space. [ 1 2 ] Intradural disc clinically present with high incidence of neurological deficit and cauda equina syndrome compared to extradural disc herniation. [ 3 ] Pathology of intradural disc is still elusive but studies suggest that probably due to firm anatomic adhesions between the anterior wall of the dural sac and the posterior longitudinal ligament (PLL), at the L4–L5 level in cases of dural perforation, the herniated disc perforates the annulus fibrosis, PLL, and the dura mater simultaneously at this level.…”