Case series of intradural disc in recurrence of lumbar disc prolapse

Abstract

Intradural disc herniation is a rare entity reported at 0.04–1.1% that occurs most commonly in the lumbar spine particularly at L4–L5 region. There is a paucity of literature due to the rarity of this condition. Intradural disc herniations must be considered in the differential diagnosis of prolapsed intervertebral disc disease especially with recent worsening of symptoms and mismatch of unenhanced magnetic resonance induction (MRI) findings. The confirmation is made with intraoperative findings. An intradural disc herniation is most often diagnosed intraoperatively. Contrast enhanced MRI scan is mandatory for pre-operative diagnosis. We report on two cases presenting to our unit in the form of recurrent intradural disc disease following previous lumbar surgery occurring within 3 months of the index procedure in both cases.

Multispecialty perspective on intradural disc herniation: diagnosis and management - A case report -

“…The first reported case of IDH was in 1942, and since other cases have been reported [ 1 - 4 , 6 , 8 , 9 ], yet it remains a very rare cause of lower extremity radiculopathy and CES [ 1 - 4 , 7 - 9 ]. Most IDH are found in the lumbar spine (95%) with the L4-5 level being the most commonly affected (55%) followed by the L3-4 level (16%) and then the L5-S1 level (10%) [ 2 , 6 ].…”

“…Most IDH are found in the lumbar spine (95%) with the L4-5 level being the most commonly affected (55%) followed by the L3-4 level (16%) and then the L5-S1 level (10%) [ 2 , 6 ]. IDH has a 4:1 male to female ratio with an average age of onset of 50-60 years [ 1 - 4 , 5 - 7 ].…”

“…The pathogenesis for IDH remains uncertain. Several factors are thought to be responsible for this atypical herniation, including narrowing of the spinal canal due to congenital or iatrogenic causes, adhesions between the annulus fibrosus, PLL, and dura, and dura fragility [ 1 - 4 ]. Adhesion formation is thought to be the most important factor [ 2 , 6 - 7 ].…”

“…In normal conditions, the PLL and the dura are loosely attached. However, in the setting of prior spinal surgery, chronic disc herniation and/or traumatic forces dense adhesions may form, predisposing the area to IDH [ 1 - 4 , 6 - 8 ]. These adhesions, attaching the dural sac to the anterior wall of the central canal, may pull extruded disc material into the dural space [ 1 , 7 ].…”

“…Intradural disc herniations (IDH) are very rarely reported in the literature with an estimated incidence ranging between 0.04–1.5%, affecting males more than females with an onset between 50–60 years of age [ 1 , 2 ]. IDH is defined as fragmented disc material that breaks through the annulus, posterior longitudinal ligament (PLL), and dura migrating into the thecal sac.…”