Cervical Intradural Disc Herniation

Study Design. A case report of anterior en bloc resected cervical intradural disc herniation and a revieew of the litterature. Objective. To discuss the pathogenesis of cervical intradural herniation. Summary of Background Data. Including this study case, only 17 case of cervical intradural disc herniation have been reported. There have been few detailled reports concerning the pathogenesis of cervical intradural disc herniation. Methods. A cervical intradural disc herniation at C6-C7, with localized hypertrophy and segmentally ossified posterior longitudinal ligament, is reported in a 45 year old man who had Brow-Sequars syndrome diagnoside on neurologic examination. Neurologic, operative, and histologic findings, particularly posterior vertebral portion of C6 and C7, were evaluated for discussion of the pathogenesis. Results. Adhesion of dura mater and hypertrophic posterior longitudinal ligament was observed around a perforated portion of the herniated disc, and histologic study showed irregularity in fiber alignement accompagnied by scattered inflammatory cell infiltration and hypertrophy in the posterior longitudinal ligament. The cervical intradural disc herniation was removed successfully and follwed by C5-Th1 anteriorinterbody fusion with fibular strut graft. Neurologic recovery was complete execpt for minor residual sensory disturbance in the leg 7 years after the surgery. Conclusions. Cervical intradural disc herniation is an extremely rare condition. The pathogenesis remains obscure. Only 16 cases have been reported in the litterature, and there had been little discusion concerning the local pathology of the herniated portion. The pathogenesis of the disease in the patient reported here was considered to be the adhesion and fragility of dura mater and posterior longitudinal ligament. This was caused by hypertrophy, with chronic inflamation and ossification of the posterior longitudinal ligament sustaining chronic mechanical irritation to the dura mater and posterior longitudinal ligament. This was caused by hypertrophy, with chronic inflammation and ossification of the posterior longitudinal ligament sustaining chronic mechanical irritation to the dura mater, leading to perforation of the herniated disc by an accidental force.