Intradural disc herniations pathogenesis, clinical picture, diagnosis and treatment.

The relatively rare occurrence and uncertainty about pathogenesis of intradurally displaced disc herniations stimulated an anatomico-pathological study into intradural disc herniations. The relation between the ventral dura and posterior longitudinal ligament in the cervical, thoracic, lumbar and sacral regions were examined macroscopically and microscopically, and ventral and dorsal dural thickness was compared in 20 adult autopsies on patients who died from various causes; in addition, 20 late abortions and newborn cadavers were investigated in the same way. In this study, a total of 40 autopsies has shown that the ventral dura is most frequently and firmly attached to the posterior longitudinal ligament at the L4-L5 level and these adhesions may be congenital. In the adult cadavers dorsal dura was found to be thicker than the ventral dura in the lumbar and lower cervical interspaces. Three personal clinical cases of intradurally herniated disc prolapse are shortly described and the diagnosis and management of this pathology discussed.