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Dorsally Sequestered Cervical Disc Herniation

Study Design. A case report of dorsally sequestered cervical disc herniation. Objective. To present an unusual case of dorsally sequestered cervical disc herniation and to briefly review the literature on this condition. Summary of Background Data. There have been few reports of migration of cervical disc herniation to the posterior surface of the spinal canal. Methods. A 72-year-old man experienced a sudden episode of weakness of both lower extremities after playing golf, which gradually progressed, resulting in inability to walk without aid. Magnetic resonance imaging revealed a well-defined, oval mass lesion on the left dorsal aspect of the spinal canal, which compressed the dural sac at the level of C7. The mass lesion was isointense on T1-weighted images and heterogeneously hyperintense on T2-weighted images, and contrast-enhanced magnetic resonance imaging demonstrated peripheral enhancement of the mass lesion. Results. The patient underwent surgery consisting of decompressive laminoplasty of C6 to C7, partial laminectomy of T1, and removal of the mass lesion. Histologically, the mass lesion was diagnosed as a dorsally sequestered disc herniation. After surgery, the weakness of both lower extremities gradually resolved, and the patient was able to walk without assistance at 2 weeks after surgery. Conclusion. It is important to appropriately differentiate dorsally sequestered disc herniation from other epidural mass lesions such as extradural tumor before operation and essential to perform early and sufficient surgical decompression of the spinal cord to prevent poor postoperative course in cases of acute onset and rapid progression of the paralysis caused by disc herniation.