Unusual appearance of an en plaque meningioma of the cervical spinal canal. A case report and literature review

A case report of a patient with cervical spinal cord and nerve root compression caused by a meningioma en plaque together with calcification of the posterior longitudinal ligament is presented,with a review of the literature. To present the diagnosis of a calcified dural meningioma en plaque, with extradural extension into the ligamentum flavum, in a woman with cervical myelopathy and neuropathy. This case demonstrates that the cervical spine can be involved in dural meningioma en plaque with calcifications, in a manner mimicking ossification of the ligamentum flavum, which has never been previously reported. A patient presenting with cervical cord and nerve root compression caused by ossification of the posterior longitudinal ligament and a concurrent calcified dural meningioma en plaque was treated surgically and has made a gradual recovery. Imaging studies,surgical findings, and histopathologic evaluation were analyzed to support the diagnosis. At surgery, ossification of the posterior longitudinal ligament was noted, along with a calcified lesion involving the posterior cervical dura and the adjacent ligamentum flavum. A calcified meningioma was diagnosed by histopathologic examination of the dural-based lesion. Although previously not described, the diagnosis of calcified dural meningioma en plaque should be considered in all patients presenting with spinal cord and/or nerve root compression,even at cervical levels. Although ossification of the posterior longitudinal ligament and ossification of the ligamentum flavum are more common etiologies of partially circumferential spinal calcification, dural-based meningiomas with extension into the surrounding ligaments demand early recognition because they can be associated with a poorer prognosis.