These are tumors that arise from the ependymal cells located at the filum terminale. Filum terminale ependymomas occur throughout life but are most common from ages 20 to 40.
Men are slightly more commonly affected than females.
The clinical features of most extramedullary tumors reflect a slow-growing intraspinal mass. Specific clinical presentations are variable and are largely determined by tumor location. The motor symptoms may be asymmetric initially due to the fact that the tumor is located of to one side. Thoracic tumors present with signs of compression of the spinal cord. Early signs of stiffness and fatigue eventually give way to spasticity.