Destruction of gray and white matter adjacent to the central canal of the cervical spinal cord leads to cavitation and fluid collection within the cord
Associated with Arnold-Chiari malformation
loss of pain and temperature appreciation in a "cape" distribution owing to the destruction of fibers crossing in front of the central canal
Typically, there is a dissociated sensory loss at the level of the lesion; pinprick and temperature appreciation are impaired, but light touch sensation is preserved(Dissociate anesthesia is the hallmark)
And the syrinx is at the level of C6-C7 vertebrae.
Its a developmental abnormality...one of the hypotheses is that there is abnormality in CSF flow(obstruction/pressure) which leads to cavity formation...this is supported by its association with arnold chiari malformation(More than 50% of these cases have Syringomyelia)...cavity formation can also occur after trauma, due to some tumors...
This is commonly seen in cervical region...I dont know why here only...i will try getting more info..