The prognosis of patients with syringomyelia is a tricky subject.  The number one goal of treating syringomyelia is to get rid of the syrinx cavity in the spinal cord.  Once this is done, the patient should be "good as new," right? 

Well, it's not that simple.  See, the syrinx cavity can do permanent nerve damage...which is why early treatment is essential.  If a patient has numbness associated with a syrinx, there is a good chance it will go away if the operation is successful.  If the patient has burning pain, this is most likely permanent and can be reduced but not resolved completely.  Finally, if the patient has weakness in their extremities associated with the syrinx, this is also most likely permanent. 

The nature of syringomyelia is progressive, and so treatment to fix the cause of the syrinx is absolutely vital as soon as possible.  Otherwise, the patient will continue to get worse as the damage becomes more and more permanent.