Syringomyelia (sear-IN-go-my-EEL-ya) is a disorder in which a fluid-filled cyst forms within the spinal cord.
This cyst, called a syrinx, expands and elongates over time, damaging the spinal cord. Since the spinal cord connects the brain to nerves in the extremities, this damage may cause pain, weakness, and stiffness in the back, shoulders, arms, or legs.
Symptoms vary among individuals. Other symptoms may include headaches and a loss of the ability to feel extremes of hot or cold, especially in the hands. Signs of the disorder tend to develop slowly, although sudden onset may occur with coughing or straining. If not treated surgically, syringomyelia often leads to progressive weakness in the arms and legs, loss of hand sensation, and chronic, severe pain.
In most cases, the disorder is related to a congenital abnormality of the brain called a Chiari malformation, which causes brain tissue to protrude from its normal location in the back of the head and into the cervical or neck portion of the spinal canal. Syringomyelia may also occur as a complication of trauma, inflammation, spinal cord injury, hemorrhage, spinal cord tumors, or other conditions. Symptoms may appear months or even years after the initial injury, starting with pain, weakness, and sensory impairment originating at the site of trauma. Some cases of syringomyelia are familial, although this is rare.
Symptoms usually begin in young adulthood, with symptoms of one form usually beginning between the ages of 25 and 40. If not treated surgically (when needed), syringomyelia often leads to progressive weakness in the arms and legs, loss of hand sensation, and chronic, severe pain. Symptoms may worsen with straining or any activity that causes cerebrospinal fluid pressure to fluctuate.
Some individuals may have long periods of stability. Surgery results in stabilization or modest improvement in symptoms for most individuals. Delay in treatment may result in irreversible spinal cord injury.
If there are no symptoms, syringomyelia is usually not treated and the person is monitored by a neurologist or neurosurgeon. Surgery is usually recommended for individuals with symptomatic or progressive syringomyelia, with the type of surgery and its location dependent on the type of syrinx.
In persons with syringomyelia that is associated with the Chiari malformation, a procedure that removes skull bone and expands the space around the malformation usually prevents new symptoms from developing and results in the syrinx becoming smaller.
In some individuals it may be necessary to drain the syrinx, which can be accomplished using a catheter, drainage tubes, and valves. Syringomyelia can recur after surgery, making additional operations necessary. Whether treated or not, many individuals with syringomyelia are told to avoid activities that involve straining.